Localized chemogenetic silencing of inhibitory neurons: a novel mouse model of focal cortical epileptic activity.

Focal cortical epilepsies are frequently refractory to available anticonvulsant drug therapies. One key factor contributing to this state is the limited availability of animal models that allow to reliably study focal cortical seizures and how they recruit surrounding brain areas in vivo. In this study, we selectively expressed the inhibitory chemogenetic receptor, hM4D, in GABAergic neurons in focal cortical areas using viral gene transfer. GABAergic silencing using Clozapine-N-Oxide (CNO) demonstrated reliable induction of local epileptiform events in the electroencephalogram signal of awake freely moving mice. Anesthetized mice experiments showed consistent induction of focal epileptiform-events in both the barrel cortex (BC) and the medial prefrontal cortex (mPFC), accompanied by high-frequency oscillations, a known characteristic of human seizures. Epileptiform-events showed propagation indication with favored propagation pathways: from the BC on 1 hemisphere to its counterpart and from the BC to the mPFC, but not vice-versa. Lastly, sensory whisker-pad stimulation evoked BC epileptiform events post-CNO, highlighting the potential use of this model in studying sensory-evoked seizures. Combined, our results show that targeted chemogenetic inhibition of GABAergic neurons using hM4D can serve as a novel, versatile, and reliable model of focal cortical epileptic activity suitable for systematically studying cortical ictogenesis in different cortical areas.

Group cognitive behavioral treatment in female soldiers diagnosed with binge/purge eating disorders.

Cognitive behavioral treatment (CBT) is the recommended intervention in bulimia nervosa (BN) and eating disorders not otherwise specified with binge/purge (EDNOS-B/P) symptoms. There are fewer data on its application in a group format. We sought to investigate the effect of group CBT in female soldiers with B/P symptomatology in an open trial design. For this purpose we assessed 64 female soldiers serving in the Israeli Defense Force diagnosed with BN and EDNOS-B/P who participated in a group CBT format of 16 weekly sessions and one follow-up session. In this study, 42 participants (65.6%) completed treatment and 22 participants (34.4%) did not. A total of 39 treatment completers (92.8% of treatment completers) and 19 non-completers (86.4% of treatment non-completers) were assessed around 12 months after treatment. Participants completed at baseline and following treatment questionnaires assessing eating-related symptoms, depression, anxiety, and overall functioning. At follow-up they were assessed for eating-related symptoms. Our findings show only minimal baseline differences between treatment completers and non-completers. Significant improvement from baseline to post-treatment was shown for B/P and restrictive symptoms, depression, anxiety, and overall functioning. At that time, more than a third of treatment completers were abstinent from binging and more than a half from vomiting. The improvement in B/P and restricting symptoms was maintained at 1 year follow-up for treatment completers. At that time around 60% were abstinent from binging and more than 70% from vomiting. Participants not completing treatment were also improved at follow-up but to a lesser extent. The findings of the present study suggest that group CBT may be effective for the treatment of female soldiers with BN and EDNOS-B/P.

Deconstructing the default: cortical subdivision of the default mode/intrinsic system during self-related processing.

Recent brain imaging research has highlighted a new global system of areas termed the Default Mode network (DM), which appears to specialize in intrinsically oriented functions. However, it is still unresolved to what extent this system contains functional subsystems as in the better known sensory and motor cortices. Here, we report that functional subdivisions can be revealed within individual nodes of the DM, such as the Inferior Parietal Lobule (IPL), through the use of different categories of self-oriented tasks. Subjects underwent BOLD fMRI scans during which they were asked to recall self-related positive and negative information in the categories of people and food. These tasks elicited distinct regions of activation within the DM. Importantly, the observed activations were above the activity level in the baseline, no-task condition for these regions. The main subdivision within the DM was observed in the inferior and posterior parietal cortex. Analysis of coherent resting state fluctuations (functional connectivity analysis) revealed that these regions of activation were part of a distinct network of regions within the DM. These results argue against viewing the DM as a unitary system, and are compatible with the notion that, similar to the rest of the cerebral cortex, the DM consists of distinct, functionally specialized subregions.

Mouse spontaneous behavior reflects individual variation rather than estrous state.

Behavior is shaped by both the internal state of an animal and its individual behavioral biases. Rhythmic variation in gonadal hormones during the estrous cycle is a defining feature of the female internal state, one that regulates many aspects of sociosexual behavior. However, it remains unclear whether estrous state influences spontaneous behavior and, if so, how these effects might relate to individual behavioral variation. Here, we address this question by longitudinally characterizing the open-field behavior of female mice across different phases of the estrous cycle, using unsupervised machine learning to decompose spontaneous behavior into its constituent elements.1,2,3,4 We find that each female mouse exhibits a characteristic pattern of exploration that uniquely identifies it as an individual across many experimental sessions; by contrast, estrous state only negligibly impacts behavior, despite its known effects on neural circuits that regulate action selection and movement. Like female mice, male mice exhibit individual-specific patterns of behavior in the open field; however, the exploratory behavior of males is significantly more variable than that expressed by females both within and across individuals. These findings suggest underlying functional stability to the circuits that support exploration in female mice, reveal a surprising degree of specificity in individual behavior, and provide empirical support for the inclusion of both sexes in experiments querying spontaneous behaviors.

Survey of threats and assaults by patients on psychiatry residents.

OBJECTIVE: The authors sought to determine the prevalence of threats and assaults by patients on psychiatry residents, their consequences, and the perceived adequacy of supports and institutional responses. METHOD: Authors conducted an anonymous survey of 519 psychiatry residents in 13 psychiatry programs across the United States. The survey questionnaire inquired about residents' experiences of threats and assaults by patients during their residency training. RESULTS: The response rate for this survey was 39% (N=204). Residents were most commonly threatened (N=175; 86%), physically intimidated (N=145; 71%) or received unwanted advances (N=118; 58%). One-quarter (N=51; 25%) were physically assaulted. Most of the incidents occurred in inpatient settings (N=92; 45%). CONCLUSION: This study, like previous studies on this topic, calls attention to the high number of residents that are affected by violence during their training, and it underscores the need to protect the safety of psychiatry residents and to support those who have been victimized.

Cooperation between the hippocampus and the striatum during episodic encoding.

The hippocampus and the striatum are thought to play distinct roles in learning and memory, each supporting an independent memory system. A fundamental question is whether, and how, these systems interact to jointly contribute to learning and memory. In particular, it remains unknown whether the striatum contributes selectively to implicit, habitual learning, or whether the striatum may also contribute to long-term episodic memory. Here, we show with functional magnetic resonance imaging (fMRI) that the hippocampus and the striatum interact cooperatively to support episodic memory formation. Participants were scanned during a memory encoding paradigm and, subsequently, were tested for memory of encoded items. fMRI data revealed that successful memory was associated with greater activity in both the hippocampus and the striatum (putamen) during encoding. Furthermore, activity in the hippocampus and the striatum was correlated within subjects for items that were later remembered, but not for items that were forgotten. Finally, across subjects, the strength of the correlation between the hippocampus and the striatum predicted memory success. These findings provide novel evidence for contributions of both the striatum and the hippocampus to successful episodic encoding and for a cooperative interaction between them.

AKT inhibitor, GSK690693, induces growth inhibition and apoptosis in acute lymphoblastic leukemia cell lines.

The PI3K/AKT signaling is activated in various hematologic malignancies. We evaluated the effect of a novel, pan-AKT kinase inhibitor, GSK690693, on the proliferation of 112 cell lines representing different hematologic neoplasia. Fifty-five percent of all cell lines tested were sensitive to AKT inhibitor (EC(50)<1 microM), with acute lymphoblastic leukemia (ALL), non-Hodgkin lymphoma, and Burkitt lymphoma showing 89%, 73%, and 67% sensitivity to GSK690693, respectively. The antiproliferative effect was selective for the malignant cells, as GSK690693 did not inhibit the proliferation of normal human CD4(+) peripheral T lymphocytes as well as mouse thymocytes. Phosphorylation of downstream substrates of AKT was reduced in both sensitive and insensitive cell lines on treatment with GSK690693, suggesting that the cause of resistance was not related to the lack of AKT kinase inhibition. Consistent with the role of AKT in cell survival, GSK690693 also induced apoptosis in sensitive ALL cell lines. Overall, our data provide direct evidence for the role of AKT signaling in various hematologic malignancies, especially ALL and some lymphomas.

The social dilemma: prefrontal control of mammalian sociability.

Mammalian social interactions are orchestrated by a wide array of neural circuits. While some aspects of social behaviors are driven by subcortical circuits, and are considered to be highly conserved and hard-wired, others require dynamic and context-dependent modulation that integrates current state, past experience and goal-driven action selection. These cognitive social processes are known to be dependent on the integrity of the prefrontal cortex. However, the circuit mechanisms through which the prefrontal cortex supports complex social functions are still largely unknown, and it is unclear if and how they diverge from prefrontal control of behavior outside of the social domain. Here we review recent studies exploring the role of prefrontal circuits in mammalian social functions, and attempt to synthesize these findings to a holistic view of prefrontal control of sociability.

Tetrasubstituted pyridines as potent and selective AKT inhibitors: Reduced CYP450 and hERG inhibition of aminopyridines.

The synthesis and evaluation of tetrasubstituted aminopyridines, bearing novel azaindazole hinge binders, as potent AKT inhibitors are described. Compound 14c was identified as a potent AKT inhibitor that demonstrated reduced CYP450 inhibition and an improved developability profile compared to those of previously described trisubstituted pyridines. It also displayed dose-dependent inhibition of both phosphorylation of GSK3beta and tumor growth in a BT474 tumor xenograft model in mice.

The Nasopalatine Ducts Are Required for Proper Pheromone Signaling in Mice.

The vomeronasal organ (VNO) specializes in detection of chemosignals, mainly pheromones, which control social communication and reproduction in many mammals. These pheromones must solubilize with nasal fluids before entering the VNO, and it was suggested that they are delivered to and cleared from the VNO by active pumping. Yet, the details of this pheromone delivery process are unclear. In this study, we first constructed a high-resolution 3D morphological image of the whole adult mouse snout, by using ultra-high-resolution micro-CT. We identified a net of micro tunnels starting from the nostrils and extending around and through the VNO. These micro tunnels connect the nasal cavity with the VNO and the oral cavity via the nasopalatine ducts (NPD). Other micro tunnels connect the nasal cavity to the main olfactory epithelium. We next demonstrated that physical obstruction of the NPD severely impairs the clearance of dissolved compounds from the VNO lumen. Moreover, we found that mice with blocked NPD display alterations in chemosignaling-evoked neuronal activation in brain regions associated with the vomeronasal system. Finally, NPD-blocked male mice exhibit reduced preference for female chemosignals, and impaired social interaction behavior. Taken together, our findings indicate that the NPD in mice are connected to both the nasal and oral cavity, serving an essential role in regulating the flow of soluble chemosignals through the VNO, and are required for proper pheromone-mediated social communication.

Author Correction: Dynamics of social representation in the mouse prefrontal cortex.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Salivary Cytokines in Children with Nephrotic Syndrome versus Healthy Children: A Comparative Study.

BACKGROUND: The aims of this study were to compare salivary cytokines and total protein between children with nephrotic syndrome (NS) and healthy children, and to examine whether saliva parameters can differentiate between steroid sensitivity and resistance and between disease remission and relapse. METHODS: Twenty-seven children with nephrotic syndrome were classified according to steroid sensitivity and resistance, and disease remission and relapse. Twenty healthy children served as controls. Whole saliva samples were collected from all the participants. Urine and blood tests done on the same day as the saliva collection were recorded. Salivary total protein was quantified using bicinchoninic acid and IFNγ, IL-4, IL-8, IL-6, and IL1ß levels using ELISA. RESULTS: The mean ages of the nephrotic syndrome and control groups were 11.3 ± 2.4 and 9 ± 4.2, respectively. Compared to the control group, for the nephrotic syndrome group, total salivary protein was significantly lower, as were the levels of all the cytokines examined except IFNγ. Statistically significant differences were not found in any of the salivary markers examined between the children with nephrotic syndrome who were treatment sensitive (n = 19) and resistant (n = 8). Protein and IL-8 salivary levels were lower in the active (n = 7) than in the remission (n = 20) group. CONCLUSIONS: Salivary parameters distinguished children with nephrotic syndrome in relapse from healthy children. This may be due to decreased salivary protein excretion, which reflects decreased plasma levels, consequent to proteinuria. Accordingly, salivary markers may be developed as a diagnostic or screening tool for NS activity.

Dynamics of social representation in the mouse prefrontal cortex.

The prefrontal cortex (PFC) plays an important role in regulating social functions in mammals, and its dysfunction has been linked to social deficits in neurodevelopmental disorders. Yet little is known of how the PFC encodes social information and how social representations may be altered in such disorders. Here, we show that neurons in the medial PFC of freely behaving male mice preferentially respond to socially relevant olfactory cues. Population activity patterns in this region differed between social and nonsocial stimuli and underwent experience-dependent refinement. In mice lacking the autism-associated gene Cntnap2, both the categorization of sensory stimuli and the refinement of social representations were impaired. Noise levels in spontaneous population activity were higher in Cntnap2 knockouts and correlated with the degree to which social representations were disrupted. Our findings elucidate the encoding of social sensory cues in the medial PFC and provide a link between altered prefrontal dynamics and autism-associated social dysfunction.

False positive hepatitis C antibody test results in left ventricular assist device recipients: increased risk with age and transfusions.

Left ventricular assist devices (LVADs) have been successfully used in patients with heart failure. However, LVADs may trigger immune activation, leading to higher frequencies of autoantibodies. We describe the clinical, epidemiological, and laboratory characteristics of LVAD recipients with false positive hepatitis C (FPHC) serology among 39 consecutive adult LVAD recipients who bridged to heart transplantation from January 2007 to January 2013 at Montefiore Medical Center. FPHC patients were identified as those with post-LVAD positive hepatitis C ELISA antibody tests and negative confirmatory testing with hepatitis C RNA PCR and/or radioimmunoblot assay. Ten (26%) patients previously seronegative for hepatitis C were found to have FPHC after device placement. Of the 39 patients, 32 had HeartMate II devices. The mean age at LVAD placement was 55 years. FPHC correlated with older age at the time of LVAD implantation and with receipt of packed red blood cell transfusions, but not with gender, fresh frozen plasma transfusions, panel reactive antibodies, globulin fraction, rheumatoid factor, or anticardiolipin antibodies. Clinicians should be aware of this increased risk of FPHC in older LVAD patients and those more heavily transfused in order to avoid unnecessary apprehension and possible delay in transplantation. Further studies should be done to evaluate the possible relationship between transfused blood products and immunomodulation.

Oxygen sensing by primary cardiac fibroblasts: a key role of p21(Waf1/Cip1/Sdi1).

In mammalian organs under normoxic conditions, O2 concentration ranges from 12% to <0.5%, with O2 approximately 14% in arterial blood and <10% in the myocardium. During mild hypoxia, myocardial O2 drops to approximately 1% to 3% or lower. In response to chronic moderate hypoxia, cells adjust their normoxia set point such that reoxygenation-dependent relative elevation of PO2 results in perceived hyperoxia. We hypothesized that O2, even in marginal relative excess of the PO2 to which cardiac cells are adjusted, results in activation of specific signal transduction pathways that alter the phenotype and function of these cells. To test this hypothesis, cardiac fibroblasts (CFs) isolated from adult murine ventricle were cultured in 10% or 21% O2 (hyperoxia relative to the PO2 to which cells are adjusted in vivo) and were compared with those cultured in 3% O2 (mild hypoxia). Compared with cells cultured in 3% O2, cells that were cultured in 10% or 21% O2 demonstrated remarkable reversible G2/M arrest and a phenotype indicative of differentiation to myofibroblasts. These effects were independent of NADPH oxidase function. CFs exposed to high O2 exhibited higher levels of reactive oxygen species production. The molecular signature response to perceived hyperoxia included (1) induction of p21, cyclin D1, cyclin D2, cyclin G1, Fos-related antigen-2, and transforming growth factor-beta1, (2) lowered telomerase activity, and (3) activation of transforming growth factor-beta1 and p38 mitogen-activated protein kinase. CFs deficient in p21 were resistant to such O2 sensitivity. This study raises the vital broad-based issue of controlling ambient O2 during the culture of primary cells isolated from organs.

Mycobacterium avium complex olecranon bursitis resolves without antimicrobials or surgical intervention: A case report and review of the literature.

INTRODUCTION: Nontuberculous mycobacteria are an uncommon cause of septic olecranon bursitis, though cases have increasingly been described in both immunocompromised and immunocompetent hosts. Guidelines recommend a combination of surgical resection and antimicrobials for treatment. This case is the first reported case of nontuberculous mycobacterial olecranon bursitis that resolved without medical or surgical intervention. CASE PRESENTATION: A 67-year-old female developed a painless, fluctuant swelling of the olecranon bursa following blunt trauma to the elbow. Due to persistent bursal swelling, she underwent three separate therapeutic bursal aspirations, two involving intrabursal steroid injection. After the third aspiration, the bursa became erythematous and severely swollen, and bursal fluid grew Mycobacterium avium complex. Triple-drug antimycobacterial therapy was initiated, but discontinued abruptly due to a rash. Surgery was not performed. The patient was observed off antimicrobials, and gradually clinically improved with a compressive dressing. By 14 months after initial presentation, clinical exam revealed complete resolution of the previously erythematous bursal mass. DISCUSSION: This is the first reported case of nontuberculous mycobacterial olecranon bursitis managed successfully without surgery or antimicrobials. Musculoskeletal nontuberculous mycobacterial infections are challenging given the lack of clinical data about optimal duration and choice of antimicrobials or the role of surgery. Additionally, the potential toxicity and drug interactions of antimycobacterials are not insignificant and warrant close monitoring if treatment is pursued. CONCLUSION: This case raises an important clinical question of whether close observation off antimicrobials is appropriate in select cases of immunocompetent patients with localized atypical mycobacterial disease of soft tissue and skeletal structures.

Role of gallium SPECT-CT in the diagnosis of left ventricular assist device infections.

Infection remains a well-established complication after the placement of left ventricular assist devices (LVADs). Defining the extent of infection is a challenging task as there are few effective imaging modalities and no standardized guidelines regarding imaging in the diagnosis of device-related infections (DRIs). The use of gallium with single photon emission tomography-computed tomography (Ga-SPECT-CT) has not been previously reported in localizing DRIs. We reviewed the charts and images of five patients with LVADs who underwent Ga-SPECT-CT for the diagnosis of various types of DRIs. Gallium SPECT-CT further clarified the extent of infections among LVAD patients, allowing for patient-specific tailored treatments including surgical debridement. Gallium SPECT-CT is a useful tool when diagnosing LVAD infections and could potentially be the imaging modality of choice in the near future. With improved imaging studies, such as Ga-SPECT-CT, allowing for earlier and more accurate diagnoses of DRIs, the outcome of such infections is likely to improve.

Correlated brain stem and cortical evoked responses to auditory tone change.

Numerous human studies have separately observed the effects of auditory stimuli at brain stem and cortical levels, but little research has focused on possible functional coupling between these diverse brain areas. The present study recorded the cortical C-process [5] evoked by a pitch change between two successive tones, as well as the brain stem frequency-following response (FFR) evoked by each tone. The results replicated expected C-process component waveforms, including a late, negative (N2) component. FFR spectral intensity differences between the two tones were significantly correlated with N2 amplitude. These results suggest that signal processing reflected in long-latency auditory evoked response components is not exclusively a cortical phenomenon, but also depends upon patterns of neural processing occurring in brain stem pathways.

Mapping ecologically relevant social behaviours by gene knockout in wild mice.

The laboratory mouse serves as an important model system for studying gene, brain and behavioural interactions. Powerful methods of gene targeting have helped to decipher gene-function associations in human diseases. Yet, the laboratory mouse, obtained after decades of human-driven artificial selection, inbreeding, and adaptation to captivity, is of limited use for the study of fitness-driven behavioural responses that characterize the ancestral wild house mouse. Here, we demonstrate that the backcrossing of wild mice with knockout mutant laboratory mice retrieves behavioural traits exhibited exclusively by the wild house mouse, thereby unmasking gene functions inaccessible in the domesticated mutant model. Furthermore, we show that domestication had a much greater impact on females than on males, erasing many behavioural traits of the ancestral wild female. Hence, compared with laboratory mice, wild-derived mutant mice constitute an improved model system to gain insights into neuronal mechanisms underlying normal and pathological sexually dimorphic social behaviours.

Discovery of novel AKT inhibitors with enhanced anti-tumor effects in combination with the MEK inhibitor.

Tumor cells upregulate many cell signaling pathways, with AKT being one of the key kinases to be activated in a variety of malignancies. GSK2110183 and GSK2141795 are orally bioavailable, potent inhibitors of the AKT kinases that have progressed to human clinical studies. Both compounds are selective, ATP-competitive inhibitors of AKT 1, 2 and 3. Cells treated with either compound show decreased phosphorylation of several substrates downstream of AKT. Both compounds have desirable pharmaceutical properties and daily oral dosing results in a sustained inhibition of AKT activity as well as inhibition of tumor growth in several mouse tumor models of various histologic origins. Improved kinase selectivity was associated with reduced effects on glucose homeostasis as compared to previously reported ATP-competitive AKT kinase inhibitors. In a diverse cell line proliferation screen, AKT inhibitors showed increased potency in cell lines with an activated AKT pathway (via PI3K/PTEN mutation or loss) while cell lines with activating mutations in the MAPK pathway (KRAS/BRAF) were less sensitive to AKT inhibition. Further investigation in mouse models of KRAS driven pancreatic cancer confirmed that combining the AKT inhibitor, GSK2141795 with a MEK inhibitor (GSK2110212; trametinib) resulted in an enhanced anti-tumor effect accompanied with greater reduction in phospho-S6 levels. Taken together these results support clinical evaluation of the AKT inhibitors in cancer, especially in combination with MEK inhibitor.