Value-guided remapping of sensory cortex by lateral orbitofrontal cortex.

Adaptive behaviour crucially depends on flexible decision-making, which in mammals relies on the frontal cortex, specifically the orbitofrontal cortex (OFC)1-9. How OFC encodes decision variables and instructs sensory areas to guide adaptive behaviour are key open questions. Here we developed a reversal learning task for head-fixed mice, monitored the activity of neurons of the lateral OFC using two-photon calcium imaging and investigated how OFC dynamically interacts with primary somatosensory cortex (S1). Mice learned to discriminate 'go' from 'no-go' tactile stimuli10,11 and adapt their behaviour upon reversal of stimulus-reward contingency ('rule switch'). Imaging individual neurons longitudinally across all behavioural phases revealed a distinct engagement of S1 and lateral OFC, with S1 neural activity reflecting initial task learning, whereas lateral OFC neurons responded saliently and transiently to the rule switch. We identified direct long-range projections from lateral OFC to S1 that can feed this activity back to S1 as value prediction error. This top-down signal updated sensory representations in S1 by functionally remapping responses in a subpopulation of neurons that was sensitive to reward history. Functional remapping crucially depended on top-down feedback as chemogenetic silencing of lateral OFC neurons disrupted reversal learning, as well as plasticity in S1. The dynamic interaction of lateral OFC with sensory cortex thus implements computations critical for value prediction that are history dependent and error based, providing plasticity essential for flexible decision-making.

Myosin Heavy Chain as a Novel Key Modulator of Striated Muscle Resting State.

After years of intense research using structural, biological, and biochemical experimental procedures, it is clear that myosin molecules are essential for striated muscle contraction. However, this is just the tip of the iceberg of their function. Interestingly, it has been shown recently that these molecules (especially myosin heavy chains) are also crucial for cardiac and skeletal muscle resting state. In the present review, we first overview myosin heavy chain biochemical states and how they influence the consumption of ATP. We then detail how neighboring partner proteins including myosin light chains and myosin binding protein C intervene in such processes, modulating the ATP demand in health and disease. Finally, we present current experimental drugs targeting myosin ATP consumption and how they can treat muscle diseases.

Identification and management of preoperative anaemia in adults: A British Society for Haematology Guideline update.

This updated British Society for Haematology guideline provides an up-to-date literature review and recommendations regarding the identification and management of preoperative anaemia. This includes guidance on thresholds for the diagnosis of anaemia and the diagnosis and management of iron deficiency in the preoperative context. Guidance on the appropriate use of erythropoiesis-stimulating agents and preoperative transfusion is also provided.

Visual exposure enhances stimulus encoding and persistence in primary cortex.

The brain adapts to the sensory environment. For example, simple sensory exposure can modify the response properties of early sensory neurons. How these changes affect the overall encoding and maintenance of stimulus information across neuronal populations remains unclear. We perform parallel recordings in the primary visual cortex of anesthetized cats and find that brief, repetitive exposure to structured visual stimuli enhances stimulus encoding by decreasing the selectivity and increasing the range of the neuronal responses that persist after stimulus presentation. Low-dimensional projection methods and simple classifiers demonstrate that visual exposure increases the segregation of persistent neuronal population responses into stimulus-specific clusters. These observed refinements preserve the representational details required for stimulus reconstruction and are detectable in postexposure spontaneous activity. Assuming response facilitation and recurrent network interactions as the core mechanisms underlying stimulus persistence, we show that the exposure-driven segregation of stimulus responses can arise through strictly local plasticity mechanisms, also in the absence of firing rate changes. Our findings provide evidence for the existence of an automatic, unguided optimization process that enhances the encoding power of neuronal populations in early visual cortex, thus potentially benefiting simple readouts at higher stages of visual processing.

An endogenous inhibitor of angiogenesis downregulated by hypoxia in human aortic valve stenosis promotes disease pathogenesis.

Aortic valve stenosis is the most common valve disease in the western world. Central to the pathogenesis of this disease is the growth of new blood vessels (angiogenesis) within the aortic valve allowing infiltration of immune cells and development of intra-valve inflammation. Identifying the cellular mediators involved in this angiogenesis is important as this may reveal new therapeutic targets which could ultimately prevent the progression of aortic valve stenosis. Aortic valves from patients undergoing surgery for aortic valve replacement or dilation of the aortic arch were examined both ex vivo and in vitro. We now demonstrate that the anti-angiogenic protein, soluble fms-like tyrosine kinase 1 (sFlt1), a non-signalling soluble receptor for vascular endothelial growth factor, is constitutively expressed in non-diseased valves. sFlt-1 expression was, however, significantly reduced in aortic valve tissue from patients with aortic valve stenosis while protein markers of hypoxia were simultaneously increased. Exposure of primary-cultured valve interstitial cells to hypoxia resulted in a decrease in the expression of sFlt-1. We further reveal using a bioassay that siRNA knock-down of sFlt1 in valve interstitial cells directly results in a pro-angiogenic environment. Finally, incubation of aortic valves with sphingosine 1-phosphate, a bioactive lipid-mediator, increased sFlt-1 expression and inhibited angiogenesis within valve tissue. In conclusion, this study demonstrates that sFlt1 expression is directly correlated with angiogenesis in aortic valves and the observed decrease in sFlt-1 expression in aortic valve stenosis could increase valve inflammation, promoting disease progression. This could be a viable therapeutic target in treating this disease.

Predominant myosin superrelaxed state in canine myocardium with naturally occurring dilated cardiomyopathy.

Dilated cardiomyopathy (DCM) is a naturally occurring heart failure condition in humans and dogs, notably characterized by a reduced contractility and ejection fraction. As the identification of its underlying cellular and molecular mechanisms remain incomplete, the aim of the present study was to assess whether the molecular motor myosin and its known relaxed conformational states are altered in DCM. For that, we dissected and skinned thin cardiac strips from left ventricle obtained from six DCM Doberman Pinschers and six nonfailing (NF) controls. We then used a combination of Mant-ATP chase experiments and X-ray diffraction to assess both energetic and structural changes of myosin. Using the Mant-ATP chase protocol, we observed that in DCM dogs, the amount of myosin molecules in the ATP-conserving conformational state, also known as superrelaxed (SRX), is significantly increased when compared with NF dogs. This alteration can be rescued by applying EMD-57033, a small molecule activating myosin. Conversely, with X-ray diffraction, we found that in DCM dogs, there is a higher proportion of myosin heads in the vicinity of actin when compared with NF dogs (1,0 to 1,1 intensity ratio). Hence, we observed an uncoupling between energetic (Mant-ATP chase) and structural (X-ray diffraction) data. Taken together, these results may indicate that in the heart of Doberman Pinschers with DCM, myosin molecules are potentially stuck in a nonsequestered but ATP-conserving SRX state, that can be counterbalanced by EMD-57033 demonstrating the potential for a myosin-centered pharmacological treatment of DCM.NEW & NOTEWORTHY The key finding of the present study is that, in left ventricles of dogs with a naturally occurring dilated cardiomyopathy, relaxed myosin molecules favor a nonsequestered superrelaxed state potentially impairing sarcomeric contractility. This alteration is rescuable by applying a small molecule activating myosin known as EMD-57033.

Pulmonary Arterial Hypertension in Connective Tissue Diseases Beyond Systemic Sclerosis.

Pulmonary arterial hypertension (PAH) associated with connective tissue disease (CTD) (CTD-PAH) is a devastating condition that may progress rapidly to cause right ventricular dysfunction, resulting in significant morbidity and mortality. The pathobiology, epidemiology, natural history, early diagnosis, and treatment response of PAH associated with scleroderma (SSc-PAH) have been the subjects of intense research efforts over the previous decade. The success of these efforts has resulted in increased awareness and earlier detection of SSc-PAH. Practitioners are less aware of the risk of PAH associated with other CTDs; the aim of this article is to discuss the broader scope of CTD-PAH.

Treatment and outcomes of multidrug-resistant tuberculosis in Auckland, 1995-2018.

BACKGROUND: New Zealand has a low burden of tuberculosis; however, multidrug-resistant tuberculosis (MDR-TB) still represents a challenge for clinicians. This is the first description of clinical aspects of MDR-TB in New Zealand. AIMS: To evaluate the treatment and outcomes of patients with MDR-TB disease in Auckland. Secondary aims were to review the incidence and clinical characteristics of MDR-TB disease. METHODS: Clinical data were obtained for patients treated for MDR-TB at Auckland District Health Board (ADHB). RESULTS: There were 60 patients nationally with MDR-TB between 1989 and 2018; 41 (69%) of 60 patients received care at ADHB. Pulmonary infection was present in 36 (88%) of 41 patients, with 19 (46%) of 41 patients with smear-positive sputum (smear 1-2+ in 6/41, 15%; smear 3-4+ in 13/41, 32%). The median duration of treatment was 22 months (range 7.5-26) for 18 (44%) of 41 patients who completed MDR-TB treatment by August 2018. The median duration of amikacin treatment was 6 months (range 2-12) for the 23 (61%) of 38 patients in whom these data were available. All 38 patients who received treatment for MDR-TB experienced adverse effects, most commonly gastrointestinal (66%), neurological (50%), ototoxicity (47%) and psychiatric (37%). Complications of intravenous access were experienced by 10 (27%) of 37 patients. Of the 19 (46%) of 41 patients who completed treatment, 18 (95%) achieved cure. There was one case who had recurrence because of inadequate treatment, and one case who had spontaneous resolution without treatment. Seventeen (41%) patients left Auckland prior to completion of treatment, mostly to return to their country of origin (15/17, 88%). CONCLUSION: MDR-TB is uncommon in New Zealand. Treatment is frequently associated with adverse events; however, rates of cure for people completing treatment in New Zealand are high.

The diversity and specificity of functional connectivity across spatial and temporal scales.

Macroscopic neuroimaging modalities in humans have revealed the organization of brain-wide activity into distributed functional networks that re-organize according to behavioral demands. However, the inherent coarse-graining of macroscopic measurements conceals the diversity and specificity in responses and connectivity of many individual neurons contained in each local region. New invasive approaches in animals enable recording and manipulating neural activity at meso- and microscale resolution, with cell-type specificity and temporal precision down to milliseconds. Determining how brain-wide activity patterns emerge from interactions across spatial and temporal scales will allow us to identify the key circuit mechanisms contributing to global brain states and how the dynamic activity of these states enables adaptive behavior.

Clinical benefit of baseline imaging in Merkel cell carcinoma: Analysis of 584 patients.

BACKGROUND: Merkel cell carcinoma (MCC) guidelines derive from melanoma and do not recommend baseline cross-sectional imaging for most patients. However, MCC is more likely to have metastasized at diagnosis than melanoma. OBJECTIVE: To determine how often baseline imaging identifies clinically occult MCC in patients with newly diagnosed disease with and without palpable nodal involvement. METHODS: Analysis of 584 patients with MCC with a cutaneous primary tumor, baseline imaging, no evident distant metastases, and sufficient staging data. RESULTS: Among 492 patients with clinically uninvolved regional nodes, 13.2% had disease upstaged by imaging (8.9% in regional nodes, 4.3% in distant sites). Among 92 patients with clinically involved regional nodes, 10.8% had disease upstaged to distant metastatic disease. Large (>4 cm) and small (<1 cm) primary tumors were both frequently upstaged (29.4% and 7.8%, respectively). Patients who underwent positron emission tomography-computed tomography more often had disease upstaged (16.8% of 352), than those with computed tomography alone (6.9% of 231; P = .0006). LIMITATIONS: This was a retrospective study. CONCLUSIONS: In patients with clinically node-negative disease, baseline imaging showed occult metastatic MCC at a higher rate than reported for melanoma (13.2% vs <1%). Although imaging is already recommended for patients with clinically node-positive MCC, these data suggest that baseline imaging is also indicated for patients with clinically node-negative MCC because upstaging is frequent and markedly alters management and prognosis.

Narrow excision margins are appropriate for Merkel cell carcinoma when combined with adjuvant radiation: Analysis of 188 cases of localized disease and proposed management algorithm.

BACKGROUND: Merkel cell carcinoma (MCC) management typically includes surgery with or without adjuvant radiation therapy (aRT). Major challenges include determining surgical margin size and whether aRT is indicated. OBJECTIVE: To assess the association of aRT, surgical margin size, and MCC local recurrence. METHODS: Analysis of 188 MCC cases presenting without clinical nodal involvement. RESULTS: aRT-treated patients tended to have higher-risk tumors (larger diameter, positive microscopic margins, immunosuppression) yet had fewer local recurrences (LRs) than patients treated with surgery only (1% vs 15%; P = .001). For patients who underwent surgery alone, 7 of 35 (20%) treated with narrow margins (defined as ≤1.0 cm) developed LR, whereas 0 of 13 patients treated with surgical margins greater than 1.0 cm developed LR (P = .049). For aRT-treated patients, local control was excellent regardless of surgical margin size; only 1% experienced recurrence in each group (1 of 70 with narrow margins ≤1 cm and 1 of 70 with margins >1 cm; P = .56). LIMITATIONS: This was a retrospective study. CONCLUSIONS: Among patients treated with aRT, local control was superb even if significant risk factors were present and margins were narrow. We propose an algorithm for managing primary MCC that integrates risk factors and optimizes local control while minimizing morbidity.

Retropubic mid-urethral slings and de novo urinary urgency and frequency: The role of retropubic hematomas.

AIMS: This is a prospective cohort study comparing de novo lower urinary tract symptoms (LUTS) in subjects undergoing a retropubic mid-urethral sling who either did or did not develop a postoperative retropubic hematoma within 6 weeks of surgery. The secondary objective was to measure the incidence and prevalence of retropubic hematomas, and subject characteristics associated with retropubic hematomas. METHODS: Eligible subjects were recruited before undergoing a retropubic mid-urethral sling with or without concurrent pelvic reconstructive surgery. Validated urinary symptom questionnaires were completed before surgery and at 6 weeks postoperatively. An abdominal ultrasound was used to establish baseline lower urinary tract imaging. Ultrasound was repeated immediately after surgery and 6 weeks later to assess for the presence of retropubic hematomas. RESULTS: Ninety-four subjects were enrolled. Baseline urgency and frequency were measured in 35% (33/93) of subjects. At 6 weeks postoperatively, 2% (1/52) had de novo LUTS which were not associated with a retropubic hematoma at any time. Immediately after surgery, the incidence of retropubic hematomas was 17% (16/94) while the prevalence of retropubic hematomas 6 weeks after surgery was 4% (3/75). There was no significant difference in the change in hemoglobin before and after surgery between those with and without postoperative retropubic hematomas. CONCLUSIONS: There is no significant association with de novo LUTS and retropubic hematomas. Though there is a 17% incidence of retropubic hematomas detected immediately after surgery, those with hematomas who were not lost to follow-up resolved by the 6-week postoperative visit and is of unclear clinical significance.

Cortical Excitation:Inhibition Imbalance Causes Abnormal Brain Network Dynamics as Observed in Neurodevelopmental Disorders.

Abnormal brain development manifests itself at different spatial scales. However, whether abnormalities at the cellular level can be diagnosed from network activity measured with functional magnetic resonance imaging (fMRI) is largely unknown, yet of high clinical relevance. Here a putative mechanism reported in neurodevelopmental disorders, that is, excitation-to-inhibition ratio (E:I), was chemogenetically increased within cortical microcircuits of the mouse brain and measured via fMRI. Increased E:I caused a significant "reduction" of long-range connectivity, irrespective of whether excitatory neurons were facilitated or inhibitory Parvalbumin (PV) interneurons were suppressed. Training a classifier on fMRI signals, we were able to accurately classify cortical areas exhibiting increased E:I. This classifier was validated in an independent cohort of Fmr1y/- knockout mice, a model for autism with well-documented loss of parvalbumin neurons and chronic alterations of E:I. Our findings demonstrate a promising novel approach towards inferring microcircuit abnormalities from macroscopic fMRI measurements.

A review of epigenetic regulation in wound healing: Implications for the future of wound care.

Epigenetic regulatory mechanisms are essential for maintaining skin homeostasis and aid in the processes of wound healing. The nucleus co-ordinates gene expression using epigenetic regulatory mechanisms based on distinct chromatin structural states and their remodeling. These include DNA methylation and hydroxymethylation, post-translational histone modifications, ATP-dependent chromatin remodeling and higher-order chromatin structure and 3D genome organization. Epigenetic pathways play a key role in co-ordinating the behavior and activity of the multitude of cell types seen during skin repair, and research is now focusing on how wound healing can be modulated by altering the activity of certain reparative genes. Herein, we aim to highlight recent advances in understanding epigenetic regulatory mechanisms, with particular reference to those involved in keratinocyte and fibroblast biology. We also propose future directions for exploration of epigenetic mechanisms, and their potential clinical applications in acute wound care.

Screening for anaplastic lymphoma kinase (ALK) gene rearrangements in non-small-cell lung cancer in New Zealand.

BACKGROUND: Lung cancer is a major cause of death in New Zealand. In recent years, targeted therapies have improved outcomes. AIM: To determine the uptake of anaplastic lymphoma kinase (ALK) testing, and the prevalence, demographic profile and outcomes of ALK-positive non-small-cell lung cancer (NSCLC), in New Zealand, where no national ALK-testing guidelines or subsidised ALK tyrosine kinase inhibitor (TKI) therapies are available. METHODS: A population-based observational study reviewed databases to identify patients presenting with non-squamous NSCLC over 6.5 years in northern New Zealand. We report the proportion tested for ALK gene rearrangements and the results. NSCLC samples tested by fluorescence in situ hybridisation were retested by next generation sequencing and ALK immunohistochemistry. A survival analysis compared ALK-positive patients treated or not treated with ALK TKI therapy. RESULTS: From a total of 3130 patients diagnosed with non-squamous NSCLC, 407 (13%) were tested for ALK gene rearrangements, and patient selection was variable and inequitable. Among those tested, 34 (8.4%) had ALK-positive NSCLC. ALK-positive disease was more prevalent in younger versus older patients, non-smokers versus smokers and in Maori, Pacific or Asian ethnic groups than in New Zealand Europeans. Fluorescence in situ hybridisation, ALK immunohistochemistry and next generation sequencing showed broad concordance for detecting ALK-positive disease under local testing conditions. Among patients with ALK-positive metastatic NSCLC, those treated with ALK TKI survived markedly longer than those not treated with ALK TKI (median overall survival 5.12 vs 0.55 years). CONCLUSION: Lung cancer outcomes in New Zealand may be improved by providing national guidelines and funding policy for ALK testing and access to subsidised ALK TKI therapy.

Stimulus-induced visual cortical networks are recapitulated by spontaneous local and interareal synchronization.

Intrinsic covariation of brain activity has been studied across many levels of brain organization. Between visual areas, neuronal activity covaries primarily among portions with similar retinotopic selectivity. We hypothesized that spontaneous interareal coactivation is subserved by neuronal synchronization. We performed simultaneous high-density electrocorticographic recordings across the dorsal aspect of several visual areas in one hemisphere in each of two awake monkeys to investigate spatial patterns of local and interareal synchronization. We show that stimulation-induced patterns of interareal coactivation were reactivated in the absence of stimulation for the visual quadrant covered. Reactivation occurred through both interareal cofluctuation of local activity and interareal phase synchronization. Furthermore, the trial-by-trial covariance of the induced responses recapitulated the pattern of interareal coupling observed during stimulation, i.e., the signal correlation. Reactivation-related synchronization showed distinct peaks in the theta, alpha, and gamma frequency bands. During passive states, this rhythmic reactivation was augmented by specific patterns of arrhythmic correspondence. These results suggest that networks of intrinsic covariation observed at multiple levels and with several recording techniques are related to synchronization and that behavioral state may affect the structure of intrinsic dynamics.

Evidence on public health interventions in humanitarian crises.

Recognition of the need for evidence-based interventions to help to improve the effectiveness and efficiency of humanitarian responses has been increasing. However, little is known about the breadth and quality of evidence on health interventions in humanitarian crises. We describe the findings of a systematic review with the aim of examining the quantity and quality of evidence on public health interventions in humanitarian crises to identify key research gaps. We identified 345 studies published between 1980 and 2014 that met our inclusion criteria. The quantity of evidence varied substantially by health topic, from communicable diseases (n=131), nutrition (n=77), to non-communicable diseases (n=8), and water, sanitation, and hygiene (n=6). We observed common study design and weaknesses in the methods, which substantially reduced the ability to determine causation and attribution of the interventions. Considering the major increase in health-related humanitarian activities in the past three decades and calls for a stronger evidence base, this paper highlights the limited quantity and quality of health intervention research in humanitarian contexts and supports calls to scale up this research.

Socioeconomic deprivation is not associated with reduced survival of lung transplant recipients.

BACKGROUND: Important risk factors for long-term survival of lung transplant (LT) recipients are infection, acute graft rejection (AR) and chronic lung allograft dysfunction (CLAD). Socioeconomic deprivation (SED) is associated with increased graft failure rate after heart and kidney transplantation, but has not been investigated in LT recipients. The aim of this study was to evaluate an association between LT recipients' SED status and development of AR, CLAD, and long-term survival. METHODS: This was a retrospective cohort study. Over a 23 y period, 233 patients were identified from the Auckland City Hospital Lung Transplant Registry, Auckland, New Zealand. All patients were divided into two groups according to the 2013 New Zealand Deprivation Index Score. RESULTS: The incidence of AR in the higher SED group was 34.0/100 person-y (95% confidence interval [CI]: 24.7-46.7/100 person-y) and in the lower SED group 40.2/100 person-y (95% CI: 33.5-48.3/100 person-y) (P = 0.373). The incidence of CLAD in the higher SED group was 10.7/100 person-y (95% CI: 6.2-18.4/100 person-y) and 9.3 (6.9-12.5/100 person-y) in the lower SED group (P = 0.645). Mortality in the higher SED group was 12.9/100 person-y (95% CI: 9.2-17.9/100 person-y) and 12.4/100 person-y (95% CI: 10.0-15.3/100 person-y) in the lower SED group (P = 0.834). CONCLUSIONS: SED status of LT recipients in New Zealand has no negative effect on development of AR, CLAD, and patients' survival.

Ethnicity, socioeconomic status and the severity and course of non-cystic fibrosis bronchiectasis.

BACKGROUND AND AIMS: This study evaluated whether there are ethnic factors which affect the severity and progression of bronchiectasis in our adult multi-ethnic population in Auckland, New Zealand. METHODS: Clinical records were reviewed from patients attending the outpatient facilities of our institution between 2007 and 2010. Data collected included demographics, clinical features, smoking status, self-reported ethnicity, socioeconomic status (NZDep), pulmonary function and sputum microbiology. RESULTS: A total of 437 patients was identified: median age 65 years, 66% female, mean forced expiratory volume in the first second (FEV1 ) 62.4% predicted, and 10.5% of patients had recurrent growth of Pseudomonas aeruginosa. Patients of Maori and Pacific ethnicity were overrepresented compared to the institution population catchment and had more severe impairment of lung function: mean % predicted FEV1 for Pacific 52.0, Maori 58.6, European 68.6, Asian 64.2 (P < 0.0001). This was independent of socioeconomic status. However, no overall decline was seen in serial lung function measurements, either across the whole cohort or in any particular ethnic group. CONCLUSIONS: Patients of Maori and Pacific ethnicity are both overrepresented and have more severe bronchiectasis in this cohort, independent of socioeconomic status. Ethnicity did not predict decline in pulmonary function. Further studies into genetic predisposition to bronchiectasis in Maori or Pacific people may be warranted.

αCP binding to a cytosine-rich subset of polypyrimidine tracts drives a novel pathway of cassette exon splicing in the mammalian transcriptome.

Alternative splicing (AS) is a robust generator of mammalian transcriptome complexity. Splice site specification is controlled by interactions of cis-acting determinants on a transcript with specific RNA binding proteins. These interactions are frequently localized to the intronic U-rich polypyrimidine tracts (PPT) located 5' to the majority of splice acceptor junctions. αCPs (also referred to as polyC-binding proteins (PCBPs) and hnRNPEs) comprise a subset of KH-domain proteins with high affinity and specificity for C-rich polypyrimidine motifs. Here, we demonstrate that αCPs promote the splicing of a defined subset of cassette exons via binding to a C-rich subset of polypyrimidine tracts located 5' to the αCP-enhanced exonic segments. This enhancement of splice acceptor activity is linked to interactions of αCPs with the U2 snRNP complex and may be mediated by cooperative interactions with the canonical polypyrimidine tract binding protein, U2AF65. Analysis of αCP-targeted exons predicts a substantial impact on fundamental cell functions. These findings lead us to conclude that the αCPs play a direct and global role in modulating the splicing activity and inclusion of an array of cassette exons, thus driving a novel pathway of splice site regulation within the mammalian transcriptome.