Familial atrial fibrillation mutation M1875T-SCN5A increases early sodium current and dampens the effect of flecainide.

AIMS: Atrial fibrillation (AF) is the most common cardiac arrhythmia. Pathogenic variants in genes encoding ion channels are associated with familial AF. The point mutation M1875T in the SCN5A gene, which encodes the α-subunit of the cardiac sodium channel Nav1.5, has been associated with increased atrial excitability and familial AF in patients. METHODS AND RESULTS: We designed a new murine model carrying the Scn5a-M1875T mutation enabling us to study the effects of the Nav1.5 mutation in detail in vivo and in vitro using patch clamp and microelectrode recording of atrial cardiomyocytes, optical mapping, electrocardiogram, echocardiography, gravimetry, histology, and biochemistry. Atrial cardiomyocytes from newly generated adult Scn5a-M1875T+/- mice showed a selective increase in the early (peak) cardiac sodium current, larger action potential amplitude, and a faster peak upstroke velocity. Conduction slowing caused by the sodium channel blocker flecainide was less pronounced in Scn5a-M1875T+/- compared to wildtype atria. Overt hypertrophy or heart failure in Scn5a-M1875T+/- mice could be excluded. CONCLUSION: The Scn5a-M1875T point mutation causes gain-of-function of the cardiac sodium channel. Our results suggest increased atrial peak sodium current as a potential trigger for increased atrial excitability.

Factors influencing healthcare professionals' confidence in vaccination in Europe: a literature review.

Health-care professionals (HCPs) have a fundamental role in vaccination, their own beliefs and attitudes affecting both their uptake and recommendation of vaccines. This literature review (n = 89) summarises evidence on HCPs' perceptions of the risks and benefits of vaccination, trust, and perceptions of mandatory vaccination in Europe. HCPs across studies believed that vaccination is important to protect themselves and their patients. However, beliefs that some diseases such as influenza are less risky were reported by some HCPs as a reason for not getting vaccinated. Concerns about both short- and long-term side effects were identified among HCPs in most studies, such as those affecting the immune or neurological system. Mistrust toward health authorities and pharmaceutical industry was reported in some studies. The question of mandatory vaccination revealed mixed opinions, with some favoring self-determination and others viewing vaccination as a duty. This review highlights key factors influencing HCPs' confidence in vaccination in Europe.

Accelerated cortical thinning and volume reduction over time in young people at high genetic risk for bipolar disorder.

BACKGROUND: Bipolar disorder (BD) is a familial psychiatric disorder associated with frontotemporal and subcortical brain abnormalities. It is unclear whether such abnormalities are present in relatives without BD, and little is known about structural brain trajectories in those at risk. METHOD: Neuroimaging was conducted at baseline and at 2-year follow-up interval in 90 high-risk individuals with a first-degree BD relative (HR), and 56 participants with no family history of mental illness who could have non-BD diagnoses. All 146 subjects were aged 12-30 years at baseline. We examined longitudinal change in gray and white matter volume, cortical thickness, and surface area in the frontotemporal cortex and subcortical regions. RESULTS: Compared to controls, HR participants showed accelerated cortical thinning and volume reduction in right lateralised frontal regions, including the inferior frontal gyrus, lateral orbitofrontal cortex, frontal pole and rostral middle frontal gyrus. Independent of time, the HR group had greater cortical thickness in the left caudal anterior cingulate cortex, larger volume in the right medial orbitofrontal cortex and greater area of right accumbens, compared to controls. This pattern was evident even in those without the new onset of psychopathology during the inter-scan interval. CONCLUSIONS: This study suggests that differences previously observed in BD are developing prior to the onset of the disorder. The pattern of pathological acceleration of cortical thinning is likely consistent with a disturbance of molecular mechanisms responsible for normal cortical thinning. We also demonstrate that neuroanatomical differences in HR individuals may be progressive in some regions and stable in others.

A Review of Inflammatory Bowel Disease: A Model of Microbial, Immune and Neuropsychological Integration.

Objective: Inflammatory bowel diseases (IBDs) are complex chronic inflammatory disorders of the gastro-intestinal (GI) tract with uncertain etiology. IBDs comprise two idiopathic disorders: Crohn's disease (CD) and ulcerative colitis (UC). The aetiology, severity and progression of such disorders are still poorly understood but thought to be influenced by multiple factors (including genetic, environmental, immunological, physiological, psychological factors and gut microbiome) and their interactions. The overarching aim of this review is to evaluate the extent and nature of the interrelationship between these factors with the disease course. A broader conceptual and longitudinal framework of possible neuro-visceral integration, core microbiome analysis and immune modulation assessment may be useful in accurately documenting and characterizing the nature and temporal continuity of crosstalk between these factors and the role of their interaction (s) in IBD disease activity. Characterization of these interactions holds the promise of identifying novel diagnostic, interventions, and therapeutic strategies. Material and Methods: A search of published literature was conducted by exploring PubMed, EMBASE, MEDLINE, Medline Plus, CDSR library databases. Following search terms relating to key question were set for the search included: "Inflammatory bowel diseases," "gut microbiota," "psychological distress and IBD," "autonomic reactivity and IBD," "immune modulation," "chronic inflammation," "gut inflammation," "enteric nervous system," "gut nervous system," "Crohn's disease," "Ulcerative colitis", "depression and IBD", "anxiety and IBD", "quality of life in IBD patients," "relapse in IBDs," "remission in IBDs," "IBD disease activity," "brain-gut-axis," "microbial signature in IBD," "validated questionnaires in IBD," "IBD activity indices," "IBD aetiology," "IBDs and stress," "epidemiology of IBDs", "autonomic nervous system and gut inflammation", "IBD and environment," "genetics of IBDs," "pathways of immune response in IBDs," "sleep disturbances in IBD," "hypothalamic-pituitary-adrenal axis (HPA)," "sympatho-adrenal axis," "CNS and its control of gut function" "mucosal immune response," "commensal and pathogenic bacteria in the gut," "innate and adaptive immunity." Studies evaluating any possible associations between gut microbiome, psychological state, immune modulation, and autonomic function with IBDs were identified. Commonly cited published literatures with high quality research methodology/results and additional articles from bibliographies of recovered papers were examined and included where relevant. Results: Although there is a substantial literature identifying major contributing factors with IBD, there has been little attempt to integrate some factors over time and assess their interplay and relationship with IBD disease activity. Such contributing factors include genetic and environmental factors, gut microbiota composition and function, physiological factors, psychological state and gut immune response. Interdependences are evident across psychological and biological factors and IBD disease activity. Although from the available evidence, it is implausible that a single explanatory model could elucidate the interplay between such factors and the disease course as well as the sequence of the effect during the pathophysiology of IBD. Conclusion: Longitudinal monitoring of IBD patients and integrating data related to the contributing/risk factors including psychological state, physiological conditions, inflammatory/immune modulations, and microbiome composition/function, could help to explain how major factors associate and interrelate leading to exacerbation of symptoms and disease activity. Identifying the temporal trajectory of biological and psychosocial disturbances may also help to assess their effects and interdependence on individuals' disease status. Moreover, this allows greater insight into understanding the temporal progressions of subclinical events as potential ground for disease severity in IBD. Furthermore, understanding the interaction between these risk factors may help better interventions in controlling the disease, reducing the costs related to disease management, further implications for clinical practice and research approaches in addition to improving patients' mental health and quality of life.

Differentiating clinical and non-clinical depression: a heuristic study offering a template for extension studies.

OBJECTIVE: To differentiate clinical and non-clinical depression via a set of symptoms. METHODS: A sample of 140 patients attending a clinical service for those with mood disorders together with 40 subjects denying ever experiencing a clinical episode of depression were compared, with participants completing a questionnaire capturing many symptoms of depression as well as illness correlates. RESULTS: A latent class analysis of symptom data identified two classes and with class assignment corresponding strongly with initial clinical vs. non-clinical assignment. Univariate analyses identified the extent to which individual symptoms contributed to differentiation. Study data suggested DSM criteria that would benefit from re-writing or of reassignment. Two models for classifying clinical depression were generated. The first involved individuals feeling hopeless and also being suicidal or at risk of self-harm. The second involved a symptom set corresponding to DSM-5 criteria but with only five making significant independent contributions to diagnostic differentiation. CONCLUSION: The study is heuristic in offering a strategy for more precisely differentiating clinical and non-clinical depression in more representative samples, so allowing resolution of key features, and determining whether a monothetic or polythetic diagnostic symptom criterion model is optimal.

Refined diagnostic criteria for the bipolar disorders: phase two of the AREDOC project.

OBJECTIVE: As limitations exist across DSM criteria sets for defining and differentiating the bipolar disorders generally and their component bipolar I (BP-1) and bipolar II (BP-II) sub-types, we sought to generate empirically based criteria. METHOD: We formed an international Task Force (TF) comprising members with bipolar disorder expertise, and who recruited 74 patients with a TF-diagnosed bipolar I and 104 with a bipolar II condition (with patients responding to definitional queries and symptom questionnaires), while 33 unipolar depressed patients recruited by the first author also completed the symptom questionnaire. A factor analysis sought to determine granular hypo/manic constructs. RESULTS: The bipolar disorder subjects strongly affirmed a new general definition of a bipolar disorder (capturing both manic and hypomanic episodes). While DSM-5 requires impaired functioning, we established that a high percentage of individuals with a BP-I or a BP-II disorder reported improved functioning and therefore modified this criterion. Analyses identified syptoms with differential high rates in individuals with bipolar disorder and its sub-types (and thus not simply capturing happiness), while a factor analysis generated seven symptom constructs both linked with and differing from DSM-5 bipolar symptom criteria. CONCLUSION: This second-stage report details a new set of criteria for differentiating the bipolar disorders from unipolar depressive conditions, while arguing for BP-I and BP-II disorders being differentiated principally by the respective presence or absence of psychotic features. Future studies will evaluate whether further modifications are required and examine for differential treatment benefits for those with a BP-I versus a BP-II condition.

A population study of prolonged grief in refugees.

AIMS: Despite the frequency that refugees suffer bereavement, there is a dearth of research into the prevalence and predictors of problematic grief reactions in refugees. To address this gap, this study reports a nationally representative population-based study of refugees to determine the prevalence of probable prolonged grief disorder (PGD) and its associated problems. METHODS: This study recruited participants from the Building a New Life in Australia (BNLA) prospective cohort study of refugees admitted to Australia between October 2013 and February 2014. The current data were collected in 2015-2016, and comprised 1767 adults, as well as 411 children of the adult respondents. Adult refugees were assessed for trauma history, post-migration difficulties, probable PGD, post-traumatic stress disorder (PTSD) and mental illness. Children were administered the Strengths and Difficulties Questionnaire. RESULTS: In this cohort, 38.1% of refugees reported bereavement, of whom 15.8% reported probable PGD; this represents 6.0% of the entire cohort. Probable PGD was associated with a greater likelihood of mental illness, probable PTSD, severe mental illness, currently unemployed and reported disability. Children of refugees with probable PGD reported more psychological difficulties than those whose parents did not have probable PGD. Probable PGD was also associated with the history of imprisonment, torture and separation from family. Only 56.3% of refugees with probable PGD had received psychological assistance. CONCLUSIONS: Bereavement and probable PGD appear highly prevalent in refugees, and PGD seems to be associated with disability in the refugees and psychological problems in their children. The low rate of access to mental health assistance for these refugees highlights that there is a need to address this issue in refugee populations.

A Protocol for Transverse Cardiac Slicing and Optical Mapping in Murine Heart.

Thin living tissue slices have recently emerged as a new tissue model for cardiac electrophysiological research. Slices can be produced from human cardiac tissue, in addition to small and large mammalian hearts, representing a powerful in vitro model system for preclinical and translational heart research. In the present protocol, we describe a detailed mouse heart transverse slicing and optical imaging methodology. The use of this technology for high-throughput optical imaging allows study of electrophysiology of murine hearts in an organotypic pseudo two-dimensional model. The slices are cut at right angles to the long axis of the heart, permitting robust interrogation of transmembrane potential (Vm) and calcium transients (CaT) throughout the entire heart with exceptional regional precision. This approach enables the use of a series of slices prepared from the ventricles to measure Vm and CaT with high temporal and spatial resolution, allowing (i) comparison of successive slices which form a stack representing the original geometry of the heart; (ii) profiling of transmural and regional gradients in Vm and CaT in the ventricle; (iii) characterization of transmural and regional profiles of action potential and CaT alternans under stress (e.g., high frequency pacing or ß-adrenergic stimulation) or pathological conditions (e.g., hypertrophy). Thus, the protocol described here provides a powerful platform for innovative research on electrical and calcium handling heterogeneity within the heart. It can be also combined with optogenetic technology to carry out optical stimulation; aiding studies of cellular Vm and CaT in a cell type specific manner.

Transverse cardiac slicing and optical imaging for analysis of transmural gradients in membrane potential and Ca2+ transients in murine heart.

KEY POINTS: A robust cardiac slicing approach was developed for optical mapping of transmural gradients in transmembrane potential (Vm ) and intracellular Ca2+ transient (CaT) of murine heart. Significant transmural gradients in Vm and CaT were observed in the left ventricle. Frequency-dependent action potentials and CaT alternans were observed in all ventricular regions with rapid pacing, with significantly greater incidence in the endocardium than epicardium. The observations demonstrate the feasibility of our new approach to cardiac slicing for systematic analysis of intrinsic transmural and regional gradients in Vm and CaT. ABSTRACT: Transmural and regional gradients in membrane potential and Ca2+ transient in the murine heart are largely unexplored. Here, we developed and validated a robust approach which combines transverse ultra-thin cardiac slices and high resolution optical mapping to enable systematic analysis of transmural and regional gradients in transmembrane potential (Vm ) and intracellular Ca2+ transient (CaT) across the entire murine ventricles. The voltage dye RH237 or Ca2+ dye Rhod-2 AM were loaded through the coronary circulation using a Langendorff perfusion system. Short-axis slices (300 µm thick) were prepared from the entire ventricles (from the apex to the base) by using a high-precision vibratome. Action potentials (APs) and CaTs were recorded with optical mapping during steady-state baseline and rapid pacing. Significant transmural gradients in Vm and CaT were observed in the left ventricle, with longer AP duration (APD50 and APD75 ) and CaT duration (CaTD50 and CaTD75 ) in the endocardium compared with that in the epicardium. No significant regional gradients were observed along the apico-basal axis of the left ventricle. Interventricular gradients were detected with significantly shorter APD50 , APD75 and CaTD50 in the right ventricle compared with left ventricle and ventricular septum. During rapid pacing, AP and CaT alternans were observed in most ventricular regions, with significantly greater incidence in the endocardium in comparison with epicardium. In conclusion, these observations demonstrate the feasibility of our new approach to cardiac slicing for systematic analysis of intrinsic transmural and regional gradients in Vm and CaT in murine ventricular tissue.

Long-term clinical impact of permanent cardiac pacing after transcatheter aortic valve implantation with the CoreValve prosthesis: a single center experience.

Aims: To determine the impact of permanent cardiac pacing after transcatheter aortic valve implantation (TAVI) with the CoreValveTM prosthesis in terms of all-cause mortality and morbidity [rehospitalizations for heart failure (HF) or stroke] at the long-term follow-up. Methods and results: The prospective analysis comprised 259 patients (138 women, 53.3%, age 78 ± 6 years) treated by a CoreValveTM prosthesis from April 2008 to December 2015. Forty-two patients were excluded for analysis: 9 with pre-existing permanent pacemaker (PPM) implantation, 19 who required a PPM during the follow-up and 14 patients because of hospital mortality during or after the CoreValveTM prosthesis implantation procedure. The remaining 217 patients were divided in two groups: Group-1 included those patients who required a PPM immediately after TAVI, and Group-2 included those patients who did not require permanent cardiac pacing at the long-term follow-up. Patients received follow-up at 1-month, 6-months, 12-months, and yearly thereafter. A total of 39 patients required a PPM immediately after TAVI (15.0%), but 178 patients (68.7%) did not. The mean follow-up was 37 ± 27 months (range 3-99 months) in both groups. There was no difference between the two groups in terms of all-cause mortality (52.6% vs. 56.8%, P = 0.125; HR 1.22 [0.87-1.77, 95% CI]), or stroke (13.3% vs. 15.1% P = 0.842; HR 1.12 [0.37-3.32, 95% CI]). However, patients who underwent PPM implantation developed an increase in readmissions for HF (21.1% vs. 31.9%, P = 0.015; HR 1.82 [1.23-3.92, 95% CI]). Conclusion: Patients requiring a PPM after TAVI did not have an increase in mortality, or an increase in the likelihood of developing a stroke at a long-term follow-up. However, this subgroup of patients showed an increase in rehospitalization due to HF at medium- and long-term follow-up.

The influence of TNF alpha -308 G/A polymorphism on oxidative stress in patients with chronic lymphocytic leukemia.

The aim of this study was to examine the association of TNF-α-308G/A polymorphism with CLL and influence on oxidative stress parameters.Significant difference in the genotype and allele distribution was obtained in TNFA subgroup of patients.Significantly higher GPx activity and TBARS and lower catalase activity were detected in CLL.Significantly higher catalase and lower GPx activities were detected in PBMC of TNFG compared to TNFA subgroup, while TBARS were higher in TNFA.Oxidative stress in CLL patients highly correlates with the presence of TNFA subgroup. Increased TBARS, GPx and decreased catalase activity are associated with TNF-α-308A allele containing genotypes.

Targeting and transforming major depression.

OBJECTIVE: To detail limitations to the construct of 'major depression', argue for repositioning it as a proxy for 'clinical depression' and then operationalize it and its principal constituent depressive subtypes, while preserving the DSM criteria-based format. METHOD: We summarize limitations to major depression being viewed as a diagnostic entity. Data from 391 clinically depressed patients were analysed to identify high-prevalence non-specific depressive symptoms to define 'clinical depression' as well as the features showing specificity to a melancholic depressive subtype. RESULTS: We identified a set of high-prevalence and generalized symptoms for defining clinical depression and with many being current criteria for major depression. We also developed a refined set of melancholic features and with their underlying distributions generating two classes that correlated strongly with clinical diagnoses of a melancholic or non-melancholic depression, thus validating its capacity to so differentiate. We append criteria sets for diagnosing clinical depression and its principal diagnostic subtypes (psychotic, melancholic and non-melancholic). CONCLUSION: This heuristic study reframes and modifies major depression's criteria set to define a domain of clinical depression with additional criteria and then allowing the delineation of three diagnostic subtypes. If this paradigm shift is accepted and further refined, greater precision in diagnosis, treatment and research would be anticipated.

The longitudinal relationship between post-traumatic stress disorder and perceived social support in survivors of traumatic injury.

BACKGROUND: Although perceived social support is thought to be a strong predictor of psychological outcomes following trauma exposure, the temporal relationship between perceived positive and negative social support and post-traumatic stress disorder (PTSD) symptoms has not been empirically established. This study investigated the temporal sequencing of perceived positive social support, perceived negative social support, and PTSD symptoms in the 6 years following trauma exposure among survivors of traumatic injury. METHOD: Participants were 1132 trauma survivors initially assessed upon admission to one of four Level 1 trauma hospitals in Australia after experiencing a traumatic injury. Participants were followed up at 3 months, 12 months, 24 months, and 6 years after the traumatic event. RESULTS: Latent difference score analyses revealed that greater severity of PTSD symptoms predicted subsequent increases in perceived negative social support at each time-point. Greater severity of PTSD symptoms predicted subsequent decreases in perceived positive social support between 3 and 12 months. High levels of perceived positive or negative social support did not predict subsequent changes in PTSD symptoms at any time-point. CONCLUSIONS: Results highlight the impact of PTSD symptoms on subsequent perceived social support, regardless of the type of support provided. The finding that perceived social support does not influence subsequent PTSD symptoms is novel, and indicates that the relationship between PTSD and perceived social support may be unidirectional.

Assessment of traffic noise levels in urban areas using different soft computing techniques.

Available traffic noise prediction models are usually based on regression analysis of experimental data, and this paper presents the application of soft computing techniques in traffic noise prediction. Two mathematical models are proposed and their predictions are compared to data collected by traffic noise monitoring in urban areas, as well as to predictions of commonly used traffic noise models. The results show that application of evolutionary algorithms and neural networks may improve process of development, as well as accuracy of traffic noise prediction.

Interhemispheric white matter integrity in young people with bipolar disorder and at high genetic risk.

BACKGROUND: White matter (WM) impairments have been reported in patients with bipolar disorder (BD) and those at high familial risk of developing BD. However, the distribution of these impairments has not been well characterized. Few studies have examined WM integrity in young people early in the course of illness and in individuals at familial risk who have not yet passed the peak age of onset. METHOD: WM integrity was examined in 63 BD subjects, 150 high-risk (HR) individuals and 111 participants with no family history of mental illness (CON). All subjects were aged 12 to 30 years. RESULTS: This young BD group had significantly lower fractional anisotropy within the genu of the corpus callosum (CC) compared with the CON and HR groups. Moreover, the abnormality in the genu of the CC was also present in HR participants with recurrent major depressive disorder (MDD) (n = 16) compared with CON participants. CONCLUSIONS: Our findings provide important validation of interhemispheric abnormalities in BD patients. The novel finding in HR subjects with recurrent MDD - a group at particular risk of future hypo/manic episodes - suggests that this may potentially represent a trait marker for BD, though this will need to be confirmed in longitudinal follow-up studies.

The Validation Study of Neurofilament Heavy Chain and 8-hydroxy-2'-deoxyguanosine as Plasma Biomarkers of Clinical/Paraclinical Activity in First and Relapsing-Remitting Demyelination Acute Attacks.

Although current evidence mainly suggests immunopathogenesis of demyelination and neurodegeneration in multiple sclerosis (MS), there are results which document the importance of other factors, such as oxidative stress and its mediated injuries. The oxidative stress intensity in axonal damage during acute demyelination is little known. We performed this study as a cross-sectional biomarker validation study in order to evaluate the parameters of axonal damage (phosphorylated neurofilaments heavy chain (pNF-H)) and oxidative stress (8-hydroxy-2'-deoxyguanosine (8-OHdG)) in plasma of patients with initial and relapsing-remitting demyelination attacks, defined as clinically isolated syndrome (CIS) and relapsing-remitting multiple sclerosis (RRMS); and the correlations between these parameters and biological (index of blood brain barrier (BBB) permeability), clinical (index of disease progression), and radiological (T1-Gd-enhancing lesion volume) activities of disease. Both parameters were increased in CIS and RRMS compared to control subjects (p < 0.05). The positive correlations were observed between 8-OHdG values and index of BBB permeability, clinical severity of disease, and demyelinated brain lesion volume, in CIS group (r > 0.50; p < 0.05). Similar correlations were obtained between pNF-H values and the above parameters, as well as the index of disease progression, in RRMS group (r > 0.30; p < 0.05). There was a significant correlation between values of 8-OHdG and pNF-H only in CIS group, r = 0.52, p < 0.05. While the plasma values of 8-OHdG reflect the degree of acute demyelination in CIS, pNF-H values reflect that in RRMS. The obtained results must be reevaluated in similar prospective studies related to their prognostic values.

Are there subtypes of bipolar depression?

OBJECTIVE: To investigate for subtypes of bipolar depression using latent class analysis (LCA). METHOD: Participants were recruited through a bipolar disorder (BD) clinic. LCA was undertaken using: (i) symptoms reported on the SCID-IV for the most severe lifetime depressive episode; (ii) lifetime illness features such as age at first depressive and hypo/manic episodes; and (iii) family history of BD and unipolar depression. To explore the validity of any demonstrated 'classes', clinical, demographic and treatment correlates were investigated. RESULTS: A total of 243 BD subjects (170 with BD-I and 73 with BD-II) were included. For the combined sample, we found two robust LCA solutions, with two and three classes respectively. There were no consistent solutions when the BD-I and BD-II samples were considered separately. Subjects in class 2 of the three-class solution (characterised by anxiety, insomnia, reduced appetite/weight loss, irritability, psychomotor retardation, suicidal ideation, guilt, worthlessness and evening worsening) were significantly more likely to be in receipt of government financial support, suggesting a particularly malign pattern of symptoms. CONCLUSION: Our study suggests the existence of two or three distinct classes of bipolar depression and a strong association with functional outcome.

Placebo-controlled pilot trial testing dose titration and intravenous, intramuscular and subcutaneous routes for ketamine in depression.

OBJECTIVE: This pilot study assessed the feasibility, efficacy and safety of an individual dose-titration approach, and of the intravenous (IV), intramuscular (IM) and subcutaneous (SC) routes for treating depression with ketamine. METHOD: Fifteen treatment-refractory depressed participants received ketamine or midazolam (control treatment) in a multiple crossover, double-blind study. Ketamine was administered by IV (n = 4), IM (n = 5) or SC (n = 6) injection. Dose titration commenced at 0.1 mg/kg, increasing by 0.1 mg/kg up to 0.5 mg/kg, given in separate treatment sessions separated by ≥1 week, with one placebo control treatment randomly inserted. Mood, psychotomimetic and hemodynamic effects were assessed and plasma ketamine concentrations assayed. RESULTS: Twelve participants achieved response and remission criteria, achieved at doses as low as 0.1 mg/kg. All three routes of administration resulted in comparable antidepressant effects. Fewest adverse effects were noted with the SC route. Antidepressant response, adverse effects and ketamine concentrations were dose-related. CONCLUSION: Antidepressant response occurred at a range of doses and at <0.5 mg/kg. The dose-titration approach is a practical method for optimizing the efficacy - side-effects trade-off on an individual patient basis. This pilot study provides preliminary evidence for SC injection as a practical, feasible and efficacious treatment approach.

Are the bipolar disorders best modelled categorically or dimensionally?

OBJECTIVE: Considerable debate exists as to whether the bipolar disorders are best classified according to a categorical or dimensional model. This study explored whether there is evidence for a single or multiple subpopulations and the degree to which differing diagnostic criteria correspond to bipolar subpopulations. METHOD: A mixture analysis was performed on 1081 clinically diagnosed (and a reduced sample of 497 DSM-IV diagnosed) bipolar I and II disorder patients, using scores on hypomanic severity (as measured by the Mood Swings Questionnaire). Mixture analyses were conducted using two differing diagnostic criteria and two DSM markers to ascertain the most differentiating and their associated clinical features. RESULTS: The two subpopulation solution was most supported although the entropy statistic indicated limited separation and there was no distinctive point of rarity. Quantification by the odds ratio statistic indicated that the clinical diagnosis (respecting DSM-IV criteria, but ignoring 'high' duration) was somewhat superior to DSM-IV diagnosis in allocating patients to the putative mixture analysis groups. The most differentiating correlate was the presence or absence of psychotic features. CONCLUSION: Findings favour the categorical distinction of bipolar I and II disorders and argue for the centrality of the presence or absence of psychotic features to subgroup differentiation.

Differentiating the bipolar disorders from borderline personality disorder.

OBJECTIVE: To identify features differentiating bipolar disorder (BP) from borderline personality disorder (BPD) and with each condition variably defined. METHOD: Participants were assigned a BP or BPD diagnosis on the basis of DSM criteria and, separately, by clinical judgment, and undertook a diagnostic interview and completed self-report measures. RESULTS: Predictors of BPD status varied according to diagnostic decisions, but with the most consistent items being childhood sexual abuse, childhood depersonalization, personality variables relating to relationship difficulties and sensitivity to criticism, and the absence of any BP family history. Across diagnostic groups, personality measure items alone predicted diagnostic allocation with an accuracy of 81-84%, the refined study variables other than hypo/manic features improved the classification rates to 88%, and when the presence or absence of hypo/manic features was added, classification rates increased to 92-95%. CONCLUSION: Study findings indicate that BPD can be differentiated from BP with a high degree of accuracy.