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Background: Ultra high-risk (UHR) criteria were introduced to identify people at imminent risk of developing psychosis. To improve prognostic accuracy, additional clinical and biological risk factors have been researched. Associations between psychotic disorders and infections with Toxoplasma gondii and Herpesviridae have been found. It is unknown if exposure to those pathogens increases the risk of transition to psychosis in UHR cohorts., Methods: We conducted a long-term follow-up of 96 people meeting UHR criteria, previously seen at the Personal Assessment and Crisis Evaluation (PACE) clinic, a specialized service in Melbourne, Australia. Transition to psychosis was assessed using the Comprehensive Assessment of the At-Risk Mental State (CAARMS) and state public mental health records. The relationship between IgG antibodies to Herpesviridae (HSV-1, HSV-2, CMV, EBV, VZV) and Toxoplasma gondii and risk for transition was examined with Cox regression models., Results: Mean follow-up duration was 6.46 (±3.65) years. Participants who transitioned to psychosis (n = 14) had significantly higher antibody titers for Toxoplasma gondii compared to those who did not develop psychosis (p = 0.03). After adjusting for age, gender and year of baseline assessment, seropositivity for Toxoplasma gondii was associated with a 3.6-fold increase in transition hazard in multivariate Cox regression models (HR = 3.6; p = 0.036). No significant association was found between serostatus for Herpesviridae and risk of transition., Conclusions: Exposure to Toxoplasma gondii may contribute to the manifestation of positive psychotic symptoms and increase the risk of transitioning to psychosis in UHR individuals., (Copyright © 2021. Published by Elsevier B.V.)

There has been limited research into the predictive value of basic symptoms and their relationship with other psychopathology in patients identified using the 'ultra high risk' (UHR) for psychosis approach. The current study investigated whether basic symptoms, specifically cognitive disturbances (COGDIS), were associated with a greater risk of transition to psychotic disorder and persistent attenuated psychotic symptoms (APS) at medium term follow-up (mean = 3.4 years) in UHR patients, as well as with general psychopathology at baseline. The sample included 304 UHR participants (mean age = 19.12 years) involved in an international multicenter trial of omega-3 fatty acids. UHR individuals who also met the COGDIS criteria (basic symptoms risk criteria) did not have a greater risk of transition than those who met the UHR criteria alone. However, meeting COGDIS risk criteria was associated with a greater likelihood of meeting the UHR attenuated psychotic symptoms risk group (i.e., having persistent attenuated psychotic symptoms) at 12-month follow-up (odds ratio = 1.85; 95% CI = 1.03, 3.32). Greater severity of cognitive basic symptoms was also independently associated with more severe general psychopathology at study entry. The findings do not support the notion that combined risk identification approaches (UHR and basic symptoms) aid in the identification of individuals at greatest risk of psychosis, although this interpretation is limited by the modest transition to psychosis rate (13%) and the time of follow up. However, the findings indicate that basic symptoms may be a clinically useful marker of more severe general psychopathology in UHR groups and risk for persistent attenuated psychotic symptoms., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Considerable research has been conducted seeking risk factors and constructing prediction models for transition to psychosis in individuals at ultra-high risk (UHR). Nearly all such research has only employed baseline predictors, i.e. data collected at the baseline time point, even though longitudinal data on relevant measures such as psychopathology have often been collected at various time points. Dynamic prediction, which is the updating of prediction at a post-baseline assessment using baseline and longitudinal data accumulated up to that assessment, has not been utilized in the UHR context. This study explored the use of dynamic prediction and determined if it could enhance the prediction of frank psychosis onset in UHR individuals. An emerging statistical methodology called joint modelling was used to implement the dynamic prediction. Data from the NEURAPRO study (n = 304 UHR individuals), an intervention study with transition to psychosis study as the primary outcome, were used to investigate dynamic predictors. Compared with the conventional approach of using only baseline predictors, dynamic prediction using joint modelling showed significantly better sensitivity, specificity and likelihood ratios. As dynamic prediction can provide an up-to-date prediction for each individual at each new assessment post entry, it can be a useful tool to help clinicians adjust their prognostic judgements based on the unfolding clinical symptomatology of the patients. This study has shown that a dynamic approach to psychosis prediction using joint modelling has the potential to aid clinicians in making decisions about the provision of timely and personalized treatment to patients concerned., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Individuals are considered Ultra-High-Risk (UHR) for psychosis if they meet a set of standardised criteria including presumed genetic vulnerability (Trait), or a recent history of Attenuated Psychotic Symptoms (APS) or Brief Limited Intermittent Psychotic Symptoms (BLIPS). Recent calls to revise these criteria have arisen from evidence that Trait, APS and BLIPS groups may transition to psychosis at different rates. Concurrently, it has become clear that the UHR status confers clinical risk beyond transition to psychosis. Specifically, most UHR individuals will not develop psychosis, but will experience high rates of non-psychotic disorders, persistent APS and poor long-term functional outcomes. Rather than focus on transition, the present study investigated whether UHR groups differ in their broader clinical risk profile by examining baseline clinical characteristics and long-term outcomes other than transition to psychosis. Four UHR groups were defined: Trait-only, APS-only, Trait+APS, and any BLIPS. Participants (N=702) were recruited upon entry to early intervention services and followed-up over a period of up to 13years (mean=4.53, SD=3.84). The groups evidenced similar symptom severity (SANS for negative symptoms, BPRS for positive and depression/anxiety symptoms) and psychosocial functioning (SOFAS, GAF, QLS) at baseline and follow-up as well as similar prevalence of non-psychotic disorders at follow-up. Our findings demonstrate that UHR groups evidence a similar clinical risk profile when we expand this beyond transition to psychosis, and consequently support maintaining the existing UHR criteria., (Copyright © 2017. Published by Elsevier B.V.)

Background: The rate of transition to psychotic disorder in ultra high risk (UHR) patients has declined in recent cohorts. The reasons for this are unclear, but may include a lead-time bias, earlier intervention, a change in clinical characteristics of cohorts, and treatment changes., Aims: In this paper we examined the two possibilities related to reduction in duration of symptoms prior to clinic entry, i.e., lead-time bias and earlier intervention., Method: The sample consisted of all UHR research participants seen at the PACE clinic, Melbourne between 1993 and 2006 (N=416), followed for a mean of 7.5years (the 'PACE 400' cohort). Duration of symptoms was analysed by four baseline year time periods. Analysis of transition rate by duration of symptoms was restricted to more homogenous sub-samples (pre-1998 and pre-2001) in order to minimize confounding effects of change in patient characteristics or treatments. These cohorts were divided into those with a short and long duration of symptoms using a cut-point approach., Results: Duration of symptoms prior to entry did not reduce significantly between 1993 and 2006 (p=0.10). The group with a short duration of symptoms showed lower transition rates and did not catch up in transition rate compared to the long duration of symptoms group., Discussion: These data suggest that, while earlier intervention or lead-time bias do not fully account for the declining transition rate in UHR cohorts, it appears that earlier intervention may have exerted a stronger influence on this decline than length of follow-up period (lead-time bias)., (Copyright © 2016 Elsevier B.V. All rights reserved.)

It is thought that hypothalamic-pituitary-adrenal (HPA) axis functioning mediates between the experience of stress and development of psychotic symptoms. This study aimed to evaluate this model in a cohort of young people at ultra high risk (UHR) of psychosis. Information about the experience of psychological symptoms and recent stressful experiences was obtained from 23 young people who met UHR criteria. Plasma samples were taken to assess cortisol and glucocorticoid receptor numbers, and an MRI scan was also performed. Plasma cortisol levels were significantly and positively correlated with the experience of 'hassles' but not with the experience of stressful life events. Significant positive associations were also found between plasma cortisol levels and level of depression and anxiety. No significant relationships were found between plasma cortisol level and global psychopathology, psychotic symptomatology, functioning or pituitary and hippocampal volumes. These results suggest that the number of hassles experienced by young people at UHR of psychosis could be an important factor in raising their cortisol levels, which might, in turn, affect the severity of depressive and anxiety symptoms. No other relationships were found between plasma cortisol levels and the experience of psychotic symptoms, functioning or hippocampal and pituitary volumes. These results indicate possible impairment in HPA-axis functioning in the early stages of psychotic illness, but further investigation of the relationships between these parameters is required.

Objective: We examined if age of onset of psychiatric symptoms and/or sex predict conversion to non-affective or affective psychosis in individuals considered to be at ultra-high risk for schizophrenia., Method: Participants (n=86) were offered treatment and monthly follow-up until transition to psychosis, or for 12 months if they did not meet exit criteria for psychotic disorder. Individuals without transition to psychosis at 12-month were reassessed approximately 3 years after the end of the treatment phase. Ultra-high risk was defined by the presence of subthreshold and/or self-limiting psychotic symptoms and/or having a family history of psychotic disorder combined with functional decline. Cox regressions after adjustment for treatment interventions were applied to investigate associations between age of onset, sex, and other baseline measures with progression to psychotic outcomes., Results: Early age of onset of psychiatric symptoms, in particular onset before age 18 was the only tested variable that significantly predicted non-affective psychosis. Independent significant predictors of affective psychosis were poor functioning, female sex and the presence of a combination of intake criteria (family history of psychosis plus drop in functioning, and attenuated and/or brief limited psychotic symptoms) at baseline., Conclusions: Age of onset of psychiatric symptoms is the single most important factor associated with conversion to non-affective psychosis in ultra-high risk individuals.

Background: Many epidemiological studies indicate suicide rates are higher for males than females and for urban than rural. Here we re-examine gender, urban and rural differentials in suicide in Australia and Beijing (China). More specifically, to test the two hypotheses (i) that the male to female ratio is larger than one; (ii) that the urban suicide rate is higher than the rural in both places., Methods: Suicide data with information of gender, rural and urban regions for Australia and Beijing (China) for the period of 1991-1996 were used. Ratios between the gender-specific urban and rural suicides rates with the associated confidence intervals were constructed to examine gender, urban and rural differentials in Australia and Beijing., Results: The rural suicide rate in Beijing for both genders was higher than for their urban counterparts. Further, the elderly had the highest suicide rate followed by women aged 20-29. Also, the male to female ratio in China was less than one. In Australia, the rural male suicide rate was higher than the urban whereas the urban female suicide rate was higher than the rural. The male to female ratio was 4 to 1. The differences in rural to urban and male to female ratios between Australia and Beijing are statistically significant., Conclusions: In contrast to the west, male suicide rates are not higher than female rates in China. Urban rates are not necessarily higher than rural rates --not even in a western setting. Cultural factors and regional differences in socio-economic situation are significant in explaining the low gender ratio and the relatively higher suicide rates in rural China., Limitations: The suicide rate in the Beijing region might not exactly reflect the same for the whole of China.

Objectives: To determine the optimal method for detecting ascending aortic atheroma intraoperatively by comparing manual palpation by the operating surgeon, intraoperative transesophageal echocardiography, and epiaortic ultrasound (linear and phased-array imaging); and to assess risk factors for severe aortic atheroma., Design: A longitudinal prospective study. Assessment of the atheroma by manual palpation was blinded to the results of the ultrasound images., Setting: The study was performed in a single university tertiary referral hospital., Participants: One hundred consecutive patients undergoing coronary bypass or valve surgery were studied after their written, informed consent., Interventions: Potential risk factors were evaluated by both a patient questionnaire and examination of prior hospital records. The ascending aorta was assessed by the following methods: manual palpation by the operating surgeon, intraoperative transesophageal echocardiography, and epiaortic ultrasound (linear and phased-array imaging) performed by an echocardiologist. For analysis, the ascending aorta was divided into three equal segments: proximal, mid, and distal, corresponding to regions of different operative manipulations., Measurements and Main Results: Age older than 70 years and hypertension were significant risk factors for severe ascending aortic atheroma with adjusted odds ratios of 3.3 (95% CI, 1.2 to 9.3) and 3.9 (95% CI, 1.3 to 12.0), respectively. There was no significant difference in atheroma detection between the two ultrasonic epiaortic probes in any segment; however, epiaortic probes were superior to manual palpation in all segments and also superior to transesophageal echocardiography in the mid and distal segments of the ascending aorta., Conclusions: Age older than 70 years and hypertension are significant risk factors for severe ascending aortic atheroma. Intraoperative detection of ascending aortic atheroma is best achieved by epiaortic ultrasound with either a linear or phased array transducer. Transesophageal echocardiography is an insensitive technique for evaluation of mid and distal ascending aortic atheroma and, therefore, of little value in guiding surgical manipulations such as cross-clamping.

A prospective breast feeding survey in a large obstetric hospital was carried out from 1988 to 1991. For each year, a sample of women were interviewed following delivery and data was collected which included the method of feeding, patient status (public or private patients), age, parity, (including previous breast feeding experience), marital status, country of birth and the number of babies. The mother's feeding method after delivery and on discharge from hospital were recorded. Women who were breast feeding on discharge were interviewed at 3 months. When putting the figures for the 4 years together, the breast feeding commencement rate was 88%, the breast feeding rate on discharge was 80% and the breast feeding rate at 3 months was between 51% and 57%. Factors found to be affecting the breast feeding rate at 3 months included patient status, age and parity. Problems experienced by the mothers after discharge from hospital included nipple pain, nipple trauma and mastitis. Private patients reported a significantly higher rate of mastitis than public patients.

A scheme for realizing a photon number amplifier by use of a high-quantum-efficiency photodetector and a number-state semiconductor laser is analyzed. It is found that the photon number amplifier is not significantly limited by the electronic amplifier noise or by the laser quantum efficiency for input states that are nearly classical.

Compared with the use of phase-insensitive linear quantum amplifiers of the same gain G, the use of phase-sensitive linear amplifiers on phase coherent classical light sources in an amplifier-attenuator chain reduces the total quantum noise power by a factor of 4, the homodyne noise variance by 2, and the photon number variance by 2-8 and suppresses the Kerr effect linear phase fluctuation variance as well as the soliton timing-error variance by 2G(2).

It is shown how the photon-number amplifier may be used to make, for either novel or conventional sources, an efficient direct-detection receiver and transceiver in a local-area network environment and how the parametric amplifier may be used similarly for a homodyne-detection receiver.

A review was conducted of 234 consecutive patients with hypertrophic pyloric stenosis (HPS) proven at operation. The relationship of age, sex, the duration of symptoms and the clinical degree of dehydration to the severity of metabolic derangement as reflected by alterations in serum electrolytes and acid-base status, was analysed statistically. The length of history and the degree of dehydration was found to have predictive value in identifying those likely to have major metabolic disturbances. Where severe vomiting has persisted for more than 1 week, major derangements of the biochemical parameters should be anticipated; and where clinical assessment of dehydration is estimated as being greater than 5%, there is almost always some major biochemical abnormality present. Nevertheless, variation in individual cases necessitates that all patients with suspected HPS should have serum electrolytes and acid-base estimations performed.

It is shown that degenerate four-wave mixing generates two-photon coherent states (TCS) of the radiation field for modes that are proper combinations of the output object and image waves. TCS light has novel quantum behavior, which can be probed by homodyne detection, intensity interferometry, or photocount statistics. Numerical estimates indicate that the generation and detection of TCS light via degenerate four-wave mixing and homodyne detection can be accomplished with current technology.