Mechanisms of imbalanced frontostriatal functional connectivity in obsessive-compulsive disorder.

The diagnosis of obsessive-compulsive disorder (OCD) has been linked with changes in frontostriatal resting-state connectivity. However, replication of prior findings is lacking, and the mechanistic understanding of these effects is incomplete. To confirm and advance knowledge on changes in frontostriatal functional connectivity in OCD, participants with OCD and matched healthy controls underwent resting-state functional, structural and diffusion neuroimaging. Functional connectivity changes in frontostriatal systems were here replicated in individuals with OCD (n = 52) compared with controls (n = 45). OCD participants showed greater functional connectivity (t = 4.3, PFWE = 0.01) between the nucleus accumbens (NAcc) and the orbitofrontal cortex (OFC) but lower functional connectivity between the dorsal putamen and lateral prefrontal cortex (t = 3.8, PFWE = 0.04) relative to controls. Computational modelling suggests that NAcc-OFC connectivity changes reflect an increased influence of NAcc over OFC activity and reduced OFC influence over NAcc activity (posterior probability, Pp > 0.66). Conversely, dorsal putamen showed reduced modulation over lateral prefrontal cortex activity (Pp > 0.90). These functional deregulations emerged on top of a generally intact anatomical substrate. We provide out-of-sample replication of opposite changes in ventro-anterior and dorso-posterior frontostriatal connectivity in OCD and advance the understanding of the neural underpinnings of these functional perturbations. These findings inform the development of targeted therapies normalizing frontostriatal dynamics in OCD.

Revisiting deficits in threat and safety appraisal in obsessive-compulsive disorder.

Current behavioural treatment of obsessive-compulsive disorder (OCD) is informed by fear conditioning and involves iteratively re-evaluating previously threatening stimuli as safe. However, there is limited research investigating the neurobiological response to conditioning and reversal of threatening stimuli in individuals with OCD. A clinical sample of individuals with OCD (N = 45) and matched healthy controls (N = 45) underwent functional magnetic resonance imaging. While in the scanner, participants completed a well-validated fear reversal task and a resting-state scan. We found no evidence for group differences in task-evoked brain activation or functional connectivity in OCD. Multivariate analyses encompassing all participants in the clinical and control groups suggested that subjective appraisal of threatening and safe stimuli were associated with a larger difference in brain activity than the contribution of OCD symptoms. In particular, we observed a brain-behaviour continuum whereby heightened affective appraisal was related to increased bilateral insula activation during the task (r = 0.39, pFWE = .001). These findings suggest that changes in conditioned threat-related processes may not be a core neurobiological feature of OCD and encourage further research on the role of subjective experience in fear conditioning.

Macronutrient content of donor milk from a regional human milk bank: variation with donor mother-infant characteristics.

Better understanding of the variation in macronutrient content of human donor milk (HDM) potentiates targeted nutrition for preterm babies. The present study describes the relationship of maternal age, parity, monthly lactation stage estimate (LSEm), daily volume of milk expressed (Vd), sex, gestation and birth weight z scores with macronutrient content of HDM. Multilevel mother-infant pair ID random intercept models were performed using the predictor variables above on the outcome HDM macronutrient content determined using mid-IR spectroscopy. Mean macronutrient content was also compared by gestational age and small for gestational age (SGA) (z score < -1·28) or appropriate for gestational age (AGA) (z score ≥ -1·28) categories. A total of 2966 samples of donations from 1175 mother-infant pairs to the UK Northwest Human Milk Bank between 2011 and 2017 were analysed. Mean protein, fat, carbohydrate and calculated energy were 0·89 (SD 0·24) g/dl, 2·99 (SD 0·96) g/dl, 7·09 (SD 0·44) g/dl, and 60·37 (SD 8·41) kcal/dl (252·59 (SD 35·19) kJ/dl), respectively. Preterm SGA HDM was significantly higher in protein, fat and energy content than term AGA HDM and significantly lower in carbohydrate content than term AGA HDM after controlling for LSEm, Vd and between-subject effects. Degree of prematurity did not influence macronutrient content. Between-subject effects accounted for more of the variance in macronutrient content than the fixed effects in the model. Despite this, SGA status, as well as prematurity, may be an important determinant of macronutrient content in human milk. As bioavailability of macronutrients from HDM is uncertain, studies evaluating growth and body composition in preterm and SGA babies fed HDM are warranted.

Non-disclosure of HIV status in UK sexual health clinics--a pilot study to identify non-disclosure within a national unlinked anonymous seroprevalence survey.

OBJECTIVES: To identify if HIV-infected individuals attending genitourinary clinics in the UK are not disclosing their HIV status, and to examine the potential utility of drug detection as a method to indicate non-disclosure. METHODS: HIV-positive samples from the unlinked anonymous seroprevalence survey from one London centre in 2009 had viral load (VL) assays performed to identify samples with VL below the level of detection (50 copies/ml, VLBLD) or <1000 copies/ml. After data matching, known HIV positives were excluded and the remaining samples analysed for the presence of a panel of antiretroviral drugs. RESULTS: Of 130 HIV-positive samples with sufficient clinical information and not undergoing an HIV test, 18 were classified as remaining undiagnosed after the clinic visit. Thirteen (72%, 95% CI: 47% to 90%) had a VLBLD (n=11) or VL <1000 copies/ml (n=2). Eight had sufficient volume to undergo ARV testing, and all were positive for the presence of drug; all with therapeutic levels of clinically appropriate combinations. CONCLUSIONS: Non-disclosure of HIV status occurs among individuals attending sexual health services in the UK. This study demonstrates the feasibility and utility of using both VL and ARV assays in serum samples. Furthermore, the close correlation of detection of ARV with VLBLD suggests drug detection would be a useful tool to monitor non-disclosure prospectively, thus enabling the use of stored serum samples in future studies. The extent to which these findings can be extrapolated to other settings, and the potential impact of non-disclosure on undiagnosed estimates warrants urgent prospective study.

Triose-phosphate isomerase deficiency is associated with a dysregulation of synaptic vesicle recycling in Drosophila melanogaster.

Introduction: Numerous neurodegenerative diseases are associated with neuronal dysfunction caused by increased redox stress, often linked to aberrant production of redox-active molecules such as nitric oxide (NO) or oxygen free radicals. One such protein affected by redox-mediated changes is the glycolytic enzyme triose-phosphate isomerase (TPI), which has been shown to undergo 3-nitrotyrosination (a NO-mediated post-translational modification) rendering it inactive. The resulting neuronal changes caused by this modification are not well understood. However, associated glycation-induced cytotoxicity has been reported, thus potentially causing neuronal and synaptic dysfunction via compromising synaptic vesicle recycling. Methods: This work uses Drosophila melanogaster to identify the impacts of altered TPI activity on neuronal physiology, linking aberrant TPI function and redox stress to neuronal defects. We used Drosophila mutants expressing a missense allele of the TPI protein, M81T, identified in a previous screen and resulting in an inactive mutant of the TPI protein (TPIM81T , wstd1). We assessed synaptic physiology at the glutamatergic Drosophila neuromuscular junction (NMJ), synapse morphology and behavioural phenotypes, as well as impacts on longevity. Results: Electrophysiological recordings of evoked and spontaneous excitatory junctional currents, alongside high frequency train stimulations and recovery protocols, were applied to investigate synaptic depletion and subsequent recovery. Single synaptic currents were unaltered in the presence of the wstd1 mutation, but frequencies of spontaneous events were reduced. Wstd1 larvae also showed enhanced vesicle depletion rates at higher frequency stimulation, and subsequent recovery times for evoked synaptic responses were prolonged. A computational model showed that TPI mutant larvae exhibited a significant decline in activity-dependent vesicle recycling, which manifests itself as increased recovery times for the readily-releasable vesicle pool. Confocal images of NMJs showed no morphological or developmental differences between wild-type and wstd1 but TPI mutants exhibited learning impairments as assessed by olfactory associative learning assays. Discussion: Our data suggests that the wstd1 phenotype is partially due to altered vesicle dynamics, involving a reduced vesicle pool replenishment, and altered endo/exocytosis processes. This may result in learning and memory impairments and neuronal dysfunction potentially also presenting a contributing factor to other reported neuronal phenotypes.

Brain signatures of chronic gut inflammation.

Gut inflammation is thought to modify brain activity and behaviour via modulation of the gut-brain axis. However, how relapsing and remitting exposure to peripheral inflammation over the natural history of inflammatory bowel disease (IBD) contributes to altered brain dynamics is poorly understood. Here, we used electroencephalography (EEG) to characterise changes in spontaneous spatiotemporal brain states in Crohn's Disease (CD) (n = 40) and Ulcerative Colitis (UC) (n = 30), compared to healthy individuals (n = 28). We first provide evidence of a significantly perturbed and heterogeneous microbial profile in CD, consistent with previous work showing enduring and long-standing dysbiosis in clinical remission. Results from our brain state assessment show that CD and UC exhibit alterations in the temporal properties of states implicating default-mode network, parietal, and visual regions, reflecting a shift in the predominance from externally to internally-oriented attentional modes. We investigated these dynamics at a finer sub-network resolution, showing a CD-specific and highly selective enhancement of connectivity between the insula and medial prefrontal cortex (mPFC), regions implicated in cognitive-interoceptive appraisal mechanisms. Alongside overall higher anxiety scores in CD, we also provide preliminary support to suggest that the strength of chronic interoceptive hyper-signalling in the brain co-occurs with disease duration. Together, our results demonstrate that a long-standing diagnosis of CD is, in itself, a key factor in determining the risk of developing altered brain network signatures.

Trends in pregnancy outcomes in Malawian adolescents receiving antimalarial and hematinic supplements.

OBJECTIVE: To describe pregnancy outcomes of adolescent and adult primigravidae receiving antimalarials and hematinic supplementation and compare findings with a survey in this area a decade earlier. DESIGN: Cross-sectional surveys in intervention and control sites. SETTING: Community, antenatal and delivery facilities in Chikwawa, Malawi. A rural area with year round malaria transmission. METHODS: Data on antenatal attendance, uptake of intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp-SP), birthweight, malaria, anaemia, for 2,152 primigravidae. OUTCOME MEASURES: Place of delivery, anaemia, malaria, birthweight. RESULTS: Fewer adolescent than adult primigravidae received >or=2 IPTp-SP doses (66 vs. 77.2%, p < 0.001), although more attended for two or more antenatal visits (92.0 vs. 76.7%, p < 0.001). Only 24.1% of adolescent primigravidae attended for hospital delivery. Women resident in intervention sites receiving IPTp-SP community distribution were more likely to choose a community delivery (p < 0.01), and have higher uptake of IPTp-SP (p = 0.036) than women not resident in these villages. Postnatal malaria prevalence was low and did not differ by age or place of delivery. Postnatal anaemia and low birthweight prevalence were higher in adolescents with community deliveries. Maternal anaemia and low birthweight prevalence were lower amongst adolescents in this study compared to estimates from the same population a decade previously. CONCLUSIONS: Adolescents had higher anaemia risk, lower IPTp-SP uptake than adults and under a quarter had a hospital delivery. Pregnancy outcomes improved compared to the survey a decade earlier. Monitoring and surveillance is required to reinforce to policy makers the need to improve adolescent coverage for available interventions.

Audit of tetanus prevention knowledge and practices in accident and emergency departments in England.

OBJECTIVES: To assess the knowledge and current tetanus prevention practices of various staff members in accident and emergency (A&E) departments. DESIGN, SETTING AND PARTICIPANTS: A structured questionnaire containing 16 questions on tetanus guidance, anti-tetanus practice, vaccination preparations and information on the population served by the department was sent to medical and nursing staff in A&E departments across England. RESULTS: 366 completed questionnaires from 67 hospitals were returned. 48.9% of the questionnaires were completed by the medical staff and 39.9% by the nursing staff at various grades. 75% of respondents said that their department had a local tetanus guideline, but only 29% stated that the tetanus guidelines were always followed. 31.4% of respondents said that injecting drug users were managed as a high-risk group in their department. Many respondents did not follow the national policy; they tended to err on the side of caution when it came to defining and treating tetanus-prone wounds, with 22.1% stating that they would consider any wound tetanus prone. Contrary to current Department of Health guidelines, 46.2% of respondents said that they would give a booster dose if the fifth dose had been given >10 years ago. CONCLUSIONS: There are clear differences between the recommended guidelines for tetanus prevention and current practice in A&E departments. The changes announced in 2002 do not seem to have been widely implemented. As a result, the apparent success of the national tetanus vaccination programme may be the result of more cautious clinical practice than would be expected from the UK policy. If national recommendations for tetanus are implemented in clinical practice, then the impact on control of the disease should be monitored closely.

Effect of nondisclosure of HIV status in sexual health clinics on unlinked anonymous HIV prevalence estimates in England, 2005-2009.

OBJECTIVES: To assess the extent of nondisclosure of known HIV status among sexual health clinic attendees and to quantify the impact of nondisclosure on estimates of undiagnosed HIV prevalence and of the proportion of patients remaining undiagnosed on leaving the clinic. METHODS: Serum samples from the unlinked anonymous survey of clinic attendees' archive were tested for antiretrovirals. Estimates of undiagnosed HIV were adjusted using the findings. RESULTS: Antiretrovirals were detected in 27% of samples taken from 'previously undiagnosed' attendees, who did not have an HIV test but were HIV positive as detected by unlinked anonymous testing, indicating nondisclosure; 24% of such samples from MSM had antiretrovirals present compared with 32% of heterosexual men and women. Antiretrovirals were detected in 33% of samples from London clinics and in 21% from non-London clinics. Following adjustment, the estimated prevalence of undiagnosed HIV decreased nonsignificantly from 3.04% (95% confidence interval 2.71-3.41) to 2.66% (2.35-3.01) among men who have sex with men (MSM), 0.31% (0.26-0.37) to 0.30% (0.25-0.36) in heterosexual men and 0.40% (0.35-0.46) to 0.37% (0.32-0.43) in women; 7% of MSM who do not have an HIV test at a clinic visit will be infected with HIV and remain unaware of their infection. CONCLUSION: Nondisclosure of HIV status to healthcare professionals occurs among clinic attendees. Adjustment for nondisclosure results in a small, nonsignificant decrease in the prevalence of undiagnosed HIV estimated from the unlinked anonymous survey in sexual health clinics. Testing the population of MSM not having an HIV test remains a priority as levels of undiagnosed HIV are high.

Vaccine effectiveness estimates, 2004-2005 mumps outbreak, England.

The United Kingdom and United States have recently experienced large outbreaks of mumps, which raises concerns about vaccine effectiveness. The effectiveness of the mumps component of the measles, mumps, rubella (MMR) vaccine was estimated using the screening method. In England from January 2004 through March 2005, 312 cases of mumps were reported in children eligible to have received 2 doses of MMR vaccine. Of these children, 52 (16.7%) had received 1 dose of MMR vaccine, and 97 (31.1%) had received 2 doses. Vaccine effectiveness was 88% (95% confidence interval [CI] 83%-91%) for 1 dose and 95% (95% CI 93%-96%) for 2 doses. The effectiveness of 1 dose declined from 96% (95% CI 81%-99%) in 2-year-olds to 66% (95% CI 30%-83%) in 11- to 12-year-olds, and the effectiveness of 2 doses declined from 99% (95% CI 97%-99.5%) in 5- to 6-year-olds to 86% (95% CI 74%-93%) in 11- to 12-year-olds (p<0.001 for 1 or 2 doses). Waning immunity may contribute to mumps outbreaks in older vaccinated populations.