Evidence for Elizabethkingia anophelis Transmission from Mother to Infant,Hong Kong

Elizabethkingia anophelis, recently discovered from mosquito gut, is an emerging bacterium associated with neonatal meningitis and nosocomial outbreaks. However, its transmission route remains unknown. We use rapid genome sequencing to investigate 3 cases of E. anophelis sepsis involving 2 neonates who had meningitis and 1 neonate’s mother who had chorioamnionitis. Comparative genomics revealed evidence for perinatal vertical transmission from a mother to her neonate; the 2 isolates from these patients, HKU37 and HKU38, shared essentially identical genome sequences. In contrast, the strain from another neonate (HKU36) was genetically divergent, showing only 78.6% genome sequence identity to HKU37 and HKU38, thus excluding a clonal outbreak. Comparison to genomes from mosquito strains revealed potential metabolic adaptations in E. anophelis under different environments. Maternal infection, not mosquitoes, is most likely the source of neonatal E. anophelis infections. Our findings highlight the power of genome sequencing in gaining rapid insights on transmission and pathogenesis of emerging pathogens.     

Microbiota That Affect Risk for Shigellosis in Children in Low-Income Countries

Pathogens in the gastrointestinal tract exist within a vast population of microbes. We examined associations between pathogens and composition of gut microbiota as they relate to Shigella spp./enteroinvasive Escherichia coli infection. We analyzed 3,035 stool specimens (1,735 nondiarrheal and 1,300 moderate-to-severe diarrheal) from the Global Enteric Multicenter Study for 9 enteropathogens. Diarrheal specimens had a higher number of enteropathogens (diarrheal mean 1.4, nondiarrheal mean 0.95; p<0.0001). Rotavirus showed a negative association with Shigella spp. in cases of diarrhea (odds ratio 0.31, 95% CI 0.17–0.55) and had a large combined effect on moderate-to-severe diarrhea (odds ratio 29, 95% CI 3.8–220). In 4 Lactobacillus taxa identified by 16S rRNA gene sequencing, the association between pathogen and disease was decreased, which is consistent with the possibility that Lactobacillus spp. are protective against Shigella spp.–induced diarrhea. Bacterial diversity of gut microbiota was associated with diarrhea status, not high levels of the Shigella spp. ipaH gene.     

Successes in sexual health communications development,programmatic implementation and evaluation in the Torres Strait region 2006 to 2012

Objective: To evaluate the Indigenous sexual health promotion program in the Torres Strait 2006–2012 that culminated in an education‐entertainment radio drama, Kasa Por Yarn (KPY). Methods: A mixed methods approach applied to unpublished program documents and program‐derived peer‐reviewed publications was utilised. Results: Early initiatives established a strong partnership with Torres Strait Islander stakeholders. Significant community engagement throughout ensured a positive process. Telephone survey data (n=100, TSI, 15–24 years) found: 95% had heard of KPY and 80% listened to 2 or more episodes (reach); 86% recalled storylines/characters (recall); and 54% talked about KPY to family/friends (resonance). There was improvement in sexual health knowledge scores (p<0.00) in the 15–19‐year‐old Torres Strait Islander population between 2007 and 2012. The 2012 15–24‐year‐old population exposed to KPY had higher sexual health knowledge scores compared with those unexposed (p=0.02). Conclusions: This is an uncommon comprehensive evaluation of population‐based sexual health communications strategies delivered over years in a remote Australian setting. The findings are encouraging but demonstrate that positive shifts take time and are incremental. Implications: In addition to clinical strategies, strategic and sustained investment in sexual health promotion expertise that leads community partnership and program development is required to reduce youth risk and prevent HIV/AIDS in remote populations.     

Psychiatric Morbidity in Ketamine Users Attending Counselling and Youth Outreach Services

Background: No study has examined ketamine users’ psychiatric morbidity using structured diagnostic instruments. The aim of this study was thus to determine the psychiatric comorbidity of community-based ketamine users using the Structured Clinical Interview for DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition), Axis I Disorders (SCID). Methods: A convenience sample of 200 frequent ketamine users was recruited from community organizations in Hong Kong. Participants were screened with the Severity of Dependence Scale (SDS), Beck Depression Inventory (BDI), Anxiety subscale of the Hospital Anxiety Depression Scale (HADSA), and SCID psychotic symptoms. Those who scored above the threshold (cutoff point of 8/9 on the BDI and 4/5 on HADSA) or displayed evidence of psychotic symptoms were referred for a structured clinical interview conducted by a psychiatrist. Results: One hundred and seventy participants scored above the cutoff point on 1 or more of the scales, and 115 participants attended the SCID interview. Fifty-one of these 115 participants received a psychiatric diagnosis of 1 or more comorbidities for the month preceding the interview. Mood disorders accounted for 80.4% of the diagnoses, anxiety disorders for 33.3%, and psychotic disorders for 7.8%. Conclusions: Female gender and history of psychiatric/psychological clinic attendance were significantly associated with comorbid psychiatric disorders, whereas ketamine dependence had a borderline association.     

Lower Monoamine Oxidase-A Total Distribution Volume in Impulsive and Violent Male Offenders with Antisocial Personality Disorder and High Psychopathic Traits: An [11C] Harmine Positron Emission Tomography Study

Antisocial personality disorder (ASPD) often presents with highly impulsive, violent behavior, and pathological changes in the orbitofrontal cortex (OFC) and ventral striatum (VS) are implicated. Several compelling reasons support a relationship between low monoamine oxidase-A (MAO-A), an enzyme that regulates neurotransmitters, and ASPD. These include MAO-A knockout models in rodents evidencing impulsive aggression and positron emission tomography (PET) studies of healthy subjects reporting associations between low brain MAO-A levels and greater impulsivity or aggression. However, a fundamental gap in the literature is that it is unknown whether brain MAO-A levels are low in more severe, clinical disorders of impulsivity, such as ASPD. To address this issue, we applied [¹¹C] harmine PET to measure MAO-A total distribution volume (MAO-A V_T), an index of MAO-A density, in 18 male ASPD participants and 18 age- and sex-matched controls. OFC and VS MAO-A V_T were lower in ASPD compared with controls (multivariate analysis of variance (MANOVA): F_2,33=6.8, P=0.003; OFC and VS MAO-A V_T each lower by 19%). Similar effects were observed in other brain regions: prefrontal cortex, anterior cingulate cortex, dorsal putamen, thalamus, hippocampus, and midbrain (MANOVA: F_7,28=2.7, P=0.029). In ASPD, VS MAO-A V_T was consistently negatively correlated with self-report and behavioral measures of impulsivity (r=−0.50 to −0.52, all P-values<0.05). This study is the first to demonstrate lower brain MAO-A levels in ASPD. Our results support an important extension of preclinical models of impulsive aggression into a human disorder marked by pathological aggression and impulsivity.     

Common and Dissociable Dysfunction of the Reward System in Bipolar and Unipolar Depression

Unipolar and bipolar depressive episodes have a similar clinical presentation that suggests common dysfunction of the brain’s reward system. Here, we evaluated the relationship of both dimensional depression severity and diagnostic category to reward system function in both bipolar and unipolar depression. In total, 89 adults were included, including 27 with bipolar depression, 25 with unipolar depression, and 37 healthy comparison subjects. Subjects completed both a monetary reward task and a resting-state acquisition during 3T BOLD fMRI. Across disorders, depression severity was significantly associated with reduced activation for wins compared with losses in bilateral ventral striatum, anterior cingulate cortex, posterior cingulate cortex, and right anterior insula. Resting-state connectivity within this reward network was also diminished in proportion to depression severity, most notably connectivity strength in the left ventral striatum. In addition, there were categorical differences between patient groups: resting-state connectivity at multiple reward network nodes was higher in bipolar than in unipolar depression. Reduced reward system task activation and resting-state connectivity therefore appear to be a brain phenotype that is dimensionally related to depression severity in both bipolar and unipolar depression. In contrast, categorical differences in reward system resting connectivity between unipolar and bipolar depression may reflect differential risk of mania. Reward system dysfunction thus represents a common brain mechanism with relevance that spans categories of psychiatric diagnosis.     

Region-selective permeability of the blood-brain barrier to α-aminoisobutyric acid during thiamine deficiency and following its reversal

Thiamine deficiency (TD) results in focal lesions in several regions of the rat brain including the thalamus and inferior colliculus. Since alterations in blood-brain barrier (BBB) integrity may play a role in this damage, we have examined the influence of TD on the unidirectional blood-to-brain transfer constant (K_i) of the low molecular weight species α-aminoisobutyric acid (AIB) in vulnerable and non-vulnerable brain regions at different stages during progression of the disorder, and following its reversal with thiamine. Analysis of the regional distribution of K_i values showed early (day 10) increased transfer of [¹⁴C]-AIB across the BBB in the vulnerable medial thalamus as well as the non-vulnerable caudate and hippocampus. At the acute symptomatic stage (day 14), more widespread BBB permeability changes were detected in most areas including the lateral thalamus, inferior colliculus, and non-vulnerable cerebellum and pons. Twenty-four hours following thiamine replenishment, a heterogeneous pattern of increased BBB permeability was observed in which many structures maintained increased uptake of [¹⁴C]-AIB. No increase in the [³H]-dextran space, a marker of intravascular volume, was detected in brain regions during the progress of TD, suggesting that BBB permeability to this large tracer was unaffected. These results indicate that BBB opening i) occurs early during TD, ii) is not restricted to vulnerable areas of the brain, iii) is progressive, iv) persists for at least 24 h following treatment with thiamine, and v) is likely selective in nature, depending on the molecular species being transported.