Mitophagy antagonism by ZIKV reveals Ajuba as a regulator of PINK1 signaling, PKR-dependent inflammation, and viral invasion of tissues

Dysregulated inflammation dominated by chemokine expression is a key feature of disease following infection with the globally important human pathogens Zika virus (ZIKV) and dengue virus, but a mechanistic understanding of how pro-inflammatory responses are initiated is lacking. Mitophagy is a quality-control mechanism that regulates innate immune signaling and cytokine production through selective degradation of damaged mitochondria. Here, we demonstrate that ZIKV nonstructural protein 5 (NS5) antagonizes mitophagy by binding to the host protein Ajuba and preventing its translocation to depolarized mitochondria where it is required for PINK1 activation and downstream signaling. Consequent mitophagy suppression amplifies the production of pro-inflammatory chemokines through protein kinase R (PKR) sensing of mitochondrial RNA. In Ajuba^-/- mice, ZIKV induces early expression of pro-inflammatory chemokines associated with significantly enhanced dissemination to tissues. This work identifies Ajuba as a critical regulator of mitophagy and demonstrates a role for mitophagy in limiting systemic inflammation following infection by globally important human viruses.

Preliminary exploration of the use of the Children's Eating Behaviour Questionnaire (CEBQ) and Feeding Practices and Structure Questionnaire (FPSQ) in Vietnamese mothers

OBJECTIVE

This preliminary pilot study aims to explore the use of the Feeding Practices and Structure Questionnaire (FPSQ) and Children's Eating Behaviour Question (CEBQ) in a sample of Vietnamese mothers.

SUBJECTS/METHODS

Cross-sectional data from the FPSQ and CEBQ were collected from a convenience sample of mothers (n = 102) who attended the Ho Chi Minh City Nutrition Centre in Viet Nam. Mothers had at least one child aged 2-5 years. The reliability of the questionnaire subscales was tested using Cronbach's alpha coefficients. Face validity was assessed using dialogue from a translation-back-translation procedure undertaken by an expert committee, and cognitive interviews conducted in a subsample of mothers (n = 6). Based on these findings, exploratory factor analyses (EFAs) were performed to assess the underlying structures of both questionnaires in this sample.

RESULTS

Cronbach's alpha coefficients for the original questionnaires ranged from 0.23 to 0.92. Limitations in translation and comprehension of items surfaced, warranting modifications of the questionnaires, which were subsequently examined using EFA. EFA of the FPSQ and CEBQ revealed a six-factor structure with 23 items, and a six-factor structure with 27 items, respectively, which were interpretable solutions for this sample. Cronbach's alpha coefficients were >0.70 for all subscales in the revised questionnaires.

CONCLUSIONS

Modified versions of the FPSQ and CEBQ are proposed for use in Viet Nam. However, prior to their use, further reliability and validity testing must be undertaken in larger samples, including assessment of test-retest reliability and construct validity, as well as confirmatory factor analysis to verify the proposed factor structures.

Exploring approaches to dietetic assessment of a common task across different universities through assessment moderation

BACKGROUND

Assessment presents one of the greatest challenges to evaluating health professional trainee performance, as a result of the subjectivity of judgements and variability in assessor standards. The present study aimed to test a moderation procedure for assessment across four independent universities and explore approaches to assessment and the factors that influence assessment decisions.

METHODS

Assessment tasks designed independently by each of the four universities to assess student readiness for placement were chosen for the present study. Each university provided four student performance recordings for moderation. Eight different academic assessors viewed the student performances and assessed them using the corresponding university assessment instrument. Assessment results were collated and presented back to the assessors, together with the original university assessment results. Results were discussed with assessors to explore variations. The discussion was recorded, transcribed, thematically analysed and presented back to all assessors to achieve consensus on the emerging major learnings.

RESULTS

Although there were differences in absolute scores, there was consistency (12 out of 16 performances) in overall judgement decisions regarding placement readiness. Proficient communication skills were considered a key factor when determining placement readiness. The discussion revealed: (i) assessment instruments; (ii) assessor factors; and (iii) the subjectivity of judgement as the major factors influencing assessment.

CONCLUSIONS

Assessment moderation is a useful method for improving the quality of assessment decisions by sharing understanding and aligning standards of performance.

Exploring power and influence in nutrition policy in Australia

The food industry is often described as having more power and influence in nutrition policymaking than nutrition professionals, scientists and other practitioners working for the public interest; yet authors often allude to this point as an assumed truth, rather than an evidence-based fact. This paper applies social network analysis techniques to provide a concise evidence-based demonstration of the food industry's capacity to influence nutrition policymaking networks in Australia. Network analysis using four rounds of data collection was undertaken, and the capacity of individual actors and occupational categories to influence policy decision makers were analysed. Network graphs were developed using cluster analysis to identify the structure of clusters and the path distance of actors from decision makers. The assumed advantage for the 'food industry' was present both strategically in overall network position and with respect to the number of direct access points to 'decision makers', whereas 'nutrition professionals' were densely clustered together with limited links to key 'decision makers'. The results demonstrate that the food industry holds the strategic high ground in advocating their interests to policymakers in the contexts studied. Nutrition professionals may be hampered by their reliance on strong ties with other nutrition professionals as well as limited direct links to 'decision makers'.

Many respiratory viruses have temporal association with meningococcal disease

BACKGROUND

Previous ecological studies have shown a temporal and spatial association between influenza epidemics and meningococcal disease (MNG); however, none have examined more than two respiratory viruses.

METHODS

Data were obtained in Chile between 2000 and 2005 on confirmed cases of MNG and all confirmed cases of respiratory viruses (influenza A and B; parainfluenza; adenovirus; and respiratory syncytial virus [RSV]). Both variables were divided by epidemiological weeks, age range, and regions. Models of transference functions were run for rates of MNG.

RESULTS

In this period, 1022 reported cases of MNG and 34,737 cases of respiratory virus were identified (25,137 RSV; 4300 parainfluenza; 2527 influenza-A; 356 influenza-B; and 2417 adenovirus). RSV was the major independent virus temporally associated to MNG (it appears one week before MNG), followed by parainfluenza, influenza-B, adenovirus, and influenza-A.

CONCLUSIONS

The rate of MNG in Chile is temporally associated to all of the respiratory viruses studied, but with variability according age range, and regions.

[Pituitary stalk transection syndrome]

BACKGROUND

Pituitary stalk transection is a non-negligible cause of growth hormone (GH) deficiency.

POPULATION AND METHODS

We studied 22 children (13 boys, nine girls) aged at the first clinical manifestations from 2 days to 10 years (average = 5.33 +/- 2 years). Pituitary stalk transection was assessed by the means of magnetic resonance imaging (MRI). The children's past history showed fetal distress in 12 cases (54.5%), cranial trauma in three (13%) and a midline anomaly in three (13%). The first clinical manifestations were neonatal hypoglycemia (two cases), decreased growth velocity (18 cases) and diabetes insipidus (two cases).

RESULTS

GH deficiency was complete, present from the onset in 19 of 22 cases and isolated in four. Fifteen of 22 cases had adreno-corticotrophic hormone (ACTH) and thyroid stimulating hormone (TSH) deficiency. Diabetes insipidus was present in six cases and revealed the syndrome in two. All children older than normal age of puberty (n = 10) had gonadotropin deficiency. In our study, these hormonal anomalies progressed from isolated GH deficiency to multiple hormonal deficiencies.

CONCLUSION

The recently described stalk transection syndrome is relatively frequent and should be suspected after cranial trauma or fetal distress syndrome. The outcome is progressive evolution towards panhypopituitarism and these patients require regular clinical survey and hormonal controls.