Probing the physiological role of the plastid outer-envelope membrane using the oemiR plasmid collection.

Plastids are the site of complex biochemical pathways, most prominently photosynthesis. The organelle evolved through endosymbiosis with a cyanobacterium, which is exemplified by the outer envelope membrane that harbors more than 40 proteins in Arabidopsis. Their evolutionary conservation indicates high significance for plant cell function. While a few proteins are well-studied as part of the protein translocon complex the majority of outer envelope protein functions is unclear. Gaining a deeper functional understanding has been complicated by the lack of observable loss-of-function mutant phenotypes, which is often rooted in functional genetic redundancy. Therefore, we designed outer envelope-specific artificial micro RNAs (oemiRs) capable of downregulating transcripts from several loci simultaneously. We successfully tested oemiR function by performing a proof-of-concept screen for pale and cold-sensitive mutants. An in-depth analysis of pale mutant alleles deficient in the translocon component TOC75 using proteomics provided new insights into putative compensatory import pathways. The cold stress screen not only recapitulated 3 previously known phenotypes of cold-sensitive mutants but also identified 4 mutants of additional oemiR outer envelope loci. Altogether our study revealed a role of the outer envelope to tolerate cold conditions and showcasts the power of the oemiR collection to research the significance of outer envelope proteins.

Low awareness of high sodium intake among older Chinese people.

Awareness is one of the first steps in a lifestyle modification process. Since older adults are at a higher risk of hypertension, maintaining low sodium intake is of utmost importance. Yet, it is uncertain if older adults have an awareness of their sodium intake. This study aimed to explore self-perceived sodium intake among older Chinese people and compare it with various measures of sodium intake. A cross-sectional study was conducted in Hong Kong in 2015. Data were collected from 24-h urinary sodium excretion (UNa24) measurements, dietary sodium intake by 24-h diet recalls and self-perceived salt intake levels among the older Hong Kong population. Kappa statistics and a paired t-test were used to compare the different measures. Fifty-nine participants provided complete 24-h urine samples. The mean (±SD) UNa24 of participants was 2846 ± 1253 mg, of which 74.6% exceeded the recommended daily sodium intake. About 87.8% of participants with UNa24 values >2000 mg perceived their sodium intake as too little or just right. The kappa statistic between UNa24 and self-perception was insignificantly different from zero (κ = -0.003, p-value = 0.909). The UNa24 estimates were significantly higher than those estimated from the 24-h diet recalls by 1203 mg (p-value <0.001). The findings imply that the low awareness of excessive sodium intake should be raised among older people to promote a healthy intake of sodium.

Low level of knowledge of heart attack symptoms and inappropriate anticipated treatment-seeking behaviour among older Chinese: a cross-sectional survey.

BACKGROUND: Prehospital delay of acute myocardial infarction (AMI) is common globally, and Hong Kong-home of a rapidly ageing Chinese population-is not an exception. Seeking emergency medical care promptly is important for patients. Treatment-seeking behaviours have been shown to be associated with knowledge of AMI symptoms and specific cultural beliefs. This study aimed to assess the level of knowledge of AMI symptoms and expected treatment-seeking behaviour among older Chinese in Hong Kong. METHODS: A cross-sectional population-based survey was conducted at the Elderly Health Centres in Hong Kong from March to September 2016. Face-to-face interviews were conducted with a structured questionnaire based on previous studies and local adaptations. RESULTS: Among 1804 people aged 65 years and above who completed the questionnaire, chest pain (80.2%), palpitations (75.8%) and fainting (71.9%) were the major symptoms recognised as AMI related. Meanwhile, stomach ache (46.9%), coughing (45.4%) and neck pain (40.8%) were recognised as not AMI related. The mean expected discomfort intensity during AMI onset was 7.7 out of 10 (SD=2.1). Regarding the expected treatment-seeking behaviour, seeking non-emergent medical care was the most popular action when AMI symptoms emerged during the day, without chest pain or with lower discomfort intensity, whereas calling an ambulance was the most common option when AMI symptoms emerged at night or with high discomfort intensity. CONCLUSIONS: To minimise delays in seeking treatment, future health education should focus on increasing the public knowledge of AMI symptoms and the need to call an ambulance during an emergency.