Perceptions and acceptability of Low Carbohydrate, High Fat (LCHF) diets among Māori whānau in Dunedin

OBJECTIVE: Low carbohydrate, high fat (LCHF) diets are currently much debated in both the media and the academic literature. However, little is known about the acceptability of these diets among Māori, who commonly consume diets high in carbohydrates, and how they might interpret recommendations to follow these diets. This study aims to investigate how LCHF diets are perceived by members of the Māori community (Dunedin) and some of the barriers and facilitators to following this type of diet. METHODS: Face-to-face interviews was conducted with n=18 Māori participants, (13 females, 5 males). They were recruited by word of mouth around the University of Otago and door approaches in low decile neighborhoods. Interviews focused on their perceptions about carbohydrates, such as how often they ate carbohydrates, and their food habits including high carbohydrate and high-fat foods. Other questions included the participants' thoughts on the LCHF diet, and if they would be willing to try an LCHF diet. Interview transcripts were analysed by inductive thematic analysis. RESULTS: Māori are highly motivated to living healthy lives. Motivating factors include family, culture, achieving a desired body weight and fear of developing diet-related diseases experienced by other family members. Participants’ knowledge and views of dietary fat are diverse. Saturated fat is still considered by many as unhealthy however, saturated fat from natural (less processed) sources is perceived by a significant number of participants as being healthy. As a staple food in Māori diets, starchy carbohydrates appeal because they are cheap, satiating and convenient. LCHF diets are viewed positively because it emphasizes eating fewer processed foods, which are associated with poor health outcomes and resembles diets of pre – colonised Māori. Barriers to LCHF diets were the cost of foods, concern for children’s food preference, lack of time, information, understanding and meal ideas. CONCLUSION: Our study suggests that perceptions of the LCHF diet by Māori adults is divided and their understanding is not based on sound evidence. Significant barriers and facilitators cause indecision in the application of the LCHF diet. Further research is needed to determine whether Māori perception of LCHF is accurate. KEYWORDS: Carbohydrates, High Fat, Diet, Nutrition, Processed foods, Saturated fat, Māori, Health, Traditional food

Coherent storage and phase modulation of single hard x-ray photons using nuclear excitons

Coherent storage and phase modulation of x-ray single-photon wave packets in resonant scattering of light off nuclei is investigated theoretically. We show that by switching off and on again the magnetic field in the nuclear sample, phase-sensitive storage of photons in the keV regime can be achieved. Corresponding $\pi$ phase modulation of the stored photon can be accomplished if the retrieving magnetic field is rotated by $180^{\circ}$. The development of such x-ray single-photon control techniques is a first step towards forwarding quantum optics and quantum information to shorter wavelengths and more compact photonic devices.Comment: 12 pages, 6 figures; v2 modified to match the published version, condensed to 4 figures, results unchange

Nuclear coherent population transfer with x-ray laser pulses

Coherent population transfer between nuclear states using x-ray laser pulses is studied. The laser pulses drive two nuclear transitions between three nuclear states in a setup reminding of stimulated Raman adiabatic passage used for atomic coherent population transfer. To compensate for the lack of $\gamma$-ray laser sources, we envisage accelerated nuclei interacting with two copropagating or crossed x-ray laser pulses. The parameter regime for nuclear coherent population transfer using fully coherent light generated by future X-Ray Free-Electron Laser facilities and moderate or strong acceleration of nuclei is determined. We find that the most promising case requires laser intensities of $10^{17}$-$10^{19}$ W/cm$^{2}$ for complete nuclear population transfer. As relevant application, the controlled pumping or release of energy stored in long-lived nuclear states is discussed.Comment: extended argument about experimental feasibility, added references, results unchanged; v3 updated to the published versio

TREX exposes the RNA binding domain of Nxf1 to enable mRNA export

The metazoan TREX complex is recruited to mRNA during nuclear RNA processing and functions in exporting mRNA to the cytoplasm. Nxf1 is an mRNA export receptor, which binds processed mRNA and transports it through the nuclear pore complex. At present, the relationship between TREX and Nxf1 is not understood. Here we show that Nxf1 uses an intramolecular interaction to inhibit its own RNA binding activity. When the TREX subunits Aly and Thoc5 make contact with Nxf1, Nxf1 is driven into an open conformation, exposing its RNA binding domain, allowing RNA binding. Moreover, the combined knockdown of Aly and Thoc5 drastically reduces the amount of Nxf1 bound to mRNA in vivo and also causes a severe mRNA export block. Together, our data indicate that TREX provides a license for mRNA export by driving Nxf1 into a conformation capable of binding mRNA

The Saccharomyces cerevisiae CWH8 gene is required for full levels of dolichol-linked oligosaccharides in the endoplasmic reticulum and for efficient N-glycosylation

The Saccharomyces cerevisiae mutant cwh8 was previously found to have an anomalous cell wall. Here we show that the cwh8 mutant has an N-glycosylation defect. We found that cwh8 cells were resistant to vanadate and sensitive to hygromycin B, and produced glycoforms of invertase and carboxypeptidase Y with a reduced number of N-chains. We have cloned the CWH8 gene. We found that it was nonessential and encoded a putative transmembrane protein of 239 amino acids. Comparison of the in vitro oligosaccharyl transferase activities of membrane preparations from wild type or cwh8Δ cells revealed no differences in enzyme kinetic properties indicating that the oligosaccharyl transferase complex of mutant cells was not affected. cwh8Δ cells also produced normal dolichols and dolichol-linked oligosaccharide intermediates including the full-length form Glc3Man9GlcNAc2. The level of dolichol-linked oligosaccharides in cwh8Δ cells was, however, reduced to about 20% of the wild type. We propose that inefficient N-glycosylation of secretory proteins in cwh8Δ cells is caused by an insufficient supply of dolichol-linked oligosaccharide substrat

The value of genetic testing in the diagnosis and risk stratification of arrhythmogenic right ventricular cardiomyopathy

BACKGROUND: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is characterized by risk of malignant ventricular arrhythmias (VA). ARVC is diagnosed using an array of clinical tests in the consensus-based task force criteria (TFC), one of which is genetic testing. OBJECTIVE: To investigate the value of genetic testing in diagnosing ARVC and its relation to the occurrence of first malignant VA. METHODS: A multicenter cohort of ARVC patients was scored using the revised 2010 TFC with and without genetic criterion, analyzing any resulting loss or delay of diagnosis. Malignant VA was defined as sustained ventricular arrhythmia (≥30s duration at ≥100 bpm or requiring intervention). RESULTS: We included 402 subjects (55% male, 54% proband, 40 [27-51] years old at presentation) who were diagnosed with definite ARVC. A total of 232 (58%) subjects fulfilled genetic testing criteria. Removing the genetic criterion caused loss of diagnosis in 18 (4%) patients (11/216 [5%] probands, 7/186 [4%] relatives), and delay of diagnosis ≥30 days in 22 (5%) patients (21/216 [10%] probands, 1/186 [0.5%] relative). A first malignant VA occurred in no patients who lost diagnosis and in 3 patients (3/216 [1%] probands and no relatives) during their diagnosis delay, none fatal. Time to event analysis showed no significant difference in time from diagnosis to malignant VA between pathogenic variant carriers and non-carriers. CONCLUSION: Disregarding the genetic criterion of the TFC caused loss or delay of diagnosis in 10% (n=40/402) of ARVC patients. Malignant VA occurred in 1% (n=3/402) of cases with lost or delayed diagnosis, none fatal

An evaluation of physical and augmented patient-specific intracranial aneurysm simulators on microsurgical clipping performance and skills: a randomized controlled study

Objective: In the era of flow diversion, there is an increasing demand to train neurosurgeons outside the operating room in safely performing clipping of unruptured intracranial aneurysms. This study introduces a clip training simulation platform for residents and aspiring cerebrovascular neurosurgeons, with the aim to visualize peri-aneurysm anatomy and train virtual clipping applications on the matching physical aneurysm cases. Methods: Novel, cost-efficient techniques allow the fabrication of realistic aneurysm phantom models and the additional integration of holographic augmented reality (AR) simulations. Specialists preselected suitable and unsuitable clips for each of the 5 patient-specific models, which were then used in a standardized protocol involving 9 resident participants. Participants underwent four sessions of clip applications on the models, receiving no interim training (control), a video review session (video), or a video review session and holographic clip simulation training (video + AR) between sessions 2 and 3. The study evaluated objective microsurgical skills, which included clip selection, number of clip applications, active simulation time, wrist tremor analysis during simulations, and occlusion efficacy. Aneurysm occlusions of the reference sessions were assessed by indocyanine green videoangiography, as well as conventional and photon-counting CT scans. Results: A total of 180 clipping procedures were performed without technical complications. The measurements of the active simulation times showed a 39% improvement for all participants. A median of 2 clip application attempts per case was required during the final session, with significant improvement observed in experienced residents (postgraduate year 5 or 6). Wrist tremor improved by 29% overall. The objectively assessed aneurysm occlusion rate (Raymond-Roy class 1) improved from 76% to 80% overall, even reaching 93% in the extensively trained cohort (video + AR) (p = 0.046). Conclusions: The authors introduce a newly developed simulator training platform combining physical and holographic aneurysm clipping simulators. The development of exchangeable, aneurysm-comprising housings allows objective radio-anatomical evaluation through conventional and photon-counting CT scans. Measurable performance metrics serve to objectively document improvements in microsurgical skills and surgical confidence. Moreover, the different training levels enable a training program tailored to the cerebrovascular trainees' levels of experience and needs