DGAT1 activity synchronises with mitophagy to protect cells from metabolic rewiring by iron depletion.

Mitophagy removes defective mitochondria via lysosomal elimination. Increased mitophagy coincides with metabolic reprogramming, yet it remains unknown whether mitophagy is a cause or consequence of such state changes. The signalling pathways that integrate with mitophagy to sustain cell and tissue integrity also remain poorly defined. We performed temporal metabolomics on mammalian cells treated with deferiprone, a therapeutic iron chelator that stimulates PINK1/PARKIN-independent mitophagy. Iron depletion profoundly rewired the metabolome, hallmarked by remodelling of lipid metabolism within minutes of treatment. DGAT1-dependent lipid droplet biosynthesis occurred several hours before mitochondrial clearance, with lipid droplets bordering mitochondria upon iron chelation. We demonstrate that DGAT1 inhibition restricts mitophagy in vitro, with impaired lysosomal homeostasis and cell viability. Importantly, genetic depletion of DGAT1 in vivo significantly impaired neuronal mitophagy and locomotor function in Drosophila. Our data define iron depletion as a potent signal that rapidly reshapes metabolism and establishes an unexpected synergy between lipid homeostasis and mitophagy that safeguards cell and tissue integrity.

Gate-tuneable and chirality-dependent charge-to-spin conversion in tellurium nanowires.

Chiral materials are an ideal playground for exploring the relation between symmetry, relativistic effects and electronic transport. For instance, chiral organic molecules have been intensively studied to electrically generate spin-polarized currents in the last decade, but their poor electronic conductivity limits their potential for applications. Conversely, chiral inorganic materials such as tellurium have excellent electrical conductivity, but their potential for enabling the electrical control of spin polarization in devices remains unclear. Here, we demonstrate the all-electrical generation, manipulation and detection of spin polarization in chiral single-crystalline tellurium nanowires. By recording a large (up to 7%) and chirality-dependent unidirectional magnetoresistance, we show that the orientation of the electrically generated spin polarization is determined by the nanowire handedness and uniquely follows the current direction, while its magnitude can be manipulated by an electrostatic gate. Our results pave the way for the development of magnet-free chirality-based spintronic devices.

Mapping spin-charge conversion to the band structure in a topological oxide two-dimensional electron gas.

While spintronics has traditionally relied on ferromagnetic metals as spin generators and detectors, spin-orbitronics exploits the efficient spin-charge interconversion enabled by spin-orbit coupling in non-magnetic systems. Although the Rashba picture of split parabolic bands is often used to interpret such experiments, it fails to explain the largest conversion effects and their relationship with the electronic structure. Here, we demonstrate a very large spin-to-charge conversion effect in an interface-engineered, high-carrier-density SrTiO3 two-dimensional electron gas and map its gate dependence on the band structure. We show that the conversion process is amplified by enhanced Rashba-like splitting due to orbital mixing and in the vicinity of avoided band crossings with topologically non-trivial order. Our results indicate that oxide two-dimensional electron gases are strong candidates for spin-based information readout in new memory and transistor designs. Our results also emphasize the promise of topology as a new ingredient to expand the scope of complex oxides for spintronics.

A metabolite roadmap of the wood-forming tissue in Populus tremula.

Wood, or secondary xylem, is the product of xylogenesis, a developmental process that begins with the proliferation of cambial derivatives and ends with mature xylem fibers and vessels with lignified secondary cell walls. Fully mature xylem has undergone a series of cellular processes, including cell division, cell expansion, secondary wall formation, lignification and programmed cell death. A complex network of interactions between transcriptional regulators and signal transduction pathways controls wood formation. However, the role of metabolites during this developmental process has not been comprehensively characterized. To evaluate the role of metabolites during wood formation, we performed a high spatial resolution metabolomics study of the wood-forming zone of Populus tremula, including laser dissected aspen ray and fiber cells. We show that metabolites show specific patterns within the wood-forming zone, following the differentiation process from cell division to cell death. The data from profiled laser dissected aspen ray and fiber cells suggests that these two cell types host distinctly different metabolic processes. Furthermore, by integrating previously published transcriptomic and proteomic profiles generated from the same trees, we provide an integrative picture of molecular processes, for example, deamination of phenylalanine during lignification is of critical importance for nitrogen metabolism during wood formation.

Predictors of contraceptive use among female adolescents in Ghana.

Adolescent girls in Ghana still face a number of challenges accessing reproductive/sexual health services despite efforts to improve their accessibility. This paper explores the key socio-demographic factors associated with contraceptive use amongst adolescent girls in Ghana using the 2008 Ghana Demographic and Health Survey (GDHS). Data from the 2008 GDHS was analyzed. Socio-demographic variables were selected to assess their interaction with contraceptive use. Multivariable regression analyses were performed. Odds ratios and confidence intervals were computed. Place of residence and marital status were the most important predictors of contraceptive use among sexually active adolescents. Rural residents were less likely to use contraceptives compared to urban residents (OR 0.32, CI 0.12-0.84, p = 0.021) as well as married respondents compared to their unmarried peers (OR 0.27, 95% CI 0.11-0.67, p = 0.005). The accessibility of reproductive/sexual health services needs to be improved and promoted in rural areas and among married adolescent women.

Theory of spin and orbital Edelstein effects.

In systems with broken spatial inversion symmetry, such as surfaces, interfaces, or bulk systems lacking an inversion center, the application of a charge current can generate finite spin and orbital densities associated with a nonequilibrium magnetization, which is known as spin and orbital Edelstein effect (SEE and OEE), respectively. Early reports on this current-induced magnetization focus on two-dimensional Rashba systems, in which an in-plane nonequilibrium spin density is generated perpendicular to the applied charge current. However, until today, a large variety of materials have been theoretically predicted and experimentally demonstrated to exhibit a sizeable Edelstein effect, which comprises contributions from the spin as well as the orbital degrees of freedom, and whose associated magnetization may be out of plane, nonorthogonal, and even parallel to the applied charge current, depending on the system's particular symmetries. In this review, we give an overview on the most commonly used theoretical approaches for the discussion and prediction of the SEE and OEE. Further, we introduce a selection of the most intensely discussed materials exhibiting a finite Edelstein effect, and give a brief summary of common experimental techniques.

OnPLS integration of transcriptomic, proteomic and metabolomic data shows multi-level oxidative stress responses in the cambium of transgenic hipI- superoxide dismutase Populus plants.

BACKGROUND: Reactive oxygen species (ROS) are involved in the regulation of diverse physiological processes in plants, including various biotic and abiotic stress responses. Thus, oxidative stress tolerance mechanisms in plants are complex, and diverse responses at multiple levels need to be characterized in order to understand them. Here we present system responses to oxidative stress in Populus by integrating data from analyses of the cambial region of wild-type controls and plants expressing high-isoelectric-point superoxide dismutase (hipI-SOD) transcripts in antisense orientation showing a higher production of superoxide. The cambium, a thin cell layer, generates cells that differentiate to form either phloem or xylem and is hypothesized to be a major reason for phenotypic perturbations in the transgenic plants. Data from multiple platforms including transcriptomics (microarray analysis), proteomics (UPLC/QTOF-MS), and metabolomics (GC-TOF/MS, UPLC/MS, and UHPLC-LTQ/MS) were integrated using the most recent development of orthogonal projections to latent structures called OnPLS. OnPLS is a symmetrical multi-block method that does not depend on the order of analysis when more than two blocks are analysed. Significantly affected genes, proteins and metabolites were then visualized in painted pathway diagrams. RESULTS: The main categories that appear to be significantly influenced in the transgenic plants were pathways related to redox regulation, carbon metabolism and protein degradation, e.g. the glycolysis and pentose phosphate pathways (PPP). The results provide system-level information on ROS metabolism and responses to oxidative stress, and indicate that some initial responses to oxidative stress may share common pathways. CONCLUSION: The proposed data evaluation strategy shows an efficient way of compiling complex, multi-platform datasets to obtain significant biological information.

The UCLA Cosmochemistry Database.

The UCLA Cosmochemistry Database was initiated as part of a data-rescue and -storage project aimed at archiving a variety of cosmochemical data acquired at University of California, Los Angeles (UCLA). The data collection includes elemental compositions of extraterrestrial materials analyzed by UCLA cosmochemists over the last five decades. The analytical techniques include atomic absorption spectrometry (AAS) and neutron activation analysis (NAA) at UCLA. The data collection is stored on the Astromaterials Data System (Astromat). We provide both interactive tables and downloadable datasheets for users to access all data. The UCLA Cosmochemistry Database archives cosmochemical data that are essential tools for increasing our understanding of the nature and origin of extraterrestrial materials. Future studies can reference the data collection in the examination, analysis, and classification of newly acquired extraterrestrial samples.

Formate overflow drives toxic folate trapping in MTHFD1 inhibited cancer cells.

Cancer cells fuel their increased need for nucleotide supply by upregulating one-carbon (1C) metabolism, including the enzymes methylenetetrahydrofolate dehydrogenase-cyclohydrolase 1 and 2 (MTHFD1 and MTHFD2). TH9619 is a potent inhibitor of dehydrogenase and cyclohydrolase activities in both MTHFD1 and MTHFD2, and selectively kills cancer cells. Here, we reveal that, in cells, TH9619 targets nuclear MTHFD2 but does not inhibit mitochondrial MTHFD2. Hence, overflow of formate from mitochondria continues in the presence of TH9619. TH9619 inhibits the activity of MTHFD1 occurring downstream of mitochondrial formate release, leading to the accumulation of 10-formyl-tetrahydrofolate, which we term a 'folate trap'. This results in thymidylate depletion and death of MTHFD2-expressing cancer cells. This previously uncharacterized folate trapping mechanism is exacerbated by physiological hypoxanthine levels that block the de novo purine synthesis pathway, and additionally prevent 10-formyl-tetrahydrofolate consumption for purine synthesis. The folate trapping mechanism described here for TH9619 differs from other MTHFD1/2 inhibitors and antifolates. Thus, our findings uncover an approach to attack cancer and reveal a regulatory mechanism in 1C metabolism.

Married men's first time experiences of early childbearing and their role in sexual and reproductive decision making: a qualitative study from rural Vietnam.

Male partners' involvement in women's sexual and reproductive health has been increasingly emphasised in international health. A qualitative approach with open-ended qualitative interviews was used to explore young, married men's first time experiences of early childbearing, their sexual and reproductive decision making and the meanings they make of their role as husbands and fathers. The results offer a nuanced picture of the men's vulnerability in becoming young fathers and having to assume their role as family decision-makers, while still being inexperienced in matters related to the health of their wives and newborn child. Constraints to gender equality and traditional norms and values continue to pose barriers to both young men and women making independent decisions in relation to marriage and childbearing. Men's involvement is necessary in healthcare programmes designed to improve women's sexual and reproductive health and the health of the newborn. Young, first-time fathers, in particular, need support and empowerment.

Comparative structural analysis provides new insights into the function of R2-like ligand-binding oxidase.

R2-like ligand-binding oxidase (R2lox) is a ferritin-like protein that harbours a heterodinuclear manganese-iron active site. Although R2lox function is yet to be established, the enzyme binds a fatty acid ligand coordinating the metal centre and catalyses the formation of a tyrosine-valine ether cross-link in the protein scaffold upon O2 activation. Here, we characterized the ligands copurified with R2lox by mass spectrometry-based metabolomics. Moreover, we present the crystal structures of two new homologs of R2lox, from Saccharopolyspora erythraea and Sulfolobus acidocaldarius, at 1.38 Å and 2.26 Å resolution, respectively, providing the highest resolution structure for R2lox, as well as new insights into putative mechanisms regulating the function of the enzyme.

Direct visualization of Rashba-split bands and spin/orbital-charge interconversion at KTaO3 interfaces.

Rashba interfaces have emerged as promising platforms for spin-charge interconversion through the direct and inverse Edelstein effects. Notably, oxide-based two-dimensional electron gases display a large and gate-tunable conversion efficiency, as determined by transport measurements. However, a direct visualization of the Rashba-split bands in oxide two-dimensional electron gases is lacking, which hampers an advanced understanding of their rich spin-orbit physics. Here, we investigate KTaO3 two-dimensional electron gases and evidence their Rashba-split bands using angle resolved photoemission spectroscopy. Fitting the bands with a tight-binding Hamiltonian, we extract the effective Rashba coefficient and bring insight into the complex multiorbital nature of the band structure. Our calculations reveal unconventional spin and orbital textures, showing compensation effects from quasi-degenerate band pairs which strongly depend on in-plane anisotropy. We compute the band-resolved spin and orbital Edelstein effects, and predict interconversion efficiencies exceeding those of other oxide two-dimensional electron gases. Finally, we suggest design rules for Rashba systems to optimize spin-charge interconversion performance.

A metabolomic approach to study major metabolite changes during acclimation to limiting CO2 in Chlamydomonas reinhardtii.

Using a gas chromatography-mass spectrometry-time of flight technique, we determined major metabolite changes during induction of the carbon-concentrating mechanism in the unicellular green alga Chlamydomonas reinhardtii. In total, 128 metabolites with significant differences between high- and low-CO(2)-grown cells were detected, of which 82 were wholly or partially identified, including amino acids, lipids, and carbohydrates. In a 24-h time course experiment, we show that the amino acids serine and phenylalanine increase transiently while aspartate and glutamate decrease after transfer to low CO(2). The biggest differences were typically observed 3 h after transfer to low-CO(2) conditions. Therefore, we made a careful metabolomic examination at the 3-h time point, comparing low-CO(2) treatment to high-CO(2) control. Five metabolites involved in photorespiration, 11 amino acids, and one lipid were increased, while six amino acids and, interestingly, 21 lipids were significantly lower. Our conclusion is that the metabolic pattern during early induction of the carbon-concentrating mechanism fit a model where photorespiration is increasing.

Prematurely ended phase III trials in Sweden during the years 2002-2008.

PURPOSE: The aim of this study was to identify prematurely ended phase III clinical trials (CTs) and the proportion of such trials among all phase III CTs, review the reasons for the premature discontinuation of the CT, determine whether a data monitoring committee (DMC) was involved in this decision-making process, identify the data source on which the decision was based and review the consequences of the premature ending for product development. An additional aim was to identify risk factors for a premature ending. METHODS: Prematurely ended phase III CTs in Sweden between 2002 and 2008 were identified by database searches. Identified trials were reviewed for treatment tested, study design, reasons for the premature ending, data source on which the decision was based and existence of and recommendation from a DMC. Three randomly selected but not prematurely ended control trials were identified, starting 1 May 2004, that were matched on the basis of application year. RESULTS: A total of 84 phase III CT applications (8%) were prematurely ended during the study period. Most trials were ended due to safety and/or efficacy concerns. A DMC was more common among trials in which mortality was the primary endpoint and oncology trials. A recommendation from the DMC to terminate the trial was most likely in the case of combined safety- and efficacy-related issues arising from within the trial. Possible risk factors for a premature ending included mortality as an endpoint, obesity as an indication and a longer than planned study duration. Approximately 30% of prematurely ended trials with active substances that did not have a marketing authorization at the time of the clinical trial application resulted in the discontinuation of further development of the substance. CONCLUSIONS: The DMCs in the phase III CTs reviewed here were used in accordance with guidelines. The use of DMCs was associated with possible risk factors for a premature ending and numerically, but not significantly associated with a premature ending.

Trends in contraceptive use among female adolescents in Ghana.

Within the past one and half decades many efforts have been made to improve the availability and access to adolescent sexual and reproductive health services. Despite these efforts, adolescents still face a number of sexual and reproductive health problems. This paper uses data from the 2003 and 2008 Ghana Demographic and Health Surveys to examine changes in contraceptive use among sexually active female adolescents (15-19 years old). The results show that between 2003 and 2008 there was a significant increase in the current use of any contraceptive method (from 23.7% to 35.1%, p = 0.03). It also indicates a shift from modern to traditional contraceptive methods. Traditional methods recorded about 60% (7.8 percentage points) increase as compared to 5.5% (2.6 percentage points) for modern methods. Also ever use of any traditional method recorded a higher increase as compared to any modem method. There was a slight decline 7% (4.4 parentage points) in the number of non-users who intended to use contraceptives in the future. On the whole the findings indicate increasing unmet need for modern contraception due to barriers such as limited access, cost and misconceptions about the effects of contraceptives.

Obstetric brachial plexus palsy: a prospective, population-based study of incidence, recovery, and residual impairment at 18 months of age.

AIM: The aim of this investigation was to study the incidence of obstetric brachial plexus palsy (OBPP), to prospectively follow the recovery process, to assess the functional outcome at 18 months of age, and to find early prognostic indicators. METHOD: Of the 38 749 children born between 1999 and 2001 in western Sweden, 114 (70 males, 44 females) had an OBPP. Ninety-eight children were examined on six occasions at up to 18 months of age. Muscle strength, range of motion, hand preference, and functional abilities were noted, and the severity of the OBPP was classified. RESULTS: The incidence of OBPP was 2.9 per 1000 live births, and the incidence of persisting OBPP was 0.46 per 1000. At 3 months of age, the predictive value of regained elbow flexion for complete recovery was 100%, 99% of shoulder external rotation, and 96% of forearm supination. Most of the 18 children with persisting OBPP could perform functional activities but asymmetries were noted. Five children had a mild, 11 had a moderate, and two had a severe impairment. Three had undergone nerve surgery, one with a mild and two with a severe persisting impairment. INTERPRETATION: Most children with an OBPP recover completely. Muscle strength at 3 months of age can be used to predict outcome.

A five-year follow-up study of Swedish adults with gender identity disorder.

This follow-up study evaluated the outcome of sex reassignment as viewed by both clinicians and patients, with an additional focus on the outcome based on sex and subgroups. Of a total of 60 patients approved for sex reassignment, 42 (25 male-to-female [MF] and 17 female-to-male [FM]) transsexuals completed a follow-up assessment after 5 or more years in the process or 2 or more years after completed sex reassignment surgery. Twenty-six (62%) patients had an early onset and 16 (38%) patients had a late onset; 29 (69%) patients had a homosexual sexual orientation and 13 (31%) patients had a non-homosexual sexual orientation (relative to biological sex). At index and follow-up, a semi-structured interview was conducted. At follow-up, 32 patients had completed sex reassignment surgery, five were still in process, and five-following their own decision-had abstained from genital surgery. No one regretted their reassignment. The clinicians rated the global outcome as favorable in 62% of the cases, compared to 95% according to the patients themselves, with no differences between the subgroups. Based on the follow-up interview, more than 90% were stable or improved as regards work situation, partner relations, and sex life, but 5-15% were dissatisfied with the hormonal treatment, results of surgery, total sex reassignment procedure, or their present general health. Most outcome measures were rated positive and substantially equal for MF and FM. Late-onset transsexuals differed from those with early onset in some respects: these were mainly MF (88 vs. 42%), older when applying for sex reassignment (42 vs. 28 years), and non-homosexually oriented (56 vs. 15%). In conclusion, almost all patients were satisfied with the sex reassignment; 86% were assessed by clinicians at follow-up as stable or improved in global functioning.

Perinatal services and outcomes in Quang Ninh province, Vietnam.

AIM: We report baseline results of a community-based randomized trial for improved neonatal survival in Quang Ninh province, Vietnam (NeoKIP; ISRCTN44599712). The NeoKIP trial seeks to evaluate a method of knowledge implementation called facilitation through group meetings at local health centres with health staff and community key persons. Facilitation is a participatory enabling approach that, if successful, is well suited for scaling up within health systems. The aim of this baseline report is to describe perinatal services provided and neonatal outcomes. METHODS: Survey of all health facility registers of service utilization, maternal deaths, stillbirths and neonatal deaths during 2005 in the province. Systematic group interviews of village health workers from all communes. A Geographic Information System database was also established. RESULTS: Three quarters of pregnant women had ≥3 visits to antenatal care. Two hundred and five health facilities, including 18 hospitals, provided delivery care, ranging from 1 to 3258 deliveries/year. Totally there were 17 519 births and 284 neonatal deaths in the province. Neonatal mortality rate was 16/1000 live births, ranging from 10 to 44/1000 in the different districts, with highest rates in the mountainous parts of the province. Only 8% had home deliveries without skilled attendance, but those deliveries resulted in one-fifth of the neonatal deaths. CONCLUSION: A relatively good coverage of perinatal care was found in a Vietnamese province, but neonatal mortality varied markedly with geography and level of care. A remaining small proportion of home deliveries generated a substantial part of mortality.

Unconventional Charge-Spin Conversion in Weyl-Semimetal WTe2.

An outstanding feature of topological quantum materials is their novel spin topology in the electronic band structures with an expected large charge-to-spin conversion efficiency. Here, a charge-current-induced spin polarization in the type-II Weyl semimetal candidate WTe2 and efficient spin injection and detection in a graphene channel up to room temperature are reported. Contrary to the conventional spin Hall and Rashba-Edelstein effects, the measurements indicate an unconventional charge-to-spin conversion in WTe2 , which is primarily forbidden by the crystal symmetry of the system. Such a large spin polarization can be possible in WTe2 due to a reduced crystal symmetry combined with its large spin Berry curvature, spin-orbit interaction with a novel spin-texture of the Fermi states. A robust and practical method is demonstrated for electrical creation and detection of such a spin polarization using both charge-to-spin conversion and its inverse phenomenon and utilized it for efficient spin injection and detection in the graphene channel up to room temperature. These findings open opportunities for utilizing topological Weyl materials as nonmagnetic spin sources in all-electrical van der Waals spintronic circuits and for low-power and high-performance nonvolatile spintronic technologies.

Lipid accumulation controls the balance between surface connection and scission of caveolae.

Caveolae are bulb-shaped invaginations of the plasma membrane (PM) that undergo scission and fusion at the cell surface and are enriched in specific lipids. However, the influence of lipid composition on caveolae surface stability is not well described or understood. Accordingly, we inserted specific lipids into the cell PM via membrane fusion and studied their acute effects on caveolae dynamics. We demonstrate that sphingomyelin stabilizes caveolae to the cell surface, whereas cholesterol and glycosphingolipids drive caveolae scission from the PM. Although all three lipids accumulated specifically in caveolae, cholesterol and sphingomyelin were actively sequestered, whereas glycosphingolipids diffused freely. The ATPase EHD2 restricts lipid diffusion and counteracts lipid-induced scission. We propose that specific lipid accumulation in caveolae generates an intrinsically unstable domain prone to scission if not restrained by EHD2 at the caveolae neck. This work provides a mechanistic link between caveolae and their ability to sense the PM lipid composition.