In plants, auxin functions as a master controller of development, pattern formation, morphogenesis, and tropic responses. A sophisticated transport system has evolved to allow the establishment of ...precise spatiotemporal auxin gradients that regulate specific developmental programs. A critical unresolved question relates to how these gradients can be maintained in the presence of open plasmodesmata that allow for symplasmic exchange of essential nutrients and signaling macromolecules. Here we addressed this conundrum using genetic, physiological, and cell biological approaches and identified the operation of an auxin-GSL8 feedback circuit that regulates the level of plasmodesmal-localized callose in order to locally downregulate symplasmic permeability during hypocotyl tropic response. This system likely involves a plasmodesmal switch that would prevent the dissipation of a forming gradient by auxin diffusion through the symplasm. This regulatory system may represent a mechanism by which auxin could also regulate symplasmic delivery of a wide range of signaling agents.
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•GSL8 controls plasmodesmata (PD) callose deposition, essential for tropic response•GSL8 RNAi lines show increased PD permeability and auxin diffusion via PD•Auxin-ARF7-callose-mediated PD gating is essential for tropic auxin response•Auxin could regulate symplasmic delivery of a wide range of signaling agents
How can auxin gradients be maintained in the presence of open plasmodesmata that allow for symplasmic diffusion of essential nutrients and signaling macromolecules? Han et al. report the existence of an auxin-GSL8 (callose) feedback circuit that downregulates plasmodesmal permeability, preventing the dissipation of a forming gradient by symplasmic auxin diffusion.
The 2014 US Surgeon General's report noted research gaps necessary to determine a causal relationship between active cigarette smoking and invasive breast cancer risk, including the role of alcohol ...consumption, timing of exposure, modification by menopausal status and heterogeneity by oestrogen receptor (ER) status.
To address these issues, we pooled data from 14 cohort studies contributing 934 681 participants (36 060 invasive breast cancer cases). Cox proportional hazard regression models were used to calculate multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs).
Smoking duration before first birth was positively associated with risk ( P -value for trend = 2 × 10 -7 ) with the highest HR for initiation >10 years before first birth (HR = 1.18, CI 1.12-1.24). Effect modification by current alcohol consumption was evident for the association with smoking duration before first birth ( P -value=2×10 -4 ); compared with never-smoking non-drinkers, initiation >10 years before first birth was associated with risk in every category of alcohol intake, including non-drinkers (HR = 1.15, CI 1.04-1.28) and those who consumed at least three drinks per day (1.85, 1.55-2.21). Associations with smoking before first birth were limited to risk of ER+ breast cancer ( P -value for homogeneity=3×10 -3 ). Other smoking timing and duration characteristics were associated with risk even after controlling for alcohol, but were not associated with risk in non-drinkers. Effect modification by menopause was not evident.
Smoking, particularly if initiated before first birth, was modestly associated with ER+ breast cancer risk that was not confounded by amount of adult alcohol intake. Possible links with breast cancer provide additional motivation for young women to not initiate smoking.
Summary
HIV-infected men under the age of 50 years had a lower bone mass compared to that of HIV-uninfected men. Lower CD4 T cell counts, independent of whether antiretroviral therapy (ART) was used, ...were associated with lower BMD. HIV-infected patients with low CD4 T cell counts may need follow-up and intervention regarding bone health, including younger patients.
Introduction
HIV-infected patients have a low bone mineral density (BMD) owing to multifactorial interaction between common osteoporosis risk factors and HIV-related factors, including chronic inflammation and ART. Although HIV infection and ART might affect bone metabolism, little data is available for patients aged under 50 years. We aimed to investigate the association of HIV infection-induced low CD4 T cell counts and ART with BMD in men aged under 50 years.
Methods
We performed an age- and body mass index–matched case–control study. BMD values of HIV-infected and HIV-uninfected men (< 50 years) were compared, and HIV-infected men were stratified by CD4 T cell counts and ART use.
Results
After adjusting confounders, HIV-infected men with CD4 T cell counts ≥ 500 cells/μL (
n
= 28) and < 500 cells/μL (
n
= 139) had lower BMD at the femoral neck (FN,
p
< 0.001) and total hip (TH,
p
< 0.001) than HIV-uninfected men (
n
= 167). HIV-infected men with CD4 T cell counts < 500/μL had lower BMD at the lumbar spine (LS,
p
= 0.034) than those with counts of ≥ 500 cells/μL, but not at FN and TH. The CD4 T cell count (
γ
= 0.169,
p
= 0.031) was positively correlated with BMD at LS. There was no significant difference in the BMD (
p
= 0.499–> 0.999) between the ART-naïve (
n
= 75) and ART-user group (
n
= 92).
Conclusions
Despite their relatively younger age, HIV-infected men had a lower BMD than HIV-uninfected men. Lower CD4 T cell counts, irrespective of ART, might result in lower bone mass.
The interactions between moisture and materials give rise to the possibility of moisture‐driven energy generation (MEG). Current MEG materials and devices only establish this interaction during water ...sorption in specific configurations, and conversion is eventually ceased by saturated water uptake. This paper reports an asymmetric hygroscopic structure (AHS) that simultaneously achieves energy harvesting and storage from moisture absorption. The AHS is constructed by the asymmetric deposition of a hygroscopic ionic hydrogel over a layer of functionalized carbon. Water absorbed from the air creates wet‐dry asymmetry across the AHS and hence an in‐plane electric field. The asymmetry can be perpetually maintained even after saturated water absorption. The absorbed water triggers the spontaneous development of an electrical double layer (EDL) over the carbon surface, which is termed a hygro‐ionic process, accounting for the capacitive properties of the AHS. A peak power density of 70 µW cm‐3 was realized after geometry optimization. The AHS shows the ability to be recharged either by itself owing to a self‐regeneration effect or via external electrical means, which allows it to serve as an energy storage device. In addition to insights into moisture‐material interaction, AHSs further shows potential for electronics powering in assembled devices.
An unusual route for moisture‐driven energy generation (MEG) is proposed by an asymmetric hygroscopic structure (AHS), which simultaneously achieves MEG and energy storage. The water‐absorption triggered dual function originates from the permanently maintained wet‐dry asymmetry that is formed across the AHS by the asymmetric deposition of a hygroscopic ionic hydrogel over a functionalized‐carbon layer.
Glucose metabolism is a mechanism by which energy is produced in form of adenosine triphosphate (ATP) by mitochondria and precursor metabolites are supplied to enable the ultimate enrichment of ...mature metabolites in the cell. Recently, glycolytic enzymes have been shown to have unconventional but important functions. Among these enzymes, pyruvate kinase M2 (PKM2) plays several roles including having conventional metabolic enzyme activity, and also being a transcriptional regulator and a protein kinase. Compared with the closely related PKM1, PKM2 is highly expressed in cancer cells and embryos, whereas PKM1 is dominant in mature, differentiated cells. Posttranslational modifications such as phosphorylation and acetylation of PKM2 change its cellular functions. In particular, PKM2 can translocate to the nucleus, where it regulates the transcription of many target genes. It is notable that PKM2 also acts as a protein kinase to phosphorylate several substrate proteins. Besides cancer cells and embryonic cells, astrocytes also highly express PKM2, which is crucial for lactate production via expression of lactate dehydrogenase A (LDHA), while mature neurons predominantly express PKM1. The lactate produced in cancer cells promotes tumor progress and that in astrocytes can be supplied to neurons and may act as a major source for neuronal ATP energy production. Thereby, we propose that PKM2 along with its different posttranslational modifications has specific purposes for a variety of cell types, performing unique functions.
Pyruvate kinase M2 (PKM2) is crucial for cell proliferation in embryonic and cancer cells. PKM2 has a novel function as protein kinase and transcription factor. In nucleus, PKM2 has a variety of binding proteins to regulate the expression of specific genes.
New Findings
What is the central question of this study?
Interleukin‐6 has been associated with muscle mass and metabolism in both physiological and pathological conditions. A causal role for ...interleukin‐6 in the induction of fatigue and disruption of mitochondrial function has not been determined.
What is the main finding and its importance?
We demonstrate that chronically elevated interleukin‐6 increased skeletal muscle fatigability and disrupted mitochondrial content and function independent of changes in fibre type and mass.
Interleukin‐6 (IL‐6) can initiate intracellular signalling in skeletal muscle by binding to the IL‐6‐receptor and interacting with the transmembrane gp130 protein. Circulating IL‐6 has established effects on skeletal muscle mass and metabolism in both physiological and pathological conditions. However, the effects of circulating IL‐6 on skeletal muscle function are not well understood. The purpose of this study was to determine whether chronically elevated systemic IL‐6 was sufficient to disrupt skeletal muscle force, fatigue and mitochondrial function. Additionally, we examined the role of muscle gp130 signalling during overexpression of IL‐6. Systemic IL‐6 overexpression for 2 weeks was achieved by electroporation of an IL‐6 overexpression plasmid or empty vector into the quadriceps of either C57BL/6 (WT) or skeletal muscle gp130 knockout (KO) male mice. Tibialis anterior muscle in situ functional properties and mitochondrial respiration were determined. Interleukin‐6 accelerated in situ skeletal muscle fatigue in the WT, with a 18.5% reduction in force within 90 s of repeated submaximal contractions and a 7% reduction in maximal tetanic force after 5 min. There was no difference between fatigue in the KO and KO+IL‐6. Interleukin‐6 reduced WT muscle mitochondrial respiratory control ratio by 36% and cytochrome c oxidase activity by 42%. Interleukin‐6 had no effect on either KO respiratory control ratio or cytochrome c oxidase activity. Interleukin‐6 also had no effect on body weight, muscle mass or tetanic force in either genotype. These results provide evidence that 2 weeks of elevated systemic IL‐6 is sufficient to increase skeletal muscle fatigability and decrease muscle mitochondrial content and function, and these effects require muscle gp130 signalling.
Objectives
This study aimed to scope the psychological support practices of Australian health professionals providing supportive care to adults with primary brain tumor.
Method
Health professionals ...from multidisciplinary organizations and cancer support services completed an online survey focused on psychological support for people with brain tumor (PwBT) and family members, and perceived barriers or gaps in support provision.
Results
107 professionals, mainly from psychology (45%), nursing (20%), and social work (10%) backgrounds, completed the survey. Scope of practice differed according to discipline, with psychologists and nurses most likely to screen for psychological distress (71%–76%), and psychologists more typically providing at least one psychological support session (78%). Psychologists were more likely to screen for cognitive impairment (31%), whereas nurses and social workers more commonly provided family‐based support (62%–73%). Psychological support was more frequently provided in the long‐term management phase (78%) than early post‐diagnosis/treatment (45%). System‐level barriers to accessing psychological support were most frequently identified, which included limited resources and funding, insufficient staff time, lengthy waitlists and costs, poor service coordination, and lack of staff with brain tumor‐specific training.
Conclusions
The provision of psychological support for PwBT varies according to discipline, setting and management phase. Further research on different models of psychosocial care is needed to inform strategies to address organizational and policy factors impacting professionals' scope of practice.
BioPsychoSocial health promotion is increasingly emphasized for Successful Ageing. Few programs are known to target BioPsychoSocial health of older adults and their community. The Community for ...Successful Ageing: Community Development program (ComSA CD) was developed in Singapore for this purpose.
This study assessed program effects on BioPsychoSocial health and civic engagement behaviours of participants. ComSA CD offered self-care healthy lifestyle education (Bio-physical), guided autobiography (Psychological) and a civic engagement component which galvanized participants to solve community issues (Social). Recruitment occurred through self-care or guided autobiography; following which participants were funnelled into the civic engagement component.
A mixed-methods quasi-experimental evaluation was conducted, using a pre-post one-year survey (N=232) with those exposed and unexposed (rejected) to ComSA CD. Using a generalized linear model, associations between post one-year BioPsychoSocial outcomes and exposure group were quantified using percentage change, adjusting for baseline outcome and group differences. Concurrently, program effects were explored through six focus groups with program implementers and participants using thematic analysis.
The program had multiple positive effects. Participants recruited via self-care also taking part in civic engagement reported 31% higher frequency of self-care (95% CI=21% to 68%) post one-year compared to unexposed participants. Qualitative findings illustrated how the civic engagement component stimulated agency of participants to push for neighborhood changes and civic engagement initiatives. The quantitative survey highlighted that this effect was strongest among those funnelled from guided-autobiography (92% higher frequency of civic engagement at post one-year than unexposed; 95%CI=41% to 178%) compared to those funnelled from self-care (53% higher than unexposed, 95%CI=17% to 114%). It was found qualitatively that guided-autobiography enabled more meaningful bonding and communication than the self-care component, explaining quantitative effects on social support only present among guided autobiography participants (36% higher than unexposed; 95%CI=11% to 68%). Findings highlighted the importance of improving group dynamics for collective action.
•Few known programs target BioPsychoSocial health of seniors and their community.•The study evaluated a BioPsychoSocial community development program for seniors.•The program stimulated agency of seniors to push for neighborhood changes.•This effect was strongest among those who earlier bonded in a life review component.•Findings highlight the importance of positive group dynamics for collective action.
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•Modified carbon nanotube by nano CaO2 was fist prepared and optimized by an in-situ method.•H2O2 could be released with a maximum -O-O- concentration of 26.21 mM.•Chromate was ...chemically reduced while phosphate was adsorbed to form Ca-P complex.•A maximum adsorption capacity of 126.74 mg-P/g was obtained.•Common ions except arsenite all showed negligible effects on removal performance.
Chromate and phosphate simultaneously exist in several types of waste streams (e.g., leather tannery). Herein, we developed a new carbon nanotube (CNT) modified by the nano calcium peroxide particles in-situ formed for the treatment. The CNTs with different ratios were prepared and tested for the performance. The CNT (CNT-3) prepared by 0.5-M CaCl2 and 0.5-M H2O2 demonstrated the best performance. It had a total -O-O- group content of 5.24 ± 0.68 mmol/g, and was uniformly covered by synthesized particles with an average diameter of 20–50 nm. At a dosage of 200 mg/L, the removal efficiency of Cr(VI) and phosphate was achieved with the percentage of 81 and 99%, respectively, at a contact time of 120 min. The maximum phosphate adsorption capacity was 126.74 mg-P/g, much higher than that of many adsorbents such as the reported Ca-based, Zr-based and La-based adsorbents. Commonly existing anions (namely SO42-, CO32–, SiO32-, NO3–, and Cl-) showed negligible effects on the simultaneous removal of oxyanions. However, the presence of arsenite greatly decreased the treatment efficiencies for both oxyanions; that of fluoride had no effect on the reduction of Cr(VI), but decreased the adsorption of phosphate. Acidic condition (e.g., pH 3.0) was beneficial for the Cr(VI) removal, but caused the negative effect on the phosphate removal. The chemical and physical properties of CNT-3 were studied via several analytical approaches (e.g., BET, Zeta potential, FESEM-EDX, XRD and XPS). Cr(VI) was removed via chemical reduction to Cr(III) by H2O2 released from CaO2 on CNT-3; phosphate was adsorbed via chemical precipitation (forming hydroxyapatite (Ca10(PO4)6(OH)2)) due to the presence of calcium ion and electrostatic interaction. This research indicates CNT-3 has a great potential for treatment of wastewater containing chromate and/or phosphate oxyanions.
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