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This paper examines the effect of the government college loan program in Korea on student academic performance, dropout decisions and loan defaults. While fairness in educational opportunities has been guaranteed to some degree through this program, which started in 2009, there has been a great deal of controversy over its effectiveness. Empirical findings suggest that recipients of general student loan (GSL) lower academic performance than those who received income contingent loan (ICL). Moreover, for students attending private universities, a higher number of loans received increased the probability of a dropout decision, and students from middle-income households had a higher probability of being overdue than students from low-income households. These findings indicate that expanding the ICL program within the allowance of the government budget is necessary. Furthermore, providing opportunities for students to find various jobs and introducing a rating system for defaulters are two necessary tasks.

This study empirically analyzes changes in production patterns of farmers by agricultural disaster insurance. The aim of this project is to achieve stability of farm management by paying insurance in case of a natural disaster. However, it causes farmers to change production patterns in the direction of increasing production, and leads the crop price to drop. This can be explained by producers’ risk reduction through the disaster insurance. The empirical analysis is based on Ⅳ approach with using two stage least squares method. The first stage estimates by difference-in-differences methodology indicate that the production of insurable crops increases more about 80,000ton on average than that of non-insurable crops. In addition, to solve the endogeneity problem caused by general supply and demand model, I use the first stage estimates and find that the price index of the crops drops about 2.3% according to the production increase by 10,000ton. The credibility of these results is also attained by various robustness checks. These findings suggest that it is necessary for government to analyze the whole economy which consists of producer and consumer welfare when it determines the policy. Besides, it implies that it is essential to develop a new market to cope with the unintended effect.

The objective of this study was to devise effective safety management systems for enclosed living modified organism (LMO) fields regulated by the Ministry of Environment (MOE), achieved through an assessment of the impact of LM crops on the surrounding flora. A combination of conventional survey methods and cutting-edge drone-based monitoring systems was employed, with a keen focus on their efficacy. Our investigation spans three distinct zones (forest, non-forest, and enclosed field), involving vegetation surveys, biodiversity index analyses, and drone-powered aerial observations to study topographical shifts. Over time, wild plants adjacent to the enclosed LMO field exhibited stability in terms of species composition. Nevertheless, disparities in growth patterns emerged across various areas. Predominantly, herbs thrived in enclosed and non-forest areas, while trees and shrubs flourished in forested regions. Annual plants predominantly populated the non-forest regions, whereas perennials dominated the forested areas. To this end, drones captured aerial photographs of a 31.65-hectare expanse with 40% coverage overlap, furnishing a real-time vegetation map that transcends the capacities of conventional methods. By combining vegetation surveys, drone-generated vegetation mapping, and dynamic monitoring of topographical changes, our research endeavors to facilitate the formulation of a robust safety management framework for LMO confined fields overseen by the MOE. This holistic approach aspires to prevent ecosystem contamination and establish a resilient, enduring system that averts LMO leakage, thereby safeguarding the environment. [ABSTRACT FROM AUTHOR]

Do political leaders influence the level of economic inequality in authoritarian countries? Building on previous studies on political leaders and authoritarian regimes, we argue that economic inequality is likely to decrease during the tenure of authoritarian leaders with personal experiences of economic hardship. Since authoritarian leaders have greater policy discretion than their democratic counterparts, their policy choices are less constrained by other political actors and institutions. As their material background makes authoritarian leaders more likely to favour introducing redistributive measures, they are expected to use such strategies for political survival, leading to a decrease in economic inequality. We created and analysed a new dataset on political leaders' socioeconomic backgrounds in authoritarian regimes and found support for our arguments. In line with recent studies on political leaders and policy outcomes, our findings suggest that leaders' personal experiences of economic hardship greatly affect their policy choices in authoritarian countries. [ABSTRACT FROM AUTHOR]

While political leaders' role in foreign policy choices has received increasing scholarly attention, surprisingly less is known about how they affect the allocation and distribution of official development aid. This study examines how the material background of political leaders influences their aid allocation strategies in donor countries. We contend that leaders with economic hardship experience distribute more foreign aid than those without such experience. Through socialization, leaders with economic hardship experience become more supportive of public good provisions that address problems related to poverty and inequality. Resultantly, they exhibit more favorable attitudes toward development assistance programs targeting developing countries. We find that political leaders who experienced economic difficulty in their youth are likely to provide more foreign aid, especially social and economic infrastructure aid, than leaders without such experience. By introducing the political leaders' role, this study contributes to the literature on the interaction between domestic politics and foreign aid. [ABSTRACT FROM AUTHOR]

Objectives: We attempt to examine how union membership affects redistributive attitudes. We argue that the impact of union membership on support for redistributive policies is conditional on the economic inequality between the union and nonunion members (between group inequality [BGI]). When BGI is high, unions have less incentive to emphasize the solidaristic redistributive norm because the majority of union members would not be the beneficiaries of government redistribution. Methods: We employ multilevel modeling using the International Social Survey Programme (ISSP) datasets that cover 39 countries between 1985 and 2010. Results: We find that the positive effect of union membership on individual support for redistributive policies decreases as the level of BGI increases. Conclusion: Our study demonstrates the importance of group‐level inequality as the contextual factor in explaining the nexus between union membership and preferences for government redistribution. It also suggests that unions play a substantial role in shaping members' attitudes toward government policies in general. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2010.03.026 Byline: Youfeng Yang, Sung Min Han, Michael A. Miller Keywords: MSP; MAP kinase; Oocyte maturation; Shp; RasGAP; Ras; Fertilization; SOD1; Amyotrophic lateral sclerosis; VAPB; Reactive oxygen species Abstract: The MSP domain is a conserved immunoglobulin-like structure that is important for C. elegans reproduction and human motor neuron survival. C. elegans MSPs are the most abundant proteins in sperm, where they function as intracellular cytoskeletal proteins and secreted hormones. Secreted MSPs bind to multiple receptors on oocyte and ovarian sheath cell surfaces to induce oocyte maturation and sheath contraction. MSP binding stimulates oocyte MPK-1 ERK MAP Kinase (MAPK) phosphorylation, but the function and mechanism are not well understood. Here we show that the Shp class protein-tyrosine phosphatase PTP-2 acts in oocytes downstream of sheath/oocyte gap junctions to promote MSP-induced MPK-1 phosphorylation. PTP-2 functions in the oocyte cytoplasm, not at the cell surface to inhibit multiple RasGAPs, resulting in sustained Ras activation. We also provide evidence that MSP promotes production of reactive oxygen species (ROS), which act as second messengers to augment MPK-1 phosphorylation. The Cu/Zn superoxide dismutase SOD-1, an enzyme that catalyzes ROS breakdown in the cytoplasm, inhibits MPK-1 phosphorylation downstream of or in parallel to ptp-2. Our results support the model that MSP triggers PTP-2/Ras activation and ROS production to stimulate MPK-1 activity essential for oocyte maturation. We propose that secreted MSP domains and Cu/Zn superoxide dismutases function antagonistically to control ROS and MAPK signaling. Author Affiliation: Department of Cell Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA Article History: Received 27 October 2009; Revised 12 March 2010; Accepted 31 March 2010

Do voters punish left‐wing parties that pursue neo‐liberal policies? We address the question in the context of post‐communist countries, where the left implemented significant and painful market‐oriented reforms. For the left, owning these reforms means backing away from its popular image and policy platform and plausibly generates two electorally consequential outcomes: a 'brand dilution' effect that weakens voters' attachment to left parties and is magnified by the economic vulnerability of the left's core constituency; and an 'expectations effect' that increases demand for right‐wing politicians. Overall, the left should lose votes, particularly when voters can easily attribute responsibility for policies. Our analysis uses updated data on the vote shares for all parties and elections in post‐communist democracies from 1991 to 2010. We find support for the theory: Incumbent left‐wing parties of the chief executive are punished at the ballot box for moving to the right on economic policy. This, likely, comes from a 'brand dilution' effect, as we find that such vote losses feed the fortunes of non‐incumbent left‐wing and populist parties. [ABSTRACT FROM AUTHOR]

This study analyzes how political leaders' material backgrounds affect redistributive policies in democracies. Building on political socialization theory, we argue that politicians with personal experience of economic hardship are more likely to have sympathetic attitudes toward redistribution than those without such experience, particularly where political constraints are weak. We posit that firsthand knowledge of economic hardship helps political leaders understand why the poor need government redistribution, and leads them to support more generous social welfare policies. Analyzing an original dataset of leaders' material background in 74 democratic countries between 1980 and 2011, we find that leaders who experienced economic hardship in their youth increase social welfare spending during their tenure, particularly when political constraints are weak. Following prior studies on leaders' personal experiences and policy outcomes, this study provides a new approach to redistribution and welfare policy. [ABSTRACT FROM AUTHOR]

Objective: The association between sudden sensorineural hearing loss (SSNHL) and radiological findings of the vertebrobasilar artery is not well-known and little research has been done. We hypothesized that the radiological features of the vertebrobasilar artery contribute to the incidence and prognosis of SSNHL.Methods: We retrospectively enrolled patients diagnosed with unilateral SSNHL (SSNHL group) and those with acute vestibular neuritis (AVN; control group) in our hospital. All patients underwent magnetic resonance imaging and computed tomography. We measured the following parameters on the radiological images: basilar artery diameter, direction and distance of basilar artery deviation, direction and distance of vertebral artery deviation, and incidence of vertebral artery obstruction. Pure tone audiometry (PTA) was performed in all patients. Follow up PTA between 1 week and 1 month after treatment was performed in the SSNHL group.Results: A total of 244 SSNHL patients and 62 AVN patients were included in the analysis. Age, body mass index, and basilar artery diameter were found to be significantly associated with SSNHL. In the SSNHL group, patients were divided into three subgroups based on the consistency between the basilar artery deviation site and disease site. No significant difference was noted in initial PTA, final PTA, PTA recovery, and symptom improvement among the three groups. In case of the basilar artery, when the deviation and disease sites were in the opposite direction and the basilar artery diameter was >3.5 mm, diameter of basilar artery was positively correlated with PTA recovery.Conclusions: The strength of this study is that radiological evaluation of the vertebrobasilar artery was performed. Further research on the association between SSNHL and radiological features of the vertebrobasilar artery should be conducted to emphasize the importance of vascular assessment in SSNHL. [ABSTRACT FROM AUTHOR]

Proteotoxic stress is a common challenge for all organisms. Among various mechanisms involved in defending such stress, the evolutionarily conserved unfolded protein responses (UPRs) play a key role across species. Interestingly, UPRs can occur in different subcellular compartments including the endoplasmic reticulum (UPRER), mitochondria (UPRMITO), and cytoplasm (UPRCYTO) through distinct mechanisms. While previous studies have shown that the UPRs are intuitively linked to organismal aging, a systematic assay on the temporal regulation of different type of UPRs during aging is still lacking. Here, using Caenorhabditis elegans (C. elegans) as the model system, we found that the endogenous UPRs (UPRER, UPRMITO, and UPRCYTO) elevate with age, but their inducibility exhibits an age‐dependent decline. Moreover, we revealed that the temporal requirements to induce different types of UPRs are distinct. Namely, while the UPRMITO can only be induced during the larval stage, the UPRER can be induced until early adulthood and the inducibility of UPRCYTO is well maintained until mid‐late stage of life. Furthermore, we showed that different tissues may exhibit distinct temporal profiles of UPR inducibility during aging. Collectively, our findings demonstrate that UPRs of different subcellular compartments may have distinct temporal mechanisms during aging. [ABSTRACT FROM AUTHOR]

In this article, we argue that rising housing prices increase voter approval of incumbent governments because such a rise increases personal wealth, which leads to greater voter satisfaction. This effect is strongest under right-wing governments because those who benefit from rising prices—homeowners—are more likely to be right-leaning. Non-homeowners, who are more likely to vote for left-leaning parties, will view rising housing prices as a disadvantage and therefore feel the government does not serve them well, which will mitigate the advantage to left-wing governments. We find support for our arguments using both macro-level data (housing prices and government approval ratings in 16 industrialized countries between 1960 and 2017) and micro-level data (housing prices and individuals' vote choices in the United Kingdom using the British Household Panel Survey). The findings imply that housing booms benefit incumbent governments generally and right-wing ones in particular. [ABSTRACT FROM AUTHOR]

We argue that economic inequality between ethnic groups increases state repression. We contend that a high level of ethnic inequality fuels distributional conflicts between poor and rich ethnic groups. It also increases the salience of ethnic identity and promotes ethnic mobilization to challenge the status quo. This between-group tension creates collective grievances for ethnic groups, mounts challenges to incumbent governments and increases perceived threats to governments. The greater the perceived threats, the more likely that governments will employ coercive measures. We further argue that the impact of ethnic inequality on state repression is moderated by the level of democracy. Various institutional mechanisms in democracies increase the costs of repression, reducing leaders' incentives to employ coercive measures, even when facing high levels of ethnic inequality. Evidence from 152 countries between 1992 and 2011 supports our arguments. [ABSTRACT FROM AUTHOR]

Objectives: The diagnosis of primary ciliary dyskinesia (PCD) is often delayed in part related to the limitations of the available diagnostic tests. We present 3 cases of PCD diagnosed using an exhaled nitric oxide (eNO) measurement. Methods: Three cases with a clinical phenotype consistent with PCD were evaluated using an eNO assay with additional transmission electron microscopy (TEM) and/or genetic panel testing. Results: One male and 2 female patients presented with common symptoms included recurrent respiratory infection from early childhood and a history of neonatal respiratory distress as term newborn. Two of them had situs inversus totalis. Fractional eNO measurement revealed extremely low NO levels, and subsequently, TEM analysis confirmed ciliary ultrastructural defects in all patients. One patient had compound heterozygous mutation of the PCD-causative gene (DNAH5) identified using next generation sequencing. Conclusion: Our report stresses the reliability of eNO measurement in the diagnosis of PCD, accompanied by clinical phenotypes and additional diagnostic tools, such as TEM analysis and genetic testing. [ABSTRACT FROM AUTHOR]

Docetaxel, derived from the yew tree, belongs to the taxane family of medications. It works by disrupting the normal function of microtubules, thereby stopping cell division. Docetaxel is used in the treatment of ovarian, breast, esophageal, gastric, prostate, lung, and head and neck cancers. Common side effects include hair loss, low blood cell counts, peripheral neuropathy, vomiting, and muscle pain. Auricular chondritis with ear deformity has not been reported previously as a side effect of docetaxel. In this paper, we present the case of a 64-year-old male patient with chondritis accompanied by ear deformity that developed due to docetaxel–carboplatin chemotherapy for non-small cell lung cancer. [ABSTRACT FROM AUTHOR]

Purpose:Exposure to ionizing radiation induces plant defenses by regulating the expression of response genes. Thesystemic acquired resistance deficient 1(SARD1) is a key gene in plant defense response. In this study, the function ofOryza sativaSARD1 (OsSARD1) was investigated after exposure of seeds/plants to ionizing radiation, jasmonic acid (JA) or salicylic acid (SA). Materials and methods:Rice seeds exposed to two types of ionizing radiations (gamma ray [GR] and ion beam [IB]) were analyzed by quantitative reverse transcription PCR (qRT-PCR) to identify the genes that are altered in response to ionizing radiation. Then, OsSARD1-overexpressing homozygousArabidopsisplants were generated to assess the effects ofOsSARD1in the response to irradiation. The phenotypes of these transgenic plants, as well as control plants, were monitored after GR irradiation at doses of 200 and 300 Gray (Gy). Results:TheOsSARD1transcript was strongly downregulated after exposure to GR and IB irradiation. Previous phylogenetic analysis showed that theArabidopsisSARD1 (AtSARD1) protein is closely related toArabidopsiscalmodulin-binding protein 60g (AtCBP60g), which is known to be required for activation of SA biosynthesis. In this study, phylogenetic analysis showed that OsSARD1 was grouped with AtSARD1. TheOsSARD1gene was induced after exposure to SA and JA. The biological phenotype of OsSARD1-overexpressingArabidopsisplants was examined. OsSARD1-overexpressing plants displayed resistance to GR; in comparison with wild-type plants, the height and weight of OsSARD1-overexpressing plants were significantly greater after GR irradiation. In addition, OsSARD1 protein was abundantly accumulated in the nucleus. Conclusions:The results indicate thatOsSARD1plays an important role in the regulation of the defense responses to GR and IB irradiation and exhibits phytohormone induced expression. [ABSTRACT FROM AUTHOR]

Summary Axon regeneration is essential to restore the nervous system after axon injury. However, the neuronal cell biology that underlies axon regeneration is incompletely understood. Here we use in vivo, single-neuron analysis to investigate the relationship between nerve injury, mitochondrial localization, and axon regeneration. Mitochondria translocate into injured axons so that average mitochondria density increases after injury. Moreover, single-neuron analysis reveals that axons that fail to increase mitochondria have poor regeneration. Experimental alterations to axonal mitochondrial distribution or mitochondrial respiratory chain function result in corresponding changes to regeneration outcomes. Axonal mitochondria are specifically required for growth-cone migration, identifying a key energy challenge for injured neurons. Finally, mitochondrial localization to the axon after injury is regulated in part by dual-leucine zipper kinase 1 (DLK-1), a conserved regulator of axon regeneration. These data identify regulation of axonal mitochondria as a new cell-biological mechanism that helps determine the regenerative response of injured neurons. [ABSTRACT FROM AUTHOR]

This study analyses why income inequality and party polarisation proceed together in some countries but not in others. By focusing on the relationship between income inequality, the permissiveness of electoral systems and party polarisation, the study offers a theoretical explanation for how the combination of income inequality and permissive electoral systems generates higher party polarisation. After analysing a cross-national dataset of party polarisation, income inequality and electoral institutions covering 24 advanced democracies between 1960 and 2011, it is found that a simple correlation between income inequality and party polarisation is not strong. However, the empirical results indicate that greater income inequality under permissive electoral systems contributes to growing party polarisation, which suggests that parties only have diverging ideological platforms due to greater income inequality when electoral systems encourage their moves towards the extreme; parties do not diverge when electoral systems discourage their moves towards the extreme. [ABSTRACT FROM AUTHOR]

RNA ligation can regulate RNA function by altering RNA sequence, structure and coding potential. For example, the function of XBP1 in mediating the unfolded protein response requires RNA ligation, as does the maturation of some tRNAs. Here, we describe a novel in vivo model in Caenorhabditis elegans for the conserved RNA ligase Rtc B and show that Rtc B ligates the xbp-1 mRNA during the IRE-1 branch of the unfolded protein response. Without Rtc B, protein stress results in the accumulation of unligated xbp-1 mRNA fragments , defects in the unfolded protein response, and decreased lifespan. RtcB also ligates endogenous pre- tRNA halves, and Rtc B mutants have defects in growth and lifespan that can be bypassed by expression of pre-spliced tRNAs. In addition, animals that lack RtcB have defects that are independent of tRNA maturation and the unfolded protein response. Thus, RNA ligation by Rtc B is required for the function of multiple endogenous target RNAs including both xbp-1 and tRNAs. RtcB is uniquely capable of performing these ligation functions, and RNA ligation by Rtc B mediates multiple essential processes in vivo. [ABSTRACT FROM AUTHOR]

Mutations in VAPB/ALS8 are associated with amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA), two motor neuron diseases that often include alterations in energy metabolism. We have shown that C. elegans and Drosophila neurons secrete a cleavage product of VAPB, the N-terminal major sperm protein domain (vMSP). Secreted vMSPs signal through Roundabout and Lar-like receptors expressed on striated muscle. The muscle signaling pathway localizes mitochondria to myofilaments, alters their fission/fusion balance, and promotes energy production. Here, we show that neuronal loss of the C. elegans VAPB homolog triggers metabolic alterations that appear to compensate for muscle mitochondrial dysfunction. When vMSP levels drop, cytoskeletal or mitochondrial abnormalities in muscle induce elevated DAF-16, the Forkhead Box O (FoxO) homolog, transcription factor activity. DAF-16 promotes muscle triacylglycerol accumulation, increases ATP levels in adults, and extends lifespan, despite reduced muscle mitochondria electron transport chain activity. Finally, Vapb knock-out mice exhibit abnormal muscular triacylglycerol levels and FoxO target gene transcriptional responses to fasting and refeeding. Our data indicate that impaired vMSP signaling to striated muscle alters FoxO activity, which affects energy metabolism. Abnormalities in energy metabolism of ALS patients may thus constitute a compensatory mechanism counterbalancing skeletal muscle mitochondrial dysfunction. [ABSTRACT FROM AUTHOR]

Mutations in VAPB/ALS8 are associated with amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA), two motor neuron diseases that often include alterations in energy metabolism. We have shown that C. elegans and Drosophila neurons secrete a cleavage product of VAPB, the N-terminal major sperm protein domain (vMSP). Secreted vMSPs signal through Roundabout and Lar-like receptors expressed on striated muscle. The muscle signaling pathway localizes mitochondria to myofilaments, alters their fission/fusion balance, and promotes energy production. Here, we show that neuronal loss of the C. elegans VAPB homolog triggers metabolic alterations that appear to compensate for muscle mitochondrial dysfunction. When vMSP levels drop, cytoskeletal or mitochondrial abnormalities in muscle induce elevated DAF-16, the Forkhead Box O (FoxO) homolog, transcription factor activity. DAF-16 promotes muscle triacylglycerol accumulation, increases ATP levels in adults, and extends lifespan, despite reduced muscle mitochondria electron transport chain activity. Finally, Vapb knock-out mice exhibit abnormal muscular triacylglycerol levels and FoxO target gene transcriptional responses to fasting and refeeding. Our data indicate that impaired vMSP signaling to striated muscle alters FoxO activity, which affects energy metabolism. Abnormalities in energy metabolism of ALS patients may thus constitute a compensatory mechanism counterbalancing skeletal muscle mitochondrial dysfunction. [ABSTRACT FROM AUTHOR]

Summary: The VAPB/ALS8 major sperm protein domain (vMSP) is implicated in amyotrophic lateral sclerosis and spinal muscular atrophy, yet its function in the nervous system is not well understood. In Caenorhabditis elegans and Drosophila, the vMSP is cleaved from its transmembrane anchor and secreted in a cell type-specific fashion. We show that vMSPs secreted by neurons act on Lar-like protein-tyrosine phosphatase and Roundabout growth cone guidance receptors expressed in striated muscle. This signaling pathway promotes Arp2/3-dependent actin remodeling and mitochondrial localization to actin-rich muscle I-bands. C. elegans VAPB mutants have mitochondrial localization, morphology, mobility, and fission/fusion defects that are suppressed by Lar-like receptor or Arp2/3 inactivation. Hence, growth cone guidance receptor pathways that remodel the actin cytoskeleton have unanticipated effects on mitochondrial dynamics. We propose that neurons secrete vMSPs to promote striated muscle energy production and metabolism, in part through the regulation of mitochondrial localization and function. Video Abstract: Display Omitted [Copyright &y& Elsevier]

During sexual reproduction in many species, sperm and oocyte secrete diffusible signaling molecules to help orchestrate the biological symphony of fertilization. In the Caenorhabditis elegans gonad, bidirectional signaling between sperm and oocyte is important for guiding sperm to the fertilization site and inducing oocyte maturation. The molecular mechanisms that regulate sperm guidance and oocyte maturation are being delineated. Unexpectedly, these mechanisms are providing insight into human diseases, such as amyotrophic lateral sclerosis, spinal muscular atrophy, and cancer. Here we review sperm and oocyte communication in C. elegans and discuss relationships to human disorders. Developmental Dynamics 239:1265-1281, 2010. © 2009 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Iron is indispensable for normal body functions across species because of its critical roles in red blood cell function and many essential proteins and enzymes required for numerous physiological processes. Regulation of iron homeostasis is an intricate process involving multiple modulators at the systemic, cellular, and molecular levels. Interestingly, emerging evidence has demonstrated that many modulators of iron homeostasis contribute to organismal aging and longevity. On the other hand, the age-related dysregulation of iron homeostasis is often associated with multiple age-related pathologies including bone resorption and neurodegenerative diseases such as Alzheimer's disease. Thus, a thorough understanding on the interconnections between systemic and cellular iron balance and organismal aging may help decipher the etiologies of multiple age-related diseases, which could ultimately lead to developing therapeutic strategies to delay aging and treat various age-related diseases. Here we present the current understanding on the mechanisms of iron homeostasis. We also discuss the impacts of aging on iron homeostatic processes and how dysregulated iron metabolism may affect aging and organismal longevity. • Tight regulation of physiological Fe levels is essential for normal body functions • Complex systemic, cellular, and molecular mechanisms maintain Fe homeostasis • Age-associated Fe dyshomeostasis and cellular Fe deposition are hallmarks of aging • Fe dyshomeostasis accelerates cellular senescence and organismal aging in animals • Fe overload leads to multiple age-related pathologies in humans [ABSTRACT FROM AUTHOR]

Summary: VAP proteins (human VAPB/ALS8, Drosophila VAP33, and C. elegans VPR-1) are homologous proteins with an amino-terminal major sperm protein (MSP) domain and a transmembrane domain. The MSP domain is named for its similarity to the C. elegans MSP protein, a sperm-derived hormone that binds to the Eph receptor and induces oocyte maturation. A point mutation (P56S) in the MSP domain of human VAPB is associated with Amyotrophic lateral sclerosis (ALS), but the mechanisms underlying the pathogenesis are poorly understood. Here we show that the MSP domains of VAP proteins are cleaved and secreted ligands for Eph receptors. The P58S mutation in VAP33 leads to a failure to secrete the MSP domain as well as ubiquitination, accumulation of inclusions in the endoplasmic reticulum, and an unfolded protein response. We propose that VAP MSP domains are secreted and act as diffusible hormones for Eph receptors. This work provides insight into mechanisms that may impact the pathogenesis of ALS. [Copyright &y& Elsevier]

Caenorhabditis elegans germ cell proliferation and development were severely damaged in second generation dna-2 homozygotes. Even in the first generation, a much higher incidence of aberrant chromosomes in oocytes and resultantly higher embryonic lethality were found vs. wild type, when DNA breaks were induced by γ-rays or camptothecin. The deficiency of dna-2 in combination with RNA interference on mre-11 gene expression synergistically aggravated germ-line development, especially oocyte formation. These results suggest that C. elegans Dna-2 is involved in a DNA repair pathway paralleling homologous recombination or non-homologous end joining with mre-11 participation. [Copyright &y& Elsevier]

The response to gamma irradiation varies among plant species and is affected by the total irradiation dose and dose rate. In this study, we examined the immediate and ensuing responses to acute and chronic gamma irradiation in rice (Oryza sativa L.). Rice plants at the tillering stage were exposed to gamma rays for 8 h (acute irradiation) or 10 days (chronic irradiation), with a total irradiation dose of 100, 200, or 300 Gy. Plants exposed to gamma irradiation were then analyzed for DNA damage, oxidative stress indicators including free radical content and lipid peroxidation, radical scavenging, and antioxidant activity. The results showed that all stress indices increased immediately after exposure to both acute and chronic irradiation in a dose-dependent manner, and acute irradiation had a greater effect on plants than chronic irradiation. The photosynthetic efficiency and growth of plants measured at 10, 20, and 30 days post-irradiation decreased in irradiated plants, i.e., these two parameters were more severely affected by acute irradiation than by chronic irradiation. In contrast, acutely irradiated plants produced seeds with dramatically decreased fertility rate, and chronically irradiated plants failed to produce fertile seeds, i.e., reproduction was more severely affected by chronic irradiation than by acute irradiation. Overall, our findings suggest that acute gamma irradiation causes instantaneous and greater damage to plant physiology, whereas chronic gamma irradiation causes long-term damage, leading to reproductive failure. [ABSTRACT FROM AUTHOR]

In South Korea, the safety management of living modified organisms (LMOs) is regulated by seven government agencies depending on their use, and the Ministry of Environment is in charge of LMOs to manage environmental remediation and effects on natural ecosystems. This study aimed to develop appropriate research tools to determine the factors affecting the invasiveness of transgenic plants used for environmental remediation. We examined the persistence of sunflower (Helianthus annuus L.) as a candidate by comparing the seed viability at different controlled temperatures and soil depths (ranging from 0 to 30 cm). The germination characteristics of seeds significantly differed between cultivars and temperatures. The field trials indicated that seeds buried at a depth of 30 cm mostly decayed within three weeks, whereas those buried at 0 cm persisted for eight weeks but decayed after sixteen weeks, implying a significant interaction between burial depth and seed persistence. At all soil depths, no dormant seeds were detected over one week after burial. These results suggest that sunflower seeds could not be successfully established under our experimental conditions. Since seeds on the soil surface demonstrated the highest rates of germination, such seeds may require particularly careful management to prevent unintended effects on ecosystems. [ABSTRACT FROM AUTHOR]

Abstract: Asymmetric dimethylarginine (ADMA) is a risk factor of cardiovascular diseases. α-Lipoic acid (ALA) was shown to improve vascular dysfunction, and to decrease plasma ADMA level. In this study, we investigated whether ALA activates dimethylarginine dimethylaminohydrolase (DDAH), the metabolizing enzyme of ADMA, in cultured endothelial cells. ALA significantly decreased ADMA level in culture media of endothelial cells. ALA increased the gene expression and activity of DDAH, and signal transducer and activator of transcription (STAT)3 phosphorylation. Transfection of STAT3 increased DDAH II promoter activity, and ALA amplified it. ALA-induced increase in DDAH II promoter activity was attenuated in the promoter that had mutation in putative STAT3-binding site. These results suggest that ALA reduces ADMA level by enhancing DDAH activity and DDAH II gene expression, thus providing a novel mechanism by which ALA regulates endothelial function. [ABSTRACT FROM AUTHOR]