91 research outputs found
Loureirin B attenuates amiodarone-induced pulmonary fibrosis by suppression of TGFĪ²1/Smad2/3 pathway
Purpose: To investigate the therapeutic effect of loureirin B (LB) on amiodarone (AD)-induced pulmonary fibrosis (PF).Methods: Forty-eight male C57BL/6 mice, 8ā10 weeks of age, were divided into four groups (n=12). Oral administration of amiodarone hydrochloride (AD) was performed for 4 weeks to induce pulmonary fibrosis. The degree of fibrosis was assessed by Masson staining, while collagen I and Ī±-smooth muscle actin (Ī±-SMA) levels were evaluated by Western blot analysis. ELISA was used to measure the levels of cytokines TNF-Ī±, IL-1Ī², and IL-6 in bronchoalveolar lavage fluid (BALF) and lung tissue. Levels of p- Smad2, Smad2, p-Smad3 and Smad3 were determined by western blotting.Results: AD treatment increased the collagen levels and expression levels of collagen I and Ī±-smooth muscle actin (Ī±-SMA) in lung tissue and of inflammatory cytokines TNF-Ī±, IL-1Ī², and IL-6, in both bronchoalveolar lavage fluid (BALF) and lung tissue in a dose-dependent manner (p < 0.01).Furthermore, AD increased the levels of p-Smad2/3. AD-induced increases in collagen I and Ī±-SMA levels were reversed by loureirin B (LB). In addition, LB reduced AD-induced increased levels of the inflammatory cytokines TNF-Ī±, IL-1Ī², and IL-6 in both bronchoalveolar lavage fluid (BALF) and lung tissue (p < 0.01).Conclusion: These results demonstrate that LB downregulates expression of fibrosis-related proteins and suppresses AD-induced PF. The mechanism responsible for the protective effect of LB on ADinduced PF might involve inhibition of the Smad2/3 pathway. Thus, LB is a potential therapeutic agent for the management of PF.
Keywords: Amiodarone, Loureirin B, Pulmonary fibrosis, Smad, Inflammatio
Changes in the Expression of miR-381 and miR-495 Are Inversely Associated with the Expression of the MDR1 Gene and Development of Multi-Drug Resistance
Multidrug resistance (MDR) frequently develops in cancer patients exposed to chemotherapeutic agents and is usually brought about by over-expression of P-glycoprotein (P-gp) which acts as a drug efflux pump to reduce the intracellular concentration of the drug(s). Thus, inhibiting P-gp expression might assist in overcoming MDR in cancer chemotherapy. MiRNAome profiling using next-generation sequencing identified differentially expressed microRNAs (miRs) between parental K562 cells and MDR K562 cells (K562/ADM) induced by adriamycin treatment. Two miRs, miR-381 and miR-495, that were strongly down-regulated in K562/ADM cells, are validated to target the 3'-UTR of the MDR1 gene. These miRs are located within a miR cluster located at chromosome region 14q32.31, and all miRs in this cluster appear to be down-regulated in K562/ADM cells. Functional analysis indicated that restoring expression of miR-381 or miR-495 in K562/ADM cells was correlated with reduced expression of the MDR1 gene and its protein product, P-gp, and increased drug uptake by the cells. Thus, we have demonstrated that changing the levels of certain miR species modulates the MDR phenotype in leukemia cells, and propose further exploration of the use of miR-based therapies to overcome MDR.The authors would like to declare that we received funding from a commercial source, i.e. Bioplatforms Australia. This does not alter
the authors' adherence to all PLOS ONE policies on sharing data and materials
Evaluation of Natural Gas Hydrate Fault System: A Case from a Sag in Deep-Water Slope Area of the Northern South China Sea
AbstractThe fault system is one of the structural carrier systems of gas hydrate accumulation, which plays a vital role in controlling the distribution of natural gas hydrate (NGH) accumulation. The previous studies mainly focus on summarizing the vertical migration mode of high flux fluid along the fault with obvious geophysical response characteristics on the seismic profile, such as āfault with gas chimney,ā āfault with mud diapir,ā and āfault with submarine collapseā, but lack of evaluation methods for the fault carrier system. We use the X sag in the deep-water continental margin slope area of the northern South China Sea as an example to study the fault systems closely related to NGH. This paper puts to use attribute technologies, such as coherence, curvature, and fusion, to analyze the characteristics and combination of the fault systems. We discussed migration patterns and evaluation methods of dominant fault carrier systems. This research proves that the strike-slip fault system in the platform area can directly connect the gas source bed with high-quality hydrocarbon generation to the gas hydrate stability zone (GHSZ). The activity of this fault system is more conducive to the accumulation of hydrocarbon in the GHSZ. This area has a good site for pore-filling gas hydrate prospecting and a preferential favorable fault carrier system. The composite fault system, consisting of a normal dip-slip fault system and a polygonal fault system, in the slope area can jointly communicate the biogenic gas-rich reservoir. Its activity and well-migration performance are the main reasons for the submarine gas leakage and collapse. It is a secondary favorable fault carrier system in the study area. There may be massive and vein natural gas hydrate formation in fractures in the leakage passage, and pore-filled gas hydrate may exist in the submarine nonleakage area. In this work, a three-factor evaluation method of the fault carrier system is proposed for the first time. This method is of great significance for the evaluation and exploration of NGH reservoirs in the continental margin slope area of the northern South China Sea
Larger Thyroid Volume and Adequate Iodine Nutrition in Chinese Schoolchildren: Local Normative Reference Values Compared with WHO/IGN
Objective. Thyroid volume measured by ultrasound to define goiter needs reliable local thyroid volume reference from iodine-sufficient populations. The aim of this study is to explore the reference interval for normal thyroid volume in schoolchildren aged 8ā10 years from Zhejiang Province, China. Methods. A probability-proportionate-to-size sampling method was applied to select a representative sample of 1213 children aged 8ā10 years in Zhejiang Province to detect the thyroid volume, salt iodine, and urine iodine. Results. Median urinary iodine concentration in involved schoolchildren was 178.30 (125.00)āĪ¼gālā1, with the percentage of samples less than 100āĪ¼gālā1 as 12.69% and more than 300āĪ¼gālā1 as 15.25%. Thyroid volume was significantly correlated with age and anthropometric measurements independently of each other. The 97th percentile of thyroid volume in our study was larger generally than the new international reference. Conclusions. The iodine nutritional status in Zhejiang Province was at an adequate level. Despite some limitations in this study, we initially established the reference values for thyroid volume in 8ā10-year-old schoolchildren in Zhejiang Province, China, as a local reference to be used for monitoring iodine deficiency disorders
Nonlinear effects of group size on collective action and resource outcomes.
For decades, scholars have been trying to determine whether small or large groups are more likely to cooperate for collective action and successfully manage common-pool resources. Using data gathered from the Wolong Nature Reserve since 1995, we examined the effects of group size (i.e., number of households monitoring a single forest parcel) on both collective action (forest monitoring) and resource outcomes (changes in forest cover) while controlling for potential confounding factors. Our results demonstrate that group size has nonlinear effects on both collective action and resource outcomes, with intermediate group size contributing the most monitoring effort and leading to the biggest forest cover gain. We also show how opposing effects of group size directly and indirectly affect collective action and resource outcomes, leading to the overall nonlinear relationship. Our findings suggest why previous studies have observed differing and even contradictory group-size effects, and thus help guide further research and governance of the commons. The findings also suggest that it should be possible to improve collective action and resource outcomes by altering factors that lead to the nonlinear group-size effect, including punishing free riding, enhancing overall and within-group enforcement, improving social capital across groups and among group members, and allowing self-selection during the group formation process so members with good social relationships can form groups autonomously. casual inference | commons governance | ecosystem services | biodiversity conservation | sustainability G roups are basic units for collective action and may achieve outcomes that individual efforts cannot (1). However, the threat of free riding implies that the optimal amount of collective action does not always occur, and has led to a substantial literature trying to understand what factors facilitate or block the emergence of collective action. Because collective action is needed to manage many common-pool resources, understanding the mechanisms that shape collective action and resource outcomes is a critical challenge for sustainability (2, 3). From Pareto in 1906 (4) and especially since the influential work by Olson in 1965 (5), group size has been hypothesized as a crucial factor affecting collective action and resource outcomes. (We note that Olson used an unusual definition of "group size": the potential number of group members. Here we follow conventional practice and consider the actual number of participants.) However, the debate on group-size effect continues with some researchers arguing that it is linear and negative (5-7), others arguing for linear and positive (8-11), and still others insisting it is curvilinear (12-14), ambiguous (1, 15-17), or nonsignificant (18-20). Even in the most recent work (8, 15, 19,(21)(22) Previous literature indicates that there are two hypothetical opposing forces through which group size affects collective action and resource outcomes A few previous studies qualitatively described the curvilinear or nonlinear effects of group size (12, 26, 29), and some claimed a nonlinear relationship by simply plotting collective action against group size without controlling other factors (13, 14). However, none has provided a quantitative analysis of field evidence while controlling potential confounding factors, as suggested by Ostrom (7). Furthermore, there is little empirical examination of the mechanisms of nonlinear group-size effects, which is essential to guide commons governance. To fill these knowledge gaps, we used empirical data from our long-term studies (30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44) in Wolong Nature Reserve, Sichuan Province, China (N 30Ā°45ā² -31Ā°25ā², E 102Ā°52ā² -103Ā°24ā²) To understand the group-size effects and the underpinning mechanisms, we combined data on characteristics of households, household groups, and monitored parcels (SI Appendix, Section 1). We acknowledge that conflicts with regard to monitoring might occur within a household, but because the policy is designed to treat households-not individuals-as monitoring units, the common practice of treating households as the unit of analysis is appropriate here. We measured household monitoring efforts by the total amount of labor input (one unit of labor input is defined as one laborer working for 1 d) (SI Appendix, Section 2.1) through surveys. We measured resource outcomes as changes in forest cover derived from previously published forest-cover maps (SI Appendix, Section 1.1.1). We also measured factors that might explain the mechanisms, including free riders (i.e., households that did not participate in monitoring), the level of within-group enforcement (i.e., strong enforcement if there are punishment measures for free-riding members within the group; otherwise, weak enforcement), and within-group division (i.e., whether groups divide into subgroups to conduct monitoring in turns) (SI Appendix, Section 2). Some other contextual factors shown in previous studies to affect group size, collective action, or resource outcomes were used as control variables (SI Appendix, Section 2.3). Results Our results show that group size has a nonlinear effect on the monitoring efforts per household, with an intermediate group size contributing the most Our results demonstrate that group size also has a nonlinear effect on changes in forest cover, with an intermediate group size leading to the biggest gain ( We accounted for as many as possible alternative explanations of the observed nonlinear group-size effects based on systematic quantitative and qualitative analyses. No factor other than group size seems to account for the observed nonlinear effects. First, correlation tests (SI Appendix, Table S2) show that except for the two criteria used for household group assignment (see details in SI Appendix, Section 1.2) by the administrative bureau (i.e., distance between each household and its assigned parcel and received NFCP payment), no other factors were significantly associated with group size and thus are implausible as possible alternative explanations for the group-size effects. We used two additional approaches to ensure that the observed nonlinear effects were not caused by the two criteria used for household group assignments (SI Appendix, Section 2.4.3). We examined the associations between the two criteria used for household group assignment and household monitoring efforts, and we A B Yang et al. PNAS Early Edition | 3 of 6 SUSTAINABILITY SCIENCE estimated two-step Tobit models of monitoring effort. Using either approach, all hypothesized alternatives to group size were linearly associated with household monitoring efforts, and thus could not lead to the observed nonlinear effects. Our path analysis Discussion The coexistence of two opposing forces may also explain why previous studies found different group-size effects. If, as we argue, the net effect of group size is determined by the dynamics (e.g., strength and variation with group size) of the two opposing forces, the optimum point of the net effect (or the necessary range of group size to observe a nonlinear effect) would be dependent on the context (14). The range of group size in our study area may appear to be small. However, the nonlinear pattern we observed means that such a range is large enough to exhibit the nonlinear effect in our context. One of the reasons we find such effects with only moderate variation in group size may be because our study area is a flagship nature reserve for giant pandas. As a result, the local administrative bureau has relatively abundant resources to allocate payments for household groups to monitor parcels and evaluate their performance biannually Unit of analysis is the forest parcel. Dependent variable is the percent of forest-cover change from 2001 to 2007. Additional controls include parcel size, parcel size per household, elevation, distance between each parcel and the nearest household, and distance between each parcel and the main road (SI Appendix, Randomized experiments are sometimes seen as the "gold standard" for research on causal mechanisms. However, there have been no randomized experiments at our site, nor are there likely to be because of its status as a showcase for conservation efforts. In addition, in the real world, there is no randomized or even quasirandomized field experiment in this field of study. The best that can be done in many real-world resource management situations is to be careful with regard to inference. Our analyses show that significant advances in understanding can be made through careful analyses of nonexperimental data by drawing on historical data. Such efforts of ongoing programs provide a useful complement to field experiments in building a cumulative literature and forwarding the important work on collective action and resource management. Our findings also suggest that by regulating factors interacting with group size, it should be possible to improve collective action and resource outcomes. For example, all groups of various sizes can stimulate group members to contribute and protect common-pool resources by punishing free riding and enhancing overall and within-group enforcement. Overall enforcement can be enhanced not only through intensifying costly monitoring efforts but also via improving social capital across groups. The within-group enforcement and outcomes may also be enhanced by improving social capital among group members or allowing self-selection during the group formation process so members with good social relationships can form groups autonomously. Unprecedented deterioration of global commons requires better understandings of the mechanisms shaping collective action and resource outcomes. Because of the complexity of coupled human and natural systems (46), improving such understandings is challenging and requires efforts to integrate data and methods from multiple disciplines. The struggle to understand the groupsize effects is one example showing the importance of such efforts. Our findings help disentangle the puzzle of group-size effects and guide solutions to pressing problems of coupled human and natural systems (47), as well as the design of commons governance policies. Materials and Methods We acquired the map of household monitoring parcels and associated documentation (e.g., the number of households that monitor each forest parcel) from the administrative bureau of Wolong Nature Reserve. To estimate forest-cover change, we used previously published forest-cover maps derived from Landsat imagery in 2001 and 2007 (48, 49). These maps included two main land-cover classes (i.e., forest and nonforest) with overall accuracies between 80% and 88% using independent ground-truth data. Topographic data, such as elevation, slope, and the Compound Topographic Index, a relative measure of wetness (50), were obtained from a digital elevation model at a spatial resolution of 90 m/pixel (51). We measured all household locations (ā¼2,200 households) inside and surrounding the Reserve using Global Positioning System receivers. We calculated geographic metrics of forest parcels and households using the software of ArcGIS 10.1 (ESRI). These metrics include parcel size, parcel size per household, average elevation, average slope, average wetness, distance between each parcel and the nearest household, distance between each parcel and the main road, distance between each household and its monitored parcel, distance between each household and the main road, initial forest cover in 2001, and the percent of forest-cover change from 2001 to 2007. To understand the NFCP planning, implementation, evaluation, and decision-making processes, and to prepare for the household interview, we invited eight Reserve administrative staff for focus group interviews and five officials who were or are in charge of the NFCP for personal interviews. We used best available household survey data containing NFCP implementation information in 2007 and 2009 from our long-term study in the Reserve, which has been tracking ā¼220 randomly sampled households across the years since 1998 (52). The panel survey elicited basic information, such as demographic status, socioeconomic conditions, and energy use (53). In the 2007 and 2009 surveys, besides basic information from panel surveys, we also asked questions regarding NFCP implementation [e.g., NFCP payments, monitoring frequency, time spent for each monitoring, monitoring strategy (e.g., within-group division), and within-group enforcement]. A total of 156 randomly sampled NFCP participating households in 2007, covering the full range of group size (i.e., 1 to 16), were used to examine how group size affects collective action (i.e., household forest monitoring). The 113 households who monitored NFCP parcels with group size larger than one (i.e., 2 to 16) in 2009 were used to examine the mechanisms of nonlinear groupsize effects. We first used a Tobit model to examine the effect of group size on monitoring efforts at the household level. We then used a spatial autoregressive model to examine the effect of group size on forest-cover change at the parcel level. Finally, we conducted the path analysis to test the two hypothetical, opposing forces on the mechanisms of nonlinear group-size effects. Detailed descriptions of data collection, processing, and model specification and construction are provided in SI Appendix. ACKNOWLEDGMENTS
Recombinant Expression and Allergenicity Analysis of Arginine Kinase from Scylla paramamosain
To compare the allergenicity of native arginine kinase (nAK) and recombinant AK (rAK) from Scylla paramamosain and to identify the predominant allergenic domain of AK, AK was divided into 4 fragments: AK-E1 (amino acid (AA) 1ā92), AK-E2 (AA 87ā187), AK-E3 (AA 172ā265), and AK-E4 (AA 276ā357) based on the distribution of epitopes and the spatial structure of the AK molecule. The four recombinant fragments were expressed in the prokaryotic system Escherichia coli, and then nAK, rAK, and the recombinant fragments were purified. The allergenicity of recombinant proteins were evaluated using BALB/c mice. The results showed that the levels of specific antibodies in the serum and the secretion of Th2 type cytokines by the splenocytes of mice sensitized with rAK significantly increased, but the immunogenicity of rAK was weaker than that of nAK. Among the 4 fragments of AK, AK-E2 had the strongest immunogenicity. Meanwhile, rAK could stimulate RBL-2H3 cells to release Ī²-hexokinase, but it was less effective than nAK. Among the 4 expressed fragments, AK-E2 and AK-E4 had a stronger stimulating effect on effector cells. In conclusion, the rAK expressed in the prokaryotic system showed weaker immunogenicity than nAK, and among the 4 fragments of AK, AA 87ā187 has the strongest immunogenicity while AA 276ā357 has the strongest immunoreactivity
(Li0.84Fe0.16)OHFe0.98Se superconductor: Ion-exchange synthesis of large single crystal and highly two-dimensional electron properties
A large and high-quality single crystal (Li0.84Fe0.16)OHFe0.98Se, the optimal
superconductor of newly reported (Li1-xFex)OHFe1-ySe system, has been
successfully synthesized via a hydrothermal ion-exchange technique. The
superconducting transition temperature (Tc) of 42 K is determined by magnetic
susceptibility and electric resistivity measurements, and the zero-temperature
upper critical magnetic fields are evaluated as 79 and 313 Tesla for the field
along the c-axis and the ab-plane, respectively. The ratio of out-of-plane to
in-plane electric resistivity,\r{ho}c/\r{ho}ab, is found to increases with
decreasing temperature and to reach a high value of 2500 at 50 K, with an
evident kink occurring at a characteristic temperature T*=120 K. The negative
in-plane Hall coefficient indicates that electron carriers dominate in the
charge transport, and the hole contribution is significantly reduced as the
temperature is lowered to approach T*. From T* down to Tc, we observe the
linear temperature dependences of the in-plane electric resistivity and the
magnetic susceptibility for the FeSe layers. Our findings thus reveal that the
normal state of (Li0.84Fe0.16)OHFe0.98Se becomes highly two-dimensional and
anomalous prior to the superconducting transition, providing a new insight into
the mechanism of high-Tc superconductivity.Comment: 11 pages, 4 figures, supplementary information is not uploade
Efficacy of Subantimicrobial Dose Doxycycline for Moderate-to-Severe and Active Gravesā Orbitopathy
Aim. To study the efficacy and safety of subantimicrobial dose (SD) doxycycline(50āmg/d) in patients with active and moderate-to-severe Gravesā orbitopathy (GO). Methods. Thirteen patients with active and moderate-to-severe GO received once daily oral doxycycline (50āmg/d) for 12āwk. Treatment response at 24āwk was used as the primary outcome, measured by a composite of improvement in Clinical Activity Score (CAS), diplopia, motility, soft tissue swelling, proptosis, and eyelid aperture. Secondary outcome was the change of quality of life score (QoL, including visual functioning subscale and appearance subscale). Adverse events were also recorded. Results. Overall improvement was noted in eight out of 13 patients (61.5%, 95% CI 31.6%ā86.1%). Both CAS and soft tissue swelling significantly ameliorated in eight patients at 24āwk. Five patients (38.5%) had improvement in ocular motility of ā„8 degrees. Eyelid aperture (46.2%) also decreased remarkably. For QoL, a significant improvement in appearance subscale (P=0.008) was noted during the study, whereas no difference was observed in visual functioning subscale (P=0.21). Two patients reported mild stomachache at 12āwk. Conclusions. SD doxycycline appears to be effective and safe for the treatment of active and moderate-to-severe GO. It might serve as a new promising therapeutic strategy for GO. This trial is registered with NCT01727973
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