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1.
Ecological restoration is considered to play an important role in mitigating climate change, protecting biodiversity, and preventing environmental degradation. Yet, there are often multiple perspectives on what outcomes restoration should be aiming to achieve, and how we should get to that point. In this study we interview a range of policymakers, academics, and non‐governmental organization (NGO) representatives to explore the range of perspectives on the restoration of Indonesia's tropical peatlands—key global ecosystems that have undergone large‐scale degradation. Thematic analysis suggests that participants agreed about the importance of restoration, but had differing opinions on how effective restoration activities to date have been and what a restored peatland landscape should look like. These results exemplify how ecological restoration can mean different things to different people, but also highlight important areas of consensus for moving forward with peatland restoration strategies.  相似文献   
2.
High-throughput purification of affinity-tagged fusion proteins is currently one of the fastest developing areas of molecular proteomics. A prerequisite for success in protein purification is sufficient soluble protein expression of the target protein in a heterologous host. Hence, a fast and quantitative evaluation of the soluble-protein levels in an expression system is one of the key steps in the entire process. Here we describe a high-throughput expression screen for affinity-tagged fusion proteins based on an enzyme linked immunofiltration assay (ELIFA). An aliquot of a crude Escherichia coli extract containing the analyte, an affinity-tagged protein, is adsorbed onto the membrane. Subsequent binding of specific antibodies followed by binding of a secondary antibody horseradish peroxidase (HRP) complex then allows quantitative evaluation of the analyte using tetramethylbenzidine as the substrate for HRP. The method is accurate and quantitative, as shown by comparison with results from western blotting and an enzymatic glutathione S-transferase (GST) assay. Furthermore, it is a far more rapid assay and less cumbersome than western blotting, lending itself more readily to high-throughput analysis. It can be used at the expression level (cell lysates) or during the subsequent purification steps to monitor yield of specific protein.  相似文献   
3.
Abnormal polyglutamine (polyQ) tracts are the only common feature in nine proteins that each cause a dominant neurodegenerative disorder. In Huntington's disease, tracts longer than 36 glutamines in the protein huntingtin (htt) cause degeneration. In situ, monoclonal antibody 3B5H10 binds to different htt fragments in neurons in proportion to their toxicity. Here, we determined the structure of 3B5H10 Fab to 1.9?? resolution by X-ray crystallography. Modeling demonstrates that the paratope forms a groove suitable for binding two β-rich polyQ strands. Using small-angle X-ray scattering, we confirmed that the polyQ epitope recognized by 3B5H10 is a compact two-stranded hairpin within monomeric htt and is abundant in htt fragments unbound to antibody. Thus, disease-associated polyQ stretches preferentially adopt compact conformations. Since 3B5H10 binding predicts degeneration, this compact polyQ structure may be neurotoxic.  相似文献   
4.
Magnetic macroporous PGMA and PHEMA microspheres containing carboxyl groups are synthesized by multi-step swelling and polymerization followed by precipitation of iron oxide inside the pores. The microspheres are characterized by SEM, IR spectroscopy, AAS, and zeta-potential measurements. Their functional groups enable bioactive ligands of various sizes and chemical structures to couple covalently. The applicability of these monodisperse magnetic microspheres in biospecific catalysis and bioaffinity separation is confirmed by coupling with the enzyme trypsin and huIgG. Trypsin-modified magnetic PGMA-COOH and PHEMA-COOH microspheres are investigated in terms of their enzyme activity, operational and storage stability. The presence of IgG molecules on microspheres is confirmed.  相似文献   
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Commercially used natural rubber (cis-1,4-polyisoprene) is a secondary metabolite of the rubber tree (Hevea brasiliensis). Previous studies have shown the involvement of a prenyl transferase in the final steps of natural rubber biosynthesis which includes polymerization of isopentenyl pyrophosphate into rubber. Using synthetic oligonucleotides corresponding to the partial amino acid sequences of this protein as probes to screen a laticifer-specific cDNA library, we have isolated a full-length cDNA which encodes a 47 kDa protein with strong homology to farnesyl diphosphate synthases from many species. The catalytic activity of this protein was confirmed by complementing the deletion yeast mutant. In Hevea, this gene is expressed in latex producing cells and in the epidermal region of the rubber plant suggesting a dual role for the protein in the biosyntheses of rubber and other isoprenoids. Although the expression level of this gene is not significantly affected by hormone treatment (e.g. ethylene), regeneration of latex due to tapping increases its expression level.  相似文献   
7.
Gliomas are the most common form of malignant primary brain tumors in humans and second most common in dogs, occurring with similar frequencies in both species. Dogs are valuable spontaneous models of human complex diseases including cancers and may provide insight into disease susceptibility and oncogenesis. Several brachycephalic breeds such as Boxer, Bulldog and Boston Terrier have an elevated risk of developing glioma, but others, including Pug and Pekingese, are not at higher risk. To identify glioma-associated genetic susceptibility factors, an across-breed genome-wide association study (GWAS) was performed on 39 dog glioma cases and 141 controls from 25 dog breeds, identifying a genome-wide significant locus on canine chromosome (CFA) 26 (p = 2.8 x 10−8). Targeted re-sequencing of the 3.4 Mb candidate region was performed, followed by genotyping of the 56 SNVs that best fit the association pattern between the re-sequenced cases and controls. We identified three candidate genes that were highly associated with glioma susceptibility: CAMKK2, P2RX7 and DENR. CAMKK2 showed reduced expression in both canine and human brain tumors, and a non-synonymous variant in P2RX7, previously demonstrated to have a 50% decrease in receptor function, was also associated with disease. Thus, one or more of these genes appear to affect glioma susceptibility.  相似文献   
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9.

Introduction

Health and development organizations increasingly promote livelihood interventions to improve health and economic outcomes for people living with HIV (PLHIV) receiving treatment with antiretroviral therapy (ART). In-depth understanding about how PLHIV make labor decisions in the context of treatment for HIV – and treatment decisions in the context of their livelihoods – is essential to guiding intervention design and developing hypotheses for future research on livelihoods and ART. However, few studies have explored the perspectives of PLHIV regarding integration of livelihoods and ART in urban, resource-limited settings.

Methods

Qualitative interviews explored the livelihood experiences of food insecure ART patients in four Bolivian cities (n = 211). Topics included work-related barriers to ART adherence, HIV-related barriers to work, and economic coping mechanisms. Themes were identified using content coding procedures, with two coders to maximize reliability.

Results

Participants reported complex economic lives often characterized by multiple economic activities, including both formal and informal labor. They struggled to manage ART treatment and livelihoods simultaneously, and faced a range of interpersonal and structural barriers. In particular, lack of HIV status disclosure, stigma, and discrimination were highly salient issues for study participants and likely to be unique to people with HIV, leading to conflict around requesting time off for clinic visits, resentment from co-workers about time off, and difficulties adhering to medication schedules. In addition, health system issues such as limited clinic hours or drug shortages exacerbated the struggle to balance economic activities with HIV treatment adherence.

Conclusions

Improved policy-level efforts to enforce existing anti-discrimination laws, reduce HIV-related stigma, and expand health services accessibility could mitigate many of the barriers discussed by our participants, improve adherence, and reduce the need for livelihoods interventions.  相似文献   
10.
Magnetic minerals, such as magnetite and hematite, have been reported to be present, in particular, leaves as biogenic particles. The magnetic minerals and properties of Ni hyperaccumulators have not previously been reported in the literature. This study aimed to characterize the magnetic properties of two Ni hyperaccumulating plant species, R. bengalensis and P. oxyhedra, which grow in an ultramafic region on Halmahera Island, Indonesia. For comparison, similar characterization was carried out on two non-hyperaccumulating plant species which grow in the same region. Concentrations of Ni, Fe, and Mn in the leaves of the hyperaccumulating plants were measured using atomic absorption spectroscopy (AAS) and their magnetic properties were characterized using measurements of magnetic susceptibility, low temperature magnetic susceptibility, and hysteresis curves. The results show that, compared to the non-hyperaccumulating plants, the Ni hyperaccumulating plants have higher concentrations of Ni and similar concentration of Fe. The magnetic susceptibilities of hyperaccumulating plants are positive, and those of non-hyperaccumulating plants are negative. This suggests that the abundance of Ni, rather than Fe, may control the magnetic properties of Ni hyperaccumulating plants. This probable connection between Ni concentration and plant magnetic properties could be advantageous for identifying hyperaccumulators, and should, therefore, be explored further.  相似文献   
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