Recycling expensive medication: why not?

New (and proposed) advances in packaging, preserving, labeling, and verifying product integrity of individual tablets and capsules may allow for the recycling of certain expensive medicines. Previously sold, but unused, medication, if brought back to special pharmacies for resale or donation, may provide a low-cost source of patent-protected medicines. Benefits of such a program go beyond simply providing affordable medication to the poor. This article suggests that medicine recycling may be a possibility (especially if manufacturers are mandated to blister-package and bar-code individual tablets and capsules). This early discussion of medication recycling identifies relevant issues, such as: need, rationale, existing programs, available supplies, expiration dates, new technology for ensuring safety and potency, environmental impact, public health benefits, program focus, program structure, and liability.     

α-Synuclein Multimers Cluster Synaptic Vesicles and Attenuate Recycling

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Being in a “Green” Building Elicits “Greener” Recycling,but Not Necessarily “Better” Recycling

Previous observational work revealed that transient populations in a sustainable building disposed of waste more accurately when compared to patrons in a non-sustainable building. The current study uses an experimental design to replicate this observed effect and to investigate whether or not the built environment influences motivational factors to impact behavior. We find support that a building designed and built to communicate an atmosphere of sustainability can influence waste disposal behavior. Participants in the sustainable building used the garbage receptacle significantly less and compensated by tending to select the containers and organics receptacle more, which actually resulted in more errors overall. Our findings suggest that building atmospherics can motivate people to recycle more. However, atmospherics alone do not appear to be sufficient to elicit the desired performance outcome.     

Recycling‐mediated facilitation and coexistence based on plant size

We introduce nutrient recycling into a model where competitors differ in the scale at which they perceive their environment. In a two-resource system with both external nutrient inputs and recycling, larger consumers ("integrators") often generate resource distributions that favor their smaller ("nonintegrator") competitors, and vice versa. This occurs because recycling of integrator biomass reduces between-patch resource heterogeneity, whereas recycling of nonintegrator biomass does not. Combined, recycling and throughput can allow coexistence when it is not possible with either alone. With recycling, the presence of an integrator also may facilitate higher biomass of a co-occurring nonintegrator. Our model provides a context where recycling can generate negative feedback between competitors that differ in size and so promote coexistence. This is opposite to the positive recycling-mediated feedback commonly expected on the basis of litter chemistry differences between competitors. Effects of recycling and homogenization on nonintegrators may also be negative in our model, depending on the conformation of the system's resource supply points and the species' relative resource requirements. Our model suggests that the effects of plant size on competitive outcomes may depend critically on the degree of resource recycling found in the system and, reciprocally, that the effects of recycling may depend on plant size.     

Recycling or regulation? The role of amino-terminal modifying enzymes

Post-translational modifications are essential for a variety of functions, such as the translocation, activation, regulation, and, ultimately, degradation of proteins. The amino-terminal (N-terminal) region is a particularly active area for such alterations. Three types of reactions predominate: limited proteolysis to remove one or more amino acids; modification of the alpha-amino group; and side-chain-specific changes. The N-terminal peptidases expose penultimate residues, providing new substrates for peptidase or transferase action. These enzymes can act sequentially or competitively to influence a protein's longevity, location or activity. N-terminal modifying enzymes (NTMEs) might target a protein for ubiquitination and degradation or protect a protein from rapid turnover. The N-terminal peptidases might also have important roles in processing the peptides that are released from the proteasome. Plant NTMEs have roles in senescence, meiosis and defense, and proposed roles in polar auxin transport.     

Stonins—Specialized Adaptors for Synaptic Vesicle Recycling and Beyond?

Stonins are a small family of evolutionarily conserved clathrin adaptor complex AP-2μ-related factors that may act as cargo-specific sorting adaptors in endocytosis and perhaps beyond. Whereas little is known about the localization and function of stonin 1, recent work suggests that stonin 2 serves as a linker between the endocytic proteins AP-2 and Eps15 and the calcium-sensing synaptic vesicle (SV) protein synaptotagmin 1. The molecular determinants involved in the recognition of SV cargo by the μ-homology domain of stonin 2 are evolutionarily conserved from worm to man, thereby identifying stonin 2 and its invertebrate homologs uncoordinated (UNC)-41 and stoned B as endocytic adaptors dedicated to the retrieval of surface-stranded SV proteins, most notably synaptotagmin. In this review, we summarize the current state of knowledge about mammalian stonins with a special focus on the role of stonin 2 in SV recycling at presynaptic nerve terminals.     

Recycling ofd-glucose in collagenous cuticle: A means of nutrient conservation?

Summary Transport by an epithelium, possessing an accumulating, saturable transport system in the apical membrane as well as a finite Fick permeability to the transported solute, was considered in the steady state in the case of zerocis concentration, and in the presence of a peripheral diffusion resistance in a layer apposing thecis face of the tissue (unstirred solution or structural coating). Under suitable conditions, the combination of peripheral diffusion resistance and accumulating epithelial transport may lead to recycling of solute at thecis face of the epithelium. This causes a decrease of the effective permeability to diffusionaltrans-cis flow across the tissue. The phenomenon is discussed in terms of epidermald-glucose transport by the integument of aquatic animals with a collagenous cuticle, such as the seawater-acclimated polychaete wormNereis diversicolor. The recycling phenomenon may be of significance to other epithelia with the function of maintaining large concentration gradients of permeating substances.List of Symbols and Fixed Parameter Values C _m Bulk medium solute concentration,cis face of epidermisC _m=0 mol cm^–3 - C _i Concentration of solute at interface between cuticle and unstirred medium (mol cm^–3) - C _s Concentration of solute atcis face of apical epidermal membrane (mol cm^–3) - C _e Concentration of solute in extracellular fluid,trans-side of epidermisC _e=1.0×10^–6 mol cm^–3 - D _m Diffusion coefficient of solute in outside mediumD _m=6.7×10^–6 cm² sec^–1 - D _c Diffusion coefficient of solute in cuticleD _c=7.4×10^–9 cm² sec^–1 - _m Operative thickness of unstirred medium layer - _c Thickness of cuticle - J Steady-state net flux of solute through cuticle or unstirred layer (flux is positive indirectioncis-trans) (mol cm^–2 sec^–1) - J _i ^max Maximal influx through saturable transport system in apical membraneJ _i ^max =2.0×10^–12 mol cm^–2 sec^–1 - K _t Transport constant, saturable systemK _t=1.0×10^–7 mol cm^–3 - P Epithelial permeability (cm sec^–1)     

α-Synuclein Membrane Association Is Regulated by the Rab3a Recycling Machinery and Presynaptic Activity

α-Synuclein is an abundant presynaptic protein and a primary component of Lewy bodies in Parkinson disease. Although its pathogenic role remains unclear, in healthy nerve terminals α-synuclein undergoes a cycle of membrane binding and dissociation. An α-synuclein binding assay was used to screen for vesicle proteins involved in α-synuclein membrane interactions and showed that antibodies directed to the Ras-related GTPase Rab3a and its chaperone RabGDI abrogated α-synuclein membrane binding. Biochemical analyses, including density gradient sedimentation and co-immunoprecipitation, suggested that α-synuclein interacts with membrane-associated GTP-bound Rab3a but not to cytosolic GDP-Rab3a. Accumulation of membrane-bound α-synuclein was induced by the expression of a GTPase-deficient Rab3a mutant, by a dominant-negative GDP dissociation inhibitor mutant unable to recycle Rab3a off membranes, and by Hsp90 inhibitors, radicicol and geldanamycin, which are known to inhibit Rab3a dissociation from membranes. Thus, all treatments that inhibited Rab3a recycling also increased α-synuclein sequestration on intracellular membranes. Our results suggest that membrane-bound GTP-Rab3a stabilizes α-synuclein on synaptic vesicles and that the GDP dissociation inhibitor·Hsp90 complex that controls Rab3a membrane dissociation also regulates α-synuclein dissociation during synaptic activity.     

α-Taxilin Interacts with Sorting Nexin 4 and Participates in the Recycling Pathway of Transferrin Receptor

Membrane traffic plays a crucial role in delivering proteins and lipids to their intracellular destinations. We previously identified α-taxilin as a binding partner of the syntaxin family, which is involved in intracellular vesicle traffic. α-Taxilin is overexpressed in tumor tissues and interacts with polymerized tubulin, but the precise function of α-taxilin remains unclear. Receptor proteins on the plasma membrane are internalized, delivered to early endosomes and then either sorted to the lysosome for degradation or recycled back to the plasma membrane. In this study, we found that knockdown of α-taxilin induced the lysosomal degradation of transferrin receptor (TfnR), a well-known receptor which is generally recycled back to the plasma membrane after internalization, and impeded the recycling of transferrin. α-Taxilin was immunoprecipitated with sorting nexin 4 (SNX4), which is involved in the recycling of TfnR. Furthermore, knockdown of α-taxilin decreased the number and length of SNX4-positive tubular structures. We report for the first time that α-taxilin interacts with SNX4 and plays a role in the recycling pathway of TfnR.     

Regulation of Integrin β1 Recycling to Lipid Rafts by Rab1a to Promote Cell Migration

Rab1a is a member of the Rab family of small GTPases with a well characterized function in the regulation of vesicle trafficking from the endoplasmic reticulum to the Golgi apparatus and within Golgi compartments. The integrin family heterodimeric transmembrane proteins serve as major receptors for extracellular matrix proteins, which play essential roles in cell adhesion and migration. Although effects on intracellular trafficking of integrins or other key cargos by Rab1a could influence cell migration, the regulatory mechanisms linking Rab1a to cell migration are not well understood. Here, we report identification of Rab1a as a novel regulator of cell migration using an unbiased RNAi screen targeting GTPases. Inhibition of Rab1a reduced integrin-mediated cell adhesion and spreading on fibronectins, reduced integrin β1 localization to lipid rafts, and decreased recycling of integrin β1 to the plasma membrane. Analysis of Rab1a effector molecules showed that p115 mediated Rab1a regulation of integrin recycling and lipid raft localization in cell migration. Taken together, these results suggest a novel function for Rab1a in the regulation of cell migration through controlling integrin β1 recycling and localization to lipid rafts via a specific downstream effector pathway.     

Preliminary Evaluation of a White-Rot Fungal Reactor in the Treatment of a Waste Oil–Recycling Wastewater

An investigation of the treatment of a complex waste oil–recycling hydrocarbon wastewater was made by employing white-rot fungal strains immobilized in a pinewood chip-packed reactor. The reactor was operated in sequencing batch mode. The fungal reactor was evaluated in a preliminary bench-scale reactor followed by intermediate-scale operation. Substantial chemical oxygen demand (COD) reduction (> 96% in 48-h batch cycles) and removal of specific influent compound constituents, alkanes (n-C8, n-C10–C12) and aromatic compound (o-xylene), was shown in diluted and undiluted (COD > 37 g L^?1) influent. Industrial application of the fungal reactor was evaluated in a 14-m³ pilot plant erected on-site at a waste oil–processing facility. The scale-up implication and optimization of the field plant is discussed in relation to the process-monitoring programme.     

Activation of Protein Kinase C α Is Necessary for Sorting the PDGF β-Receptor to Rab4a-dependent Recycling

Previous studies showed that loss of the T-cell protein tyrosine phosphatase (TC-PTP) induces Rab4a-dependent recycling of the platelet-derived growth factor (PDGF) β-receptor in mouse embryonic fibroblasts (MEFs). Here we identify protein kinase C (PKC) α as the critical signaling component that regulates the sorting of the PDGF β-receptor at the early endosomes. Down-regulation of PKC abrogated receptor recycling by preventing the sorting of the activated receptor into EGFP-Rab4a positive domains on the early endosomes. This effect was mimicked by inhibition of PKCα, using myristoylated inhibitory peptides or by knockdown of PKCα with shRNAi. In wt MEFs, short-term preactivation of PKC by PMA caused a ligand-induced PDGF β-receptor recycling that was dependent on Rab4a function. Together, these observations demonstrate that PKC activity is necessary for recycling of ligand-stimulated PDGF β-receptor to occur. The sorting also required Rab4a function as it was prevented by expression of EGFP-Rab4aS22N. Preventing receptor sorting into recycling endosomes increased the rate of receptor degradation, indicating that the sorting of activated receptors at early endosomes directly regulates the duration of receptor signaling. Activation of PKC through the LPA receptor also induced PDGF β-receptor recycling and potentiated the chemotactic response to PDGF-BB. Taken together, our present findings indicate that sorting of PDGF β-receptors on early endosomes is regulated by sequential activation of PKCα and Rab4a and that this sorting step could constitute a point of cross-talk with other receptors.     

The Cell Wall of the Arabidopsis Pollen Tube��Spatial Distribution, Recycling, and Network Formation of Polysaccharides

The pollen tube is a cellular protuberance formed by the pollen grain, or male gametophyte, in flowering plants. Its principal metabolic activity is the synthesis and assembly of cell wall material, which must be precisely coordinated to sustain the characteristic rapid growth rate and to ensure geometrically correct and efficient cellular morphogenesis. Unlike other model species, the cell wall of the Arabidopsis (Arabidopsis thaliana) pollen tube has not been described in detail. We used immunohistochemistry and quantitative image analysis to provide a detailed profile of the spatial distribution of the major cell wall polymers composing the Arabidopsis pollen tube cell wall. Comparison with predictions made by a mechanical model for pollen tube growth revealed the importance of pectin deesterification in determining the cell diameter. Scanning electron microscopy demonstrated that cellulose microfibrils are oriented in near longitudinal orientation in the Arabidopsis pollen tube cell wall, consistent with a linear arrangement of cellulose synthase CESA6 in the plasma membrane. The cellulose label was also found inside cytoplasmic vesicles and might originate from an early activation of cellulose synthases prior to their insertion into the plasma membrane or from recycling of short cellulose polymers by endocytosis. A series of strategic enzymatic treatments also suggests that pectins, cellulose, and callose are highly cross linked to each other.Upon contact with the stigma, the pollen grain swells through water uptake and develops a cellular protrusion, the pollen tube. During its growth in planta, the pollen tube invades the transmitting tissue of the pistil and finds its way to the ovary to deliver the male gametes for double fertilization to happen (Heslop-Harrison, 1987). Depending on the species, pollen tubes can grow extremely rapidly both in planta and in in vitro conditions. To fulfill its biological function, the pollen tube has to (1) adhere to and invade transmitting tissues (Hill and Lord, 1987; Lennon et al., 1998), (2) provide physical protection to the sperm cells, and (3) control its own shape and invasive behavior (Parre and Geitmann, 2005b; Geitmann and Steer, 2006). For all of these functions, the pollen tube cell wall plays an important regulatory and structural role. Although the pollen tube does not form a conventional secondary cell wall layer, its wall is assembled in two phases. The “primary layer” is mainly formed of pectins and other matrix components secreted at the apical end of the cell. The “secondary layer” is assembled by the deposition of callose in more distal regions of the cell (Heslop-Harrison, 1987). Depending on the species, cellulose microfibrils have been found to be associated either with the outer pectic or with the inner callosic layer. Unlike most other plant cells, cellulose is not very abundant representing only 10% of total neutral polysaccharides in Nicotiana alata pollen tubes, whereas callose accounts for more than 80% in this species (Schlüpmann et al., 1994).The biochemical composition of the pollen tube cell wall has been well characterized in many species such as Lilium longiflorum (Lancelle and Hepler, 1992; Jauh and Lord, 1996), tobacco (Nicotiana tabacum; Kroh and Knuiman, 1982; Geitmann et al., 1995; Ferguson et al., 1998; Derksen et al., 2011), Petunia hybrida (Derksen et al., 1999), Pinus sylvestris (Derksen et al., 1999), and Solanum chacoense (Parre and Geitmann, 2005a). But for Arabidopsis (Arabidopsis thaliana), the model for plant molecular biology studies (Arabidopsis Genome Initiative, 2000), there is a striking lack of quantitative information concerning the composition of the pollen tube cell wall as well as the spatial distribution of its components. This is all the more surprising because numerous mutants defective in enzymes involved in cell wall synthesis exhibit a pollen tube phenotype (for example, Jiang et al., 2005; Nishikawa et al., 2005; Wang et al., 2011). Two studies have characterized the Arabidopsis pollen germinating in vitro (Derksen et al., 2002) and in vivo (Lennon and Lord, 2000), but both are qualitative rather than quantitative. A biochemical study by Dardelle and coworkers investigated the cell wall sugar composition in a more quantitative way but does not provide any detailed spatial information (Dardelle et al., 2010; Lehner et al., 2010). This lack of information is not surprising given that until recently Arabidopsis pollen was known to be rather challenging to germinate reproducibly in vitro and more difficult to manipulate than the pollen of many other plant species (Bou Daher et al., 2009). With the publication of optimized methods for in vitro germination (Boavida and McCormick, 2007; Bou Daher et al., 2009), it has become much more feasible to germinate healthy-looking Arabidopsis pollen tubes in vitro in a highly reproducible way.The precisely controlled spatial distribution of biochemical components in the pollen tube cell wall is crucial for shape generation and maintenance of this perfectly cylindrical cell (Geitmann and Parre, 2004; Aouar et al., 2010; Fayant et al., 2010; Geitmann, 2010). The pollen tube, therefore, represents an ideal model system to study the link between intracellular signaling, biochemistry, cell mechanical properties, and morphogenesis in plant cells. Because of its typically fast growth rates, it responds quickly to any environmental triggers such as pharmacological, hormone, or enzymatic treatments. Adding Arabidopsis to the group of commonly studied pollen tube species is particularly timely, because one-third of the approximately 800 cell wall synthesis genes identified in this species are expressed in or are specific to its pollen (Pina et al., 2005). Therefore, the Arabidopsis pollen tube has become a valuable system for cell wall studies, especially with the increasing availability of cell wall mutant lines (Liepman et al., 2010).Here we describe the biochemical composition of the Arabidopsis pollen tube cell wall grown in in vitro conditions using immunocytochemical labeling coupled with epifluorescence and electron microscopic techniques. Rather than relying on imaging alone, we developed a quantitative strategy to assess the precise spatial distribution of cell wall components. This quantitative approach will provide an important tool and baseline dataset for the investigation of mutant phenotypes and for the interpretation of pharmacological studies. Furthermore, we used selective and strategically combined enzymatic digestions to determine the degree of connectivity between the individual types of cell wall polysaccharide networks.     

PKD Controls αvβ3 Integrin Recycling and Tumor Cell Invasive Migration through Its Substrate Rabaptin-5

Integrin recycling is critical for cell migration. Protein kinase D (PKD) mediates signals from the platelet-derived growth factor receptor (PDGF-R) to control αvβ3 integrin recycling. We now show that Rabaptin-5, a Rab5 effector in endosomal membrane fusion, is a PKD substrate. PKD phosphorylates Rabaptin-5 at Ser407, and this is both necessary and sufficient for PDGF-dependent short-loop recycling of αvβ3, which in turn inhibits α5β1 integrin recycling. Rab4, but not Rab5, interacts with phosphorylated Rabaptin-5 toward the front of migrating cells to promote delivery of αvβ3 to the leading edge, thereby driving persistent cell motility and invasion that is dependent on this integrin. Consistently, disruption of Rabaptin-5 Ser407 phosphorylation reduces persistent cell migration in 2D and αvβ3-dependent invasion. Conversely, invasive migration that is dependent on α5β1 integrin is promoted by disrupting Rabaptin phosphorylation. These findings demonstrate that the PKD pathway couples receptor tyrosine kinase signaling to an integrin switch via Rabaptin-5 phosphorylation.     

It's Déjà Vu All Over Again: The Intelligent Design Movement's Recycling of Creationist Strategies

The intelligent design (ID) creationist movement is now a quarter of a century old. ID proponents at the Discovery Institute, headquartered in Seattle, WA, USA, insist that ID is not creationism. However, it is the direct descendant of the creation science movement that began in the 1960s and continued until the definitive ruling against creationism by the US Supreme Court in Edwards v. Aguillard 1987, which struck down laws that required balancing the teaching of evolution with creationism in public schools. Already anticipating in the early 1980s that Arkansas and Louisiana “balanced treatment” laws would be declared unconstitutional, a group of creationists led by Charles Thaxton began laying the groundwork for what is now the ID movement. After Edwards, Thaxton and his associates promoted ID aggressively until it, too, was declared unconstitutional by a federal judge in Kitzmiller et al. v. Dover Area School District 2005. Subsequently, in 2008, the Discovery Institute began its multistate promotion of model “academic freedom” legislation that bears striking parallels to the 1980s balanced treatment laws. Because of Kitzmiller, ID proponents have written their model legislation in code language in an effort to avoid another court challenge. Yet despite attempting to evade the legal constraints imposed by Edwards, they are merely recycling earlier creationist tactics that date back to the late 1970s and early 1980s. The tactics that ID creationists now use—promoting legislation, publishing “educational” materials, establishing a “research” institute, and sanitizing their terminology—are the recycled tactics of their creation science predecessors.     

β1-Adrenergic Receptor Recycles Via a Membranous Organelle, Recycling Endosome, by Binding with Sorting Nexin27

In cardiomyocytes, β₁-adrenergic receptor (β₁-AR) plays an important role in regulating cardiac functions. Upon continuous ligand stimulation, β₁-AR is internalized and mostly recycled back to the plasma membrane (PM). The recycling endosome (RE) is one of the membranous organelles involved in the protein recycling pathway. To determine whether RE is involved in the internalization of β₁-AR upon ligand stimulation, we evaluated the localization of β₁-AR after stimulation with a β-agonist, isoproterenol (Iso), in β₁-AR-transfected COS-1 cells. After 30 min of Iso treatment and cell surface labeling with the appropriate antibodies, β₁-AR was internalized from PM and translocated into the perinuclear region, the same location as the transferrin receptor, an RE marker. We then evaluated whether sorting nexin 27 (SNX27) participated in the β₁-AR recycling pathway. When β₁-AR and SNX27 were coexpressed, β₁-AR coimmunoprecipitated with SNX27. In addition, shRNA-mediated silencing of SNX27 compromised β₁-AR recycling and enhanced its delivery into lysosome. Overall, β₁-AR on PM was internalized into RE upon Iso stimulation and recycled by RE through binding with SNX27 in COS-1 cells.     

Phosphatidylinositol 3,4,5-trisphosphate Localization in Recycling Endosomes Is Necessary for AP-1B–dependent Sorting in Polarized Epithelial Cells

Polarized epithelial cells coexpress two almost identical AP-1 clathrin adaptor complexes: the ubiquitously expressed AP-1A and the epithelial cell–specific AP-1B. The only difference between the two complexes is the incorporation of the respective medium subunits μ1A or μ1B, which are responsible for the different functions of AP-1A and AP-1B in TGN to endosome or endosome to basolateral membrane targeting, respectively. Here we demonstrate that the C-terminus of μ1B is important for AP-1B recruitment onto recycling endosomes. We define a patch of three amino acid residues in μ1B that are necessary for recruitment of AP-1B onto recycling endosomes containing phosphatidylinositol 3,4,5-trisphosphate [PI(3,4,5)P₃]. We found this lipid enriched in recycling endosomes of epithelial cells only when AP-1B is expressed. Interfering with PI(3,4,5)P₃ formation leads to displacement of AP-1B from recycling endosomes and missorting of AP-1B–dependent cargo to the apical plasma membrane. In conclusion, PI(3,4,5)P₃ formation in recycling endosomes is essential for AP-1B function.