RESUMEN
Restoration of degraded drylands is urgently needed to mitigate climate change, reverse desertification and secure livelihoods for the two billion people who live in these areas. Bold global targets have been set for dryland restoration to restore millions of hectares of degraded land. These targets have been questioned as overly ambitious, but without a global evaluation of successes and failures it is impossible to gauge feasibility. Here we examine restoration seeding outcomes across 174 sites on six continents, encompassing 594,065 observations of 671 plant species. Our findings suggest reasons for optimism. Seeding had a positive impact on species presence: in almost a third of all treatments, 100% of species seeded were growing at first monitoring. However, dryland restoration is risky: 17% of projects failed, with no establishment of any seeded species, and consistent declines were found in seeded species as projects matured. Across projects, higher seeding rates and larger seed sizes resulted in a greater probability of recruitment, with further influences on species success including site aridity, taxonomic identity and species life form. Our findings suggest that investigations examining these predictive factors will yield more effective and informed restoration decision-making.
Asunto(s)
Ecosistema , Plantones , Cambio Climático , Humanos , Plantas , SemillasRESUMEN
A small library of amino acid ester prodrugs of 6-ß-naltrexol (NTXOL, 1) was prepared in order to investigate the candidacy of these prodrugs for microneedle-enhanced transdermal delivery. Six amino acid ester prodrugs were synthesized (6a-f). 6b, 6d, and 6 e were stable enough at skin pH (pH 5.0) to move forward to studies in 50% human plasma. The lead compound (6 e) exhibited the most rapid bioconversion to NTXOL in human plasma (t1/2 = 2.2 ± 0.1h).
Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Naltrexona/análogos & derivados , Profármacos/administración & dosificación , Profármacos/síntesis química , Administración Cutánea , Aminoácidos/administración & dosificación , Aminoácidos/síntesis química , Estabilidad de Medicamentos , Humanos , Naltrexona/administración & dosificación , Naltrexona/síntesis química , Agujas , Absorción Cutánea/efectos de los fármacos , Absorción Cutánea/fisiologíaRESUMEN
The purpose of these studies was to determine if a Büchi Mini Spray Dryer B-290 (Büchi Corporation, New Castle, DE, USA) could be used to prepare blackberry extract powders containing mannitol as a thermoprotectant without extensively degrading anthocyanins and polyphenols in the resulting powders. Three blackberry puree extract samples were each prepared by sonication of puree in 30/70% ethanol/water containing 0.003% HCl. Blackberry puree extract sample 1 (S1) contained no mannitol, while blackberry puree extract sample 2 (S2) contained 3.0:1 (w/w) mannitol:berry extract, and blackberry puree extract sample 3 (S3) contained 6.3:1 (w/w) mannitol:berry extract. The levels of anthocyanins and polyphenols in reconstituted spray-dried powders produced from S1-S3 were compared to solutions of S1-S3 that were held at 4°C as controls. All extract samples could be spray-dried using the Büchi Mini Spray Dryer B-290. S1, with no mannitol, showed a 30.8% decrease in anthocyanins and a 24.1% decrease in polyphenols following spray-drying. However, S2 had a reduction in anthocyanins of only 13.8%, while polyphenols were reduced by only 6.1%. S3, with a ratio of mannitol to berry extract of 6.3:1, exhibited a 12.5% decrease in anthocyanins while the decrease in polyphenols after spray-drying was not statistically significant (P=.16). Collectively, these data indicate that a Büchi Mini Spray Dryer B-290 is a suitable platform for producing stable berry extract powders, and that mannitol is a suitable thermoprotectant that facilitates retention of thermosensitive polyphenolic species in berry extracts during spray-drying.
Asunto(s)
Manitol/química , Extractos Vegetales/química , Polifenoles/química , Conservadores Farmacéuticos/química , Rubus/química , Desecación , Estabilidad de Medicamentos , Frutas/química , Calor , Polvos/químicaRESUMEN
In the title compound, C(22)H(20)N(+)·I(-), the dihedral angles between the central pyridine ring and two outer benzene rings are 15.30â (10) and 11.82â (11)°. There are inter-molecular π-π stacking inter-actions between the nearest phenyl ring over an inversion-related pyridyl ring, the shortest centroid-centroid distance being 3.672â (3)â Å. The crystal structure of the compound indicates the 2,6-distyryl substituents have an E configuration.
RESUMEN
The pre-administration of dexamethasone (DEX) has previously been shown to enhance the anti-tumor efficacy of chemotherapeutic agents. The delivery of anti-inflammatory agents specifically to tumors via nanoparticle carriers is expected to promote the effectiveness of chemotherapeutic agents while avoiding systemic toxicities. The process for preparing solid lipid nanoparticles containing anti-inflammatory agents using the nanotemplate engineering method was optimized. Due to the solubilization of DEX in the bulk aqueous phase, its more lipophilic palmitate ester was synthesized and incorporated in nanoparticles that included a pegylating agent, PEG6000 mono-stearate, as part of the formulation. The stealth properties of these nanoparticles were demonstrated to be enhanced compared to latex particles by measuring the adsorption of radioiodinated IgG (185 microg vs. 6.7 microg IgG/mg NP). In addition, the uptake of (14)C-labeled nanoparticles by murine macrophages was shown to decrease from 36.6% to 14.7% of the nanoparticles/mg cell protein as the amount of pegylating agent in the formulation increased from 0 to 4 mg/mL. The high loading values and low burst effect observed for these DEX palmitate-containing nanoparticles in addition to their stealth properties are expected to allow for the delivery of sufficient amounts of DEX to tumors to enhance the uptake of chemotherapeutic agents.