Orange IV stabilizes silk fibroin microemulsions

Silk fibroin (SF) is a natural biopolymer that has been extensively studied in various applications due to its impressive mechanical properties and biocompatibility. Recently, SF-based particles have been proposed as controlled drug delivery systems. A new and efficient method to prepare SF microemulsions (SF-MEs) was developed by oil-in-water emulsions using high-pressure homogenization to promote emulsification. During SF-ME production, the secondary structure of SF changed to a more stable conformation (from random coil to -sheets), thus allowing the formation of small and stable (140.7 ± 1.9 nm; polydispersity index, 0.25) SF microparticles (SF-MPs). The efficiency of SF-MP formation was 60%. Orange IV was used as a model compound for incorporation and release studies, although its incorporation into the SF-MEs significantly improved particle size and size distribution over at least 4 wk compared to traditional stabilizers (e.g., poloxamer 407, transcutol, Tween 80, and SDS). This should be a call of attention when using dyes as model compounds since they can influence particle properties and lead to misinterpretation of the results. Orange IV showed an incorporation efficiency of 91% and a controlled release over time. Stable SF-MP formulations, further enhanced by orange IV incorporation, provide an innovative method with potential application in pharmaceutical development due to its associated high biocompatibility and release profile.The authors thank the FCT Strategic Project PEst-OE/EQB/LA0023/2013 and the project "BioHealth - Biotechnology and Bioengineering Approaches to Improve Health Quality," Ref. NORTE-07-0124-FEDER-000027, cofunded by the Programa Operacional Regional do Norte (ON.2 - O Novo Norte), QREN, FEDER. We would also like to acknowledge CRA - Unita di Ricerca di Apicoltura and Bachicoltura Padova (Italy) for the supply of B. mori silkworm cocoons, and Andreia Vasconcelos for technical support

Mutations in PNPLA6 are linked to photoreceptor degeneration and various forms of childhood blindness

Blindness due to retinal degeneration affects millions of people worldwide, but many disease-causing mutations remain unknown. PNPLA6 encodes the patatin-like phospholipase domain containing protein 6, also known as neuropathy target esterase (NTE), which is the target of toxic organophosphates that induce human paralysis due to severe axonopathy of large neurons. Mutations in PNPLA6 also cause human spastic paraplegia characterized by motor neuron degeneration. Here we identify PNPLA6 mutations in childhood blindness in seven families with retinal degeneration, including Leber congenital amaurosis and Oliver McFarlane syndrome. PNPLA6 localizes mostly at the inner segment plasma membrane in photo-receptors and mutations in Drosophila PNPLA6 lead to photoreceptor cell death. We also report that lysophosphatidylcholine and lysophosphatidic acid levels are elevated in mutant Drosophila. These findings show a role for PNPLA6 in photoreceptor survival and identify phospholipid metabolism as a potential therapeutic target for some forms of blindness.Foundation Fighting Blindness CanadaCanadian Institutes of Health ResearchNIHCharles University institutional programmesBIOCEV-Biotechnology and Biomedicine Centre of the Academy of Sciences and Charles University, from the European Regional Development FundMinistry of Health of the Czech RepublicGraduate School of Life Sciences (University of Wuerzburg)Government of Canada through Genome CanadaOntario Genomics InstituteGenome QuebecGenome British ColumbiaMcLaughlin CentreCharles Univ Prague, Inst Inherited Metab Disorders, Fac Med 1, Prague 12000 2, Czech RepublicMcGill Univ, Dept Human Genet, Fac Med, Montreal, PQ H3A 0G1, CanadaGenome Quebec Innovat Ctr, Montreal, PQ H3A 0G1, CanadaClin Res Inst Montreal, Cellular Neurobiol Res Unit, Montreal, PQ H2W 1R7, CanadaMcGill Univ, Montreal, PQ H3A 0G4, CanadaMcGill Univ, Ctr Hlth, Montreal Childrens Hosp, McGill Ocular Genet Lab, Montreal, PQ H3H 1P3, CanadaMcGill Univ, Ctr Hlth, Montreal Childrens Hosp, Dept Paediat Surg, Montreal, PQ H3H 1P3, CanadaMcGill Univ, Ctr Hlth, Montreal Childrens Hosp, Dept Human Genet, Montreal, PQ H3H 1P3, CanadaMcGill Univ, Ctr Hlth, Montreal Childrens Hosp, Dept Ophthalmol, Montreal, PQ H3H 1P3, CanadaUniv Alberta, Royal Alexandra Hosp, Dept Ophthalmol & Visual Sci, Edmonton, AB T5H 3V9, CanadaCharles Univ Prague, Inst Biol & Med Genet, Fac Med 1, Prague 12000 2, Czech RepublicBaylor Coll Med, Dept Mol & Human Genet, Human Genome Sequencing Ctr, Houston, TX 77030 USAUniversidade Federal de São Paulo, Dept Neurol, Div Gen Neurol, BR-04021001 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Neurol, Ataxia Unit, BR-04021001 São Paulo, BrazilNewcastle Univ, Inst Med Genet, Newcastle Upon Tyne NE1 3BZ, Tyne & Wear, EnglandUniversidade Federal de São Paulo, Dept Ophthalmol, BR-04021001 São Paulo, BrazilSo Gen Hosp, Dept Clin Genet, Glasgow G51 4TF, Lanark, ScotlandCardiff Univ, Sch Med, Inst Med Genet, Cardiff CF14 4XN, S Glam, WalesHadassah Hebrew Univ Med Ctr, Dept Ophthalmol, IL-91120 Jerusalem, IsraelOregon Hlth & Sci Univ, Oregon Inst Occupat Hlth Sci, Portland, OR 97239 USAUniv Wurzburg, Lehrstuhl Neurobiol & Genet, D-97074 Wurzburg, GermanyUniv Montreal, Dept Med, Montreal, PQ H3T 1P1, CanadaMcGill Univ, Dept Anat & Cell Biol, Div Expt Med, Montreal, PQ H3A 2B2, CanadaUniversidade Federal de São Paulo, Dept Neurol, Div Gen Neurol, BR-04021001 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Neurol, Ataxia Unit, BR-04021001 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Ophthalmol, BR-04021001 São Paulo, BrazilNIH: EY022356-01NIH: EY018571-05NIH: NS047663-09Charles University institutional programmes: PRVOUK-P24/LF1/3Charles University institutional programmes: UNCE 204011Charles University institutional programmes: SVV2013/266504BIOCEV-Biotechnology and Biomedicine Centre of the Academy of Sciences and Charles University, from the European Regional Development Fund: CZ.1.05/1.1.00/02.0109Ministry of Health of the Czech Republic: NT13116-4/2012Ministry of Health of the Czech Republic: NT14015-3/2013Ontario Genomics Institute: OGI-049Web of Scienc

The difference that ‘one drop’ makes: Mexican and African Americans, mixedness and racial categorisation in the early twentieth century

Using archival materials, I will examine how the mixed ancestry of African and Mexican Americans was treated, both in law and discourse, in distinctly contrasting ways in the early 20th century. I will argue that black and Mexican subjects were positioned in qualitatively different ways in relation to whiteness. Furthermore, the singular treatment of ‘black blood’ as a social toxin, a construction emerging within the specific circumstances of American slavery, also informed the subjective positioning of Mexicans, as well as shaping some Mexican Americans’ responses to racism

Fly cryptochrome and the visual system

Cryptochromes are flavoproteins, structurally and evolutionarily related to photolyases, that are involved in the development, magnetoreception, and temporal organization of a variety of organisms. Drosophila CRYPTOCHROME (dCRY) is involved in light synchronization of the master circadian clock, and its C terminus plays an important role in modulating light sensitivity and activity of the protein. The activation of dCRY by light requires a conformational change, but it has been suggested that activation could be mediated also by specific "regulators" that bind the C terminus of the protein. This C-terminal region harbors several protein-protein interaction motifs, likely relevant for signal transduction regulation. Here, we show that some functional linear motifs are evolutionarily conserved in the C terminus of cryptochromes and that class III PDZ-binding sites are selectively maintained in animals. A coimmunoprecipitation assay followed by mass spectrometry analysis revealed that dCRY interacts with Retinal Degeneration A (RDGA) and with Neither Inactivation Nor Afterpotential C (NINAC) proteins. Both proteins belong to a multiprotein complex (the Signalplex) that includes visual-signaling molecules. Using bioinformatic and molecular approaches, dCRY was found to interact with Neither Inactivation Nor Afterpotential C through Inactivation No Afterpotential D (INAD) in a light-dependent manner and that the CRY-Inactivation No Afterpotential D interaction is mediated by specific domains of the two proteins and involves the CRY C terminus. Moreover, an impairment of the visual behavior was observed in fly mutants for dCRY, indicative of a role, direct or indirect, for this photoreceptor in fly vision