Human β-Synuclein Rendered Fibrillogenic by Designed Mutations

Filamentous inclusions made of α-synuclein are found in nerve cells and glial cells in a number of human neurodegenerative diseases, including Parkinson disease, dementia with Lewy bodies, and multiple system atrophy. The assembly and spreading of these inclusions are likely to play an important role in the etiology of common dementias and movement disorders. Both α-synuclein and the homologous β-synuclein are abundantly expressed in the central nervous system; however, β-synuclein is not present in the pathological inclusions. Previously, we observed a poor correlation between filament formation and the presence of residues 73–83 of α-synuclein, which are absent in β-synuclein. Instead, filament formation correlated with the mean β-sheet propensity, charge, and hydrophilicity of the protein (global physicochemical properties) and β-strand contiguity calculated by a simple algorithm of sliding averages (local physicochemical property). In the present study, we rendered β-synuclein fibrillogenic via one set of point mutations engineered to enhance global properties and a second set engineered to enhance predominantly β-strand contiguity. Our findings show that the intrinsic physicochemical properties of synucleins influence their fibrillogenic propensity via two distinct but overlapping modalities. The implications for filament formation and the pathogenesis of neurodegenerative diseases are discussed.     

Kinetics of Cr(VI) Removal by Iron Filings in Some Soils

In this research, kinetics of Cr(VI) reduction by iron filings was investigated through a batch study in seven different soils. Chromate reduction experiments were carried out for initial Cr(VI) concentrations ranging from 20 to 100 mgkg^?1 and iron filings dosage of 0 to 5% w/w. The experimental data were analyzed using various kinetic models including zero-order, pseudo first-order, power function, Elovich, and diffusion parabolic. Results showed that the Cr(VI) reduction efficiency in the presence of all studied soils increased with increasing iron filings dosage and decreased with increasing the initial Cr(VI) concentration. The reaction rates considerably depended on pH and were higher in acidic soils. The diffusion parabolic model was the best kinetic model as evidenced by the highest determination coefficient (r²) and the lowest standard error of the estimate (SE). The rate-limiting step(s) may be transport of chromate anions across a liquid film at the interface of soil-liquid, transport in liquid-filled macropores of iron filings aggregates, or diffusion in micropores and along the particle's surface.     

An Augmented SMS Intervention to Improve Access to Antenatal CD4 Testing and ART Initiation in HIV-Infected Pregnant Women: A Cluster Randomized Trial

BackgroundLess than one-third of HIV-infected pregnant women eligible for combination antiretroviral therapy (ART) globally initiate treatment prior to delivery, with lack of access to timely CD₄ results being a principal barrier. We evaluated the effectiveness of an SMS-based intervention to improve access to timely antenatal ART.MethodsWe conducted a stepped-wedge cluster randomized trial of a low-cost programmatic intervention in 20 antenatal clinics in Gaborone, Botswana. From July 2011-April 2012, 2 clinics were randomly selected every 4 weeks to receive an ongoing clinic-based educational intervention to improve CD₄ collection and to receive CD₄ results via an automated SMS platform with active patient tracing. CD₄ testing before 26 weeks gestation and ART initiation before 30 weeks gestation were assessed.ResultsThree-hundred-sixty-six ART-naïve women were included, 189 registering for antenatal care under Intervention and 177 under Usual Care periods. Of CD₄-eligible women, 100 (59.2%) women under Intervention and 79 (50.6%) women under Usual Care completed CD₄ phlebotomy before 26 weeks gestation, adjusted odds ratio (aOR, adjusted for time that a clinic initiated Intervention) 0.87 (95% confidence interval [CI]0.47–1.63, P = 0.67). The SMS-based platform reduced time to clinic receipt of CD₄ test result from median of 16 to 6 days (P<0.001), was appreciated by clinic staff, and was associated with reduced operational cost. However, rates of ART initiation remained low, with 56 (36.4%) women registering under Intervention versus 37 (24.2%) women under Usual Care initiating ART prior to 30 weeks gestation, aOR 1.06 (95%CI 0.53–2.13, P = 0.87).ConclusionsThe augmented SMS-based intervention delivered CD₄ results more rapidly and efficiently, and this type of SMS-based results delivery platform may be useful for a variety of tests and settings. However, the intervention did not appear to improve access to timely antenatal CD₄ testing or ART initiation, as obstacles other than CD₄ impeded ART initiation during pregnancy.     

Seed and gland morphology in Euphorbia (Euphorbiaceae) with focus on their systematic and phylogenetic importance, a case study in Iranian highlands

A comprehensive study based on gland and seed micromorphology in Euphorbia (Euphorbiaceae) for species distributed in Iranian highlands is presented. A total of 86 species were studied. The gland structure was examined by direct field observations. Taxonomically important characters of glands were observed and measured: size, texture, shape, color, and horns. For species out of Iran herbarium materials were studied. Seed characteristics were examined using scanning electron microscopy (SEM) as well as dissecting light microscopy. Significant features are: seed size, seed shape, presence of caruncle, shape of caruncle, and seed surface ornamentation. A phylogenetic study using Maximum Parsimony (MP) and Bayesian Inference (BI) was performed based on sequences of nuclear DNA internal transcribed spacers (ITS) for selected species representing the main clades known in Euphorbia and with special focus on the species distributed in Iranian highlands. ITS sequences for 20 accessions representing 19 species are provided for the first time, and 48 accessions of 47 species were used from GenBank. The topologies of both analyses were congruent. The results indicate: (1) four main clades with high supports in subgen. Esula which are appropriate to be recognized at sectional rank. (2) E. larica is nested within clade A including few members of subgen. Rhizanthium and is closely related to sect. Balsamis, which is suggested here to be transferred from subgen. Esula into subgen. Rhizanthium. (3) E. osyridea of the monotypic subsect. Osyrideae is closely related to E. buhsei and to the members of sect. Esula. Tracing morphological characters on the phylogenetic tree shows that several morphological characters, such as seed ornamentation applied in previous subgeneric classification of the subgen. Esula, are homoplasious, but the gland structure and capsule surface characters are more reliable for classification purposes.     

Effect of In Ovo Feeding of the Vitamin B12 on Hatchability,Performance and Blood Constitutes in Broiler Chicken

International Journal of Peptide Research and Therapeutics - The aim of the current study was to determine effect of in ovo feeding of vitamin B12 on hatchability, growth performance and blood...     

Kavosh: a new algorithm for finding network motifs

Background  

Complex networks are studied across many fields of science and are particularly important to understand biological processes. Motifs in networks are small connected sub-graphs that occur significantly in higher frequencies than in random networks. They have recently gathered much attention as a useful concept to uncover structural design principles of complex networks. Existing algorithms for finding network motifs are extremely costly in CPU time and memory consumption and have practically restrictions on the size of motifs.