Changes in exon-intron structure during vertebrate evolution affect the splicing pattern of exons

Exon-intron architecture is one of the major features directing the splicing machinery to the short exons that are located within long flanking introns. However, the evolutionary dynamics of exon-intron architecture and its impact on splicing is largely unknown. Using a comparative genomic approach, we analyzed 17 vertebrate genomes and reconstructed the ancestral motifs of both 3' and 5' splice sites, as also the ancestral length of exons and introns. Our analyses suggest that vertebrate introns increased in length from the shortest ancestral introns to the longest primate introns. An evolutionary analysis of splice sites revealed that weak splice sites act as a restrictive force keeping introns short. In contrast, strong splice sites allow recognition of exons flanked by long introns. Reconstruction of the ancestral state suggests these phenomena were not prevalent in the vertebrate ancestor, but appeared during vertebrate evolution. By calculating evolutionary rate shifts in exons, we identified cis-acting regulatory sequences that became fixed during the transition from early vertebrates to mammals. Experimental validations performed on a selection of these hexamers confirmed their regulatory function. We additionally revealed many features of exons that can discriminate alternative from constitutive exons. These features were integrated into a machine-learning approach to predict whether an exon is alternative. Our algorithm obtains very high predictive power (AUC of 0.91), and using these predictions we have identified and successfully validated novel alternatively spliced exons. Overall, we provide novel insights regarding the evolutionary constraints acting upon exons and their recognition by the splicing machinery.     

The impact of PEGylation on protein immunogenicity

Covalent attachment of PEG (PEGylation) is widely used to improve the pharmaceutical properties of therapeutic proteins. The applicability and safety of this method have been proven by the use of various PEGylated pharmaceutical proteins approved by the Food and Drug Administration (FDA). One of the properties attributed to PEGylation is immunogenicity reduction of the PEGylated protein. In this study, the impact of PEGylation on immunogenicity was tested and compared for two proteins (chicken IgY and horse IgG) in two strains of mice (Balb/c and C57BL/6) for two routes of administration (i.v. and i.m.) and two sizes of PEG (5 kD and 20 kD). The influence of PEG was shown to be inconsistent between the mouse strains and routes of administration, even with the same tested protein. Consequently, immunogenicity reduction by PEGylation cannot be predicted or assumed; it must be tested on an individual case basis.     

Ocular antisense oligonucleotide delivery by cationic nanoemulsion for improved treatment of ocular neovascularization: an in-vivo study in rats and mice

The efficacy of an antisense oligonucleotide (ODN17) cationic nanoemulsion directed at VEGF-R2 to reduce neovascularization was evaluated using rat corneal neovascularization and retinopathy of prematurity (ROP) mouse models. Application of saline solution or scrambled ODN17 solution on eyes of rats led to the highest extent of corneal neovascularization. The groups treated with blank nanoemulsion or scrambled ODN17 nanoemulsion showed moderate inhibition in corneal neovascularization with no significant difference with the saline and scrambled ODN17 control solution groups, while the groups treated with ODN17 solution or Avastin? (positive ODN17 control) clearly elicited marked significant inhibition in corneal neovascularization confirming the results reported in the literature. The highest significant corneal neovascularization inhibition efficiency was noted in the groups treated with ODN17 nanoemulsion (topical and subconjunctivally). However, in the ROP mouse model, the ODN17 in PBS induced a 34% inhibition of retinal neovascularization when compared to the aqueous-vehicle-injected eyes. A significantly higher inhibition of vitreal neovascularization (64%) was observed in the group of eyes treated with ODN17 nanoemulsion. No difference in extent of neovascularization was observed between blank nanoemulsion, scrambled ODN17 nanoemulsion, vehicle or non-treated eyes. The overall results indicate that cationic nanoemulsion can be considered a promising potential ocular delivery system and an effective therapeutic tool of high clinical significance in the prevention and forthcoming treatment of ocular neovascular diseases.     

Screening and Diagnosis of Gestational Diabetes Mellitus: Critical appraisal of the new International Association of Diabetes in Pregnancy Study Group recommendations on a national level

OBJECTIVE To study the implications of implementing the International Association of Diabetes in Pregnancy Study Group (IADPSG) recommendations for screening and diagnosis of gestational diabetes mellitus (GDM) in Israel and explore alternative methods for identifying women at risk for adverse pregnancy outcomes. RESEARCH DESIGN AND METHODS We analyzed data of the Israeli Hyperglycemia and Adverse Pregnancy Outcomes study participants (N = 3,345). Adverse outcome rates were calculated and compared for women who were positive according to 1) IADPSG criteria, 2) IADPSG criteria with risk stratification, or 3) screening with BMI or fasting plasma glucose (FPG). RESULTS Adopting IADPSG recommendations would increase GDM diagnosis by ～50%. One-third of IADPSG-positive women were at low risk for adverse outcomes and could be managed less intensively. FPG ≥89 mg/dL or BMI ≥33.5 kg/m(2) at 28-32 weeks of gestation detected proportions of adverse outcomes similar to IADPSG criteria. CONCLUSIONS Implementing IADPSG recommendations will substantially increase GDM diagnosis. Risk stratification in IADPSG-positive women may reduce over-treatment. Screening with FPG or BMI may be a practical alternative.     

Adolescents and adults coordination questionnaire: development and psychometric properties

OBJECTIVE. This article describes the development of a brief, ecologically valid, self-report questionnaire, the Adolescents and Adults Coordination Questionnaire (AAC-Q), used to identify developmental coordination disorder (DCD) in adolescents and adults.METHOD. The AAC-Q was completed by 28 adolescents and adults with suspected DCD ages 16-35 yr (mean [M] age = 21.18 yr) and 28 peers without DCD (M age = 27.64 yr). Cutoff scores for suspected DCD were established using data from a sample of 2,379 participants ages 19-25 yr (M age = 20.68 yr).RESULTS. Reliability of the AAC-Q was determined using Cronbach's α (α = .88) and test-retest reliability (r = .94, p < .001). Independent-sample t tests to assess construct validity revealed significant differences between participants with and without DCD, t(27) = 9.37, p < .001.CONCLUSION. The AAC-Q is a standardized, reliable, and valid tool with potential for both research and clinical use.     

Neonatal Midaortic Syndrome and Renal Artery Atresia Presenting as Malignant Hypertension

We report a case of congenital midaortic syndrome with bilateral renal artery atresia in a premature female neonate born by way of caesarean section secondary to acute onset of decreased fetal movement and polyhydramnios. The infant required cardiopulmonary resuscitation at birth, and initial echocardiogram exhibited normal intracardiac anatomy and mildly depressed left-ventricular systolic function. Within 24 h, the neonate developed severe systemic arterial hypertension and acute renal failure. Ultrasound demonstrated hyperechoic kidneys and a hypoplastic abdominal aorta. Angiography revealed severe suprarenal hypoplasia of the abdominal aorta with bilateral renal artery atresia. Medical support was withdrawn, and the patient died shortly thereafter.     

Global connectivity of prefrontal cortex predicts cognitive control and intelligence

Control of thought and behavior is fundamental to human intelligence. Evidence suggests a frontoparietal brain network implements such cognitive control across diverse contexts. We identify a mechanism--global connectivity--by which components of this network might coordinate control of other networks. A lateral prefrontal cortex (LPFC) region's activity was found to predict performance in a high control demand working memory task and also to exhibit high global connectivity. Critically, global connectivity in this LPFC region, involving connections both within and outside the frontoparietal network, showed a highly selective relationship with individual differences in fluid intelligence. These findings suggest LPFC is a global hub with a brainwide influence that facilitates the ability to implement control processes central to human intelligence.