Mitochondrial DNA variations in ova and blastocyst: Implications in assisted reproduction

Mitochondrial DNA (mtDNA) of oocyte is critical for its function, embryo quality and development. Analysis of complete mtDNA of 49 oocytes and 18 blastocysts from 67 females opting for IVF revealed 437 nucleotide variations. 40.29% samples had either disease associated or non-synonymous novel or pathogenic mutation in evolutionarily conserved regions. Samples with disease associated mtDNA mutations had low fertilization rate and poor embryo quality, however no difference in implantation or clinical pregnancy rate was observed. Screening mtDNA from oocyte/blastocyst is a simple, clinically reliable method for diagnostic evaluation of female infertility and may reduce risk of mtDNA disease transmission.     

PCR derived molecular markers and phylogenetic relationships in theSecale genus

DNA from 22 different species, accessions, cultivars and lines included in theSecale genus were analyzed by the polymerase chain reaction (PCR), using as primers five pairs of oligonucleotides derived from specific sequences. A total of 42 amplified bands were considered, and some of them appeared to be potentially useful as molecular markers for some of the analyzed groups. These amplified bands were used to generate molecular phenograms inside theSecale genus.     

High mutability in rye (Secale cereale L.).

Analysis of the rye cultivar Ailés of several descents derived from crosses between plants carrying specific genotypes and/or chromosome constitutions resulted in the detection of high chromosome (2.05 x 10(-2)) and gene (9.3 x 10(-3)) mutation frequencies. The existence of a transposon system responsible for this instability is suggested.     

The real-life value of ST2 monitoring during heart failure decompensation: impact on long-term readmission and mortality

Context: Prognostic value of ST2 levels and dynamics has not been investigated in acute heart failure (AHF) using prospective real-life measurements.

Objective: The objective of this study is to investigate the prognostic value of ST2 in AHF.

Methods: ST2 levels were determined at admission (n?=?182) and discharge (n?=?85). Primary endpoint was the composite of all-cause death and HF rehospitalisation at one year.

Results: Discharge ST2 (HR 2.42 [95% CI 1.46–4], p?=?0.001) and ΔST2 (HR 2.32 [95% CI 1.21–4.57], p?=?0.01) but not admission ST2, remained independently prognostic for the primary endpoint after comprehensive multivariable adjustment. ST2 significantly improved prognosis stratification on top of clinical variables and NTproBNP.

Conclusions: Routine clinical use of discharge ST2 and ST2 dynamics provide independent prognostic information.     

Glassy State and Cryopreservation of Mint Shoot Tips

Vitrification refers to the physical process by which a liquid supercools to very low temperatures and finally solidifies into a metastable glass, without undergoing crystallization at a practical cooling rate. Thus, vitrification is an effective freeze‐avoidance mechanism and living tissue cryopreservation is, in most cases, relying on it. As a glass is exceedingly viscous and stops all chemical reactions that require molecular diffusion, its formation leads to metabolic inactivity and stability over time. To investigate glassy state in cryopreserved plant material, mint shoot tips were submitted to the different stages of a frequently used cryopreservation protocol (droplet‐vitrification) and evaluated for water content reduction and sucrose content, as determined by ion chromatography, frozen water fraction and glass transitions occurrence by differential scanning calorimetry, and investigated by low‐temperature scanning electron microscopy, as a way to ascertain if their cellular content was vitrified. Results show how tissues at intermediate treatment steps develop ice crystals during liquid nitrogen cooling, while specimens whose treatment was completed become vitrified, with no evidence of ice formation. The agreement between calorimetric and microscopic observations was perfect. Besides finding a higher sucrose concentration in tissues at the more advanced protocol steps, this level was also higher in plants precultured at 25/?1°C than in plants cultivated at 25°C. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:707–717, 2013     

Interallelic complementation provides genetic evidence for the multimeric organization of the Phycomyces blakesleeanus phytoene dehydrogenase.

The Phycomyces blakesleeanus wild-type is yellow, because it accumulates beta-carotene as the main carotenoid. A new carotenoid mutant of this fungus (A486) was isolated, after treatment with ethyl methane sulfonate (EMS), showing a whitish coloration. It accumulates large amounts of phytoene, small quantities of phytofluene, zeta-carotene and neurosporene, in decreasing amounts, and traces of beta-carotene. This phenotype indicates that it carries a leaky mutation affecting the enzyme phytoene dehydrogenase (EC 1.3.-.-), which is specified by the gene carB. Biochemical analysis of heterokaryons showed that mutant A486 complements two previously characterized carB mutants, C5 (carB10) and S442 (carB401). Sequence analysis of the carB gene genomic copy from these three strains revealed that they are all altered in the gene carB, giving information about the nature of the mutation in each carB mutant allele. The interallelic complementation provides evidence for the multimeric organization of the P. blakesleeanus phytoene dehydrogenase.     

Plasticity and genetic effects contribute to different axes of neural divergence in a community of mimetic Heliconius butterflies

Changes in ecological preference, often driven by spatial and temporal variation in resource distribution, can expose populations to environments with divergent information content. This can lead to adaptive changes in the degree to which individuals invest in sensory systems and downstream processes, to optimize behavioural performance in different contexts. At the same time, environmental conditions can produce plastic responses in nervous system development and maturation, providing an alternative route to integrating neural and ecological variation. Here, we explore how these two processes play out across a community of Heliconius butterflies. Heliconius communities exhibit multiple Mullerian mimicry rings, associated with habitat partitioning across environmental gradients. These environmental differences have previously been linked to heritable divergence in brain morphology in parapatric species pairs. They also exhibit a unique dietary adaptation, known as pollen feeding, that relies heavily on learning foraging routes, or trap-lines, between resources, which implies an important environmental influence on behavioural development. By comparing brain morphology across 133 wild-caught and insectary-reared individuals from seven Heliconius species, we find strong evidence for interspecific variation in patterns of neural investment. These largely fall into two distinct patterns of variation; first, we find consistent patterns of divergence in the size of visual brain components across both wild and insectary-reared individuals, suggesting genetically encoded divergence in the visual pathway. Second, we find interspecific differences in mushroom body size, a central component of learning and memory systems, but only among wild caught individuals. The lack of this effect in common-garden individuals suggests an extensive role for developmental plasticity in interspecific variation in the wild. Finally, we illustrate the impact of relatively small-scale spatial effects on mushroom body plasticity by performing experiments altering the cage size and structure experienced by individual H. hecale. Our data provide a comprehensive survey of community level variation in brain structure, and demonstrate that genetic effects and developmental plasticity contribute to different axes of interspecific neural variation.