Improving quantitative real-time RT-PCR reproducibility by boosting primer-linked amplification efficiency

The effect of primer selection on real-time polymerase chain reaction (RT-PCR) performance was tested. Primer sets of varying length of product were used to amplify the sequence of -actin. Variability in length caused variability in RT-PCR performance. Kinetic parameters of PCR were studied by mathematical approximation of real-time data by means of a four-parametric sigmoid model. This model describes the full kinetics of the amplification trajectory. Statistical exploration of parameters yielded by this model revealed that reactions with higher amplification efficiency – primed by well-performing primers – proceed with lower variability and are therefore better suited for measurement purposes.     

Large-Scale Phosphoproteomics Reveals Shp-2 Phosphatase-Dependent Regulators of Pdgf Receptor Signaling

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Craniofacial characteristics of Croatian and Syrian populations

Craniofacial area is apart of the human body which undergoes the greatest changes during development and is characterized by uneven growth. External and internal factors affect the growth and development of craniofacial structures. They are responsible for the occurrence of specific craniofacial characteristics in different races or populations within the same race. The present study investigates the possible differences of the basic head and face shapes between the Croatian and Syrian populations. The sample included 400 subjects of both sexes aged 18-24 years and was divided into a Croatian and a Syrian group with 200 subjects each. Six variables defined according to Martin and Saller were measured by standard anthropometric instruments. The results of the study demonstrated statistically significant differences between our subjects in all variables except face width. The dolichocephalic head type and the mesoprosopic face type were predominant in the Croatian population, while the brachycephalic head type and the euryprosopic face type dominated in the Syrian population.     

Contrasting life-history traits of two sympatric smooth-hound species: implication for vulnerability

In this study, life-history traits (maximum and average size, size at maturity and fecundity) of two congeneric smooth-hounds, Mustelus mustelus and Mustelus punctulatus, which share a geographical distribution and experience a similar fishing exploitation, were estimated and compared between species. The results indicated a lower maximum and average size, a lower size at maturity and a higher fecundity in M. punctulatus compared with those in M. mustelus. Considering that these two species co-occur in the same areas and are caught by the same fishing gears, the results indicate a higher vulnerability to exploitation of M. mustelus compared with that of M. punctulatus.     

Effect of Cannabis sativa L. root,leaf and inflorescence ethanol extracts on the chemotrophic response of entomopathogenic nematodes

Plant and Soil - Soils represent the natural habitat of entomopathogenic nematodes (EPNs). When moving in soil, EPNs are oriented to follow a chemical signal (chemotaxis). Cannabis sativa L. is...     

Helicobacter pylori infection and acute myocardial infarction

The aim of this investigation was to determine whether H. pylori infection is an independent risk factor for acute myocardial infarction (AMI), determine is there a link between H. pylori infection and severity of disease. In this prospective, single centre study, were enrolled 100 patients with AMI and control group was consisted 93 healthy individuals. The results of this study showed no difference between H. pylori seropositivity distribution in the investigate and control group (29 vs. 26 %) and there was no significant difference on the severity of the disease. There was significant association in the patients with three and more risk factors, where the patients with lower blood pressure (124.4/77.4 vs. 145.9/87.7 mmHg) and better controlled diabetes (HbA1c 6.1% vs. 6.9%) had greater risk for AMI if they are H. pylori seropositive. The large multicentric trials would be needed to define a precise role of H. pylori infection on the developement of AMI.     

XMAP215–EB1 Interaction Is Required for Proper Spindle Assembly and Chromosome Segregation in Xenopus Egg Extract

In metaphase Xenopus egg extracts, global microtubule growth is mainly promoted by two unrelated microtubule stabilizers, end-binding protein 1 (EB1) and XMAP215. Here, we explore their role and potential redundancy in the regulation of spindle assembly and function. We find that at physiological expression levels, both proteins are required for proper spindle architecture: Spindles assembled in the absence of EB1 or at decreased XMAP215 levels are short and frequently multipolar. Moreover, the reduced density of microtubules at the equator of ΔEB1 or ΔXMAP215 spindles leads to faulty kinetochore–microtubule attachments. These spindles also display diminished poleward flux rates and, upon anaphase induction, they neither segregate chromosomes nor reorganize into interphasic microtubule arrays. However, EB1 and XMAP215 nonredundantly regulate spindle assembly because an excess of XMAP215 can compensate for the absence of EB1, whereas the overexpression of EB1 cannot substitute for reduced XMAP215 levels. Our data indicate that EB1 could positively regulate XMAP215 by promoting its binding to the microtubules. Finally, we show that disruption of the mitosis-specific XMAP215–EB1 interaction produces a phenotype similar to that of either EB1 or XMAP215 depletion. Therefore, the XMAP215–EB1 interaction is required for proper spindle organization and chromosome segregation in Xenopus egg extracts.     

NK cell lymphoma, nasal type, with massive lung involvement: a case report

Extranodal NK/T cell lymphoma, nasal type, is an Epstein–Barr virus-associated lymphoma that most commonly involves the nasal cavity and upper respiratory tract. Lung involvement by NK/T cell lymphoma is rare and seldom reported in the literature. We describe the unusual case of a 41-year-old male with NK cell lymphoma, nasal type, who presented with massive secondary lung involvement 2.5 years after the detection of a retroperitoneal mass. The diagnosis was made by open lung biopsy. Despite aggressive treatment, the patient died shortly after the initiation of therapy. Lung involvement by NK/T cell lymphoma occurs most commonly as part of widely disseminated disease and carries a poor prognosis for the patient. Novel agents and innovative therapies need to be developed for this aggressive lymphoma.     

Size-dependent palindrome-induced intrachromosomal recombination in yeast

Palindromic and quasi-palindromic sequences are important DNA motifs found in various cis-acting genetic elements, but are also known to provoke different types of genetic alterations. The instability of such motifs is clearly size-related and depends on their potential to adopt secondary structures known as hairpins and cruciforms. Here we studied the influence of palindrome size on recombination between two directly repeated copies of the yeast CYC1 gene leading to the loss of the intervening sequence (“pop-out” recombination). We show that palindromes inserted either within one copy or between the two copies of the CYC1 gene become recombinogenic only when they attain a certain critical size and we estimate this critical size to be about 70 bp. With the longest palindrome used in this study (150 bp) we observed a more than 20-fold increase in the pop-out recombination. In the sae2/com1 mutant the palindrome-stimulated recombination was completely abolished. Suppression of palindrome recombinogenicity may be crucial for the maintenance of genetic stability in organisms containing a significant number of large palindromes in their genomes, like humans.