The Physical Mechanism for Retinal Discrete Dark Noise: Thermal Activation or Cellular Ultraweak Photon Emission?

For several decades the physical mechanism underlying discrete dark noise of photoreceptors in the eye has remained highly controversial and poorly understood. It is known that the Arrhenius equation, which is based on the Boltzmann distribution for thermal activation, can model only a part (e.g. half of the activation energy) of the retinal dark noise experimentally observed for vertebrate rod and cone pigments. Using the Hinshelwood distribution instead of the Boltzmann distribution in the Arrhenius equation has been proposed as a solution to the problem. Here, we show that the using the Hinshelwood distribution does not solve the problem completely. As the discrete components of noise are indistinguishable in shape and duration from those produced by real photon induced photo-isomerization, the retinal discrete dark noise is most likely due to ‘internal photons’ inside cells and not due to thermal activation of visual pigments. Indeed, all living cells exhibit spontaneous ultraweak photon emission (UPE), mainly in the optical wavelength range, i.e., 350–700 nm. We show here that the retinal discrete dark noise has a similar rate as UPE and therefore dark noise is most likely due to spontaneous cellular UPE and not due to thermal activation.     

Does Gγ/Aγ ratio and Hb F level influence the severity of sickle cell anaemia

Sickle cell anaemia (SCA) exhibits significant variations in clinical presentation in different populations for which several genetic factors including SCA-associated -and -thalassaemias, G-6-PD deficiency and elevated Hb F level have been implicated as possible ameliorating factors. Saudi Arabia is unique in that mild and severe forms of the disease occur at a high frequency. We investigated the G/A ratio and Hb F level and correlated these values with the severity of SCA. The results showed that Hb F level varies significantly in both groups of patients with no evident correlation with the mild clinical manifestations. However, G/A ratio correlated significantly with the disease severity where a high ratio was observed in patients with the mild and a low ratio in patients with the severe disease. The results are evaluated and discussed in the light of correlation studies and regression analysis.     

Immunoresolvents in asthma and allergic diseases: Review and update

Asthma and allergic diseases are inflammatory conditions developed by excessive reaction of the immune system against normally harmless environmental substances. Although acute inflammation is necessary to eradicate the damaging agents, shifting to chronic inflammation can be potentially detrimental. Essential fatty-acids-derived immunoresolvents, namely, lipoxins, resolvins, protectins, and maresins, are anti-inflammatory compounds that are believed to have protective and beneficial effects in inflammatory disorders, including asthma and allergies. Accordingly, impaired biosynthesis and defective production of immunoresolvents could be involved in the development of chronic inflammation. In this review, recent evidence on the anti-inflam]matory effects of immunoresolvents, their enzymatic biosynthesis routes, as well as their receptors are discussed.     

Matrix metalloproteinase (MMP)-1 and MMP-3 gene variations affect MMP-1 and -3 serum concentration and associates with breast cancer

Molecular Biology Reports - Matrix metallopeptidases (MMPs) 1 and 3 have been shown to contribute to the initiation, and progression of different cancers, including breast cancer (BC). In this...     

Analysis of Allele-Specific Expression in Mouse Liver by RNA-Seq: A Comparison With Cis-eQTL Identified Using Genetic Linkage

We report an analysis of allele-specific expression (ASE) and parent-of-origin expression in adult mouse liver using next generation sequencing (RNA-Seq) of reciprocal crosses of heterozygous F₁ mice from the parental strains C57BL/6J and DBA/2J. We found a 60% overlap between genes exhibiting ASE and putative cis-acting expression quantitative trait loci (cis-eQTL) identified in an intercross between the same strains. We discuss the various biological and technical factors that contribute to the differences. We also identify genes exhibiting parental imprinting and complex expression patterns. Our study demonstrates the importance of biological replicates to limit the number of false positives with RNA-Seq data.     

Two new species of Chrysis Linnaeus (Hymenoptera,Chrysididae) from Iran

The Iranian species in the Chrysis pulchella and C. varidens species groups are investigated. Six species are recognized, two of which are described for the first time: Chrysis gamberoonensis Farhad, Rosa and Talebi sp. nov. and Chrysis brunneamarginata Farhad, Rosa and Talebi sp. nov.. Chrysis gamberoonensis Farhad, Rosa and Talebi sp. nov. belongs to the C. pulchella group and is recognizable within this species group by its unique blue body coloration, scattered mesosoma punctures, polished pit row with elongated pits, and a small median tooth on the lateral edge of metasomal tergum 3. Chrysis brunneamarginata Farhad, Rosa and Talebi sp. nov. belongs to the C. varidens group and is recognizable by the usually colorless apical rim of metasomal tergum 3, and the unique shape of the anterior corners of the scutellum which are enlarged, thickened and directed backward covering the axillary trough. Dichotomous keys and distributional data for Iranian species included in these species groups are provided. Chrysis schwarzi Linsenmaier, 1968 is raised to species rank. The number of Iranian Chrysis species and subspecies is raised to 122.www.zoobank.org/urn:lsid:zoobank.org:pub:F419F860-3B90-4679-9A19-2CF5C255AE6B