Barrelettes without Barrels in the American Water Shrew

Water shrews (Sorex palustris) depend heavily on their elaborate whiskers to navigate their environment and locate prey. They have small eyes and ears with correspondingly small optic and auditory nerves. Previous investigations have shown that water shrew neocortex is dominated by large representations of the whiskers in primary and secondary somatosensory cortex (S1 and S2). Flattened sections of juvenile cortex processed for cytochrome oxidase revealed clear borders of the whisker pad representation in S1, but no cortical barrels. We were therefore surprised to discover prominent barrelettes in brainstem of juvenile water shrews in the present investigation. These distinctive modules were found in the principal trigeminal nucleus (PrV), and in two of the three spinal trigeminal subnuclei (interpolaris – SpVi and caudalis – SpVc). Analysis of the shrew''s whisker pad revealed the likely relationship between whiskers and barrelettes. Barrelettes persisted in adult water shrew PrV, but barrels were also absent from adult cortex. Thus in contrast to mice and rats, which have obvious barrels in primary somatosensory cortex and less clear barrelettes in the principal nucleus, water shrews have clear barrelettes in the brainstem and no barrels in the neocortex. These results highlight the diverse ways that similar mechanoreceptors can be represented in the central nervous systems of different species.     

Effect of exercise and thermal stress on plasma volume.

Six male subjects exercised for 50 min at 25% (light exercise) and 55% (moderate exercise) of their estimated aerobic capacities in environments of 42 degrees C db, 35 degrees C wb and 30 degrees C db, 24 degrees C wb, respectively. Alterations in the hematocrit, hemoglobin, and plasma protein concentrations, and in the activity of an injected aliquot of isotopically labeled albumin were each used to calculate the percentage change in plasma volume occurring during exercise and recovery. Changes in each measure were consistent with a reduction in plasma volume during exercise and a return to preexercise levels during recovery. There was no significant difference between the measures when exercising in the heat, but during the more severe exercise in the cooler environment disproportional changes in protein, hematocrit, and hemoglobin were observed. Disproportional changes were also seen during the recovery phase, when the hematocrit and hemoglobin concentration indicated a more rapid return of the plasma volume to preexercise levels than did either the plasma protein concentration or albumin activity. During moderate exercise and recovery there was a 1% decrease in red cell volume. It is concluded that exercise accelerates the rate of protein movement from extravascular compartments to the intravascular compartment, leading to elevated plasma protein levels during recovery which favor the return of water to the intravascular space. Hemoglobin concentration is considered to be the most reliable measure of plasma volume change during exercise.     

Immunological microenvironment gene expression in patients with diffuse large B cell non Hodgkin lymphoma

BackgroundNon Hodgkin lymphoma (NHL) is one of the immune system cancers. The occurrence and progression of malignant lymphomas depends on cellular pathways deregulation. Understanding the relationship between the immune system at the genetic level and malignant transformation is critical to reach its etiology.ObjectiveThe aim of this work is to evaluate the expression of five immune related genes (PD-1, FOXP3, GrA, GrB and CD11c) in patients with diffuse large B cell non Hodgkin lymphoma (DLBCL).Materials and methodsThis study was conducted on fifty patients with DLBCL and fifty sex and age matched apparently healthy subjects. The participants were subjected to these laboratory investigations: complete blood count, serum lactate dehydrogenase and β2microglobulin (β₂M) levels and determination of PD-1, FOXP3, GrA, GrB and CD11c gene expressions.ResultsThe results of this study revealed that PD-1, FOXP3, GrA, GrB and CD11c gene expressions were significantly increased in DLBCL patients.ConclusionPatients with DLBCL have variablePD-1, FOXP3,GrA, GrB and CD11cgene expressions levels, which are correlated with the overall survival (OS) indicating that they can be good predictors of outcome in these patients.     

A pilot study on the relation between irisin single-nucleotide polymorphism and risk of myocardial infarction

BackgroundMyocardial infarction (MI) is the major cause of death and disability worldwide. Many recent studies revealed the relationship between circulating irisin levels, endothelial dysfunctions and subclinical atherosclerosis in adult patients.ObjectivesThe aim of this study was to investigate the distribution of Irisin gene single nucleotide polymorphism in patients with MI and its association with other clinical and laboratory variables in these patients.Patients and methodsThis study was carried out in 100 patients with MI, and 100 healthy subjects served as controls. All studied subjects underwent laboratory investigations, including measurement of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-c) high-density lipoprotein cholesterol (HDL-c), creatinine kinase-MB (CK-MB), troponin I (TnI) and genotyping of rs 3480 and rs726344 of Irisin genes using the TaqMan Allelic Discrimination assay technique.ResultsThere was a significant difference of Irisin genotypes in patients when compared to controls. By estimating odd ratio (OR) an association was found between G allele of rs 3480 and A allele of rs726344with increase the risk of developing myocardial infarction by 4.03 and 3.47 fold respectively. GG of rs 3480 carriers had significantly increased Troponin I and triglyceride levels, while GA carriers of rs726344 had significantly increased CKMB, Total cholesterol, LDLc, HDLc, troponin I and triglyceride levels compared with other genotypes.ConclusionG allele of rs 3480 and A allele of rs726344can considered as genetic risk factors for MI; these findings could have an impact on preventive strategy for myocardial infarction.     

Characterisation of an unusual telomere motif (TTTTTTAGGG)n in the plant Cestrum elegans (Solanaceae), a species with a large genome

The characterization of unusual telomere sequence sheds light on patterns of telomere evolution, maintenance and function. Plant species from the closely related genera Cestrum, Vestia and Sessea (family Solanaceae) lack known plant telomeric sequences. Here we characterize the telomere of Cestrum elegans, work that was a challenge because of its large genome size and few chromosomes (1C 9.76 pg; n = 8). We developed an approach that combines BAL31 digestion, which digests DNA from the ends and chromosome breaks, with next‐generation sequencing (NGS), to generate data analysed in RepeatExplorer, designed for de novo repeats identification and quantification. We identify an unique repeat motif (TTTTTTAGGG)_n in C. elegans, occurring in ca. 30 400 copies per haploid genome, averaging ca. 1900 copies per telomere, and synthesized by telomerase. We demonstrate that the motif is synthesized by telomerase. The occurrence of an unusual eukaryote (TTTTTTAGGG)_n telomeric motif in C. elegans represents a switch in motif from the ‘typical’ angiosperm telomere (TTTAGGG)_n. That switch may have happened with the divergence of Cestrum, Sessea and Vestia. The shift in motif when it arose would have had profound effects on telomere activity. Thus our finding provides a unique handle to study how telomerase and telomeres responded to genetic change, studies that will shed more light on telomere function.     

SET nuclear oncogene associates with microcephalin/MCPH1 and regulates chromosome condensation

Primary microcephaly is an autosomal recessive disorder characterized by marked reduction in human brain size. Microcephalin (MCPH1), one of the genes mutated in primary microcephaly, plays an important role in DNA damage checkpoint control and mitotic entry. Additionally, MCPH1 ensures the proper temporal activation of chromosome condensation during mitosis, by acting as a negative regulator of the condensin II complex. We previously found that deletion of the of the MCPH1 N terminus leads to the premature chromosome condensation (PCC) phenotype. In the present study, we unexpectedly observed that a truncated form of MCPH1 appears to be expressed in MCPH1(S25X/S25X) patient cells. This likely results from utilization of an alternative translational start codon, which would produce a mutant MCPH1 protein with a small deletion of its N-terminal BRCT domain. Furthermore, missense mutations in the MCPH1 cluster at its N terminus, suggesting that intact function of this BRCT protein-interaction domain is required both for coordinating chromosome condensation and human brain development. Subsequently, we identified the SET nuclear oncogene as a direct binding partner of the MCPH1 N-terminal BRCT domain. Cells with SET knockdown exhibited abnormal condensed chromosomes similar to those observed in MCPH1-deficient mouse embryonic fibroblasts. Condensin II knockdown rescued the abnormal chromosome condensation phenotype in SET-depleted cells. In addition, MCPH1 V50G/I51V missense mutations, impair binding to SET and fail to fully rescue the abnormal chromosome condensation phenotype in Mcph1(-/-) mouse embryonic fibroblasts. Collectively, our findings suggest that SET is an important regulator of chromosome condensation/decondensation and that disruption of the MCPH1-SET interaction might be important for the pathogenesis of primary microcephaly.