Persistence of a small subpopulation of cancer stem-like cells in the C6 glioma cell line

Both stem cells and cancer cells are thought to be capable of unlimited proliferation. Paradoxically, however, some cancers seem to contain stem-like cells (cancer stem cells). To help resolve this paradox, we investigated whether established malignant cell lines, which have been maintained for years in culture, contain a subpopulation of stem cells. In this article, we show that many cancer cell lines contain a small side population (SP), which, in many normal tissues, is thought to contain the stem cells of the tissue. We demonstrate that in the absence of serum the combination of basic fibroblast growth factor and platelet-derived growth factor maintains SP cells in the C6 glioma cell line. Moreover, we show that C6 SP cells, but not non-SP cells, can generate both SP and non-SP cells in culture and are largely responsible for the in vivo malignancy of this cell line. Finally, we provide evidence that C6 SP cells can produce both neurons and glial cells in vitro and in vivo. We propose that many cancer cell lines contain a minor subpopulation of stem cells that is enriched in an SP, can be maintained indefinitely in culture, and is crucial for their malignancy.     

Dynamic Tensile Properties and Energy Dissipation of High-Strength Concrete after Exposure to Elevated Temperatures

In view of the devastating outcomes of fires and explosions, it is imperative to research the dynamic responses of concrete structures at high temperatures. For this purpose, the effects of the strain rate and high temperatures on the dynamic tension behavior and energy characteristics of high-strength concrete were investigated in this paper. Dynamic tests were conducted on high-strength concrete after exposure to the temperatures of 200, 400, and 600 °C by utilizing a 74 mm diameter split Hopkinson pressure bar (SHPB) apparatus. We found that the quasi-static and dynamic tensile strength of high-strength concrete gradually decreased and that the damage degree rose sharply with the rise of temperature. The dynamic tensile strength and specific energy absorption of high-strength concrete had a significant strain rate effect. The crack propagation law gradually changed from directly passing through the coarse aggregate to extending along the bonding surface between the coarse aggregate and the mortar matrix with the elevation of temperature. When designing the material ratio, materials with high-temperature resistance and high tensile strength should be added to strengthen the bond between the mortar and the aggregate and to change the failure mode of the structure to resist the softening effect of temperature.     

Clinical and genetic analysis in a family with familial renal glucosuria: Identification of an N101K mutation in the sodium–glucose cotransporter 2 encoded by a solute carrier family 5 member 2 gene

We report the identification of a mutation in the solute carrier family 5 member 2 (SLC5A2) gene, which encodes sodium–glucose cotransporter 2, in a family with familial renal glucosuria. The proband was a 26‐year‐old Japanese man referred to the diabetes division with repeated glucosuria without hyperglycemia. His mother, uncle and grandfather also had a history of glucosuria. A heterozygous missense mutation (c.303T>A:p.N101K) in SLC5A2 was identified in the patient and his mother, but not in 200 chromosomes from 100 healthy and unrelated individuals, or in 3,408 Japanese individuals in the Tohoku Medical Megabank. Furthermore, bioinformatics software predicted that this lesion would be pathogenic. We infer that the mutation led to clinically relevant sodium–glucose cotransporter 2 dysfunction. The patient showed no symptoms of hypoglycemia, but continuous glucose monitoring confirmed asymptomatic hypoglycemia.     

A novel analytical strategy for patient–physician communication research: The one-with-many design

Objective

We aimed to demonstrate how a novel analytic strategy – the one-with-many (OWM) design – can provide unique information about patient–physician communication that cannot be obtained using traditional analytic strategies.

Methods

Using an OWM design we conducted a secondary analysis of behavioral (talk time) and self-reported (perceived teamness) data from a study of patient–physician communication, and examined variance decompositions of these variables.

Results

Talk time was largely relational, suggesting that there is no behavioral consistency on the part of physicians across patients or behavioral similarity among patients who see the same physician. In contrast, there was significant actor variance in perceived teamness, suggesting that some physicians consistently reported higher teamness with their patients than others. However, those physicians’ positive perceptions of the communication are not necessarily reciprocated by their patients.

Conclusions

OWM design provides researchers with the opportunity to take full advantage of rich non-independent data and explore interesting communication patterns (e.g., behavioral continuity, similarity, reciprocity unique to specific dyads) that have been omitted in prior literature.

Practical implications

OWM can be used to determine the relative differences in how patients and physicians influence communication patterns and identify which aspects of physician–patient communication are relational and which are not.