Comment on "In vivo flow cytometry reveals a circadian rhythm of circulating tumor cells"

Dear Editor, Circulating tumor cells (CTCs) are instrumental in hematogenous metastasis and are widely studied using liquid biopsy methods.     

Altruism on American Television: Examining the Amount of, and Context Surrounding, Acts of Helping and Sharing

Using a representative sample of television content featuring 2,227 programs across different genres and 18 different channels, the frequency and context of altruistic actions were content analyzed. A social cognitive theory approach was taken to guide the selection of contextual variables. The results showed that 73% of the programs in the sample featured instances of helping/sharing at a rate of 2.92 incidents per hour. Further, the actions were most likely to be initiated by adult White males and many acts were depicted in a humorous, realistic, and rewarding context. In terms of channel differences, shows on children's basic cable featured not only the highest proportion of programs with one or more instances of altruism but also the highest rate per hour (4.02 acts). Differences in contextual features and channel type are discussed in terms of social cognitive theory below.     

Nanoparticle Accumulation in Angiogenic Tissues: Towards Predictable Pharmacokinetics

Nanoparticles are increasingly used in medical applications such as drug delivery, imaging, and biodiagnostics, particularly for cancer. The design of nanoparticles for tumor delivery has been largely empirical, owing to a lack of quantitative data on angiogenic tissue sequestration. Using fluorescence correlation spectroscopy, the deposition rate constants of nanoparticles into angiogenic blood vessel tissue are determined. It is shown that deposition is dependent on surface charge. Moreover, the size dependency strongly suggests that nanoparticles are taken up by a passive mechanism that depends largely on geometry. These findings imply that it is possible to tune nanoparticle pharmacokinetics simply by adjusting nanoparticle size.     

IMing, Text Messaging, and Adolescent Social Networks

Building on previous research in computer-mediated communication, social and communication networks, and adolescent development, this article raises three issues regarding adolescent use of socially interactive technologies (SITs) and their relationship to offline social networks: 1) whether adolescents are creating more, but weaker ties using SITs, 2) to what extent adolescent SIT-facilitated networks overlap with friendship networks, and 3) whether SIT relationships are important for adolescents who have fewer offline peer ties. In order to investigate these questions, network data collection and analysis were integrated with more traditional questionnaire methodology and statistical analysis. The results show that the adolescents in the study were not creating more ties using SITs, nor were they necessarily creating weaker SIT-based ties; that there was little overlap between SIT-facilitated and offline social networks; and that socially isolated adolescents were less likely than other adolescents to use SITs.     

A stability study of green tea catechins during the biscuit making process

A green tea extract (GTE) was incorporated into biscuit as a source of tea catechins. The stability of tea catechins in the biscuit making process was studied. A method was developed for the separation and quantification of tea catechins in GTE, dough, and biscuit samples using a RP-HPLC system. GTEs at 150, 200, and 300 mg per 100 g of flour were formulated. The results obtained showed that green tea catechins were relatively stable in dough. The stability of (−)-EGCG and (−)-ECG was determined at an interval of every 2 min during baking. Their stability decreased as the baking progressed and increased as the concentration of GTE was increased in the biscuit dough. The stability of (−)-EGCG also increased as pH of the dough was reduced and made less alkaline.     

The Spatial Patterning of Alcohol Outlets in Post-Disaster Christchurch,New Zealand: Practical and Policy Implications

Natural disasters greatly impact the environment of affected societies with often unknown consequences. In this study we examine the impact that the Canterbury Earthquakes of 2010–2011 had on the distribution of alcohol outlets in Christchurch, New Zealand. Specifically, we compare the distribution of both on-site and off-site alcohol outlets pre- (December 2009) and post-earthquake (December 2014) and use spatial regression models to identify whether any neighbourhood-level factors predict the observed redistributions. Overall, the number of alcohol outlets decreased by almost 13% after the Canterbury Earthquakes. However, we found a moderate increase in the clustering of both outlet types of outlets in the post-quake period. Increases in rates of both on-site and off-site alcohol outlets in neighbourhoods were positively associated with the percentage of residents who resided in their neighbourhood < 5 years and with neighbourhood crime rate change, while negative associations were found with percentage population aged between 15 and 29 years. The results suggest that the changing spatial distribution of alcohol outlets in Christchurch was not random but driven, in part, by the emergent demographic composition of neighbourhoods. The significant practical and policy implications of a redistribution of alcohol outlets are outlined providing a tangible link between empirical research and practice in an urban environment plagued with post-disaster spatial and social uncertainties.     

Wavefront distortion of the reflected and diffracted beams produced by the thermoelastic deformation of a diffraction grating heated by a Gaussian laser beam

It may be advantageous in advanced gravitational-wave detectors to replace conventional beam splitters and Fabry-Perot input mirrors with diffractive elements. In each of these applications, the wavefront distortions produced by the absorption and subsequent heating of the grating can limit the maximum useful optical power. We present data on the wavefront distortions induced in a laser probe beam for both the reflected and diffracted beams from a grating that is heated by a Gaussian laser beam and compare these results to a simple theory of the wavefront distortions induced by thermoelastic deformations.     

Pathophysiology and Molecular Imaging of Diabetic Foot Infections

Diabetic foot infection is the leading cause of non-traumatic lower limb amputations worldwide. In addition, diabetes mellitus and sequela of the disease are increasing in prevalence. In 2017, 9.4% of Americans were diagnosed with diabetes mellitus (DM). The growing pervasiveness and financial implications of diabetic foot infection (DFI) indicate an acute need for improved clinical assessment and treatment. Complex pathophysiology and suboptimal specificity of current non-invasive imaging modalities have made diagnosis and treatment response challenging. Current anatomical and molecular clinical imaging strategies have mainly targeted the host’s immune responses rather than the unique metabolism of the invading microorganism. Advances in imaging have the potential to reduce the impact of these problems and improve the assessment of DFI, particularly in distinguishing infection of soft tissue alone from osteomyelitis (OM). This review presents a summary of the known pathophysiology of DFI, the molecular basis of current and emerging diagnostic imaging techniques, and the mechanistic links of these imaging techniques to the pathophysiology of diabetic foot infections.     

Chemical manipulation of glucose metabolism in porcine oocytes: effects on nuclear and cytoplasmic maturation in vitro

The objectives of this study were to manipulate metabolism of glucose through glycolysis and the pentose phosphate pathway (PPP) in porcine oocytes during in vitro maturation, and determine the effects of this manipulation on meiotic progression, intracellular glutathione (GSX) concentrations and embryonic development. Cumulus-oocyte complexes isolated from abattoir ovaries were matured (40-44 h) in Purdue Porcine Medium for maturation alone (control) or supplemented with pyrroline-5 carboxylate (PC, 0.1 microM; PPP stimulator), diphenyleneiodonium (DPI, 0.1 microM; PPP inhibitor), dinitrophenol (DNP, 10 microM; glycolytic stimulator), hexametaphosphate (HMP, 100 microM; glycolytic inhibitor), PC + HMP or DNP + DPI. At the conclusion of in vitro maturation, cumulus cells were removed and oocytes were randomly allocated for analysis of GSX, metabolism and nuclear maturation, or in vitro fertilization and embryo culture. Both DPI and DNP + DPI decreased (P < or = 0.05) the activity of glycolysis and the PPP, increased (P < or = 0.05) the percentage of immature oocytes, and decreased (P < or = 0.05) the proportion of mature oocytes compared with control oocytes and oocytes from the other treatments. Embryonic development (cleavage and blastocyst stage) and the intracellular content of GSX were also decreased (P < or = 0.05) following exposure to DPI or DNP + DPI compared with control oocytes and oocytes from the other treatments. Oocyte metabolism, nuclear maturation, GSX content and embryonic development were unaffected (P > 0.05) following exposure to PC, DNP, HMP or PC + HMP. Our results suggest that metabolism of glucose through the PPP and/or glycolysis plays a key role in the control of nuclear and cytoplasmic maturation of porcine oocytes in vitro.