Health-related quality of life in patients with T1N0 oral squamous cell carcinoma: selective neck dissection compared with wait and watch surveillance

Management of the neck in patients with clinical T1N0 oral squamous cell carcinoma (SCC) is controversial. The aim of this study was to report the health-related quality of life (HRQoL) in a consecutive group of patients with stage 1 disease at a time closest to two years after primary surgery. Of 216 patients treated between 2007 and 2012 (after excluding early death and regional recurrence), 195 were eligible. HRQoL was measured using the University of Washington quality of life questionnaire version 4. The overall response rate was 65% (126/195). HRQoL outcomes were good, but compared with patients in the wait and watch group, those who had selective neck dissection (SND) had more problems regarding appearance (14% compared with 1%, p = 0.008) and pain (19% compared with 6%, p = 0.04). Similar trends were seen for shoulder (14% compared with 8%), mood (16% compared with 8%), and speech (5% compared with 1%), and for poorer overall QoL (30% compared with 16%). It is difficult to establish why patients did or did not have neck dissection in a retrospective sample, but it is likely that those who had SND had larger tumours. The findings highlight the impact that SND has on HRQoL in domains such as appearance, pain, speech, swallowing, and chewing. Previous studies on SND have tended to focus on injury to the accessory nerve and shoulder function, but these new data emphasise the need to include other domains in future trials that compare wait and watch, SND, and sentinel lymph node biopsy

Reversible suppression of an essential gene in adult mice using transgenic RNA interference

RNAi has revolutionized loss-of-function genetics by enabling sequence-specific suppression of virtually any gene. Furthermore, tetracycline response elements (TRE) can drive expression of short hairpin RNAs (shRNAs) for inducible and reversible target gene suppression. Here, we demonstrate the feasibility of transgenic inducible RNAi for suppression of essential genes. We set out to directly target cell proliferation by screening an RNAi library against DNA replication factors and identified multiple shRNAs against Replication Protein A, subunit 3 (RPA3). We generated transgenic mice with TRE-driven Rpa3 shRNAs whose expression enforced a reversible cell cycle arrest. In adult mice, the block in cell proliferation caused rapid atrophy of the intestinal epithelium which led to weight loss and lethality within 8-11 d of shRNA induction. Upon shRNA withdrawal, villus atrophy and weight loss were fully reversible. Thus, shRpa3 transgenic mice provide an interesting tool to study tissue maintenance and regeneration. Overall, we have established a robust system that serves the purpose of temperature-sensitive alleles in other model organisms, enabling inducible and reversible suppression of essential genes in a mammalian system

On wealth and the diversity of friendships: high social class people around the world have fewer international friends

Having international social ties carries many potential advantages, including access to novel ideas and greater commercial opportunities. Yet little is known about who forms more international friendships. Here, we propose social class plays a key role in determining people's internationalism. We conducted two studies to test whether social class is related positively to internationalism (the building social class hypothesis) or negatively to internationalism (the restricting social class hypothesis). In Study 1, we found that among individuals in the United States, social class was negatively related to percentage of friends on Facebook that are outside the United States. In Study 2, we extended these findings to the global level by analyzing country-level data on Facebook friends formed in 2011 (nearly 50 billion friendships) across 187 countries. We found that people from higher social class countries (as indexed by GDP per capita) had lower levels of internationalism—that is, they made more friendships domestically than abroad

Tracing H2 column density with atomic carbon (CI) and CO isotopologues

We present first results of neutral carbon ([CI], 3P1 - 3P0 at 492 GHz) and carbon monoxide (13CO, J = 1 - 0) mapping in the Vela Molecular Ridge cloud C (VMR-C) and G333 giant molecular cloud complexes with the NANTEN2 and Mopra telescopes. For the four regions mapped in this work, we find that [CI] has very similar spectral emission profiles to 13CO, with comparable line widths. We find that [CI] has opacity of 0.1 - 1.3 across the mapped region while the [CI]/13CO peak brightness temperature ratio is between 0.2 to 0.8. The [CI] column density is an order of magnitude lower than that of 13CO. The H2 column density derived from [CI] is comparable to values obtained from 12CO. Our maps show CI is preferentially detected in gas with low temperatures (below 20 K), which possibly explains the comparable H2 column density calculated from both tracers (both CI and 12CO underestimate column density), as a significant amount of the CI in the warmer gas is likely in the higher energy state transition ([CI], 3P2 - 3P1 at 810 GHz), and thus it is likely that observations of both the above [CI] transitions are needed in order to recover the total H2 column density.Comment: accepted for publication in ApJ Letter