Dense gas in nearby galaxies XVI. The nuclear starburst environment in NGC4945

A multi-line millimeter-wave study of the nearby starburst galaxy NGC 4945 has been carried out using the Swedish-ESO Submillimeter Telescope (SEST). The study covers the frequency range from 82 GHz to 354 GHz and includes 80 transitions of 19 molecules. 1.3 mm continuum data of the nuclear source are also presented. A large number of molecular species indicate the presence of a prominent high density interstellar gas component characterized by $n_{\rm H_2}\sim10^5$ cm$^{-3}$. Abundances of molecular species are calculated and compared with abundances observed toward the starburst galaxies NGC 253 and M 82 and galactic sources. Apparent is an `overabundance' of HNC in the nuclear environment of NGC 4945. While the HNC/HCN $J$=1--0 line intensity ratio is $\sim$0.5, the HNC/HCN abundance ratio is $\sim$1. While HCN is subthermally excited ($T_{\rm ex}\sim$8 K), CN is even less excited ($T_{\rm ex}\sim$3--4 K), indicating that it arises from a less dense gas component and that its $N$=2--1 line can be optically thin even though its $N$=1--0 emission is moderately optically thick. Overall, fractional abundances of NGC 4945 suggest that the starburst has reached a stage of evolution that is intermediate between those observed in NGC 253 and M 82. Carbon, nitrogen, oxygen and sulfur isotope ratios are also determined. Within the limits of uncertainty, carbon and oxygen isotope ratios appear to be the same in the nuclear regions of NGC 4945 and NGC 253. High $^{18}$O/$^{17}$O, low $^{16}$O/$^{18}$O and $^{14}$N/$^{15}$N and perhaps also low $^{32}$S/$^{34}$S ratios appear to be characteristic properties of a starburst environment in which massive stars have had sufficient time to affect the isotopic composition of the surrounding interstellar medium.Comment: 26 pages, 16 figures, accepted bt A&

Extracellular vesicle microRNA cargo is correlated with HPV status in oropharyngeal carcinoma

Background The incidence of human papilloma virus positive (HPV+) oropharyngeal squamous cell carcinoma (OPSCC) has increased rapidly in recent decades. These tumours have a favourable outcome compared to HPV‐negative (HPV−) OPSCC. However, HPV+ tumours are more likely to metastasise to distant sites, suggesting a difference in how these tumour subtypes interact with the metastatic niche. Extracellular vesicles (EVs) have emerged as important players in cell‐to‐cell communication and are a potential source of biomarkers for cancer diagnosis. This study aims to characterise the microRNA cargo of small EVs released by HPV+ and HPV− OPSCC cell lines. Methods Extracellular vesicles produced by HPV+ (SCC2 and SCC90) and HPV− (SCC72 an SCC89) OPSCC cells were characterised by tunable resistive pulse sensing (TRPS) and western blotting. RNA was extracted from EVs and analysed by small RNA sequencing. A bioinformatics approach was used to identify EV miRNA signatures associated with HPV status. Results HPV− OPSCC cells produced more EVs than HPV+ OPSCC cells. EVs were positive for the common EV markers CD63, CD9 and TSG101. Unbiased hierarchical clustering analysis of EV miRNA cargo revealed that samples clustered based on HPV status. 14 miRNA were enriched in HPV+ cell‐derived EVs, whereas 19 miRNA were enriched in EVs derived from HPV− cell lines. Conclusions Here, we identify EV miRNA signatures indicative of the HPV status of the parent cell. This may provide a platform from which to validate salivary or blood‐based biomarkers with utility for early detection and stratifying risk in OPSCC patients

Demographics of extra-articular calcaneal fractures: Including a review of the literature on treatment and outcome

Introduction: Extra-articular calcaneal fractures represent 25-40% of all calcaneal fractures and an even higher percentage of up to 60% is seen in children. A disproportionately small part of the literature on calcaneal fractures involves the extra-articular type. The aim of this study was to investigate the incidence of extra-articular calcaneal fractures in a Level 1 trauma centre, define the distribution of the various types of fractures and compare patient demographics between extra- and intra-articular calcaneal fractures. In addition the literature was reviewed for the most common types of extra-articular calcaneal fractures with regard to incidence, treatment and clinical outcome. Methods: The radiological records between 2003 and 2005 were reviewed for intra- and extra-articular calcaneal fractures. Patient gender-distribution and age were compared. A literature search was conducted for the treatment of extra-articular calcaneal fractures. Results: In this 3-year study period a total of 49 patients with 50 extra-articular calcaneal fractures and 91 patients with 101 intra-articular fractures were identified. The median age for the first group was 32.7 years, and for the second group 40.3 years; P = 0.04. Male predominance was significantly less pronounced for extra-articular (63%) compared with intra-articular fractures (79%; P = 0.04). Conclusion: One-third of all calcaneal fractures are extra-articular. Significant differences exist between the intra- and extra-articular groups, in terms of lower age and male-female ratio. The literature study shows inconsistencies in treatment options, but most extra-articular fractures are well manageable conservatively

Review of nanomaterials in dentistry: interactions with the oral microenvironment, clinical applications, hazards, and benefits.

Interest in the use of engineered nanomaterials (ENMs) as either nanomedicines or dental materials/devices in clinical dentistry is growing. This review aims to detail the ultrafine structure, chemical composition, and reactivity of dental tissues in the context of interactions with ENMs, including the saliva, pellicle layer, and oral biofilm; then describes the applications of ENMs in dentistry in context with beneficial clinical outcomes versus potential risks. The flow rate and quality of saliva are likely to influence the behavior of ENMs in the oral cavity, but how the protein corona formed on the ENMs will alter bioavailability, or interact with the structure and proteins of the pellicle layer, as well as microbes in the biofilm, remains unclear. The tooth enamel is a dense crystalline structure that is likely to act as a barrier to ENM penetration, but underlying dentinal tubules are not. Consequently, ENMs may be used to strengthen dentine or regenerate pulp tissue. ENMs have dental applications as antibacterials for infection control, as nanofillers to improve the mechanical and bioactive properties of restoration materials, and as novel coatings on dental implants. Dentifrices and some related personal care products are already available for oral health applications. Overall, the clinical benefits generally outweigh the hazards of using ENMs in the oral cavity, and the latter should not prevent the responsible innovation of nanotechnology in dentistry. However, the clinical safety regulations for dental materials have not been specifically updated for ENMs, and some guidance on occupational health for practitioners is also needed. Knowledge gaps for future research include the formation of protein corona in the oral cavity, ENM diffusion through clinically relevant biofilms, and mechanistic investigations on how ENMs strengthen the tooth structure

Deciphering Proteomic Signatures of Early Diapause in Nasonia

Insect diapause is an alternative life-history strategy used to increase longevity and survival in harsh environmental conditions. Even though some aspects of diapause are well investigated, broader scale studies that elucidate the global metabolic adjustments required for this remarkable trait, are rare. In order to better understand the metabolic changes during early insect diapause, we used a shotgun proteomics approach on early diapausing and non-diapausing larvae of the recently sequenced hymenopteran model organism Nasonia vitripennis. Our results deliver insights into the molecular underpinnings of diapause in Nasonia and corroborate previously reported diapause-associated features for invertebrates, such as a diapause-dependent abundance change for heat shock and storage proteins. Furthermore, we observed a diapause-dependent switch in enzymes involved in glycerol synthesis and a vastly changed capacity for protein synthesis and degradation. The abundance of structural proteins and proteins involved in protein synthesis decreased with increasing diapause duration, while the abundance of proteins likely involved in diapause maintenance (e.g. ferritins) increased. Only few potentially diapause-specific proteins were identified suggesting that diapause in Nasonia relies to a large extent on a modulation of pre-existing pathways. Studying a diapause syndrome on a proteomic level rather than isolated pathways or physiological networks, has proven to be an efficient and successful avenue to understand molecular mechanisms involved in diapause