Donal O’Shea

Azide Conjugatable and pH Responsive Near-Infrared Fluorescent Imaging Probes

The synthesis and photophysical characteristics of a pH responsive near-infrared fluorescence imaging probe is described. A key feature is the ability to conjugate the probe by an alkyne-azide cycloaddition reaction and its reversible response of fluorescence intensity across the physiological pH range.

New on-bead near-infrared fluorophores and fluorescent sensor constructs.

The facile synthesis and photophysical characterization of new on-bead fluorophores and fluorescent sensors are described. The unique covalent immobilization strategy results in highly fluorescent beads with sharp emission profiles between 650 and 800 nm. Illustrative examples include imaging in an aqueous cellular environment and adaptation to include off/on sensing functionality, proven by a prototypical detection of gaseous HCl.

The Omentum: Anatomical, Metabolic, and Surgical Aspects

IntroductionThe omentum is acknowledged to have diverse functions in the pathophysiology of intra-abdominal disease. Its angiogenic properties act as a natural defense mechanism in peritonitis and intra-abdominal sepsis. With advancing technology the omentum is revealing itself as a new player in the field of molecular surgery with special reference to cancer, obesity and tissue reconstruction.Materials and methodsThis article reviews the existing and potential surgical applications of the omentum.

A substituted BF2-chelated tetraarylazadipyrromethene as an intrinsic dual chemosensor in the 650–850 nm spectral range

The synthesis and spectral analysis of a new class of long wavelength intrinsic fluorosensor is reported. Chemosensor performance reveals large off/on fluorescence intensity responses to acid analyte with low response to microenvironment polarity. Application to ratiometric fluorescence/UV-visible analysis is outlined.

Controlled anion migrations with a mixed metal Li/K-TMP amide: general application to benzylic metalations.

A general method is described for benzylic metalation of o-, m-, and p-substituted toluenes using a mixed metal amide base generated from BuLi/KOtBu/TMP at -78 °C in THF. The excellent selectivity achieved can be rationalized by the ability of the mixed metal amide base to facilitate an anion migration from the kinetic (o-aryl) to the benzylic metalation site. Remarkably, this controlled anion migration is achievable with catalytic amounts of TMP at -78 °C.

Mechanistic insight into the formation of tetraarylazadipyrromethenes.

The tetraarylazadipyrromethene chromophore class has gained increasing attention in the past decade for a diverse set of scientific interests and applications. The most direct synthetic route available for their generation is heating of 4-nitro-1,3-diarylbutan-1-ones with an ammonium source in an alcohol solvent. Despite the practical simplicity, the reaction pathway(s) for these conversions are lengthy and unclear. To gain insight into the steps involved, (15)N labeling experiments with MS and NMR analysis were utilized for conversion of 4-nitro-1,3-diphenylbutan-1-one 1 into tetraphenylazadipyrromethene 2 with (15)NH(4)OAc. To permit examination of later stages of the reaction sequence to 2, the (15)N-labeled potential intermediate 3,5-diphenyl-1H-pyrrol-2-amine 10 was synthesized. A study of the dimerization pathway utilizing (15)N-labeled 10 revealed an unprecedented nitrogen rearrangement in the final stages of the pathway involving a ring-opening/closing of a pyrrole ring. Utilizing (15)N labeling experiments we have shown that 2,4-diphenylpyrrole 8 can also react under the reaction conditions with 3,5-diphenyl-2H-pyrrol-2-imine 7 (from oxidation of 10) to produce 2. Overall in the conversion of 1 into 2, two related pathways are ongoing concurrently; the first involves a dimerization of 3,5-diphenyl-2H-pyrrol-2-imine 7, and the other a reaction of 7 with 2,4-diphenylpyrrole 8.

Selective Vinyl C−H Lithiation of cis-Stilbenes

A stereochemistry-controlled suppression of carbolithiation facilitated a regioselective vinyl C-H lithiation of cis-stilbenes allowing routine regio- and stereoselective access to polysubstituted alkenes and heterocycles. This unique selectivity was obtained for numerous directing groups and could be rationalized with DFT computational studies and an experimental mechanistic illustration of a unique anion migration.

Adipose Type One Innate Lymphoid Cells Regulate Macrophage Homeostasis through Targeted Cytotoxicity

SUMMARY Adipose tissue has a dynamic immune system that adapts to changes in diet and maintains homeostatic tissue remodeling. Adipose type 1 innate lymphoid cells (AT1‐ILCs) promote pro‐inflammatory macrophages in obesity, but little is known about their functions at steady state. Here we found that human and murine adipose tissue harbor heterogeneous populations of AT1‐ILCs. Experiments using parabiotic mice fed a high‐fat diet (HFD) showed differential trafficking of AT1‐ILCs, particularly in response to short‐ and long‐term HFD and diet restriction. At steady state, AT1‐ILCs displayed cytotoxic activity toward adipose tissue macrophages (ATMs). Depletion of AT1‐ILCs and perforin deficiency resulted in alterations in the ratio of inflammatory to anti‐inflammatory ATMs, and adoptive transfer of AT1‐ILCs exacerbated metabolic disorder. Diet‐induced obesity impaired AT1‐ILC killing ability. Our findings reveal a role for AT1‐ILCs in regulating ATM homeostasis through cytotoxicity and suggest that this function is relevant in both homeostasis and metabolic disease. Graphical Abstract Figure. No Caption available. HighlightsAT1‐ILCs are enriched in mouse and human adipose tissue and are predominantly tissue residentAT1‐ILCs kill adipose tissue macrophages (ATMs) and maintain ATM homeostasisSubsets of AT1‐ILCs infiltrate adipose tissue during the onset of obesityIn obesity, AT1‐ILCs are reduced and lose their ability to kill &NA; Boulenouar et al. define different subsets of type 1 innate lymphoid cells (AT1‐ILCs) in human and murine adipose tissues and show that at steady state, AT1‐ILCs kill adipose tissue macrophages (ATMs). In obesity, cytotoxicity is impaired. Interference with AT1‐ILC cytotoxicity impacted ATM homeostasis and systemic metabolism, pointing to its importance in homeostasis and disease.

Radiofrequency Ablation for Neuroendocrine Liver Metastases: A Systematic Review

To determine the efficacy of radiofrequency (RF) ablation in neuroendocrine tumor (NET) liver metastases. A systematic review was performed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Eight studies were included (N = 301). Twenty-six percent of RF ablation procedures were percutaneous (n = 156), with the remainder conducted at surgery. Forty-eight percent of patients had a concomitant liver resection. Fifty-four percent of patients presented with symptoms, with 92% reporting symptom improvement following RF ablation (alone or in combination with surgery). The median duration of symptom improvement was 14-27 months. However, recurrence was common (63%-87%). RF ablation can provide symptomatic relief in NET liver metastases alone or in combination with surgery.

Gender Dysphoria – Prevalence and Co-Morbidities in an Irish Adult Population

Introduction: Gender dysphoria (GD) is a condition in which there is a marked incongruence between an individual’s psychological perception of his/her sex and their biological phenotype. Gender identity disorder was officially renamed “gender dysphoria” in the DSM-V in 2013. The prevalence and demographics of GD vary according to geographical location and has not been well-documented in Ireland. Methods: We retrospectively reviewed medical records of 218 patients with suspected or confirmed GD referred to our endocrine service for consideration of hormonal therapy (HT) between 2005 and early 2014. We documented their demographics, clinical characteristics, and treatment during the study period. Results: The prevalence of GD in the Irish population was 1:10,154 male-to-female (MTF) and 1:27,668 female-to-male (FTM), similar to reported figures in Western Europe. 159 of the patients were MTF and 59 were FTM, accounting for 72.9% and 27.1% of the cohort, respectively. The rate of referral has increased year-on-year, with 55 patients referred in 2013 versus 6 in 2005. Mean ages were 32.6 years (MTF) and 32.2 years (FTM). 22 of the patients were married and 41 had children, with 2 others having pregnant partners. 37.6% were referred by a psychologist, with the remainder evenly divided between GPs and psychiatric services. There were low rates of coexistent medical illness although psychiatric conditions were more prevalent, depression being a factor in 34.4% of patients. 5.9% of patients did not attend a mental health professional. 74.3% are currently on HT, and 9.17% have had gender reassignment surgery (GRS). Regret following hormonal or surgical treatment was in line with other Western European countries (1.83%). Conclusion: The incidence of diagnosis and referral of GD in Ireland is increasing. This brings with it multiple social, health, and financial implications. Clear and accessible treatment pathways supported by mental health professionals is essential.