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In‐field rapid and reliable identification of nerve agents is critical for the protection of Defence and National Security personnel as well as communities. Fluorescence‐based detectors can be portable and provide rapid detection of chemical threats. However, most current approaches cannot differentiate between dilute vapors of nerve agent classes and are susceptible to false positives due to the presence of common acids. Here a fluorescence‐based method is shown for rapid differentiation between the V‐series and phosphonofluoridate G‐series nerve agents and avoids false positives due to common acids. Differentiation is achieved through harnessing two different mechanisms. Detection of the V‐series is achieved using photoinduced hole transfer whereby the fluorescence of the sensing material is quenched in the presence of the V‐series agent. The G‐series is detected using a turn‐on mechanism in which a silylated excited state intramolecular proton transfer sensing molecule is selectively deprotected by hydrogen fluoride, which is typically found as a contaminant and/or breakdown product in G‐series agents such as sarin. The strategy provided discrimination between classes, as the sensor for the G‐series agent class is insensitive to the V‐series agent, and vice versa, and neither responded to common acids. [ABSTRACT FROM AUTHOR]

Fluorenylboronate ester chromophore-based thin films were investigated for the detection of triacetone triperoxide (TATP) vapors via the decomposition product, hydrogen peroxide. Sensing with a high level of sensitivity was achieved using a fluorescence "turn-on" mechanism based on the significant shifts in the absorption and photoluminescence spectra that occurs when the boronate esters were converted to phenoxides by hydrogen peroxide under basic conditions. The addition of an organic base was found to be critical for achieving fast conversion reactions and the formation of the phenoxide anions. Addition of a nitrile group to the fluorenyl boronate ester moiety improved the stability of the material to photooxidation, increased the photoluminescence quantum yields, and enhanced the absorption and emission shifts to longer wavelengths. In real-time sensing measurements, films comprising the cyanofluorenyl boronate ester moiety and tetra- n-butylammonium hydroxide had a response time to acid-decomposed TATP vapor of seconds and a limit of detection of 40 ppb in 60 s.

Objective: The aim of this study is to evaluate clinical data from a large cohort of acromegalic patients with and without hyperprolactinemia., Design and Methods: Between January 2002 and June 2010, a set of data on 279 acromegalic patients undergoing transsphenoidal surgery was available. Based on preoperative GH and prolactin (PRL) levels, patients were divided into GH and GH+PRL groups. A stabilization or a further improvement of postoperative changes in clinical, hormonal, immunohistochemical, and magnetic resonance imaging parameters was observed in all patients throughout the follow-up period., Results: The GH group had significantly more coarse facial features, large hands and feet, hypertension, and diabetes mellitus compared with the GH+PRL group but significantly less menstrual disorders (13.8 vs 54.3%, P<0.001) and galactorrhea (3.1 vs 22.4%, P<0.001). The GH group had a higher age at diagnosis compared with the GH+PRL group (45.6 ± 13.9 vs 40.4 ± 11.4 years, P=0.001). The GH group had a smaller mean maximal diameter of the adenomas (2.2 ± 0.9 vs 2.6 ± 1.1 cm, P=0.004). There were no significant correlations between hormone levels and the immunohistochemical results. According to the criteria for hormonal cure of acromegaly, the surgical control rates in the GH and GH+PRL groups were 68.4 and 59.7% respectively (P=0.187). Tumor size was an important factor that affected the results of the operations. The rates of surgical control in GH and GH+PRL groups were 80.7 and 69.1% respectively (P=0.037), and the recurrence rates in the two groups were 7.1 and 11.3% respectively (P=0.185)., Conclusions: Compared with patients with merely GH-secreting adenomas, acromegalic patients with hyperprolactinemia are characterized by an earlier onset of disease, lesser acromegalic features, lower GH levels, but larger tumor sizes, whereas in female patients, GH-PRL secreting adenomas are associated with higher incidences of menstrual disorders and galactorrhea.