A user evaluation of speech/phrase recognition software in critically ill patients: a DECIDE-AI feasibility study

OBJECTIVES

Evaluating effectiveness of speech/phrase recognition software in critically ill patients with speech impairments.

DESIGN

Prospective study.

SETTING

Tertiary hospital critical care unit in the northwest of England.

PARTICIPANTS

14 patients with tracheostomies, 3 female and 11 male.

MAIN OUTCOME MEASURES

Evaluation of dynamic time warping (DTW) and deep neural networks (DNN) methods in a speech/phrase recognition application. Using speech/phrase recognition app for voice impaired (SRAVI), patients attempted mouthing various supported phrases with recordings evaluated by both DNN and DTW processing methods. Then, a trio of potential recognition phrases was displayed on the screen, ranked from first to third in order of likelihood.

RESULTS

A total of 616 patient recordings were taken with 516 phrase identifiable recordings. The overall results revealed a total recognition accuracy across all three ranks of 86% using the DNN method. The rank 1 recognition accuracy of the DNN method was 75%. The DTW method had a total recognition accuracy of 74%, with a rank 1 accuracy of 48%.

CONCLUSION

This feasibility evaluation of a novel speech/phrase recognition app using SRAVI demonstrated a good correlation between spoken phrases and app recognition. This suggests that speech/phrase recognition technology could be a therapeutic option to bridge the gap in communication in critically ill patients.

WHAT IS ALREADY KNOWN ABOUT THIS TOPIC

Communication can be attempted using visual charts, eye gaze boards, alphabet boards, speech/phrase reading, gestures and speaking valves in critically ill patients with speech impairments.

WHAT THIS STUDY ADDS

Deep neural networks and dynamic time warping methods can be used to analyse lip movements and identify intended phrases.

HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE AND POLICY

Our study shows that speech/phrase recognition software has a role to play in bridging the communication gap in speech impairment.

Large-scale synthesis of peptides

Recent advances in the areas of formulation and delivery have rekindled the interest of the pharmaceutical community in peptides as drug candidates, which, in turn, has provided a challenge to the peptide industry to develop efficient methods for the manufacture of relatively complex peptides on scales of up to metric tons per year. This article focuses on chemical synthesis approaches for peptides, and presents an overview of the methods available and in use currently, together with a discussion of scale-up strategies. Examples of the different methods are discussed, together with solutions to some specific problems encountered during scale-up development. Finally, an overview is presented of issues common to all manufacturing methods, i.e., methods used for the large-scale purification and isolation of final bulk products and regulatory considerations to be addressed during scale-up of processes to commercial levels.

Conjugates of catecholamines. VII. Synthesis and beta-adrenergic activity of peptide catecholamine conjugates

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Inhibition of the Activities of α2-Plasmin inhibitor (PI) and CI inhibitor (CI-Inh) by the Synthetic Fibrinolytic Agent, 3-Hydroxypropyl Flufenamide (Flu-HPA)

Flu-HPA is one of a series of flufenamic acid derivations that enhances plasminogen-dependent clot lysis in vitro. Studies of possible mechanisms of action of Flu-HPA were undertaken. The influence of Flu-HPA on the inhibition of purified plasmin by purified PI was studied. PI activity was assessed by its inhibition of the clevage of the tripeptide S-2251 (H-D-Val-Leu-Lys-pNA) by plasmin. Flu-HPA was dissolved in DMF or in methonol and preincubated with PI before addition of plasmin. At Flu-HPA concentrations greater than 1mM and up to 60mM, the inhibitory activity of PI was totally lost. The inhibitory effect of normal human plasma on plasmin was also completely abolished at concentrations of Flu-HPA between 2.5 and 40mM. The effect of Flu-HPA on the inhibition of purified plasma kallikrein by purified CI-Inh was also studied. CI-Inh activity was measured by its inhibition of cleavage of the tripeptide Bz-Pro-Phe-Arg-pNA by kallikrein. When Flu-HPA, dissolved in DMF or in methonol, was preincubated with CI-Inh, a concentration dependent inhibition of CI-Inh activity was observed. CI-Inh activity was abolished by concentrations of Flu-HPA greater than 1mM. Flu-HPA also inhibited the activity of CI-Inh on purified Factor XIIa. These observations suggest that this flufenamic acid derivative may enhance fibrinolysis not only by inhibiting PI activity but also by decreasing the inactivation of plasminogen activators by CI-Inh.

Inhibition of the Activities of α2-Plasmin Inhibitor (PI) and CĪ Inhibitor (CĪ-Inh by the Synthetic Fibrinolytic Agent, 3-Hydroxypropyl Flufenamide (Flu-HPA)

Flu-HPA is one of a series of flufenamic acid derivatives that enhances plasminogen-de-pendent clot lysis in vitro. Studies of possible mechanisms of action of Flu-HPA were undertaken. The influence of Flu-HPA on the inhibition of purified plasmin by purified PI was studied. PI activity was assessed by its inhibition of the cleavage of the tripeptide S-2251(H-D-Val-Leu-Lys-pNA) by plasmin. Flu-HPA was dissolved in DMF or in n-ethanol and preincubated with PI before addition of plasmin. At FIu-HPA concentrations greater than ImM and up to 60mM, the inhibitory activity of PI was totally lost. The inhibitory effect of normal human plasma on plasmin was also completely abolished at concentrations of Flu-HPA between 2.5 and 40mM. The effect of Flu-HPA on the inhibition of purified plasma kallikrein by purified CĪ-Inh was also studied. CĪ-Inh activity was measured by its inhibition of cleavage of the tripeptide Bz-Pro-Phe-Arg-pNA by kallikrein. When FIu-HPA, dissolved in DMF or in methanol, was preincubated with CĪ-lnh, a concentration dependent inhibition of CĪ-Inh activity was observed. CĪ-Inh activity was abolished by concentrations of Flu-HPA greater than ImM. Flu-HPA also inhibited the activity of CĪ-Inh on purified Factor XIIa. These observations suggest that this flufenamic acid derivative may enhance fibrinolysis not only by inhabiting PI activity but also by decreasing the inactivation of plasminogen activators by CĪ-Inh.