Initiatives for Early Medical Student Engagement with the Field of Otolaryngology - Head and Neck Surgery.

OBJECTIVE: Early exposure and mentorship in surgical specialties like otolaryngology - head and neck surgery are critical for medical students. This paper presents initiatives implemented at our institution to engage early-career medical students with the field. METHODS: A hands-on laryngoscope workshop was organised, and a centralised online platform was created for research and mentorship opportunities using a collaborative project management tool. Both measures were advertised via e-mail to student interest groups and campus diversity groups. At the end of the workshop, participating students completed an online distributed survey. RESULTS: Students' perception of their knowledge of airway anatomy and related clinical scenarios significantly improved after the laryngoscopy workshop (p = 0.001 and p = 0.002, respectively). All attendees indicated that the workshop increased their comfort level with procedures and that they would recommend the workshop to colleagues. Nearly half of participants reported becoming 'very interested' in exploring otolaryngology - head and neck surgery through future elective courses. CONCLUSION: Implementation of such initiatives at other institutions can generate medical student interest and may improve diversity in otolaryngology - head and neck surgery.

Live-streaming otolaryngology surgical procedures for virtual medical student rotations.

BACKGROUND: The coronavirus disease 2019 pandemic created challenges in surgical education that expedited the development of virtual learning. Virtual rotations have been one such solution. However, they require co-ordination and technological equipment to create a meaningful, interactive experience for students. METHODS: Various otolaryngology surgical procedures were live-streamed during a two-week virtual rotation for medical students. A mobile audiovisual cart comprising a computer mounted with a webcam and microphone/speaker were utilised to live-stream from four sources: video-assisted telescope operating monitor ('VITOM') exoscope, microscope, endoscope and room camera. A dedicated faculty member, who was not the operating surgeon, was present to facilitate students' understanding of the procedure. CONCLUSION: A wide breadth of otolaryngology surgical procedures were live-streamed via a mobile audiovisual computer, including views of the room, endoscopic views, microscopic views and open views via an exoscope (video-assisted telescope operating monitor). This virtual rotation set-up, along with the dedicated faculty facilitator, reduced the burden on the operating surgeon and enhanced students' learning experience.

Efficacy of 3,5-dibromo-L-phenylalanine in rat models of stroke, seizures and sensorimotor gating deficit.

BACKGROUND AND PURPOSE: Abnormal glutamatergic activity is implicated in neurologic and neuropsychiatric disorders. Selective glutamate receptor antagonists were highly effective in animal models of stroke and seizures but failed in further clinical development because of serious side effects, including an almost complete set of symptoms of schizophrenia. Therefore, the novel polyvalent glutamatergic agent 3,5-dibromo-L-phenylalanine (3,5-DBr-L-Phe) was studied in rat models of stroke, seizures and sensorimotor gating deficit. EXPERIMENTAL APPROACH: 3,5-DBr-L-Phe was administered intraperitoneally as three boluses after intracerebral injection of endothelin-1 (ET-1) adjacent to the middle cerebral artery to cause brain injury (a model of stroke). 3,5-DBr-L-Phe was also given as a single bolus prior to pentylenetetrazole (PTZ) injection to induce seizures or prior to the administration of the N-methyl-D-aspartate (NMDA) receptor antagonist dizocilpine (MK-801) to cause disruption of prepulse inhibition (PPI) of startle (sensorimotor gating deficit). KEY RESULTS: Brain damage caused by ET-1 was reduced by 52%, which is comparable with the effects of MK-801 in this model as reported by others. 3,5-DBr-L-Phe significantly reduced seizures induced by PTZ without the significant effects on arterial blood pressure and heart rate normally caused by NMDA antagonists. 3,5-DBr-L-Phe prevented the disruption of PPI measured 3 days after the administration of ET-1. 3,5-DBr-L-Phe also eliminated sensorimotor gating deficit caused by MK-801. CONCLUSION AND IMPLICATIONS: The pharmacological profile of 3,5-DBr-L-Phe might be beneficial not only for developing a therapy for the neurological and cognitive symptoms of stroke and seizures but also for some neuropsychiatric disorders.

Electrochemiluminescence detection for development of immunoassays and DNA probe assays for clinical diagnostics.

Electrochemiluminescence (ECL) has been developed as a highly sensitive process in which reactive species are generated from stable precursors (i.e., the ECL-active label) at the surface of an electrode. This new technology has many distinct advantages over other detection systems: no radioisotopes are used; detection limits for label are extremely low (200 fmol/L); the dynamic range for label quantification extends over six orders of magnitude; the labels are extremely stable compared with those of most other chemiluminescent systems; the labels, small molecules (approximately 1000 Da), can be used to label haptens or large molecules, and multiple labels can be coupled to proteins or oligonucleotides without affecting immunoreactivity, solubility, or ability to hybridize; because the chemiluminescence is initiated electrochemically, selectivity of bound and unbound fractions can be based on the ability of labeled species to access the electrode surface, so that both separation and nonseparation assays can be set up; and measurement is simple and rapid, requiring only a few seconds. We illustrate ECL in nonseparation immunoassays for digoxin and thyrotropin and in separation immunoassays for carcinoembryonic antigen and alpha-fetoprotein. The application of ECL for detection of polymerase chain reaction products is described and exemplified by quantifying the HIV1 gag gene.

Fluoroenzymatic cycling assay (FECA) for the determination of catechol estrogen monomethyl ethers in human urine.

In the present study a method is described for the quantitative determination of the methylated metabolites of catechol estrogens in human urine. Following initial enzymatic hydrolysis the urine samples are extracted with ethyl acetate. The monomethyl ethers of catechol estrogens are then selectively fractionated with straight phase chromatography on Lipidex-5000 gel. Finally, samples are quantitated using enzymatic cycling with 17 beta-estradiol dehydrogenase combined with fluorometry. The method is sensitive, reproducible and reasonably rapid for routine analysis and avoids the hazards of radioisotopes. Preliminary values of normal males and non-pregnant females are presented.

Penicillinase as a marker in enzyme-linked immunosorbent assays for steroid hormones.

Using penicillinase (E.C. 3.5.2.6) as marker and microtitre ELISA plates for immunoadsorption, sensitive and specific assays for two steroid hormones viz. testosterone in plasma and estrone-3-glucuronide in urine were developed. The entire assay can be performed in 4 h and requires simple laboratory equipment such as an incubator and a colorimeter. The enzyme labelled steroids have a shelf life of more than 3 years.

A simple, rapid and reliable enzyme-linked immunosorbent assay (ELISA) for measuring estrone-3-glucuronide in urine.

A rapid, simple and sensitive enzyme-linked immunosorbent assay for the estimation of estrone-3-glucuronide (E1G) in diluted unprocessed urine has been developed using E1G-penicillinase (E.C.3.5.2.6.) prepared via carbodiimide linkage. Polyvinyl chloride ELISA plate (Dynatech) coated with antibody was used for separation of the antibody bound ligand. A complete assay could be performed within 4 hours with good precision (C.V. less than 17%). Minimum detectable amount of E1G was 25 pg/well. Parallelism was observed between sample dilution curve and standard curve. Recovery of E1G from urine ranged between 85-105%. Results obtained on 29 urine samples by the ELISA procedure were comparable to those obtained with an established RIA procedure (r = 0.96). The present method may thus provide a useful tool for the assessment of ovarian function.

A simple and sensitive color test for the detection of human chorionic gonadotropin.

A simple, rapid, sensitive, and reliable ELISA test for the detection of urinary human chorionic gonadotropin (hCG) has been developed using penicillinase (EC no. 3.5.2.6) as the label and a microtiter ELISA plate as a solid support for antibody. The results of the test is assessed visually for the dark blue that indicates the presence of hCG. A minimum of 500 mU of hCG/ml of urine can be detected easily and the test can be completed in 2 hours with good precision. Accurate negative results are obtained in urine samples of normally ovulatory women, postmenopausal women, and adult males, suggesting that the physiologic concentrations of luteinizing hormone do not influence the assay results. In samples referred for pregnancy detection 95.5% accurate results were obtained when compared with histopathologic and/or clinical findings. There were 2 false-negative results, and only in 4 of 132 subjects studied were false-positive results obtained. This test, if properly performed, should prove a valuable tool in the detection of hCG as early as 30 to 35 days from the last menstrual period.

A sensitive and specific enzymeimmunoassay for serum testosterone.

A very sensitive enzymeimmunoassay for testosterone was developed using testosterone-penicillinase conjugate and an antibody to testosterone-3-(O-carboxymethyl)oxime-bovine serum albumin. The specificity of the assay was demonstrated by the fact that estradiol-17 beta, estrone, estriol, progesterone, 17 alpha-hydroxy-progesterone, dehydroepiandrosterone, androstenedione, cortisol and cortisone were ineffective in crossreacting with testosterone while dihydrotestosterone was 8 times less crossreactive as compared to testosterone. The minimum detectable amount of testosterone was 10-15 pg per assay tube. Intra-assay and inter-assay coefficients of variation for samples containing 0.3-6ng/ml of testosterone were 6-8% and 8-10%, respectively. A high degree of correlation (r = 0.97) was observed between serum testosterone values obtained by enzymeimmunoassay and radioimmunoassay. The levels of testosterone in the sera of normal men and women and those in hypogonadal males following stimulation with human chorionic gonadotropin determined by this enzymeimmunoassay appear similar to those reported by other investigators.