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With continuing advancements in software, electronics, and miniaturization, ultrasound (US) is quickly becoming an everyday tool of numerous medical specialties. With the advent of new handheld and other small-scale units, physicians have a tool to obtain on demand imaging without exposing the patient to ionizing radiation in the pocket of their white coat. As such, the need for competency in US is increasing. Currently, US training primarily occurs in residency, with only a handful of institutions incorporating US into the undergraduate medical education (UME) curriculum. To date, no ideal method has been presented (Amini et al., Intern Emerg Med. 10(5):613-8, 2015; Wilson et al., J Ultrasound Med. 36(2):321-5, 2017). Presented herein is a method for the addition of US training into the undergraduate medical curriculum. Utilizing a co-enrolled course format, 6 medical students were given basic training in the history and physics of US, echocardiography (ECHO), right upper quadrant (RUQ) ultrasound, focused assessment with sonography for trauma (FAST), and extended (eFAST) exams, vascular access techniques, and MSK ultrasound over 17 sessions. Students theoretical knowledge was assessed during team-based learning (TBL) sessions in an individual and group readiness assurance test (IRAT/GRAT) format. Students' practical skill was assessed in an objective structured clinical examination (OSCE) format. Students demonstrated notable proficiency with the US unit and were able to conduct both US-guided peripheral and central vascular access techniques. Furthermore, students were able to identify 80% or more of the required structures for the RUQ, ECHO, and eFAST US exams.

We describe the curriculum of a 1-week ultrasound course for second-year medical students integrating didactics, bedside scanning, high-fidelity simulators, and a “Sonolympics” and evaluate its effectiveness. All students’ subjective confidence in using and interpreting ultrasound significantly increased, and students obtained and correctly interpreted ultrasound images in 86% of simulated cases.

Circadian misalignment between sleep and behavioral/feeding rhythms is thought to lead to various health impairments in shift workers. Therefore, we investigated how shift work leads to genome-wide circadian dysregulation in hospital nurses. Female nurses from the University of Alabama at Birmingham (UAB) Hospital working night shift ( n = 9; 29.6 ± 11.4 y) and day shift ( n = 8; 34.9 ± 9.4 y) participated in a 9-day study measuring locomotor activity and core body temperature (CBT) continuously. Additionally, cortisol and melatonin were assayed and peripheral blood mononuclear cells (PBMCs) were harvested for RNA extraction every 3 h on a day off from work. We saw phase desynchrony of core body temperature, peak cortisol, and dim light melatonin onset in individual night-shift subjects compared with day-shift subjects. This variability was evident even though day- and night-shift nurses had similar sleep timing and scheduled meal times on days off. Surprisingly, the phase and rhythmicity of the expression of the clock gene, PER1, in PBMCs were similar for day-shift and night-shift subjects. Genome-wide microarray analysis of PBMCs from a subset of nurses revealed distinct gene expression patterns between night-shift and day-shift subjects. Enrichment analysis showed that day-shift subjects expressed pathways involved in generic transcription and regulation of signal transduction, whereas night-shift subjects expressed pathways such as RNA polymerase I promoter opening, the matrisome, and endocytosis. In addition, there was large variability in the number of rhythmic transcripts among subjects, regardless of shift type. Interestingly, the amplitude of the CBT rhythm appeared to be more consistent with the number of cycling transcripts for each of the 6 subjects than was melatonin rhythm. In summary, we show that shift-work patterns affect circadian alignment and gene expression in PBMCs.

Cost limitations of commercial-grade ultrasound phantoms often prevent ultrasound education from being incorporated into medical curricula (Bahner et al., Acad Med. 89:1681–6, 2014). While production of homemade agar gelatin phantoms to offset costs has been well documented, use of ballistic gelatin has only recently been described (Domenico et al., J Ultrasound. 11 (4):135-42, 2008; Zerth et al., J Emerg Med. 43:1066-9, 2012; Chao et al., J Emerg Med. 45:240-3, 2013; Shobeiri et al., J Ultrasound Med. 32:1393-6, 2013; Woywodt et al., Clin Nephrol. 79:241-5, 2013; Zeiler et al., Can J Neurol Sci. 40:225-9, 2013; Hunt et al., Eur J Radiol. 82:594-600, 2013; Lo et al., Emerg Med J. 29:738-41, 2012; Li et al., J Ultrasound Med. 30:263-72, 2011; Morrow and Broder, J Emerg Med. 49 (3):313-7, 2015). There exists a critical need for learner evaluation of homemade ballistic gelatin phantoms (BGPs) and their comparison to commercial-grade phantoms to better inform BGP introduction into medical education. The primary aim of this study is to describe survey-based evaluation of homemade BGPs and commercial-grade Blue PhantomsTM by medical students. The secondary aim is to compare image quality of BGPs and Blue PhantomsTM. Described are construction of BGPs and introduction in voluntary ultrasound training sessions offered to 61 first through fourth-year medical students. The evaluation and success of this model are reported. Students reported that versatility of homemade BGPs surpassed that of commercially available phantoms (4.52 ± 0.71) and that they felt more confident in their ultrasound skills after the session (4.82 ± 0.37). Side-by-side evaluation of images generated using BGPs and Blue PhantomsTM had comparable simulated vessel shape and echogenicity, adding objective assessment to subjective survey-based results. Training sessions were enabled by low-cost homemade BGPs at $4 vs $400+ cost of commercial-grade phantoms, a 100-fold reduction in cost. As students found BGPs and Blue PhantomsTM comparable, the results of this study can equip other institutions struggling with costs of incorporating ultrasound into their medical curricula with not only a cost-effective solution but also a learner-validated one.

The study of human anatomy has long been one of the cornerstones of medical training and practice. However, the need to teach other preclinical subjects in more depth within modern medical curricula has led to increasingly fewer hours being dedicated to anatomy. With limited time and few qualified instructors, the ability to convey fundamental anatomical knowledge and understanding to medical students poses a major challenge for anatomy educators. In the present study, we describe the design and initial implementation of a near-peer Anatomy Teaching Assistant Program (AT-AP) and evaluate the students’ perceptions of its success. We demonstrate how, in addition to improving the anatomy education for undergraduate medical students, the teaching assistants (TAs; advanced medical and MD/Ph.D. students) were able to gain much needed experience for upcoming teaching responsibilities in their respective residencies. At the University Of Alabama School Of Medicine (UASOM), gross anatomy is not taught as one consecutive block but is interspersed within organ modules of the first 2 years of undergraduate medical education (UME). There has been a consistently low faculty-to-student ratio in the anatomy lab despite increasing student numbers. This shorthandedness has led to challenges in the gross anatomy laboratory setting. Addressing the issue by recruiting advanced medical students as teaching assistants (TAs) has been unsuccessful due to their rigid clinical scheduling. The goal of this study was to describe the design, successful implementation, and evaluation of a flexible co-enrolled elective Gross Anatomy Teaching Assistant Program within the context of an integrated system-based curriculum.

In a murine model, we have linked early life toxicant exposure to reduced uterine sensitivity to progesterone, a phenotype we had previously associated with inflammation in endometriosis patients. Subsequent studies revealed that developmental toxicant exposure not only reduces fertility in male and female mice but also negatively impacts pregnancy leading to spontaneous preterm birth (PTB), regardless of which parent was exposed. An epigenetic alteration of the progesterone receptor gene correlated with reduced fertility and adverse pregnancy outcomes and persisted in multiple generations of mice in the absence of an additional toxicant exposure. Gene–environment interactions in women may explain why some patients “at risk” for PTB deliver at term while others without known risks deliver early. Our model provides a unique system to unravel the interactive influences of inflammation and reduced progesterone responsiveness on PTB. Our model suggests that therapy needs to begin prior to conception (and involve both partners) rather than during pregnancy once the inflammatory cascade has been initiated.

Endometriosis is a painful disorder defined by extrauteral endometrial growths whose contribution to pain symptoms is poorly understood. Endometriosis is created in rats by autotransplanting on abdominal arteries pieces of either uterus (ENDO), which form cysts, or fat (shamENDO), which do not form cysts. ENDO, but not shamENDO induces vaginal hyperalgesia. We tested the hypothesis that the cysts are necessary to maintain vaginal hyperalgesia by assessing the effect of surgically removing them. Complete cyst removal eliminated ENDO-induced vaginal hyperalgesia up to four months post-operatively. Sham-cyst-removal in ENDO rats, in which cysts were not removed, or partial cyst-removal increased the ENDO-induced hyperalgesia. The decreases and increases both took three to six weeks to develop. Changes in ENDO-induced hyperalgesia did not occur in a control group of ENDO rats who had no surgery after ENDO. In a double-surgery control group, neither shamENDO surgery nor a subsequent sham surgery that mimicked “removal” of non-existent cysts influenced vaginal nociception. In a no-surgery control group, vaginal nociception remained stable for > six months. The increases in ENDO-induced hyperalgesia produced by the sham-cyst-removal surgery were smaller in proestrus than in other estrous stages. During the other stages (but not during proestrus), sympathetic innervation of the cysts increased. These results suggest that maintenance of ENDO-induced vaginal hyperalgesia requires continued presence of at least some ectopic endometrial tissue, and that surgical treatment that fails to remove ectopic endometrial tissue can exacerbate the hyperalgesia, possibly due in part to an increase in the cysts’ sympathetic innervation.

The pituitary gland's ability to respond to the hypothalamic hormone GnRH (gonadotropin-releasing hormone) depends directly on the gonadotrope-specific expression of the GnRH receptor (GnRHR), a G-protein coupled transmembrane protein coded by the GnRHR gene. In the present study, we have investigated the potential regulatory role of seven noncanonical E-box enhancer sequences within the 856bp proximal 5'-flanking region of the mGnRHR gene in regulating transcription. These sequences are known to mediate the action of clock gene proteins on the expression of a diverse array of genes both central and peripheral. In the present studies the expression of all of the cognate clock genes was identified in the alphaT3-1 gonadotrope cell line. Additionally, luteinizing hormone-immunoreactive cells in the adult rodent pituitary gland were also shown to co-express the PERIOD-1 protein. By means of chromatin immunoprecipitation of alphaT3-1 nuclear extracts we were able to capture promoter fragments of the GnRHR and Period-1 genes, indicating that E-boxes in these promoters bind the CLOCK protein. RNA interference experiments with alphaT3-1 cells in which Bmal1 expression was attenuated also confirmed the involvement of E-boxes in transcriptional regulation of the mGnRHR gene. Subsequent luciferase reporter assay experiments with GnRHR constructs possessing intact or mutated E-boxes confirmed the use of these sequences for the regulation of mGnRH-R/luc expression. Transient overexpression of the dominant negative E-box-binding factor CLOCK-Delta19, or the inhibitory clock protein mPER1, markedly reduced CLOCK/BMAL1-driven mGnRH-R/luc expression in a dose-dependent fashion. Our data implicate the clock genes as important factors controlling GnRHR expression in murine gonadotrope cells.

Aging effects have been reported in endocrine, metabolic and behavioral circadian rhythms. The effects of age on the circadian system have been investigated primarily in rats and hamsters and only seldom in mice. Our aim was to assess the effects of two common “anti-aging” treatments, namely caloric restriction (CR) and melatonin substitution, on the circadian system of mice. Animals were subjected to phase delays of the light–dark cycle and constant darkness (DD). The most pronounced change in the murine circadian system was the length of the endogenous period, τ, which increased with age regardless of treatment. CR had diverse effects e.g., enabling a more rapid phase shift response while concomitantly leading to a fragmented circadian phenotype with considerable activity during the rest (light) phase. Melatonin enforced the adaptation to the light/dark cycle, thus facilitating a rapid reentrainment to phase delayed lighting conditions. Interestingly, the melatonin-substituted animals displayed an increase in locomotor activity under constant darkness and in 50% of all cases a biphasic (split) activity pattern. These results contribute to the phenotypic evaluation of two very different approaches to intervene in the age-related degeneration of the mammalian circadian system. As both CR and melatonin have negative and positive effects on the behavioral expression of clock function (i.e., fragmentation of rhythms vs. faster reentrainment), their usefulness in managing age-related circadian disorders may be limited.

Health impairments, including reproductive issues, are associated with working nights or rotating shifts. For example, shift work has been associated with an increased risk of irregular menstrual cycles, endometriosis, infertility, miscarriage, low birth weight or pre-term delivery, and reduced incidence of breastfeeding. Based on what is known about circadian regulation of endocrine rhythms in rodents (and much less in humans), the circadian clock is an integral regulatory part of the reproductive system. When this 24-h program is disordered by environmental perturbation (such as shift work) or genetic alterations, the endocrine system can be impaired. The purpose of this review is to explore the hypothesis that misalignment of reproductive hormones with the environmental light-dark cycle and/or sleep-wake rhythms can disrupt menstrual cycles, pregnancy, and parturition. We highlight the role of the circadian clock in regulating human reproductive physiology and shift work-induced pathology within each step of the reproductive axis while exploring potential mechanisms from the animal model literature. In addition to documenting the reproductive hazards of shift work, we also point out important gaps in our knowledge as critical areas for future investigation. For example, future studies should examine whether forced desynchronization disrupts gonadotropin secretion rhythms and whether there are sleep/wake schedules that are better or worse for the adaptation of the reproductive system to shift work. These studies are necessary in order to define not only whether or not shift work-induced circadian misalignment impairs reproductive capacity, but also to identify strategies for the future that can minimize this desynchronization.

Ovariectomy (OVX) leads to hyperphagia and weight gain in rats, which can be prevented by estradiol (E2) replacement; however, the role of endogenous E2 on feeding and energy homeostasis in female mice has not been well characterized. The primary goal of this study was to assess the relative contribution of increased energy intake and decreased energy expenditure to OVX-induced weight gain in female rats and mice. OVX led to hyperphagia in rats, but did not produce daily, nor cumulative, hyperphagia in mice. OVX decreased mass-specific metabolic rate in mice, but not in rats. OVX decreased home cage locomotor activity in both species. Pair-feeding attenuated OVX-induced weight gain in rats and produced both short- and long-term changes in expression of key hypothalamic genes involved in food intake and energy homeostasis, i.e., the anorexigenic neuropeptide pro-opiomelanocortin (POMC) and the orexigenic neuropeptides: melanin-concentrating hormone (MCH) and agouti-related peptide (AgRP). No differences in hypothalamic gene expression were observed between OVX'd and sham mice. The results suggest that OVX-induced weight gain is mediated by hyperphagia and reduced locomotor activity in rats, but that in mice, it is primarily mediated by reduced locomotor activity and metabolic rate.

We reported earlier that gonadotropin-releasing hormone (GnRH) activates period1 ( mPer1) gene expression in immortalized gonadotropes through protein kinase C and p42/44 mitogen-activated protein kinase pathways. GnRH stimulation also leads to the upregulation of early growth response protein 1 (EGR-1), a critical transcription factor for GnRH-induced luteinizing hormone beta (LHβ) synthesis. The parallels between the GnRH–LHβ and the GnRH–mPer1 pathways led us to explore whether EGR-1 is involved in the regulation of mPer1 expression in gonadotropes. Of particular interest was the presence of an EGR-1 binding site in the proximal promoter of the mPer1 gene. Stimulation of LβT2 gonadotrope cells with a GnRH agonist caused the rapid induction of Egr-1 mRNA, which was rapidly followed by mPer1 expression. Chromatin immunoprecipitation revealed that the mPer1 promoter can bind EGR-1, while site-directed mutagenesis experiments confirmed the involvement of Egr-1 sequences in maintaining basal and allowing GnRH-stimulated mPer1 transcription. By means of RNA interference experiments, it could also be demonstrated that silencing of Egr-1 expression resulted in markedly lower mPer1 transcript levels. This silencing effect of the Egr-1 siRNA could be rescued by transfecting the cells with an EGR-1 overexpression vector. In summary, these results all point to a role for the EGR-1 protein in transactivating both the LHβ as well as the mPer1 gene in pituitary gonadotrope cells.

The initiation and maintenance of reproductive function in mammals is critically dependent on the pulsatile secretion of gonadotropin-releasing hormone (GnRH). This peptide drives the pulsatile release of FSH and LH from the pituitary pars distalis via signaling pathways that are activated by the type I GnRH receptor (GnRH-R). Recently, a microarray analysis study reported that a number of genes, including mPer1, are induced by GnRH in immortalized gonadotrope cells. In view of these data, we have begun to analyze in detail the signaling pathways mediating the action of GnRH on mPer1 expression in these cells. Using quantitative real-time polymprose cho read (PCR), we could confirm that exposure of immortalized gonadotropes (LbetaT2 cells) to the GnRH analog, buserelin, markedly induces mPer1 (but not mPer2) expression. Consistent with GnRH receptor signaling via the protein kinase (PK)-C pathway, exposure of the cells to phorbol 12,13-dibutyrate rapidly elevates both mPer1 and LHbeta subunit mRNA levels, while pharmacological inhibition of PKC prevents the mPer1 and LHbeta response to buserelin. As GnRH is known to regulate gonadotropin synthesis via activation of p42/44 mitogen-activated protein kinase (MAPK) signaling pathways, we then examined the involvement of this pathway in regulating mPer1 expression in gonadotropes. Our data reveal that GnRH-induced mPer1 expression is blocked following acute exposure to a MAPK kinase inhibitor. Although the involvement of this signaling mechanism in the regulation of mPer1 is known in neurons, e.g., in the suprachiasmatic nuclei, the induction of mPer1 in gonadotropes represents a novel mechanism of GnRH signaling, whose functional significance is still under investigation.

Circadian rhythms of behaviour and gene expression are coupled to endogenous neuronal oscillators located in the hypothalamic suprachiasmatic nuclei (SCN), which are synchronised by the environmental light cycle. Besides light, other factors such as the pineal hormone melatonin, temperature and feeding have entraining properties. During senescence, the circadian system becomes weaker and susceptible to desynchronisation. It is unknown to what extent age-related changes are the result of the deterioration of the hypothalamic master clock. Supplementing ageing mice with melatonin as well as maintaining them on a hypocaloric diet extends the life span and delays age-related diseases. By means of DNA microarrays and the quantitative polymerase chain reaction, we have conducted an exploratory study to compare the effect of long-term melatonin substitution (MEL) and caloric restriction (CR) on circadian gene expression in hypothalamic samples, which contained the SCN as well as other important nuclei involved in nutrient balance, reproduction, and so on. Over 4% of the hypothalamic transcripts showed an overt circadian rhythm in expression, and many of these contain E boxes in their promoter regions, suggesting a direct regulation by circadian clock genes. MEL and CR significantly influenced some of these rhythmically expressed transcripts, but often in opposite ways. Importantly, our studies emphasise that the apparent direction of treatment effects (i.e. up-regulation versus down-regulation) depends on the time of day at which the samples are compared.

Before generating cDNA in a molecular biology lab,the researcher is confronted with choosing the appro-priate priming method for the previously isolated RNA.The most common methods utilize the poly(A) tail ofthe mRNA either by priming with an oligo(dT) primeror by using random hexamers that statistically bind tothe mRNA pool. Another method uses gene-specificprimers, but this shall not be discussed here, as the re-sulting cDNA is limited to one transcript. To obtain agood representation of sequences at the 3