Local tissue interactions govern pLL patterning in medaka.

Vertebrate organs are arranged in a stereotypic, species-specific position along the animal body plan. Substantial morphological variation exists between related species, especially so in the vastly diversified teleost clade. It is still unclear how tissues, organs and systems can accommodate such diverse scaffolds. Here, we use the distinctive arrangement of neuromasts in the posterior lateral line (pLL) system of medaka fish to address the tissue-interactions defining a pattern. We show that patterning in this peripheral nervous system is established by autonomous organ precursors independent of neuronal wiring. In addition, we target the keratin 15 gene to generate stuck-in-the-midline (siml) mutants, which display epithelial lesions and a disrupted pLL patterning. By using siml/wt chimeras, we determine that the aberrant siml pLL pattern depends on the mutant epithelium, since a wild type epithelium can rescue the siml phenotype. Inducing epithelial lesions by 2-photon laser ablation during pLL morphogenesis phenocopies siml genetic mutants and reveals that epithelial integrity defines the final position of the embryonic pLL neuromasts. Our results using the medaka pLL disentangle intrinsic from extrinsic properties during the establishment of a sensory system. We speculate that intrinsic programs guarantee proper organ morphogenesis, while instructive interactions from surrounding tissues facilitates the accommodation of sensory organs to the diverse body plans found among teleosts.

Development and regeneration dynamics of the Medaka notochord.

The notochord is an embryonic tissue that acts as a hydrostatic skeleton until ossification begins in vertebrates. It is composed of outer sheath cells and inner vacuolated cells, which are generated from a common pool of disc-shaped precursors. Notochord extension during early embryogenesis is driven by the growth of vacuolated cells, reflecting in turn the expansion of their inner vacuole. Here we use desmogon, a novel desmosomal cadherin, to follow notochord development and regeneration in medaka (Oryzias latipes). We trace desmogon â€‹+ disc-shaped precursors at the single cell level to demonstrate that they operate as unipotent progenitors, giving rise to either sheath or vacuolated cells. We reveal that once specified, vacuolated cells grow asynchronously and drive notochord expansion bi-directionally. Additionally, we uncover distinct regenerative responses in the notochord, which depend on the nature of the injury sustained. By generating a desmogon CRISPR mutant we demonstrate that this cadherin is essential for proper vacuolated cell shape and therefore correct notochord and spine morphology. Our work expands the repertoire of model systems to study dynamic aspects of the notochord in vivo, and provides new insights in its development and regeneration properties.

Outcomes of Prehospital Chemical Sedation With Ketamine Versus Haloperidol and Benzodiazepine or Physical Restraint Only.

OBJECTIVE: The goal of this study is to describe complications and outcomes of prehospital ketamine use for agitation as compared to other methods of physical or chemical restraint such as haloperidol plus benzodiazepine or physical restraint only. METHODS: We conducted a single-center retrospective review of patient encounters in which restraint was administered in the prehospital setting. At the beginning of our study window, only physical restraint was available to paramedics managing agitated patients but subsequently, haloperidol and benzodiazepines were introduced, followed by ketamine 2 years later. By comparing patients before and after each transition, we divided subjects into 3 cohorts based on restraint type: physical restraint, haloperidol plus benzodiazepine, and ketamine. Demographic data were collected, and outcome measures included intubation rate, need for additional physical or chemical restraint, emergency department (ED) length of stay, need for hospital admission, and employee injury. RESULTS: Of 214 subjects included in the study, 95 patients were administered ketamine, 68 received haloperidol and benzodiazepine, and 51 were physically restrained. Eleven of the patients (11.6%) who received ketamine were intubated. Compared to patients who received haloperidol plus benzodiazepine, patients who received ketamine were more likely to be intubated (odds ratio [OR] = 8.77, 95% confidence interval [CI], 1.10-69.68) and were more likely to require additional chemical restraint when compared to haloperidol/benzodiazepine or physical restraint only (OR =2.94, 95% CI, 1.49-5.80, and OR =2.15, 95% CI, 1.07-4.31, respectively). There were no differences between the 2 chemical sedation groups in terms of ED length of stay or hospital admission rate. CONCLUSIONS: This study demonstrates a lower intubation rate in patients administered ketamine than prior literature in association with a lower weight-based dosing regimen. Ketamine use was correlated with a higher frequency of intubation and a greater need for additional chemical restraint when compared with other restraint modalities, though exogenous factors such as provider preference may have impacted this result. There was no difference in ED length of stay or admission rate between the ketamine and haloperidol plus benzodiazepine groups. Further prospective study is needed to determine whether there is a subset of patients for whom ketamine would be beneficial compared to other therapies.

Temporal and clonal characterization of neural stem cell niche recruitment in the medaka neuromast.

Stem cell populations are defined by their capacity to self-renew and to generate differentiated progeny. These unique characteristics largely depend on the stem cell micro-environment, the so-called stem cell niche. Niches were identified for most adult stem cells studied so far, but we know surprisingly little about how somatic stem cells and their niche come together during organ formation. Using the neuromasts of teleost fish, we have previously reported that neural stem cells recruit their niche from neighboring epithelial cells, which go through a morphological and molecular transformation. Here, we tackle quantitative, temporal, and clonal aspects of niche formation in neuromasts by using 4D imaging in transgenic lines, and lineage analysis in mosaic fish. We show that niche recruitment happens in a defined temporal window during the formation of neuromasts in medaka, and after that, the niche is enlarged mainly by the proliferation of niche cells. Niche recruitment is a non-clonal process that feeds from diverse epithelial cells that do not display a preferential position along the circumference of the forming neuromast. Additionally, we cover niche formation and expansion in zebrafish to show that distant species show common features during organogenesis in the lateral line system. Overall, our findings shed light on the process of niche formation, fundamental for the maintenance of stem cells not only in medaka but also in many other multicellular organisms.

A Dispatch Screening Tool to Identify Patients at High Risk for COVID-19 in the Prehospital Setting.

INTRODUCTION: Emergency medical services (EMS) dispatchers have made efforts to determine whether patients are high risk for coronavirus disease 2019 (COVID-19) so that appropriate personal protective equipment (PPE) can be donned. A screening tool is valuable as the healthcare community balances protection of medical personnel and conservation of PPE. There is little existing literature on the efficacy of prehospital COVID-19 screening tools. The objective of this study was to determine the positive and negative predictive value of an emergency infectious disease surveillance tool for detecting COVID-19 patients and the impact of positive screening on PPE usage. METHODS: This study was a retrospective chart review of prehospital care reports and hospital electronic health records. We abstracted records for all 911 calls to an urban EMS from March 1-July 31, 2020 that had a documented positive screen for COVID-19 and/or had a positive COVID-19 test. The dispatch screen solicited information regarding travel, sick contacts, and high-risk symptoms. We reviewed charts to determine dispatch-screening results, the outcome of patients' COVID-19 testing, and documentation of crew fidelity to PPE guidelines. RESULTS: The sample size was 263. The rate of positive COVID-19 tests for all-comers in the state of Massachusetts was 2.0%. The dispatch screen had a sensitivity of 74.9% (confidence interval [CI], 69.21-80.03) and a specificity of 67.7% (CI, 66.91-68.50). The positive predictive value was 4.5% (CI, 4.17-4.80), and the negative predictive value was 99.3% (CI, 99.09-99.40). The most common symptom that triggered a positive screen was shortness of breath (51.5% of calls). The most common high-risk population identified was skilled nursing facility patients (19.5%), but most positive tests did not belong to a high-risk population (58.1%). The EMS personnel were documented as wearing full PPE for the patient in 55.7% of encounters, not wearing PPE in 8.0% of encounters, and not documented in 27.9% of encounters. CONCLUSION: This dispatch-screening questionnaire has a high negative predictive value but moderate sensitivity and therefore should be used with some caution to guide EMS crews in their PPE usage. Clinical judgment is still essential and may supersede screening status.

Patient Outcomes Following Ketamine Administration for Acute Agitation with a Decreased Dosing Protocol in the Prehospital Setting.

BACKGROUND: Agitated behaviors are frequently encountered in the prehospital setting and require emergent treatment to prevent harm to patients and prehospital personnel. Chemical sedation with ketamine works faster than traditional pharmacologic agents, though it has a higher incidence of adverse events, including intubation. Outcomes following varying initial doses of prehospital intramuscular (IM) ketamine use have been incompletely described. OBJECTIVE: To determine whether using a lower dose IM ketamine protocol for agitation is associated with more favorable outcomes. METHODS: This study was a pre-/post-intervention retrospective chart review of prehospital care reports (PCRs). Adult patients who received chemical sedation in the form of IM ketamine for agitated behaviors were included. Patients were divided into two cohorts based on the standard IM ketamine dose of 4mg/kg and the lower IM dose of 3mg/kg with the option for an additional 1mg/kg if required. Primary outcomes included intubation and hospital admission. Secondary outcomes included emergency department (ED) length of stay, additional chemical or physical restraints, assaults on prehospital or ED employees, and documented adverse events. RESULTS: The standard dose cohort consisted of 211 patients. The lower dose cohort consisted of 81 patients, 17 of whom received supplemental ketamine administration. Demographics did not significantly differ between the cohorts (mean age 35.14 versus 35.65 years; P = .484; and 67.8% versus 65.4% male; P = .89). Lower dose subjects were administered a lower ketamine dose (mean 3.24mg/kg) compared to the standard dose cohort (mean 3.51mg/kg). There was no statistically significant difference between the cohorts in intubation rate (14.2% versus 18.5%; P = .455), ED length of stay (14.31 versus 14.88 hours; P = .118), need for additional restraint and sedation (P = .787), or admission rate (26.1% versus 25.9%; P = .677). In the lower dose cohort, 41.2% (7/17) of patients who received supplemental ketamine doses were intubated, a higher rate than the patients in this cohort who did not receive supplemental ketamine (8/64, 12.5%; P <.01). CONCLUSION: Access to effective, fast-acting chemical sedation is paramount for prehospital providers. No significant outcomes differences existed when a lower dose IM ketamine protocol was implemented for prehospital chemical sedation. Patients who received a second dose of ketamine had a significant increase in intubation rate. A lower dose protocol may be considered for an agitation protocol to limit the amount of medication administered to a population of high-risk patients.

Consumer credit card use: the roles of creditor disclosure and anticipated emotion.

In response to federal legislative reform aimed, in part, at reducing consumer bankruptcy filings, the authors conducted 2 experiments examining the role of affect in purchasing behavior. In Experiment 1, they examined consumer debtors, and in Experiment 2, they examined nondebtors. In both experiments, they investigated purchasing decisions made during a simulated online shopping trip, with some participants receiving standard disclosures of interest rates and money owed and with other participants receiving information under the new enhanced disclosure regulations. Results demonstrated support for the influence of anticipated affect in credit card use among both debtors and nondebtors and indicated that anticipated emotion may moderate the impact of the enhanced disclosure regulations.

Debtor education, financial literacy, and pending bankruptcy legislation.

This paper reports on an evaluation of a financial education-training program for residents of New York who had filed for bankruptcy. Over 400 individuals divided into three groups (trained debtors, untrained debtors, and non-debtors) completed identical questionnaires approximately three months apart. Trained debtors took the pretest before training and the post-test after training. Results revealed that trained debtors' financial knowledge increased after training compared with untrained and non-debtors. Trained debtors showed more negative attitudes towards unnecessary spending compared with the other two groups and reported less intention to buy than non-debtors reported. Self-reported behaviors showed significant changes in the desired direction for trained debtors' use of credit cards (i.e. number owned, purchases, and balance amount), paying bills, budgeting, and borrowing from predatory lenders. Implications for pending legislation are discussed.

The Effectiveness of Two Sonic and Two Ultrasonic Sealer Tips in Furcations.

This study compared the effectiveness of two sonic and two ultrasonic sealer tips on artificial calculus removal from the furcations of mandibular first and second molars. Twenty-four extracted mandibular molars were cleaned and randomly assigned to one of four treatment groups. Teeth were split buccal lingually, artificial calculus was placed in the furcation areas, and the teeth were photographed with a stereo camera. Teeth were reconnected with bonding material and mounted in a typodont with simulated gingiva and attached to a dental chair. Teeth were instrumented with either a Cavitron TFI10 tip, Cavitron EWPP tip, Titan-S Universal tip, or Titan-S Sickle tip by a licensed dental hygienist until each tooth was judged calculus free to the touch with a CH3 explorer. Time for each instrumentation period was recorded. Following instrumentation, the teeth were again split and photographed. Stereophotogrammetry was used to produce tracings of the teeth with initial calculus and remaining calculus. Pre-instrumentation and post-instrumentation amounts of calculus on the surface area were computed using the Bloquant system. A two factor analysis of variance was conducted followed with a Newman-Keuls Multiple Comparison Technique to test for within and between differences. Significant differences (P ≤ 0.01) were found between pre- and post-amounts of calculus for all tips. No significant differences (P ≤ 0.05) were found between the four instrument tips with respect to percentage of furcation surface with calculus remaining. No differences were found between tips with regard to the time required to clean the test surfaces.

Involvement of fumarate hydratase in nonsyndromic uterine leiomyomas: genetic linkage analysis and FISH studies.

Recently, germline mutations of the fumarate hydratase (FH) gene, in 1q42.1, have been found to be involved in syndromes associated with uterine leiomyomas (ULs). Compelling evidence also supports a genetic liability to develop nonsyndromic UL, although susceptibility genes have not been reported to date. Loss of heterozygosity (LOH) studies have found no or rare evidence of LOH of FH in nonsyndromic UL. However, the karyotypes of these tumors were not reported, and cytogenetic aberrations of 1q42-44 have been observed infrequently in UL. To determine whether FH mutations also may predispose women to developing nonsyndromic UL, we performed a genetic linkage study with DNA from 123 families containing at least one affected sister pair. In addition, to assess the frequency of FH loss specifically in UL with 1q rearrangements, we performed a fluorescence in situ hybridization (FISH) analysis of UL with 1q rearrangements. Analysis of the genotyping data revealed evidence suggestive of linkage to the FH region among study participants who were less than 40 years of age at diagnosis (Zlr 1.7 at D1S547, P = 0.04). FISH results showed that one copy of FH was absent in 9 of 11 ULs. These data indicate that loss of FH might be a significant event in the pathogenesis of a subset of nonsyndromic ULs.

HMGA2 expression in uterine leiomyomata and myometrium: quantitative analysis and tissue culture studies.

The high mobility group gene, HMGA2, is frequently expressed in uterine leiomyomata (UL) with chromosomal rearrangements of 12q15. In contrast, HMGA2 expression has not been detected in karyotypically normal UL or in myometrium, but has been detected in these tissues after culture. To characterize further the expression pattern of HMGA2, we assessed HMGA2 expression by RT-PCR followed by Southern blot hybridization, and by real-time PCR in three tissue panels: (1) primary myometrial cultures, (2) uncultured tissue from 15 karyotypically normal samples consisting of eleven 46,XX UL and four matched myometrial specimens, and (3) uncultured tissue from ten UL with 12q15 rearrangements and three matched myometrial specimens. HMGA2 expression was detected in all samples from the three panels. The level of HMGA2 expression in karyotypically normal UL was similar to the level of expression in myometrium; however, it was significantly less than the level measured in UL with 12q15 rearrangements. This expression analysis by use of detection methods of different sensitivities underscores the importance of studies of HMGA2 expression in uncultured tissues and of careful interpretation of results from experiments on cultured cells. Moreover, detection of HMGA2 expression in myometrium and in UL without 12q15 rearrangements, tissues previously thought not to express HMGA2, suggests that HMGA2 expression is required in normal adult myometrial physiology.