Nitrogen-Vacancy Magnetic Relaxometry of Nanoclustered Cytochrome C Proteins.

Nitrogen-vacancy (NV) magnetometry offers an alternative tool to detect paramagnetic centers in cells with a favorable combination of magnetic sensitivity and spatial resolution. Here, we employ NV magnetic relaxometry to detect cytochrome C (Cyt-C) nanoclusters. Cyt-C is a water-soluble protein that plays a vital role in the electron transport chain of mitochondria. Under ambient conditions, the heme group in Cyt-C remains in the Fe3+ state, which is paramagnetic. We vary the concentration of Cyt-C from 6 to 54 µM and observe a reduction of the NV spin-lattice relaxation time (T1) from 1.2 ms to 150 µs, which is attributed to the spin noise originating from the Fe3+ spins. NV T1 imaging of Cyt-C drop-casted on a nanostructured diamond chip allows us to detect the relaxation rates from the adsorbed Fe3+ within Cyt-C.

Coordination Chemistry of Uranyl Ions with Surface-Immobilized Peptides: An XPS Study.

The coordination chemistry of uranyl ions with surface immobilized peptides was studied using X-ray photoemission spectroscopy (XPS). All the peptides in the study were modified using a six-carbon alkanethiol as a linker on a gold substrate with methylene blue as the redox label. The X-ray photoemission spectra reveal that each modified peptide interacts differently with the uranyl ion. For all the modified peptides, the XPS spectra were taken in both the absence and presence of the uranium, and their comparison reveals that the interaction depends on the chemical group present in the peptides. The XPS results show that, among all the modified peptides in the current study, the (arginine)9 (R9) modified peptide showed the largest response to uranium. In the order of response to uranium, the second largest response was shown by the modified (arginine)6 (R6) peptide followed by the modified (lysine)6 (K6) peptide. Other modified peptides, (alanine)6 (A6), (glutamic acid)6 (E6) and (serine)6 (S6), did not show any response to uranium.

Single injection, ultrasound-guided planar nerve blocks: An essential skill for any clinician caring for patients with rib fractures.

In patients with acute rib fractures, regional anesthesia has the potential to reduce suffering, decrease opiate use, lower rates of in-hospital delirium, and improve pulmonary function. While many regional anesthesia techniques are complex and time consuming, two single injection nerve blocks, the serratus anterior plane block and erector spinae plane block, are particularly fast, safe, and simple methods to anesthetize the chest wall. Herein we describe two cases in which the serratus anterior plane block and erector spinae plane block were each used with great success in achieving improved pain control in trauma patients with multiple rib fractures. We believe that any provider who routinely cares for patients with rib fractures (emergency physicians and trauma surgeons alike) can and should learn to use these straightforward nerve blocks.

Implementation of the Cardiac Arrest Sonographic Assessment (CASA) protocol for patients with cardiac arrest is associated with shorter CPR pulse checks.

OBJECTIVE: We aim to evaluate whether implementation of the "Cardiac Arrest Sonographic Assessment" (CASA) protocol reduces the duration of interruptions in CPR during resuscitation of cardiac arrest (CA) compared to the pre-intervention period. METHODS: This was a quasi-experimental pre and post intervention study completed over 19 months in an urban Emergency Department. CA resuscitations were filmed and analyzed with respect to pulse check duration and use of point-of-care ultrasound (POCUS). After one year, an intervention was implemented: ED residents and faculty were taught the CASA protocol and instructed on how to implement it within CA resuscitation. The primary outcome was the difference in CPR pulse check duration between the pre and post intervention period. Videos from pre and post intervention CA resuscitations were coded by two reviewers. RESULTS: Data was collected prospectively for 267 sequential cardiac arrests. 38 pre-intervention and 45 post-intervention resuscitations were videoed and included in analysis. Both groups had a median of 3 pulse checks and 2 POCUS exams performed per code. CPR pulse checks involving POCUS exams were 4.0 s (95%CI 1.7-6.3) shorter in the post-intervention group than in the pre-intervention group. CPR pause durations were 3.1 s (95%CI 0.7-5.6) shorter when the ultrasound probe was placed on the chest before stopping CPR compared to placement after stopping CPR, and 3.1 s (95%CI 0.6-5.6) shorter when an ED ultrasound fellowship trained faculty was present compared to non-ultrasound fellowship faculty. The proportion of pulse checks with ultrasound use increased from 64% before the intervention to 80% after the intervention. CONCLUSION: In this pre and post-intervention study, the implementation of a structured algorithm for ultrasound use during cardiac arrest significantly reduced the duration of CPR interruptions when ultrasound was performed.

Patient demographic and health factors associated with frequent use of emergency medical services in a midsized city.

OBJECTIVES: To optimize health care utilization, health outcomes, and costs, research is needed to improve an understanding of frequent users of emergency health services. Frequent use of emergency services is associated with high costs of health care and may be indicative of challenges accessing, or poor outcomes of, health care. Patient demographics and health factors related to frequent use of the emergency medical services (EMS) system of a midsized city were identified. Study findings will aid in the development of targeted interventions to improve population health. METHODS: The authors reviewed 9-1-1 call dispatch data and Baltimore City Fire Department (BCFD) EMS records from 2008 through 2010. Frequent use was defined as six or more EMS incidents in the 23-month period. Analyses used census data to compare demographics of EMS users to their population distribution and examined differences in demographics and health problems of frequent EMS users compared to nonfrequent users. RESULTS: Frequent EMS users (n = 1,969) had a range of six to 199 EMS incidents (mean = 11.2) during the observation period, and although they accounted for only 1.5% of EMS users, they were involved in 12.0% of incidents. Frequent users, compared to nonfrequent users and to the population, were more likely to be male, African American, and 45 years of age or older. Of frequent users, the modal age group was 45 to 54 years, accounting for 29.7% of frequent users, which represented twice this age group's population distribution. Furthermore, this age group had the greatest overrepresentation of males (63.0% of frequent users) and was the peak age group for incidents related to substance abuse (28.0% of frequent users' incidents in this age group). Frequent users, compared to nonfrequent users, had lower levels of incidents related to trauma (5.1% vs. 16.7%) and higher levels of medical incidents (94.8% vs. 82.9%). As proportions of EMS incidents among frequent versus nonfrequent users, respiratory, mental health, and seizure-related incidents were highest in the youngest age groups; substance abuse-related incidents were highest in those middle-aged (35 to 44 and 45 to 54 years). Of health problems, behavioral health (mental health or substance use) contributed most to frequent EMS use (23.4% of frequent users' incidents). Across all incidents, 65.8% of frequent users had indications of behavioral health problems, representing 6.6-fold higher odds than nonfrequent users (22.5%). Frequent compared to nonfrequent users also had higher levels of select chronic conditions (diabetes, 39.9% vs. 14.6%; asthma, 40.9% vs. 13.4%; and HIV, 9.1% vs. 2.4%), with unadjusted odds almost four to seven times higher. CONCLUSIONS: The study findings revealed the major role of chronic somatic and behavioral health problems in frequent EMS use and that rates of frequent use were highest among those middle-aged, African American, and male. These results suggest the need for coordination of EMS with community-based, integrated medical and behavioral health services to improve access and use of preventive services, with implications for health outcomes and costs. This study demonstrates the value of EMS patient data in identifying at-risk populations and informing novel, targeted approaches to public health interventions.