Engineered Biological Neural Networks on High Density CMOS Microelectrode Arrays.

In bottom-up neuroscience, questions on neural information processing are addressed by engineering small but reproducible biological neural networks of defined network topology in vitro. The network topology can be controlled by culturing neurons within polydimethylsiloxane (PDMS) microstructures that are combined with microelectrode arrays (MEAs) for electric access to the network. However, currently used glass MEAs are limited to 256 electrodes and pose a limitation to the spatial resolution as well as the design of more complex microstructures. The use of high density complementary metal-oxide-semiconductor (CMOS) MEAs greatly increases the spatial resolution, enabling sub-cellular readout and stimulation of neurons in defined neural networks. Unfortunately, the non-planar surface of CMOS MEAs complicates the attachment of PDMS microstructures. To overcome the problem of axons escaping the microstructures through the ridges of the CMOS MEA, we stamp-transferred a thin film of hexane-diluted PDMS onto the array such that the PDMS filled the ridges at the contact surface of the microstructures without clogging the axon guidance channels. This method resulted in 23 % of structurally fully connected but sealed networks on the CMOS MEA of which about 45 % showed spiking activity in all channels. Moreover, we provide an impedance-based method to visualize the exact location of the microstructures on the MEA and show that our method can confine axonal growth within the PDMS microstructures. Finally, the high spatial resolution of the CMOS MEA enabled us to show that action potentials follow the unidirectional topology of our circular multi-node microstructure.

Dimensions of Thermal Inequity: Neighborhood Social Demographics and Urban Heat in the Southwestern U.S.

Exposure to heat is a growing public health concern as climate change accelerates worldwide. Different socioeconomic and racial groups often face unequal exposure to heat as well as increased heat-related sickness, mortality, and energy costs. We provide new insight into thermal inequities by analyzing 20 Southwestern U.S. metropolitan regions at the census block group scale for three temperature scenarios (average summer heat, extreme summer heat, and average summer nighttime heat). We first compared average temperatures for top and bottom decile block groups according to demographic variables. Then we used spatial regression models to investigate the extent to which exposure to heat (measured by land surface temperature) varies according to income and race. Large thermal inequities exist within all the regions studied. On average, the poorest 10% of neighborhoods in an urban region were 2.2 °C (4 °F) hotter than the wealthiest 10% on both extreme heat days and average summer days. The difference was as high as 3.3-3.7 °C (6-7 °F) in California metro areas such as Palm Springs and the Inland Empire. A similar pattern held for Latinx neighborhoods. Temperature disparities at night were much smaller (usually ~1 °F). Disparities for Black neighborhoods were also lower, perhaps because Black populations are small in most of these cities. California urban regions show stronger thermal disparities than those in other Southwestern states, perhaps because inexpensive water has led to more extensive vegetation in affluent neighborhoods. Our findings provide new details about urban thermal inequities and reinforce the need for programs to reduce the disproportionate heat experienced by disadvantaged communities.

A Blended Prehospital Ultrasound Curriculum for Critical Care Paramedics.

OBJECTIVE: Point-of-care ultrasound is a nascent and growing area of prehospital care. Most previously described ultrasound curricula for paramedics examine a single type of ultrasound scan. Here, we describe the implementation and evaluation of a prehospital ultrasound curriculum using a blended model of traditional didactics and hands-on experience with online prereading. METHODS: We recruited a prospective convenience sample of critical care paramedics without prior ultrasound experience to take part in a 2-day ultrasound course. All participants completed prereading modules built from online resources followed by a didactic review of the material and hands-on practice. Ultrasound examinations included extended focused abdominal sonography in trauma, cardiac ultrasound, thoracic ultrasound, and vascular ultrasound. A written examination evaluated ultrasound theory and image interpretation, and a practical examination evaluated image acquisition. RESULTS: Seventeen critical care paramedics completed the course with a mean grade on the written examination of 76%, with 76% of paramedics achieving the predetermined passing mark of 70% or greater. All paramedics passed the practical examination. CONCLUSION: The implementation of a prehospital critical care ultrasound program is feasible in our provincial emergency medical services system. Further assessment is necessary to determine future knowledge and skill retention as well as clinical application and utility in real-world settings.

A controlled resuscitation strategy is feasible and safe in hypotensive trauma patients: results of a prospective randomized pilot trial.

BACKGROUND: Optimal resuscitation of hypotensive trauma patients has not been defined. This trial was performed to assess the feasibility and safety of controlled resuscitation (CR) versus standard resuscitation (SR) in hypotensive trauma patients. METHODS: Patients were enrolled and randomized in the out-of-hospital setting. Nineteen emergency medical services (EMS) systems in the Resuscitation Outcome Consortium participated. Eligible patients had an out-of-hospital systolic blood pressure (SBP) of 90 mm Hg or lower. CR patients received 250 mL of fluid if they had no radial pulse or an SBP lower than 70 mm Hg and additional 250-mL boluses to maintain a radial pulse or an SBP of 70 mm Hg or greater. The SR group patients received 2 L initially and additional fluid as needed to maintain an SBP of 110 mm Hg or greater. The crystalloid protocol was maintained until hemorrhage control or 2 hours after hospital arrival. RESULTS: A total of 192 patients were randomized (97 CR and 95 SR). The CR and SR groups were similar at baseline. The mean (SD) crystalloid volume administered during the study period was 1.0 L (1.5) in the CR group and 2.0 L (1.4) in the SR group, a difference of 1.0 L (95% confidence interval [CI], 0.6-1.4). Intensive care unit-free days, ventilator-free days, renal injury, and renal failure did not differ between the groups. At 24 hours after admission, there were 5 deaths (5%) in the CR group and 14 (15%) in the SR group (adjusted odds ratio, 0.39; 95% CI, 0.12-1.26). Among patients with blunt trauma, 24-hour mortality was 3% (CR) and 18% (SR) with an adjusted odds ratio of 0.17 (0.03-0.92). There was no difference among patients with penetrating trauma (9% vs. 9%; adjusted odds ratio, 1.93; 95% CI, 0.19-19.17). CONCLUSION: CR is achievable in out-of-hospital and hospital settings and may offer an early survival advantage in blunt trauma. A large-scale, Phase III trial to examine its effects on survival and other clinical outcomes is warranted. LEVEL OF EVIDENCE: Therapeutic study, level I.

Does direct transport to provincial burn centres improve outcomes? A spatial epidemiology of severe burn injury in British Columbia, 2001-2006.

BACKGROUND: In Canada and the United States, research has shown that injured patients initially treated at smaller emergency departments before transfer to larger regional facilities are more likely to require longer stays in hospital or suffer greater mortality. It remains unknown whether transport status is an independent predictor of adverse health events among persons requiring care from provincial burn centres. METHODS: We obtained case records from the British Columbia Trauma Registry for adult patients (age ≥ 18 yr) referred or transported directly to the Vancouver General Hospital and Royal Jubilee Hospital burn centres between Jan. 1, 2001, and Mar. 31, 2006. Prehospital and in-transit deaths and deaths in other facilities were identified using the provincial Coroner Service database. Place of injury was identified through data linkage with census records. We performed bivariate analysis for continuous and discrete variables. Relative risk (RR) of prehospital and in-hospital mortality and hospital stay by transport status were analyzed using a Poisson regression model. RESULTS: After controlling for patient and injury characteristics, indirect referral did not influence RR of in-facility death (RR 1.32, 95% confidence interval [CI] 0.54- 3.22) or hospital stay (RR 0.96, 95% CI 0.65-1.42). Rural populations experienced an increased risk of total mortality (RR 1.22, 95% CI 1.00-1.48). CONCLUSION: Transfer status is not a significant indicator of RR of death or hospital stay among patients who received care at primary care facilities before transport to regional burn centres. However, significant differences in prehospital mortality show that improvements in rural mortality can still be made.

Pneumomediastinum after inhalation of helium gas from party balloons.

A previously healthy 16-year-old boy presented to the Emergency Department with a 2-day history of hoarseness, sore throat, and chest tightness. The physical examination was significant for diffuse neck and chest subcutaneous emphysema. A computed tomography (CT) scan of the neck and chest revealed pneumomediastinum after a plain chest X-ray study failed to uncover this finding. The patient reported that 5 days before presentation he forcefully inhaled helium gas directly from multiple party balloons in an attempt to alter his voice. The patient fully recovered over the next 2 days. Spontaneous pneumomediastinum developed in this patient with no underlying lung disease, presumably from air leakage secondary to the excessive elevation of intra-thoracic pressure due to repetitive inhalation of helium gas. Spontaneous pneumomediastinum remains largely underdiagnosed clinically, especially in young, healthy patients.

Complication or substandard care? Risks of inadequate implant training.

The use of dental implants has increased substantially over the past decade, as have the number of implant-related complications. One of the contributing factors is inadequate training in the prevention, recognition, and treatment of complications. Comprehensive training on implant surgical procedures that includes patient selection, risk management, and complications allows dentists to incorporate implant placement into their practices with less risk to patients and less risk of serious legal consequences.

Implant complications in the esthetic zone.

PURPOSE: To review treatment planning concepts and surgical techniques that have led to complications during implant reconstruction in the anterior maxilla. PATIENTS AND METHODS: The conclusions in this paper are based on a review of the current literature, along with personal experience in private practice over the past 20 years. RESULTS: Treatment planning recommendations based on clinical studies have led to a significant decrease in functional and esthetic complications in the anterior maxilla. These involve surgical placement and spacing of implants, along with timing and grafting considerations. CONCLUSIONS: Research and clinical results indicate that cautious timing of site preparation and implant placement, along with important concepts of implant spacing, can significantly reduce complications within the esthetic zone.

Population-based analysis of severe injuries from nonmotorized wheeled vehicles.

BACKGROUND: Bicycling, skateboarding, and inline skating are popular recreational activities, with the potential of causing severe injury. METHODS: A retrospective, population-based, trauma registry analysis of severe injuries and deaths from nonmotorized wheeled vehicles (NMWV) over a 10-year period was performed. RESULTS: During the study period, 1475 cyclists, 141 skateboarders, and 112 inline skaters sustained injury meeting registry criteria (length of stay > or = 3 days or death). The majority were male. Lone crashes were the most common mechanism of injury, although collisions with motor vehicles accounted for 63.6% (n = 44) of observed deaths. Thoracic trauma and head injuries were more common in nonsurvivors. CONCLUSION: NMWV injuries pose a public health concern. We recommend enforcement of mandatory helmet laws and expansion of the existing law to include skateboarders and inline skaters. Education initiatives should also be expanded to include the adult population. NMWV should be separated from motorized vehicles as much as possible.

Vasomotor rhinitis.

Vasomotor rhinitis affects millions of Americans and results in significant symptomatology. Characterized by a combination of symptoms that includes nasal obstruction and rhinorrhea, vasomotor rhinitis is a diagnosis of exclusion reached after taking a careful history, performing a physical examination, and, in select cases, testing the patient with known allergens. According to a 2002 evidence report published by the Agency for Healthcare Research and Quality (AHRQ), there is insufficient evidence to reliably differentiate between allergic and nonallergic rhinitis based on signs and symptoms alone. The minimum level of diagnostic testing needed to differentiate between the two types of rhinitis also has not been established. An algorithm is presented that is based on a targeted history and physical examination and a stepwise approach to management that reflects the AHRQ evidence report and U.S. Food and Drug Administration approvals. Specific approaches to the management of rhinitis in children, athletes, pregnant women, and older adults are discussed.

Hyperthyroidism: diagnosis and treatment.

The proper treatment of hyperthyroidism depends on recognition of the signs and symptoms of the disease and determination of the etiology. The most common cause of hyperthyroidism is Graves' disease. Other common causes include thyroiditis, toxic multinodular goiter, toxic adenomas, and side effects of certain medications. The diagnostic workup begins with a thyroid-stimulating hormone level test. When test results are uncertain, measuring radionuclide uptake helps distinguish among possible causes. When thyroiditis is the cause, symptomatic treatment usually is sufficient because the associated hyperthyroidism is transient. Graves' disease, toxic multinodular goiter, and toxic adenoma can be treated with radioactive iodine, antithyroid drugs, or surgery, but in the United States, radioactive iodine is the treatment of choice in patients without contraindications. Thyroidectomy is an option when other treatments fail or are contraindicated, or when a goiter is causing compressive symptoms. Some new therapies are under investigation. Special treatment consideration must be given to patients who are pregnant or breastfeeding, as well as those with Graves' ophthalmopathy or amiodarone-induced hyperthyroidism. Patients' desires must be considered when deciding on appropriate therapy, and dose monitoring is essential.

Use of the Frialit-2 Implant System in private practice: a clinical report.

This retrospective study presents the results of the use of the Frialit-2 System in a private practice setting. A total of 802 implants, both threaded and press-fit, were placed between February 2, 1996, and March 6, 2002. The overall success rate was 97%, and the cumulative survival rate using life table analysis was 96.1%. The statistical breakdown and an analysis of the results of the treatment of this patient population are presented.

Introducing practice-based learning and improvement ACGME core competencies into a family medicine residency curriculum.

BACKGROUND: The Accreditation Council for Graduate Medical Education (ACGME) recommends integrating improvement activities into residency training. A curricular change was designed at the Department of Family and Community Medicine, University of Louisville, to address selected ACGME competencies by incorporating practice-based improvement activities into the routine clinical work of family medicine residents. METHODS: Teams of residents, faculty, and office staff completed clinical improvement projects at three ambulatory care training sites. Residents were given academic credit for participation in team meetings. After 6 months, residents presented results to faculty, medical students, other residents, and staff from all three training sites. Residents, staff, and faculty were recognized for their participation. PROGRAM EVALUATION: Resident teams demonstrated ACGME competencies in practice-based improvement: Chart audits indicated improvement in clinical projects; quality improvement tools demonstrated analysis of root causes and understanding of the process; plan-do-study-act cycle worksheets demonstrated the change process. CONCLUSIONS: Improvement activities that affect patient care and demonstrate selected ACGME competencies can be successfully incorporated into the daily work of family medicine residents.

Communication between family physicians and registered dietitians in the outpatient setting.

OBJECTIVE: To elicit how registered dietitians and family physicians communicate in the outpatient setting. DESIGN: A descriptive pilot study using two mailed surveys was conducted to elicit aspects of outpatient communication between registered dietitians and family physicians. A sample of nutrition correspondence from registered dietitians to family physicians was also requested. SUBJECTS: Surveys were distributed to 504 licensed dietitians and 626 family physicians. STATISTICAL ANALYSES: Descriptive statistics were used to analyze survey results. RESULTS: Responses were received from 389 registered dietitians (77% return rate) and 235 family physicians (37.5% return rate). We received 104 sample notes of correspondence with physicians from dietitians. Among dietitians, 80% reported that they always assess a patient's lifestyle and educational level before choosing an educational approach, and 69% send the nutrition treatment plan to the referring family physician. Among family physicians, 49% often or always find the communications they receive from registered dietitians to be helpful. However, 41% of family physicians reported that they rarely receive detailed nutrition assessments or recommendations about the referred patient from the dietitian, and 54% of all family physicians surveyed often think that this lack of feedback compromises patient care. APPLICATIONS/CONCLUSION: Dietitians can improve communications with family physicians by standardizing the format and focus of nutrition correspondence and assuring that the referring family physician receives the patient's nutrition care plan. These simple changes would close a very important communication loop, forge stronger partnerships between dietitians and family physicians, and potentially improve patient outcomes.