Laser-Microfabricated Polymer Multielectrodes for Intraspinal Microstimulation.

OBJECTIVE: The overall goal of this study was to design, fabricate, and characterize a new polymer-based multielectrode for the spinal cord for the application of intraspinal microstimulation (ISMS). METHODS: Three-channel multielectrodes were fabricated from modified poly(dimethylsiloxane) (PDMS) and platinum-iridium (Pt-Ir) foil using nanosecond laser microfabrication techniques. These devices were compared against traditional 50 µm diameter Pt-Ir microwire electrodes mechanically and electrochemically in bench environments, and were assessed electrochemically and functionally in vivo in a domestic pig model. RESULTS: Polymer-based multielectrodes were significantly more flexible than microwire electrodes (p < 0.05) and had greater charge storage capacities in phosphate buffered saline (p < 0.05). In a domestic pig model, multielectrodes had significantly greater charge injection limits than microwire electrodes (p < 0.05). When stimulating within the quadriceps motor pool in the spinal cord, multielectrodes generated strong knee extensor joint torques of up to 4.4 ± 0.3 Nm and were able to extend the knee by up to 26 ± 1°. However, histological analyses showed that polymer-based multielectrodes, implanted with half-needle insertion aids, produced greater acute tissue damage compared to microwire electrodes (p < 0.05). Alternative insertion methods for these flexible electrodes should be explored to reduce acute tissue damage. CONCLUSION: The PDMS-based three-channel multielectrodes demonstrated improved flexibility and charge injection capabilities over traditional microwire electrodes, and were able to produce functional responses in vivo. SIGNIFICANCE: Polymer-based multielectrodes demonstrate improved functionality over microwire electrodes while remaining more flexible than silicon multielectrode designs. These features may in the future permit polymer-based multielectrodes to implement ISMS with greater efficacy and biocompatibility compared to traditional technologies.

Nutrition interventions for youth with dyslipidemia: a National Lipid Association clinical perspective.

A heart-healthy lifestyle, beginning at an early age and sustained throughout life, may reduce risk for cardiovascular disease in youth. Among youth with moderate to severe dyslipidemia and/or those with familial hypercholesterolemia, lipid-lowering medications are often needed for primary prevention of cardiovascular disease. However, lifestyle interventions are a foundation for youth with dyslipidemia, as well as those without dyslipidemia. There are limited data supporting the use of dietary supplements in youth with dyslipidemia at this time. A family-centered approach and the support of a multi-disciplinary healthcare team, which includes a registered dietitian nutritionist to provide nutrition counseling, provides the best opportunity for primary prevention and improved outcomes. While there are numerous guidelines that address the general nutritional needs of youth, few address the unique needs of those with dyslipidemia. The goal of this National Lipid Association Clinical Perspective is to provide guidance for healthcare professionals caring for youth with disorders of lipid and lipoprotein metabolism, including nutritional guidance that complements the use of lipid lowering medications.

Medical student research opportunities: a survey of osteopathic medical schools in the United States.

CONTEXT: It is important for colleges of osteopathic medicine (COMs) to provide opportunities for osteopathic medical students (OMSs) to conduct research under the guidance of professional researchers. However, COMs historically lag behind allopathic medical schools in research offerings for medical students. The literature would benefit from a synopsis of research opportunities for OMSs at COMs. OBJECTIVES: This study aims to assess the availability of research opportunities currently offered to OMSs and to identify structured research programs (SRPs) to provide data that may help COMs expand such opportunities. METHODS: Two online surveys were developed. The General Survey asked about general research opportunities, research requirements, and SRPs, which we define as optional, intramural, and mentored research programs. The follow-up SRP Survey sought to understand the history, funding, and organizational structure of SRPs. Between February and June 2021, the General and SRP Surveys were sent to all COMs in the United States. Response data were analyzed descriptively. RESULTS: Responses were received from 32 (84.2%) of 38 COMs. Nearly all COMs offered research symposia, offered third- or fourth-year research elective rotations, and provided some form of funding for OMSs to participate in research. Fourteen (43.8%) COMs had mandatory research requirements. Twenty COMs (62.5%) offered 31 SRPs, and surveys were completed for 25 (80.6%) SRPs. SRPs were founded a median (range) of 7 (1-43) years prior and accommodated 20 (4-50) OMSs annually. Among the responding SRPs, 12.0% had external funding, 96.0% required applications, 50.0% interviewed applicants prior to acceptance into the program, 72.0% required OMSs to identify their own mentors, 68.0% offered stipends to OMSs, 28.0% offered course credits, 96.0% had clinical research opportunities, and 68.0% offered research-oriented didactics. In 84.0% of SRPs, OMSs worked predominantly in the summer after OMS-I; for these SRPs, students had 4-10 weeks of dedicated time for participation in research. CONCLUSIONS: Findings from our surveys provide a synopsis of the research opportunities currently provided by COMs in the United States. Our data demonstrated wide variability of research opportunities among COMs.

Patterns of Prostate Cancer Recurrence After Brachytherapy Determined by Prostate-Specific Membrane Antigen-Positron Emission Tomography and Computed Tomography Imaging.

PURPOSE: The aim of this study was to characterize the patterns of prostate cancer recurrence after brachytherapy (BT) using 2-(3-[1-carboxy-5-([6-18F-fluoropyridine-3-carbonyl]-amino)-pentyl]-ureido)-pentanedioic acid ([18F]DCFPyL) prostate-specific membrane antigen (PSMA) positron emission tomography (PET) and computed tomography (CT) imaging. METHODS AND MATERIALS: Patients were selected from an ongoing prospective institutional trial investigating the use of [18F]DCFPyL PSMA PET and CT in recurrent prostate cancer (NCT02899312). This report included patients who underwent BT (either monotherapy or boost) and experienced a biochemical failure (BF) defined by the Phoenix definition (prostate-specific antigen [PSA] > 2 ng/mL above nadir). RESULTS: Between March 2017 and April 2020, 670 patients underwent [18F]DCFPyL PSMA PET and CT imaging. Of these 670 patients, 93 were treated with BT; 73 underwent monotherapy, and 20 underwent BT boost (19 low-dose rate and 1 high-dose rate). To report on patterns of recurrence outcomes, 86 patients (median prescan PSA 6.0) with a positive [18F]DCFPyL PSMA PET and CT scan and true BF were included. The most common location of relapse was local; 62.8% had a component of local failure (defined as prostate and/or seminal vesicles), and 46.5% had isolated local failure only, with no other sites of involvement. Regional failure occurred in 40.7% of patients, and 36.0% had metastatic failure. Isolated local recurrence was seen in 54.3% of monotherapy patients versus only in 12.5% of boost patients. Metastatic failure was seen in 28.6% of monotherapy patients versus 68.8% of the boost patients. Local recurrences (69.0%) were found within the same prostate biopsy sextant involved with the tumor at diagnosis, and 76.0% of patients with seminal vesicle recurrences had prostate-base involvement at diagnosis. CONCLUSIONS: Contrary to previous evidence, our study suggests that in prostate BT patients with biochemical recurrence, the most common site of failure is local for the patients treated with monotherapy and metastatic for patients treated with a combination of external beam radiation and BT boost.

Case Studies in Pediatric Lipid Disorders and Their Management.

CONTEXT: Identification of modifiable risk factors, including genetic and acquired disorders of lipid and lipoprotein metabolism, is increasingly recognized as an opportunity to prevent premature cardiovascular disease (CVD) in at-risk youth. Pediatric endocrinologists are at the forefront of this emerging public health concern and can be instrumental in beginning early interventions to prevent premature CVD-related events during adulthood. AIM: In this article, we use informative case presentations to provide practical approaches to the management of pediatric dyslipidemia. CASES: We present 3 scenarios that are commonly encountered in clinical practice: isolated elevation of low-density lipoprotein cholesterol (LDL-C), combined dyslipidemia, and severe hypertriglyceridemia. Treatment with statin is indicated when the LDL-C is ≥190 mg/dL (4.9 mmol/L) in children ≥10 years of age. For LDL-C levels between 130 and 189 mg/dL (3.4-4.89 mmol/L) despite dietary and lifestyle changes, the presence of additional risk factors and comorbid conditions would favor statin therapy. In the case of combined dyslipidemia, the primary treatment target is LDL-C ≤130 mg/dL (3.4 mmol/L) and the secondary target non-high-density lipoprotein cholesterol <145 mg/dL (3.7 mmol/L). If the triglyceride is ≥400 mg/dL (4.5 mmol/L), prescription omega-3 fatty acids and fibrates are considered. In the case of triglyceride >1000 mg/dL (11.3 mmol/L), dietary fat restriction remains the cornerstone of therapy, even though the landscape of medications is changing. CONCLUSION: Gene variants, acquired conditions, or both are responsible for dyslipidemia during childhood. Extreme elevations of triglycerides can lead to pancreatitis. Early identification and management of dyslipidemia and cardiovascular risk factors is extremely important.

Pediatric dyslipidemia: recommendations for clinical management.

During the last 50 years, it has become evident that atherosclerosis originates in childhood. Although cardiovascular disease (CVD) events are rare in children, autopsy data and imaging studies have documented subclinical disease in association with measurable risk factors during childhood. When present at a young age, risk factors track into adulthood and have been associated with a moderate to high risk of future CVD. As such, the ability to identify this vulnerable population creates the opportunity to prevent the development of risk factors and future CVD events with effective management of genetic and acquired risk factors. In 2011, the National Heart, Lung, and Blood Institute Expert Panel published comprehensive guidelines summarizing the current evidence and providing developmentally appropriate recommendations for screening, treatment, and follow-up of children and adults younger than 21 years at risk for premature CVDs such as myocardial infarction and stroke. In addition to screening individuals with a family history of hypercholesterolemia and/or premature CVD, the Expert Panel recommended universal screening of all children between 9 and 11 years of age and then again between 17 and 21 years of age. Although the recommendation for universal screening, regardless of general health or the presence/absence of risk factors of CVD, is not without controversy, this review serves to create awareness among healthcare providers, elected officials, and the lay public about the burden of CVD, the opportunity for prevention, and the benefits of early and effective therapeutic intervention with lifestyle changes and lipid-lowering medications.

The impact of high-dose vitamin C on blood glucose testing in ¹8F-FDG PET imaging.

Complementary and alternative therapies in addition to standard oncology protocols are commonly sought by cancer patients; however, few patients disclose their complementary treatments to their cancer care team. A lack of communication may result in unforeseen side effects and the potential for some alternative therapies to interfere with or inhibit conventional treatment. High-dose vitamin C therapy, in particular, may lead to an inability to measure a patient's blood glucose level before (18)F-FDG injection for PET/CT scanning. We report a case of a 52-y-old woman referred for (18)F-FDG PET/CT to evaluate the extent of recurrent colorectal cancer. The PET/CT scan immediately followed a single intravenous dose of 25 g of ascorbic acid from her naturopath. A glucometer that applies the glucose oxidase method for measuring fasting blood glucose was used, for which high doses of vitamin C are listed as a contraindication. The high concentration of ascorbic acid in the patient's blood sample interfered with the chemical reaction on the glucose strip, and therefore no blood glucose measurement could be attained. With more patients receiving alternative and complementary cancer therapies, it is important to know what the implications of orthomolecular therapy might be on routine blood glucose testing for (18)F-FDG PET scans. (18)F-FDG is in direct competition with glucose; therefore, elevated blood glucose levels will cause a decrease in (18)F-FDG absorption and may lead to a false-negative scan.

Familial chylomicronemia syndrome and response to medium-chain triglyceride therapy in an infant with novel mutations in GPIHBP1.

BACKGROUND: Severe hypertriglyceridemia predisposes to attacks of acute pancreatitis, a serious condition complicated by multiorgan failure, pancreatic necrosis, and mortality rates up to 20% in adults and 6.5% in children. OVERVIEW: We describe an infant who suffered from an episode of acute pancreatitis from severe hypertriglyceridemia. Two major challenges complicate the case: identifying the etiology of severe hypertriglyceridemia and finding an efficacious treatment. A thorough history, physical examination, and laboratory workup failed to identify a clear etiology, prompting a genetic workup that identified compound heterozygous mutations in the glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPIHBP1) gene. This patient's hypertriglyceridemia responded to an infant formula rich in medium chain triglycerides (MCTs), and she remained free of pancreatitis 6 months later. CONCLUSIONS: This case highlights the need to pursue a genetic evaluation in the absence of secondary causes of severe hypertriglyceridemia in infants. Patients with mutations in GPIHBP1 fail to respond to currently available lipid-lowering agents so dietary management-specifically, an extremely low-fat diet and supplementation with MCT-remains the cornerstone of therapy. Treatment in infants should focus on dietary measures rather than pharmacologic agents.

Planned place of birth in New Zealand: does it affect mode of birth and intervention rates among low-risk women?

BACKGROUND: Midwives providing care as lead maternity caregivers in New Zealand provide continuity of care to women who may give birth in a variety of settings, including home, primary units, and secondary and tertiary level hospitals. The purpose of this study was to compare mode of birth and intrapartum intervention rates for low-risk women planning to give birth in these settings under the care of midwives. METHODS: Data for a cohort of low-risk women giving birth in 2006 and 2007 were extracted from the Midwifery Maternity Provider Organisation database. Mode of birth, intrapartum interventions, and neonatal outcomes were compared with results adjusted for age, parity, ethnicity, and smoking. RESULTS: Women planning to give birth in secondary and tertiary hospitals had a higher risk of cesarean section, assisted modes of birth, and intrapartum interventions than similar women planning to give birth at home and in primary units. The risk of emergency cesarean section for women planning to give birth in a tertiary unit was 4.62 (95% CI: 3.66-5.84) times that of a woman planning to give birth in a primary unit. Newborns of women planning to give birth in secondary and tertiary hospitals also had a higher risk of admission to a neonatal intensive care unit (RR: 1.40, 95% CI: 1.05-1.87; RR: 1.78, 95% CI: 1.31-2.42) than women planning to give birth in a primary unit. CONCLUSIONS: Planned place of birth has a significant influence on mode of birth and rates of intrapartum intervention in childbirth.

Anticholinergic drugs, bladder retraining and their combination for urge urinary incontinence: a pilot randomised trial.

Bladder retraining and anticholinergic drugs in women with urge urinary incontinence need to be compared. Women with urge urinary incontinence were recruited by advertisements, from primary care and from a urogynaecology clinic. Women were randomised using a web page to bladder retraining, anticholinergic drugs or both and followed up at 3 and 12 months. No blinding was attempted. The primary outcomes were the trial process and the Overactive Bladder Questionnaire (OAB-q) quality-of-life measure. Recruitment was much slower than anticipated. There were no differences in the OAB-q at 12 months (87.9 SD 11.6 bladder retraining, 81.6 SD 19.3 drug therapy and 88.9 SD 9.9 combination) but dry mouth was more common in those taking drugs. It is feasible to run a pragmatic randomised trial with 12-month follow-up for women with urinary urge incontinence. This will require about 500 participants per arm.