Systematic review of first-in-human and early phase clinical trials for surgically implantable biological mitral valve substitutes.

BACKGROUND: The aim of this review was the creation of uniform protocols to carry out and disclose First-In-Human and preliminary clinical trials of biological mitral valve replacement. The need for consistent methodology in these early trials was highlighted by the observation of significant variability in the methods and protocols used across different research. METHODS: An extensive search through six major databases was carried out to retrieve First-In-Human (FIH) clinical studies evaluating surgically implanted bio-prostheses in the mitral position. RESULTS: Following the PRISMA guideline, a systematic search identified 2082 published articles until March 2023. After removing duplicates (189), 1862 citations were screened, resulting in 22 eligible studies with 3332 patients for analysis. The mitral valve prostheses in these studies ranged from 21 to 37 mm, with the 29 mm size being most prevalent. Patient numbers varied, with the FIH subgroup including 31 patients and the older subgroup including 163 patients. Average study durations differed: the older subgroup lasted 4.57 years, the FIH subgroup 2.85 years, and the early phase studies spanned 8.05 years on average. CONCLUSION: FIH clinical report is essential to assess the significance of clinical data required for a "de novo" surgical implant. In addition, understanding the performance of the device, and recognizing the difficulties associated with the innovation constitute important lessons. These insights could be beneficial for the development of bioprosthetic heart valves and formulating a protocol for an FIH clinical trial.

Multifaceted quality improvement initiative to decrease pediatric asthma readmissions.

BACKGROUND: Asthma is the most common chronic disease of childhood and a leading cause of hospitalization in children. A primary goal of asthma control is prevention of hospitalizations. A hospital admission is the single strongest predictor of future hospital admissions for asthma. The 30-day asthma readmission rate at our institution was significantly higher than that of other hospitals in the Children's Hospital Association. As a result, a multifaceted quality improvement project was undertaken with the goal of reducing the 30-day inpatient asthma readmission rate by 50% within two years. METHODS: Analysis of our institution's readmission patterns, value stream mapping of asthma admission, discharge, and follow-up processes, literature review, and examination of comparable successful programs around the United States were all utilized to identify potential targets for intervention. Interventions were implemented in a stepwise manner, and included increasing inhaler availability after discharge, modifying asthma education strategies, and providing in-home post-discharge follow-up. The primary outcome was a running 12-month average 30-day inpatient readmission rate. Secondary outcomes included process measures for individual interventions. RESULTS: From a peak of 7.98% in January 2013, a steady decline to 1.65% was observed by July 2014, which represented a 79.3% reduction in 30-day readmissions. CONCLUSION: A significant decrease in hospital readmissions for pediatric asthma is possible, through comprehensive, multidisciplinary quality improvement that spans the continuum of care.

Modeling, Simulation, and Implementation of Solar-Driven Water-Splitting Devices.

An integrated cell for the solar-driven splitting of water consists of multiple functional components and couples various photoelectrochemical (PEC) processes at different length and time scales. The overall solar-to-hydrogen (STH) conversion efficiency of such a system depends on the performance and materials properties of the individual components as well as on the component integration, overall device architecture, and system operating conditions. This Review focuses on the modeling- and simulation-guided development and implementation of solar-driven water-splitting prototypes from a holistic viewpoint that explores the various interplays between the components. The underlying physics and interactions at the cell level is are reviewed and discussed, followed by an overview of the use of the cell model to provide target properties of materials and guide the design of a range of traditional and unique device architectures.

Malassezia Pneumonia: A Rare Complication of Parenteral Nutrition Therapy.

Malassezia species (formerly known as Pityrosporum) are part of normal human skin flora and have been associated with benign dermatologic conditions, such as seborrheic dermatitis and tinea versicolor. In rare cases, however, Malassezia has been associated with systemic disease in immunocompromised patients and infants in the neonatal intensive care unit. Malassezia species require long-chain fatty acids for growth and therefore have a known predilection for individuals receiving lipid containing intravenous parenteral nutrition (PN). Systemic infections are characterized by prolonged fevers and illness but can include nonspecific signs and symptoms. We present the diagnosis and management of a rare case of an immunocompetent, nonneonatal, PN-dependent child with Malassezia furfur pneumonia.

The effect of varying stimulus phase between frequency and amplitude modulation on auditory steady-state responses in neonates.

OBJECTIVE: To compare auditory steady-state responses (ASSRs) to air-conducted amplitude, frequency, and mixed modulated stimuli (AM, FM, and MM, respectively) in neonates. DESIGN: Multiple ASSRs to AM, FM, and MM to 0.5, 1, 2, and 4 kHz tones modulated between 0.078 and 0.092 kHz were recorded and compared. MM phase settings across the cycle at 45° intervals were used and optimum phase settings were predicted using a sinusoidal model. STUDY SAMPLE: Twenty neonates with click ABR thresholds of ≤ 40 dB nHL. RESULTS: ASSR amplitudes were significantly larger to AM than FM stimuli. MM phase setting had a significant effect on amplitude at 1, 2, and 4 kHz but not 0.5 kHz. MM phase settings (± 95% confidence intervals) of 276° (± 9.5°) and 270° (± 19.1°) were predicted for 1 and 2 kHz, respectively. The 0.5 and 4 kHz data were not sufficient to model any effect of phase. MM and AM response latencies increased with decreasing carrier frequency. Some MM response latencies were significantly different from AM response latencies, however no consistent trend was apparent. Test times were significantly affected by phase setting. CONCLUSIONS: MM phase settings have a significant effect on ASSR response amplitude and latencies in neonates.

Effect of varying phase between frequency and amplitude modulation on bone conduction auditory steady state responses.

OBJECTIVES: Auditory steady state response (ASSR) testing provides a means to objectively estimate hearing levels in newborns and adults for whom behavioral tests prove difficult. When testing these patient groups, it is preferable that clear responses to both air and bone conduction stimuli are obtained in a short amount of time. Much of the literature addressing ASSRs, such as investigations of stimulus and recording parameters, have focused on air conduction ASSRs. The aim of this investigation was to study the amplitudes, latencies, and test times of bone conduction ASSRs elicited using amplitude- (AM), frequency- (FM), and mixed-modulated (MM) stimuli and provide suggestions for optimum recording parameters. DESIGN: Bone and air conduction multiple ASSRs were recorded from two groups of 20 normal-hearing adults using the Multiple Auditory Steady State Response research system. AM, FM, and MM sinusoidal tones were used (0.5-, 1-, 2-, and 4-kHz carrier frequencies), which were modulated between 78 and 92 Hz. AM depth was 100% and FM depth was 20%. ASSR amplitudes and latencies (calculated using the "preceding cycles" technique) were analyzed for MM phase settings across the cycle from 0° at 45° intervals and compared with AM responses. Optimum phase settings for bone and air conduction ASSRs were calculated using a sinusoidal model based on the amplitude data. RESULTS: Similar effects of stimulus type and carrier frequency were observed for bone and air conduction ASSRs. AM responses were larger in amplitude compared with FM responses. MM (at all phase settings tested) and AM response latencies increased with decreasing carrier frequency. MM phase setting had a significant (p < 0.01) sinusoidal effect on ASSR amplitudes, compared with AM responses, at 1, 2, and 4 kHz but not 0.5 kHz for air conduction and 1 and 2 kHz but not 0.5 and 4 kHz for bone conduction. Using a sinusoidal function to model this effect, MM phase settings (±95% confidence intervals) of 318° (295 to 350°) and 295° (290 to 310°) are predicted to evoke the largest responses for bone conduction ASSRs at 1 and 2 kHz, respectively. Phase settings of 293° (285 to 310°), 300° (280 to 310°), and 280° (255 to 330°) are predicted for air conduction ASSRs at 1, 2, and 4 kHz, respectively. MM phase setting had little effect on estimated latency. Test times were significantly (p < 0.01) affected by phase setting with both increases and decreases being observed. Test times for ASSRs at 1, 2, and 4 kHz could be significantly reduced if the estimated optimum phase settings are used. CONCLUSIONS: Different stimuli can significantly affect the amplitudes of bone conduction ASSRs. These effects are similar to those observed for air conduction ASSRs. MM stimuli with specific phase settings evoke larger bone conduction ASSRs compared with AM and FM stimuli alone, and calculations show that the time taken to obtain these responses is reduced. Implementation of the suggested optimum settings will promote efficient collection of bone conduction, and indeed air conduction, ASSR data.

Neonatal cochlear function: measurement after exposure to acoustic noise during in utero MR imaging.

PURPOSE: To establish whether fetal exposure to the operating noise of 1.5-T magnetic resonance (MR) imaging is associated with cochlear injury and subsequent hearing loss in neonates. MATERIALS AND METHODS: The study was performed with local research ethics committee approval and written informed parental consent. Neonatal hearing test results, including otoacoustic emission (OAE) data, were sought for all neonates delivered in Sheffield who had previously undergone in utero MR imaging between August 1999 and September 2007. The prevalence of hearing impairment in these neonates was determined, with corresponding 95% confidence intervals calculated by using the binomial exact method, and mean OAE measurements were compared with anonymized local audiometric reference data by using the t test. RESULTS: One hundred three neonates who had undergone in utero MR imaging were identified; 96 of them had completed hearing screening assessment. Thirty-four of these babies were admitted to the neonatal intensive care unit (NICU), and one of them had bilateral hearing impairment. The prevalence of hearing impairment was 1% (one of 96; 95% confidence interval: 0.03%, 5.67%), which is in accordance with the prevalence expected, given the high proportion of babies in this study who had been in the NICU (ie, NICU graduates). In addition, for the well babies, there was no significant difference in mean OAE cochlear response compared with that for a reference data set of more than 16,000 OAE results. When NICU graduates were included in the comparison, a significant difference (P = .002) was found in one of four frequency bands used to analyze the cochlear response; however, this difference was small compared with the normal variation in OAE measurements. CONCLUSION: The findings in this study provide some evidence that exposure of the fetus to 1.5-T MR imaging during the second and third trimesters of pregnancy is not associated with an increased risk of substantial neonatal hearing impairment.

An enteric-coated high-buffered pancrelipase reduces steatorrhea in patients with cystic fibrosis: a prospective, randomized study.

OBJECTIVE: Enteric-coated (EC) high-buffered (2.5 mEq [2.5 mmol] bicarbonate per capsule) pancrelipase microsphere enzymes were compared to EC-nonbuffered pancreatic enzymes for efficacy in reducing steatorrhea in patients with cystic fibrosis. DESIGN: Prospective, randomized, controlled trial using a crossover design with each subject as his/her own control. SUBJECTS/SETTING: Eighteen subjects with cystic fibrosis, who had pancreatic insufficiency and required large enzyme doses, were studied over two consecutive 7-day treatment periods. INTERVENTION: Each 7-day period consisted of 3 days at home followed by 4 days in a general clinical research center for careful control of diets, enzyme lipase doses (given at approximately 50% of the subject's usual lipase dose), and carmine red-labeled stool collections for 72-hour fecal fat balance studies. MAIN OUTCOME MEASURE: Fecal fat excretion. STATISTICAL ANALYSES PERFORMED: Differences in fat excretion, when each subject received EC-high-buffered pancrelipase vs EC-nonbuffered enzymes, were compared using linear modeling. RESULTS: Mean fat excretion decreased significantly in each subject during periods when given EC-high-buffered pancrelipase compared with periods when given EC-nonbuffered enzymes (fat excretion 18.2% vs 24.9% or fat absorption 81.8% vs 75.1%, respectively; P=0.01). Thirteen of 18 subjects (72%) excreted less fat when receiving EC-high-buffered pancrelipase whereas 10 (56%) decreased fat excretion by more than 5%, and five subjects did not respond. CONCLUSIONS: EC-high-buffered pancrelipase decreased fat excretion, symbolizing improved fat absorption, when compared with EC-nonbuffered pancreatic enzymes given at equivalent, reduced (approximately 50% of usual) lipase doses in nourished subjects with cystic fibrosis and mild pulmonary disease.

Tactile information transfer: a comparison of two stimulation sites.

Two experiments on the discrimination of time-varying tactile stimuli were performed, with comparison of stimulus delivery to the distal pad of the right index finger and to the right wrist (palmar surface). Subjects were required to perceive differences in short sequences of computer-generated stimulus elements (experiment 1) or differences in short tactile stimuli derived from a speech signal (experiment 2). The pulse-train stimuli were distinguished by differences in frequency (i.e., pulse repetition rate) and amplitude, and by the presence/absence of gaps (approximately 100-ms duration). Stimulation levels were 10 dB higher at the wrist than at the fingertip, to compensate for the lower vibration sensitivity at the wrist. Results indicate similar gap detection at wrist and fingertip and similar perception of frequency differences. However, perception of amplitude differences was found to be better at the wrist than at the fingertip. Maximum information transfer rates for the stimuli in experiment 1 were estimated at 7 bits s(-1) at the wrist and 5 bits s(-1) at the fingertip.

Must the bearer of a right have the concept of that to which he has a right?

KIE: Stevens critiques what he calls the "conceptual possession requirement" as defined by Michael Tooley in his article, "Abortion and infanticide," Philosophy and Public Affairs 1972 Fall; 2(1): 37-65. Tooley argued that a being has a right to something only if it has the concept of that thing. He claimed that fetuses and infants do not have a serious right to life because they have no concept of a continuing self, and that therefore abortion and infanticide are morally permissible. Stevens contends that the conceptual possession requirement is not valid, offers a counterexample to Tooley's argument, and defends his reasoning against what he presumes might be Tooley's counterarguments.^ieng