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Reply to: Random interstratification in hydrated graphene oxide membranes and implications for seawater desalination. NATURE NANOTECHNOLOGY 2022; 17:134-135. [PMID: 35058652 DOI: 10.1038/s41565-021-01067-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 11/30/2021] [Indexed: 06/14/2023]
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Integrating neuroimaging biomarkers into the multicentre, high-dose erythropoietin for asphyxia and encephalopathy (HEAL) trial: rationale, protocol and harmonisation. BMJ Open 2021; 11:e043852. [PMID: 33888528 PMCID: PMC8070884 DOI: 10.1136/bmjopen-2020-043852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
INTRODUCTION MRI and MR spectroscopy (MRS) provide early biomarkers of brain injury and treatment response in neonates with hypoxic-ischaemic encephalopathy). Still, there are challenges to incorporating neuroimaging biomarkers into multisite randomised controlled trials. In this paper, we provide the rationale for incorporating MRI and MRS biomarkers into the multisite, phase III high-dose erythropoietin for asphyxia and encephalopathy (HEAL) Trial, the MRI/S protocol and describe the strategies used for harmonisation across multiple MRI platforms. METHODS AND ANALYSIS Neonates with moderate or severe encephalopathy enrolled in the multisite HEAL trial undergo MRI and MRS between 96 and 144 hours of age using standardised neuroimaging protocols. MRI and MRS data are processed centrally and used to determine a brain injury score and quantitative measures of lactate and n-acetylaspartate. Harmonisation is achieved through standardisation-thereby reducing intrasite and intersite variance, real-time quality assurance monitoring and phantom scans. ETHICS AND DISSEMINATION IRB approval was obtained at each participating site and written consent obtained from parents prior to participation in HEAL. Additional oversight is provided by an National Institutes of Health-appointed data safety monitoring board and medical monitor. TRIAL REGISTRATION NUMBER NCT02811263; Pre-result.
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A generative co-design framework for healthcare innovation: development and application of an end-user engagement framework. RESEARCH INVOLVEMENT AND ENGAGEMENT 2021; 7:12. [PMID: 33648588 PMCID: PMC7923456 DOI: 10.1186/s40900-021-00252-7] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 01/15/2021] [Indexed: 05/31/2023]
Abstract
Background Continual improvements to health systems, products, and services are necessary for improvements in health. However, many of these improvements are not incorporated into everyday practice. When designing new health systems, products, and services, involving members of the healthcare community and the public with personal healthcare experience can help to make sure that improvements will be useful and relevant to others like them. Methods Together with healthcare workers and family members with healthcare experience, we developed and applied a step-by-step guide to involving those with personal experience in the design of health system improvements. Results Our guide has three phases- 'Pre-Design', 'Co-Design', and 'Post-Design'. This paper describes each of these phases and illustrates how we applied them to our own project, which is to use virtual healthcare methods to improve care for children with chronic healthcare conditions and their families. In our own work, we found that healthcare workers and family members with personal healthcare experiences were able to use their knowledge and creativity to help us imagine how to improve care for children with chronic healthcare conditions and their families. We have created action items from these family member- and healthcare worker-identified needs, which we will use to shape our virtual healthcare system. Conclusions This paper may be useful for those seeking to involve members of the healthcare community and the public in the creation of better healthcare systems, products, and services. Background Challenges with the adoption, scale, and spread of health innovations represent significant gaps in the evidence-to-practice cycle. In the health innovation design process, a lack of attention paid to the needs of end-users, and subsequent tailoring of innovations to meet these needs, is a possible reason for this deficit. In the creative field of health innovation, which includes the design of healthcare products, systems (governance and organization mechanisms), and services (delivery mechanisms), a framework for both soliciting the needs of end-users and translating these needs into the design of health innovations is needed. Methods To address this gap, our team developed and applied a seven-step methodological framework, called A Generative Co-Design Framework for Healthcare Innovation. This framework was developed by an interdisciplinary team that included patient partners. Results This manuscript contributes a framework and applied exemplar for those seeking to engage end-users in the creative process of healthcare innovation. Through the stages of 'Pre-Design', 'Co-Design', and 'Post-Design', we were able to harness the creative insights of end-users, drawing on their experiences to shape a future state of care. Using an expository example of our own work, the DigiComp Kids project, we illustrate the application of each stage of the Framework. Conclusions A Generative Co-Design Framework for Healthcare Innovation provides healthcare innovators, applied health science researchers, clinicians, and quality improvement specialists with a guide to eliciting and incorporating the viewpoints of end-users while distilling practical considerations for healthcare innovation and design.
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Respiratory syncytial virus (RSV) infection in children with medical complexity. Eur J Clin Microbiol Infect Dis 2018; 38:171-176. [PMID: 30374685 DOI: 10.1007/s10096-018-3409-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Accepted: 10/17/2018] [Indexed: 10/28/2022]
Abstract
Children with medical complexity (CMC) are vulnerable to respiratory illness hospitalization (RIH) and respiratory syncytial virus (RSV)-related hospitalization (RSVH) due to multisystem disorders and compromised airways. It is unknown whether RSV prophylaxis is effective, or if RSVH is associated with significant morbidities in CMC. The study objectives were to (1) determine the incidence of RSV-related infection in prophylaxed CMC during the first 3 years of life and (2) assess the burden of illness following RSVH. A single tertiary center, retrospective study, was conducted of CMC who received palivizumab during the 2012-2016 RSV seasons. Fifty-four subjects were enrolled; most received one (38.9%, n = 21) or two (57.4%, n = 31) seasons of prophylaxis (mean = 4.2 [SD = 1.24], palivizumab doses per season). The cohort comprised children with multiple medical conditions (n = 22, 40.8%), tracheostomy (n = 18, 33.3%), and invasive (n = 10, 18.5%) or non-invasive (n = 4, 7.4%) ventilation. Of the CMC, 24 were hospitalized 47 times for a viral-related respiratory illness. RSV incidence in the first 3 years of life was 7.4%. Viral-related RIH and RSVH rates were 44.4% (n = 24/54) and 1.9% (n = 1/54), respectively. Of the four RSV-positive children, one was ventilated for 9 days, two acquired nosocomial RSV that was managed on the ward, and one was discharged home under close complex care supervision. All four RSV-positive cases required additional oxygen during their illness. CMC experience a high viral-related RIH rate and palivizumab likely minimizes RSV-related events and associated morbidities. The efficacy of palivizumab in CMC, especially in those ≤ 3 years, should be prospectively evaluated.
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Why different water models predict different structures under 2D confinement. J Comput Chem 2018; 39:2051-2059. [PMID: 30226923 DOI: 10.1002/jcc.25369] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 05/04/2018] [Accepted: 05/11/2018] [Indexed: 01/23/2023]
Abstract
Experiments of nanoconfined water between graphene sheets at high pressure suggest that it forms a square ice structure (Algara-Siller et al., Nature, 2015, 519, 443). Molecular dynamics (MD) simulations have been used to attempt to recreate this structure, but there have been discrepancies in the structure formed by the confined water depending on the simulation set-up that was employed and particularly on the choice of water model. Here, using classical molecular dynamics simulations, we have systematically investigated the effect that three different water models (SPC/E, TIP4P/2005 and TIP5P) have on the structure of water confined between two rigid graphene sheets with a 0.9 nm separation. We show that the TIP4P/2005 and the TIP5P water models form a hexagonal AA-stacked structure, whereas the SPC/E model forms a rhombic AB-stacked structure. Our work demonstrates that the formation of these structures is driven by differences in the strength of hydrogen bonds predicted by the three water models, and that the nature of the graphene/water interaction only mildly affects the phase diagram. Considering the available experimental data and first-principle simulations we conclude that, among the models tested, the TIP4P/2005 and TIP5P force fields are for now the most reliable when simulating water under confinement. © 2018 Wiley Periodicals, Inc.
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Primary Results of the Multicenter ARISE II Study (Analysis of Revascularization in Ischemic Stroke With EmboTrap). Stroke 2018; 49:1107-1115. [DOI: 10.1161/strokeaha.117.020125] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Revised: 02/05/2018] [Accepted: 02/26/2018] [Indexed: 02/04/2023]
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Abstract
The constantly widening industrial applications of carbon-based nanomaterials puts into sharp perspective the lack of true solvents in which the materials spontaneously exfoliate to individual molecules. This work shows that the different geometry of graphene compared to that of carbon nanotubes can change the potency of a molecule to act as a solvent or dispersant. Through analysis of the structure/function relationships, we derive a number of design rules that will aid the identification of the best solvent or dispersant candidates.
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Tunable sieving of ions using graphene oxide membranes. NATURE NANOTECHNOLOGY 2017; 12:546-550. [PMID: 28369049 DOI: 10.1038/nnano.2017.21] [Citation(s) in RCA: 728] [Impact Index Per Article: 104.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 02/02/2017] [Indexed: 05/20/2023]
Abstract
Graphene oxide membranes show exceptional molecular permeation properties, with promise for many applications. However, their use in ion sieving and desalination technologies is limited by a permeation cutoff of ∼9 Å (ref. 4), which is larger than the diameters of hydrated ions of common salts. The cutoff is determined by the interlayer spacing (d) of ∼13.5 Å, typical for graphene oxide laminates that swell in water. Achieving smaller d for the laminates immersed in water has proved to be a challenge. Here, we describe how to control d by physical confinement and achieve accurate and tunable ion sieving. Membranes with d from ∼9.8 Å to 6.4 Å are demonstrated, providing a sieve size smaller than the diameters of hydrated ions. In this regime, ion permeation is found to be thermally activated with energy barriers of ∼10-100 kJ mol-1 depending on d. Importantly, permeation rates decrease exponentially with decreasing sieve size but water transport is weakly affected (by a factor of <2). The latter is attributed to a low barrier for the entry of water molecules and large slip lengths inside graphene capillaries. Building on these findings, we demonstrate a simple scalable method to obtain graphene-based membranes with limited swelling, which exhibit 97% rejection for NaCl.
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Abstract
At the graphene-electrolyte interface, the polarizability of both the surface and the solution plays a major role in defining the interfacial structure and dynamics of the ions. Current molecular models predict different ion adsorption behavior at the interface depending on whether surface or solution polarization is included in the model. Here, we propose a simple method to parametrize the ion-carbon interaction from density functional theory, implicitly modeling the solution using the conductor-like polarizable continuum model. The new model simultaneously takes into account the polarizability of both the graphene sheet and the solution without the need to use time-consuming polarizable potentials and can predict the ion adsorption trend so far only achievable using first-principles simulations. Simulations performed with 1 M electrolyte solutions of different ions show that cations are strongly adsorbed onto the graphene surface with a trend (Li+ < Na+ < K+) opposite to that predicted by the gas-phase calculations and different from that obtained from the single-ion simulations.
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Van der Waals pressure and its effect on trapped interlayer molecules. Nat Commun 2016; 7:12168. [PMID: 27385262 PMCID: PMC4941049 DOI: 10.1038/ncomms12168] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 06/08/2016] [Indexed: 12/30/2022] Open
Abstract
Van der Waals assembly of two-dimensional crystals continue attract intense interest due to the prospect of designing novel materials with on-demand properties. One of the unique features of this technology is the possibility of trapping molecules between two-dimensional crystals. The trapped molecules are predicted to experience pressures as high as 1 GPa. Here we report measurements of this interfacial pressure by capturing pressure-sensitive molecules and studying their structural and conformational changes. Pressures of 1.2±0.3 GPa are found using Raman spectrometry for molecular layers of 1-nm in thickness. We further show that this pressure can induce chemical reactions, and several trapped salts are found to react with water at room temperature, leading to two-dimensional crystals of the corresponding oxides. This pressure and its effect should be taken into account in studies of van der Waals heterostructures and can also be exploited to modify materials confined at the atomic interfaces.
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Clinical evaluation of single-shot and readout-segmented diffusion-weighted imaging in stroke patients at 3 T. Acta Radiol 2013; 54:299-306. [PMID: 23319722 DOI: 10.1258/ar.2012.120541] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND Diffusion-weighted imaging (DWI) magnetic resonance imaging (MRI) is most commonly performed utilizing a single-shot echo-planar imaging technique (ss-EPI). Susceptibility artifact and image blur are severe when this sequence is utilized at 3 T. PURPOSE To evaluate a readout-segmented approach to DWI MR in comparison with single-shot echo planar imaging for brain MRI. MATERIAL AND METHODS Eleven healthy volunteers and 14 patients with acute and early subacute infarctions underwent DWI MR examinations at 1.5 and 3T with ss-EPI and readout-segmented echo-planar (rs-EPI) DWI at equal nominal spatial resolutions. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) calculations were made, and two blinded readers ranked the scans in terms of high signal intensity bulk susceptibility artifact, spatial distortions, image blur, overall preference, and motion artifact. RESULTS SNR and CNR were greatest with rs-EPI (8.1 ± 0.2 SNR vs. 6.0 ± 0.2; P <10(-4) at 3T). Spatial distortions were greater with single-shot (0.23 ± 0.03 at 3T; P <0.001) than with rs-EPI (0.12 ± 0.02 at 3T). Combined with blur and artifact reduction, this resulted in a qualitative preference for the readout-segmented scans overall. CONCLUSION Substantial image quality improvements are possible with readout-segmented vs. single-shot EPI - the current clinical standard for DWI - regardless of field strength (1.5 or 3 T). This results in improved image quality secondary to greater real spatial resolution and reduced artifacts from susceptibility in MR imaging of the brain.
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Clinical Correlates of Autism Spectrum Disorder Symptoms in very Low Birthweight Infants. Paediatr Child Health 2009. [DOI: 10.1093/pch/14.suppl_a.53aa] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Abstract
An investigation was performed to identify methods suitable for decontamination of equipment being transferred from a facility contaminated with Syphacia muris to a new facility. Perianal samples were taken on clear sticky tape from rats known to be infected with S. muris. Tapes and attached worm eggs were treated with ethylene oxide, formaldehyde fumigation, potassium peroxysulphate, chlorine dioxide and didecyl di-methyl ammonium chloride, chlorine dioxide, alcohol/chlorhexidine, 100 degrees C dry heat for 30 min, ultraviolet light (UV), or left for 4 weeks at room temperature. The subsequent viability of the eggs was compared to untreated control samples. Heat and ethylene oxide produced a 100% kill rate of S. muris eggs. Formaldehyde gas and chlorine dioxide treatments showed marked effectiveness, with the number of eggs killed at 94% and 96%, respectively, while the other agents showed less efficacy (36-78% eggs killed). The percentage of eggs not hatching in the controls was 21%. Since so few agents were effective against S. muris eggs, care should be taken when choosing a method for decontaminating a facility.
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Evaluation of carotid stenosis by angiography: potential bias toward overestimated measurements introduced by prior interpretation of Doppler sonograms. AJNR Am J Neuroradiol 2000; 21:639-42. [PMID: 10782771 PMCID: PMC7976643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
BACKGROUND AND PURPOSE Doppler sonography of the carotid arteries is routinely performed before catheter angiography, and its results may bias the subsequent interpretation of angiograms. We attempt to establish that Doppler sonography may show an exaggerated degree of carotid stenosis, introducing bias to the evaluation of carotid stenosis by subsequent catheter angiography. METHODS Angiograms of the carotid arteries obtained to evaluate potential carotid stenosis in patients who had undergone Doppler sonography of the carotid arteries were retrospectively reviewed (from 1993 to 1998). Readers who were blinded to the previous interpretations of the angiography and Doppler sonography results measured carotid stenosis. The results of Doppler sonography of the carotid arteries were not re-evaluated. Based on the original Doppler sonograms, stenoses were categorized as normal/mild (<30%), moderate (30-59%), severe (60-79%), and critical (80-99%). Within these categories, the differences between the original percent stenosis, as determined by angiography, and the blinded measurements were determined. RESULTS A total of 106 patients with angiographically measurable stenoses in 128 vessels were identified. The difference between the blinded readers was 3% (+/-8%), with no category statistically different from the other. The difference between original and remeasured stenoses in carotid arteries in the Doppler categories were as follows: mild stenosis, 2% (+/-9%); moderate stenosis, 6% (+/-15%); severe stenosis, 8% (+/-15%); and critical stenosis, 22% (+/-12%). A significant overestimation occurred in the severe (P < .05) and critical (P < .0001) stenosis categories. One third of patients with stenoses in the severe or critical Doppler category had significant stenoses on the original angiograms that were less than 60%, according to blinded remeasurement. CONCLUSION Doppler sonography of the carotid arteries has the potential to bias the subsequent interpretation of catheter angiography. Care must be taken to measure stenosis accurately, using strict criteria to determine the potential benefit of carotid endarterectomy for the individual patient and to ensure that the criteria for Doppler sonography of the carotid arteries are based on accurate catheter angiography measurements.
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Students' reactions to ASHP MCM. American Society of Health-System Pharmacists. Midyear Clinical Meeting. Am J Health Syst Pharm 1999; 56:1991. [PMID: 10554922 DOI: 10.1093/ajhp/56.19.1991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Bacterial counts in canine duodenal fluid after exposure to saline, sodium bicarbonate and hypertonic dextrose solutions used to maintain patency of chronically implanted catheters. Lab Anim 1999; 33:143-8. [PMID: 10780817 DOI: 10.1258/002367799780578336] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Flushing of intestinal vascular access ports (VAPs) is commonly performed to prevent the problems of blockage and infection, and in this study four different flushing solutions were compared. The growth of bacteria from canine duodenal contents was compared in: 0.9% saline, 50% dextrose, 8.4% sodium bicarbonate (NaHCO3) and 0.01 M phosphate buffered saline (PBS). Duodenal contents from three laboratory beagles were serially diluted in these four solutions, spread plated onto agar at 24 h periods for 7 days and bacterial counts were performed. Immediately after the duodenal juices were added, no significant differences could be seen in bacterial counts with any of the solutions. Over the 7 day period, bacterial numbers greatly increased in saline and phosphate buffered saline, but greatly decreased in dextrose and sodium bicarbonate solutions. Dextrose and sodium bicarbonate appeared to be the most promising flushing solutions tested to minimize infections of associated intestinal VAPs.
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Abstract
Two babies were smothered by their baby-sitter. The deaths happened 4 years apart. The baby-sitter was convicted based on a confession, not on the findings at autopsy. These cases illustrate the difficulty in distinguishing SIDS from suffocation homicide.
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Neurotrophin-3- and norepinephrine-mediated adrenergic differentiation and the inhibitory action of desipramine and cocaine. JOURNAL OF NEUROBIOLOGY 1997; 32:262-80. [PMID: 9058320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In the presence of neurotrophin-3 (NT-3), high-affinity norepinephrine (NE) uptake by quail neural crest cells was significantly increased as judged by in vitro colony assay of adrenergic differentiation. In the presence of the related neurotrophins nerve growth factor (NGF) or brain-derived neurotrophic (BDNF) factor, or of basic fibroblast growth factor (bFGF), there were no significant changes. When NE was added to the culture medium in addition to NT-3, more colonies contained dopamine-beta-hydroxylase (DBH)-immunoreactive cells, an enzyme that is characteristic for adrenergic cells. The NE-mediated increase in the portion of colonies that contained DBH-immunoreactive cells was prevented by the tricyclic antidepressant desipramine (DMI) and by cocaine, two types of drug that block cellular transport of NE. To further examine whether NE acts via uptake, colony assays were performed in the presence and absence of adrenergic antagonists and agonists. These would be expected to mimic the DMI and NE effects, respectively, if the mechanism of action involved activation of adrenergic autoreceptors. Neither class of drug showed a detectable effect within a wide range of concentrations. Immunocytochemistry using antibodies against beta 1 and beta 2 adrenergic receptors further supported the notion that DMI action and beta-receptor expression are not causally related. Ratio imaging was subsequently used in an attempt to elucidate the mechanism of NE action. Within a few minutes of addition of NE to the culture medium, there was an increase in intracellular free calcium in a subset of neural crest cells. Taken together, our data indicate that NT-3 is involved in the appearance of the NE transporter (NET) during embryonic development; internalized NE directly or indirectly increases adrenergic differentiation as measured by immunoreactivity of the adrenergic biosynthetic enzyme DBH; and norepinephrine uptake inhibitors have treatogenic potential.
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Abstract
BACKGROUND We prospectively studied the recovery of gastrointestinal motility in patients undergoing laparoscopic (LAP, n = 7) or open (OPEN, n = 7) colon resections. METHODS At operation, bipolar recording electrodes were placed on the proximal and distal antrum, the proximal site of the colonic anastomosis, and the rectosigmoid for postoperative myoelectric recordings. RESULTS Shorter postoperative hospitalization and earlier resumption of a regular diet of the LAP group just barely failed to achieve significant differences when compared with the OPEN group (p = 0.091, p = 0.050, respectively). There were no differences between groups for slow wave frequency, amplitude, or dysrhythmias in the antrum, nor for return of discrete (DERA) and continuous (CERA) electrical response activity in the colon. Percentage of slow waves with spike activity tended to increase with passage of time postoperatively in both groups. There was a significant difference between POD 3 and 7+ in the LAP group (p < 0.05). However, there were no significant differences in the percentage of slow waves with spike activities between groups on any postoperative day. CONCLUSIONS The potential benefits of using a laparoscopic approach to colon resection are not clearly confirmed by these data. While such an approach may possibly result in shorter hospitalization, it appears to offer at best only modest increases in the rapidity of recovery of gastrointestinal function.
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Abstract
The first 1000 patients undergoing laparoscopic cholecystectomy (LC) at our institution were reviewed to investigate the impact of previous abdominal surgery on LC. The 454 patients having no previous abdominal surgery (NS) were compared to the 541 patients who had previous surgery (PS). PS patients were older, more likely to be female, and had a higher ASA risk category. PS patients had a higher incidence of wound infection, but in all other parameters of outcome, including operative duration and completion, length of hospitalization, and morbidity, there were no significant differences between PS and NS. When PS patients with previous upper abdominal surgery (PUAS, n = 59) were separately compared to the remainder of the entire patient group (NUAS, n = 936), the PUAS group was found to be older, to be more likely to be male, and to have a higher ASA risk category. PUAS patients had a longer postoperative hospitalization, and an increased incidence of intraoperative, postoperative, and total complications, readmissions to the hospital, and unrelated deaths. We conclude previous lower abdominal surgery has little impact on the outcome of patients undergoing LC while previous upper abdominal surgery is associated with increased morbidity.
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Abstract
We compared the results of concurrently performed laparoscopic versus open appendectomy as treatments for suspected acute appendicitis. The 68 laparoscopic procedures resulted in 62 appendectomies, 47 by the laparoscopic (LA) technique and 15 by the open (LO) technique. Another 54 patients underwent open appendectomy (OA). Significantly more females underwent laparoscopy (LA and LO: 52% versus OA: 33%, p = 0.047). Operative duration was shortest for OA (81 +/- 3 minutes), which was shorter than for LO (108 +/- 7 minutes), but not different than LA (86 +/- 6 minutes). The postoperative length of stay was not different for LA (3.5 +/- 0.5 days) compared with OA (5.9 +/- 1.6 days) or LO (4.8 +/- 1.3 days). One death occurred in the OA group. Wound complication rates were not significantly different for LA (4.3%) compared with OA (9.4%) and LO (13.3%). Overall complication rates were lower for LA (10.6%) and OA (18.9%) compared with LO (46.7%, p < 0.01). Median hospital cost for LO ($10,425) was higher (p < 0.02) than for either LA ($5,899) or OA ($5,220). When appendicitis was not present, definitive confirmation of pathology was achieved in 9 of 18 patients undergoing LA versus 4 of 14 patients having OA (p = not significant). We conclude that when laparoscopy and laparoscopic appendectomy can be performed, the procedure is safe and produces results comparable with those of open appendectomy without significant overall cost differences.
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A naphthyl analog of the aminostyryl pyridinium class of potentiometric membrane dyes shows consistent sensitivity in a variety of tissue, cell, and model membrane preparations. J Membr Biol 1992; 130:1-10. [PMID: 1469705 DOI: 10.1007/bf00233734] [Citation(s) in RCA: 123] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The fast potentiometric indicator di-4-ANEPPS is examined in four different preparations: lipid vesicles, red blood cells, squid giant axon, and guinea pig heart. The dye gives consistent potentiometric responses in each of these systems, although some of the detailed behavior varies. In lipid vesicles, the dye displays an increase in fluorescence combined with a red shift of the excitation spectrum upon hyperpolarization. Similar behavior is found in red cells where a dual wavelength radiometric measurement is also demonstrated. The signal-to-noise ratio of the potentiometric fluorescence response is among the best ever recorded on the voltage-clamped squid axon. The dye is shown to be a faithful and persistent monitor of cardiac action potentials with no appreciable loss of signal or deterioration of cardiac activity for periods as long as 2 hr with intermittent illumination every 10 min. These results, together with previously published applications of the dye to a spherical lipid bilayer model and to cells in culture, demonstrate the versatility of di-4-ANEPPS as a fast indicator of membrane potential.
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Abstract
An investigation was undertaken to determine whether hospital charges for laparoscopic cholecystectomy are higher than those for traditional open cholecystectomy. Thirty consecutive cases of successfully completed laparoscopic procedures in a single surgeon's experience were compared to 30 open cases performed within the previous calendar year. Patients undergoing open cholecystectomy were excluded if coexisting medical problems or complications prolonged hospitalization beyond 7 days. Mean patient age was comparable (open cholecystectomy = 47.3 +/- 2.9, laparoscopic cholecystectomy = 46.5 +/- 2.7 years), as was the incidence of other significant medical problems. Average duration of hospitalization was significantly longer for open cholecystectomy (3.6 = 0.2 days) than for laparoscopic cholecystectomy (1.0 +/- days, p less than .001). Average hospital charges for open cholecystectomy were $5606 +/- 496 and for laparoscopic cholecystectomy $4726 +/- 98. Hospital charges from operating room and recovery room charges alone were $2684 +/- 131 for laparoscopic cholecystectomy and $2196 +/- 113 for open cholecystectomy. These operating room charges represent a significantly higher percentage of total hospital charges for laparoscopic cholecystectomy than open cholecystectomy patients (laparoscopic cholecystectomy = 56.3 +/- 1.9%, open cholecystectomy = 41.2 +/- 1.5%, p less than .05). Average time for return to work or normal activity was significantly shorter for laparoscopic cholecystectomy 8.6 +/- 9 days) than for open cholecystectomy (32.4 +/- 3.6 days, p less than .001). The authors conclude that laparoscopic cholecystectomy is a cost effective procedure for the treatment of symptomatic cholelithiasis, and that increased operative costs more than offset the significantly decreased length of hospitalization.
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Abstract
The authors' experience with laparoscopic cholecystectomy (LC) in obese (O, n = 96) and morbidly obese (MO, n = 27) patient groups was compared with that in the normal weight (NW, n = 174) group of patients as well as the whole group (WG). There were no operative deaths. There were no significant differences between groups for any of the following: successful intraoperative cholangiography (WG, 52.2%; NW, 52.9%; O, 51.1%; MO, 55.6%), conversion to open cholecystectomy (WG, 9.6%; NW, 9.2%; O, 10.4%; MO, 11.1%), incidence of major complications (WG, 4.1%; NW, 3.4%, O, 5.2%; MO, 0%), incidence of minor complications (WG, 7.4%, NW, 7.5%; O, 6.3%; MO, 3.7%), and length of hospitalization after successful LC (WG, 1.25 days; NW, 1.31 days; O, 1.16 days; MO, 1.13 days). Duration of operation did not differ except LC in the MO group (136.4 +/- 6.9 minutes) was longer when compared with NW patients (123.0 +/- 2.9 minutes, p less than 0.05). The authors conclude LC is a safe and effective treatment for obese patients with symptomatic cholelithiasis.
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Abstract
The impact of introducing laparoscopy as part of the overall gastrointestinal endoscopy case load performed by residents was reviewed. During 1990, there was a significant increase (56.9%) in the number of flexible diagnostic endoscopic procedures performed compared with 1989. When the total number of laparoscopic procedures was considered, the increase was 117%. Residents participated in the "surgeon's" position in 59% of the therapeutic laparoscopic procedures and as either surgeon or "first assistant" in 86% of all therapeutic laparoscopic procedures and 94% of all diagnostic laparoscopic procedures. Complication rates for diagnostic laparoscopic procedures were low in 1989 (0.03%) and 1990 (0.2%). Complication rates for therapeutic laparoscopic procedures were also low (4%). There was no difference in the complication rate for cases in which residents were in the surgeon's position (4%) versus cases in which they were not (4%). Introduction of laparoscopic procedures into a surgical residency program can be done safely, especially in cases in which an established program in endoscopy exists.
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A case of fatal hemorrhage caused by intestinal histoplasmosis. Am J Gastroenterol 1991; 86:910-2. [PMID: 2058638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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28
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Abstract
Our initial experience with laparoscopic cholecystectomy (LC) for symptomatic cholelithiasis has involved 152 patients. Patient age ranged from 17 to 83 years; most were female (78%). Their average weight was 170 pounds (range, 75 to 365 lbs.). Twenty-two per cent had a single gallstone, while 9% had two to three stones and 64% had more than three stones. Exclusion criteria initially included upper abdominal scarring, severe acute cholecystitis, choledocholithiasis, and inability to tolerate general anesthesia. The first two of these are now only relative contraindications with increased experience. Thirteen of the one hundred fifty-two procedures (8.5%) required conversion to an open operation. Average time of operation was 138 minutes. Intraoperative cholangiography was attempted in 78% of cases and was completed successfully in 66% of those attempted. There have been no deaths. The complication rate has been low: 4% major, 0% life-threatening, and 7.2% minor complications. Postoperative analgesic requirements are remarkably low: 36% of patients required no narcotics after leaving the recovery room. Eighty-seven per cent of patients successfully undergoing LC were discharged by the first postoperative day. Most patients resumed normal activities within 1 week after discharge. Laparoscopic cholecystectomy offers the majority of patients with symptomatic cholelithiasis an improved treatment option, resulting in significantly less postoperative pain, hospitalization, and recuperation time.
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A unique case of congenital bilateral absence of parietal bones in a neonate. J Forensic Sci 1991; 36:593-8. [PMID: 2066733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The remains of an unidentified female neonate were discovered in a field in central Missouri. Examination revealed bilateral absence of the parietal bones. A search of the literature describing similar defects suggests that the present case represents a unique condition, described here for the first time.
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Unusual problems for the physician in managing a hospital patient who received a malicious insulin overdose. Neurosurgery 1985; 17:992-6. [PMID: 3908967 DOI: 10.1227/00006123-198512000-00023] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
A patient recovering normally from a biopsy and subtotal removal of a malignant brain tumor became severely hypoglycemic on the ward and died. The differential diagnosis eliminated disease as a possible cause, and medication error on the floor was also ruled out. Deliberate administration of a massive dose of insulin intravenously seemed to be the only alternative. A careful investigation supported the likelihood of a criminal act. The patient's wife came under suspicion and was subsequently arrested, charged with murder, and convicted. This sequence of events created three problems that fell outside of our normal professional training and experience as physicians. First, we were slow to suspect foul play in our search for an unusual cause. Second, the steps taken to protect the patient against further risk without denying reasonable rights to family or arousing the suspect's suspicions needed strengthening. Third, even though the occurrence of these events in a hospital allowed an unusual degree of evidence documenting the allegations to be accumulated, key parts of the evidence could not be used. The routine hospital handling of laboratory tests critical to support of the accusations was not sufficient to meet the demands of the legal system, which has its own criteria. We discuss the issues in managing these problems.
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Missouri's medical examiner-coroner system. MISSOURI MEDICINE 1984; 81:329-30. [PMID: 6738486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Pedestrian skills training for mentally retarded adults: comparison of training in two settings. MENTAL RETARDATION 1983; 21:107-110. [PMID: 6621349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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Additions and Corrections: Restricted Rotation in Aryl Amines. XXI. Effect of 3-Substituents on the Optical Stability of Some N-Benzenesulfonyl-N-carboxy-methylmesidines. J Am Chem Soc 1959. [DOI: 10.1021/ja01533a612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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34
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The Payment of Railway Fares. West J Med 1887. [DOI: 10.1136/bmj.2.1387.268-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Payment of Travelling Expenses of Branch Representatives on the Council of the Association. West J Med 1887. [DOI: 10.1136/bmj.1.1372.850-b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Payment of Travelling Expenses of the Representatives of the Branches to the Meetings of the Council. West J Med 1885. [DOI: 10.1136/bmj.2.1282.180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Payment of Travelling Expenses of the Representatives of the Branches to the Meetings of the Council. West J Med 1885. [DOI: 10.1136/bmj.2.1281.123-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Payment of Travelling Expenses of the Representatives of the Branches to the Meetings of Council. West J Med 1884. [DOI: 10.1136/bmj.2.1229.143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Two Cases of Aneurism, one of the Carotid and one of the Femoral Artery, Treated Successfully by the Wire Compress. BRITISH MEDICAL JOURNAL 1875; 2:551-4. [PMID: 20748004 DOI: 10.1136/bmj.2.774.551-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Mr. Syme and Acupressure. West J Med 1866. [DOI: 10.1136/bmj.1.263.56-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Carotid Aneurism and the Wire-Compress. West J Med 1865. [DOI: 10.1136/bmj.2.259.646-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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The Association, the Poor-Law Bill, &c. West J Med 1860. [DOI: 10.1136/bmj.s4-1.173.311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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The Association and the Journal. West J Med 1860. [DOI: 10.1136/bmj.s4-1.172.294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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The Association and the Journal. West J Med 1860. [DOI: 10.1136/bmj.s4-1.170.255-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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The Association and the Journal. West J Med 1860. [DOI: 10.1136/bmj.s4-1.168.216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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The Finances of the Association. West J Med 1860. [DOI: 10.1136/bmj.s4-1.158.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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The Journal: The Financial Condition of the Association. West J Med 1859. [DOI: 10.1136/bmj.s4-1.151.948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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48
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The Journal. West J Med 1859. [DOI: 10.1136/bmj.s4-1.149.900-c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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