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BACKGROUND: Jimsonweed (Datura stramonium) contains toxic alkaloids that cause gastrointestinal and central nervous system symptoms when ingested. This can be lethal at high doses. The plant may grow together with leguminous crops, mixing with them during harvesting. On 13 March 2019, more than 200 case-patients were admitted to multiple health centres for acute gastrointestinal and neurologic symptoms. We investigated to determine the cause and magnitude of the outbreak and recommended evidence-based control and prevention measures. METHODS: We defined a suspected case as sudden onset of confusion, dizziness, convulsions, hallucinations, diarrhoea, or vomiting with no other medically plausible explanations in a resident of Napak or Amudat District from 1 March-30 April 2019. We reviewed medical records and canvassed all villages of the eight affected subcounties to identify cases. In a retrospective cohort study conducted in 17 villages that reported the earliest cases, we interviewed 211 residents about dietary history during 11-15 March. We used modified Poisson regression to assess suspected food exposures. Food samples underwent chemical (heavy metals, chemical contaminants, and toxins), proteomic, DNA, and microbiological testing in one national and three international laboratories. RESULTS: We identified 293 suspected cases; five (1.7%) died. Symptoms included confusion (62%), dizziness (38%), diarrhoea (22%), nausea/vomiting (18%), convulsions (12%), and hallucinations (8%). The outbreak started on 12 March, 2-12 h after Batch X of fortified corn-soy blend (CSB +) was distributed. In the retrospective cohort study, 66% of 134 persons who ate CSB + , compared with 2.2% of 75 who did not developed illness (RRadj = 22, 95% CI = 6.0-81). Samples of Batch X distributed 11-15 March contained 14 tropane alkaloids, including atropine (25-50 ppm) and scopolamine (1-10 ppm). Proteins of Solanaceae seeds and Jimsonweed DNA were identified. No other significant laboratory findings were observed. CONCLUSION: This was the largest documented outbreak caused by food contamination with tropane alkaloids. Implicated food was immediately withdrawn. Routine food safety and quality checks could prevent future outbreaks.
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Datura stramonium , Brotes de Enfermedades , Humanos , Proteómica , Estudios Retrospectivos , Uganda/epidemiologíaRESUMEN
CONTEXT: On February 3, 2019, Atlanta, Georgia, hosted Super Bowl LIII, which is classified as a National Special Security Event. The festivities comprising this major sporting event brought approximately half a million people to Atlanta, which posed significant challenges to the local public health community. As the lead local agency for public health planning, preparedness, and response efforts, Fulton County Board of Health (FCBOH) needed to address multiple specific tasks based on core functional areas outlined in the Emergency Support Function (ESF) 8 (eg, bioterrorism preparedness and epidemiological surveillance). PROGRAM: To prepare for the Super Bowl, FCBOH developed a systematic approach to ensure community-wide public health preparedness for mass gatherings. This approach came to be known as the 6 E framework, which consists of (1) engaging stakeholders, (2) examining current capabilities and identifying gaps, (3) establishing roles and responsibilities, (4) executing plans to fill gaps, (5) exercising plans, and (6) evaluating impact. IMPLEMENTATION: We define each step of the 6 E framework and present practical examples of how FCBOH implemented each step when preparing for the Super Bowl. Challenges that FCBOH faced and the lessons learned in the process are illustrated. The 6 E framework provides a systematic approach to community preparedness and allows local health departments to tailor the approach to serve local public health needs. EVALUATION: The successful implementation of the 6 E framework allowed for stakeholders at the federal, state, and local levels (including law enforcement) to effectively coordinate an epidemiological investigation and response when 4 staff members reported gastrointestinal symptoms after eating at a feeding station. DISCUSSION: Preparation for the Super Bowl required months of diligent cross-sectoral and cross-jurisdictional partnership building, and the 6 E framework can help other local public health jurisdictions prepare to host major mass gatherings.
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Planificación en Desastres , Salud Pública , Georgia , Planificación en Salud , Humanos , Medidas de Seguridad , Estados UnidosRESUMEN
Semiconductor nanostructures with photocatalytic activity have the potential for many applications including remediation of environmental pollutants and use in antibacterial products. An effective way for promoting photocatalytic activity is depositing noble metal nanoparticles (NPs) on a semiconductor. In this paper, we demonstrated the successful deposition of Au NPs, having sizes smaller than 3 nm, onto ZnO NPs. ZnO/Au hybrid nanostructures having different molar ratios of Au to ZnO were synthesized. It was found that Au nanocomponents even at a very low Au/ZnO molar ratio of 0.2% can greatly enhance the photocatalytic and antibacterial activity of ZnO. Electron spin resonance spectroscopy with spin trapping and spin labeling was used to investigate the enhancing effect of Au NPs on the generation of reactive oxygen species and photoinduced charge carriers. Deposition of Au NPs onto ZnO resulted in a dramatic increase in light-induced generation of hydroxyl radical, superoxide and singlet oxygen, and production of holes and electrons. The enhancing effect of Au was dependent on the molar ratio of Au present in the ZnO/Au nanostructures. Consistent with these results from ESR measurements, ZnO/Au nanostructures also exhibited enhanced photocatalytic and antibacterial activity. These results unveiled the enhanced mechanism of Au on ZnO and these materials have great potential for use in water purification and antibacterial products.
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Antibacterianos/farmacología , Oro/farmacología , Nanoestructuras/química , Especies Reactivas de Oxígeno/metabolismo , Óxido de Zinc/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Catálisis , Relación Dosis-Respuesta a Droga , Escherichia coli/efectos de los fármacos , Oro/química , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Procesos Fotoquímicos , Staphylococcus aureus/efectos de los fármacos , Relación Estructura-Actividad , Propiedades de Superficie , Óxido de Zinc/síntesis química , Óxido de Zinc/químicaRESUMEN
Intact protein expression profiling has proven to be a powerful tool for bacterial subspecies differentiation. To facilitate typing, epidemiology, and trace-back of Salmonella contamination in the food supply, a minimum of serovar level differentiation is required. Subsequent identification and validation of marker proteins is integral to rapid screening development and to determining which proteins are subject to environmental pressure. Bacterial sequencing efforts have expanded the number of sequenced genomes available for single-nucleotide polymorphism (SNP) analyses, but annotation is often missing, start site errors are not uncommon, and the likelihood of expression is not known. In this work we show that the combination of intact protein expression profiles and top-down liquid chromatography-mass spectrometry (LC-MS/MS) facilitates the identification of proteins that result from expressed serovar specific nonsynonymous SNPs. Combinations of these marker proteins can be used in assays for rapid differentiation of bacteria. LC-MS generated intact protein expression profiles establish which bacterial protein masses differ across samples and can be determined without prior knowledge of the sample. Subsequent top-down LC-MS/MS is used to identify expressed proteins and their post-translational modifications (PTM), identify serovar specific markers, and validate genomic predicted orthologues as expressed biomarkers.
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Proteínas Bacterianas/análisis , Salmonella/clasificación , Espectrometría de Masas en Tándem/métodos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Cromatografía Líquida de Alta Presión , Polimorfismo de Nucleótido Simple , Procesamiento Proteico-Postraduccional , Salmonella/genética , Salmonella typhimurium/clasificación , Salmonella typhimurium/genética , SerogrupoRESUMEN
BACKGROUND: Coronary effluent from an isolated perfused heart undergoing ischemic preconditioning can be transferred to precondition another naïve isolated heart. We investigated the effects of this effluent on mitochondrial integrity and function following a global infarct model of ischemia/reperfusion and the role of adenosine in this model of remote preconditioning. METHODS AND RESULTS: Coronary effluent from isolated perfused rabbit hearts was collected prior to (control effluent) and during three cycles of 5-min ischemia and 10-min reperfusion (IPC effluent). Adenosine concentration was significantly increased in IPC effluent (2.6 ± 1.1 µM) versus control effluent (0.21 ± 0.06 µM, P < 0.01). Infarct size (% necrotic LV mass) after 30-min global ischemia and 90-min reperfusion was significantly reduced in hearts preconditioned with IPC effluent (IPC(eff), 23 ± 7 %) and control effluent supplemented with 2.5 µM exogenous adenosine (C(eff)+ 2.5 µM ADO, 25 ± 10 %) when compared to control effluent perfused hearts (C(eff), 41 ± 8 %, P < 0.05). Compared to C(eff) mitochondria, IPC(eff) mitochondria had preserved complex I/State3 and complex IV/State 3 respiration and outer membrane integrity, and reduced cytochrome c release. In contrast, C(eff) + 2.5 µM ADO mitochondria had improved state 2 respiration and coupling to oxidative phosphorylation, reduced reactive oxygen species production and preserved outer membrane integrity. Administration of adenosine receptor blocker 8-(p-sulfophenyl)theophylline abolished the infarct limiting effect (46 ± 7 %) and the mitochondrial integrity and function preservation of IPC effluent. CONCLUSION: Remote cardioprotection by IPC effluent preserves mitochondrial integrity and function in an adenosine receptor dependent mechanism, and although infarct size reduction can be mimicked by adenosine, IPC effluent contains additional factor(s) contributing to modulation of the mitochondrial response to ischemia/reperfusion injury.
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Precondicionamiento Isquémico Miocárdico/métodos , Infarto del Miocardio/prevención & control , Daño por Reperfusión Miocárdica/fisiopatología , Receptores Purinérgicos P1/metabolismo , Adenosina/metabolismo , Animales , Modelos Animales de Enfermedad , Masculino , Mitocondrias/metabolismo , Infarto del Miocardio/etiología , Infarto del Miocardio/patología , Conejos , Especies Reactivas de Oxígeno/metabolismo , Teofilina/análogos & derivados , Teofilina/farmacologíaRESUMEN
Self-assembled arrays of hemispherical gallium nanoparticles deposited by molecular beam epitaxy on a sapphire support are explored as a new type of substrate for ultraviolet plasmonics. Spin-casting a 5 nm film of crystal violet upon these nanoparticles permitted the demonstration of surface-enhanced Raman spectra, fluorescence, and degradation following excitation by a HeCd laser operating at 325 nm. Measured local Raman enhancement factors exceeding 10(7) demonstrate the potential of gallium nanoparticle arrays for plasmonically enhanced ultraviolet detection and remediation.
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With the recent emphasis on offshore wind energy Coastal and Marine Spatial Planning (CMSP) has become one of the main frameworks used to plan and manage the increasingly complex web of ocean and coastal uses. As wind development becomes more prevalent, existing users of the ocean space, such as commercial shippers, will be compelled to share their historically open-access waters with these projects. Here, we demonstrate the utility of using cost-effectiveness analysis (CEA) to support siting decisions within a CMSP framework. In this study, we assume that large-scale offshore wind development will take place in the US Mid-Atlantic within the next decades. We then evaluate whether building projects nearshore or far from shore would be more cost-effective. Building projects nearshore is assumed to require rerouting of the commercial vessel traffic traveling between the US Mid-Atlantic ports by an average of 18.5 km per trip. We focus on less than 1500 transits by large deep-draft vessels. We estimate that over 29 years of the study, commercial shippers would incur an additional $0.2 billion (in 2012$) in direct and indirect costs. Building wind projects closer to shore where vessels used to transit would generate approximately $13.4 billion (in 2012$) in savings. Considering the large cost savings, modifying areas where vessels transit needs to be included in the portfolio of policies used to support the growth of the offshore wind industry in the US.
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Energía Renovable/economía , Navíos , Océano Atlántico , Comercio , Ahorro de Costo , Análisis Costo-Beneficio , Técnicas de Apoyo para la Decisión , Estados UnidosRESUMEN
Noncontrol deals protect local governance, yet yield mergerlike benefits.
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Conducta Cooperativa , Hospitales con Fines de Lucro , Autonomía Profesional , Modelos Organizacionales , Innovación Organizacional , Patient Protection and Affordable Care Act , Estados UnidosRESUMEN
Multiple initiatives are underway to harness the clinical benefits of remote ischemic preconditioning (rIPC) based on applying non-invasive, brief, intermittent limb ischemia/reperfusion using an external occluder. However, little is known about how rIPC induces protection in cardiomyocytes, particularly through G-protein coupled receptors. In these studies, we determined the role of opioid and adenosine receptors and their functional interactions in rIPC cardioprotection. In freshly isolated cardiomyocytes subjected to 45-min simulated ischemia followed by 60-min simulated reperfusion, we examined the ability of plasma dialysate (derived from blood obtained from rabbits remotely preconditioned by application of brief cycles of hind limb ischemia/reperfusion, rIPC dialysate) to protect cells against necrosis. rIPC dialysate and selective activation of either δ-opioid receptors or κ-opioid receptors significantly reduced the % of dead cells after simulated ischemia and simulated reperfusion. Inhibition of adenosine A1 receptors, but not adenosine A3 receptors, blocked the protection by rIPC dialysate, δ-opioid receptor and κ-opioid receptor activation. In HEK293 cells expressing either hemagglutinin A-tagged δ-opioid receptors or hemagglutinin A-tagged κ-opioid receptors, selective immunoprecipitation of adenosine A1 receptors pulled down both δ-opioid and κ-opioid receptors. This molecular association of adenosine A1 receptors with δ-opioid and κ-opioid receptors was confirmed by reverse pull-down assays. These findings strongly suggest that rIPC cardioprotection requires the activation of δ-opioid and κ-opioid receptors and relies on these receptors functionally interacting with adenosine A1 receptors.
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Precondicionamiento Isquémico Miocárdico , Miocitos Cardíacos/metabolismo , Receptor de Adenosina A1/metabolismo , Receptores Opioides delta/metabolismo , Receptores Opioides kappa/metabolismo , Antagonistas del Receptor de Adenosina A1/farmacología , Animales , Células HEK293 , Humanos , Miocitos Cardíacos/patología , ConejosRESUMEN
Increasing importation of food and the diversity of potential contaminants have necessitated more analytical testing of these foods. Historically, mass spectrometric methods for testing foods were confined to monitoring selected ions (SIM or MRM), achieving sensitivity by focusing on targeted ion signals. A limiting factor in this approach is that any contaminants not included on the target list are not typically identified and retrospective data mining is limited. A potential solution is to utilize high-resolution MS to acquire accurate mass full-scan data. Based on the instrumental resolution, these data can be correlated to the actual mass of a contaminant, which would allow for identification of both target compounds and compounds that are not on a target list (nontargets). The focus of this research was to develop software algorithms to provide rapid and accurate data processing of LC/MS data to identify both targeted and nontargeted analytes. Software from a commercial vendor was developed to process LC/MS data and the results were compared to an alternate, vendor-supplied solution. The commercial software performed well and demonstrated the potential for a fully automated processing solution.
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Cromatografía Liquida/instrumentación , Minería de Datos , Espectrometría de Masas/instrumentación , Algoritmos , Programas InformáticosRESUMEN
Peanuts (Arachis hypogaea) in addition to milk, eggs, fish, crustaceans, wheat, tree nuts, and soybean are commonly referred to as the "big eight" foods that contribute to the majority of food allergies worldwide. Despite the severity of allergic reactions and growing prevalence in children and adults, there is no cure for peanut allergy, leaving avoidance as the primary mode of treatment. To improve analytical methods for peanut allergen detection, researchers must overcome obstacles involved in handling complex food matrices while attempting to decipher the chemistry that underlies allergen protein interactions. To address such challenges, we conducted a global proteome characterization of raw peanuts using a sophisticated GELFrEE-PAGE-LC-MS/MS platform consisting of gel-based protein fractionation followed by mass spectrometric identification. The in-solution mass-selective protein fractionation: (1) enhances the number of unique peptide identifications, (2) provides a visual map of protein isoforms, and (3) aids in the identification of disulfide-linked protein complexes. GELFrEE-PAGE-LC-MS/MS not only overcomes many of the challenges involved in the study of plant proteomics, but enriches the understanding of peanut protein chemistry, which is typically unattainable in a traditional bottom-up proteomic analysis. A global understanding of protein chemistry in Arachis hypogaea ultimately will aid the development of improved methods for allergen detection in food.
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Alérgenos/química , Arachis/química , Cromatografía en Gel/métodos , Proteínas de Plantas/química , Secuencia de Aminoácidos , Western Blotting , Electroforesis en Gel de Poliacrilamida , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido , Espectrometría de Masas en TándemRESUMEN
Deficiencies of lysosomal ß-D-galactosidase can result in GM1 gangliosidosis, a severe neurodegenerative disease characterized by massive neuronal storage of GM1 ganglioside in the brain. Currently there are no available therapies that can even slow the progression of this disease. Enzyme enhancement therapy utilizes small molecules that can often cross the blood brain barrier, but are also often competitive inhibitors of their target enzyme. It is a promising new approach for treating diseases, often caused by missense mutations, associated with dramatically reduced levels of functionally folded enzyme. Despite a number of positive reports based on assays performed with patient cells, skepticism persists that an inhibitor-based treatment can increase mutant enzyme activity in vivo. To date no appropriate animal model, i.e., one that recapitulates a responsive human genotype and clinical phenotype, has been reported that could be used to validate enzyme enhancement therapy. In this report, we identify a novel enzyme enhancement-agent, N-nonyl-deoxygalactonojirimycin, that enhances the mutant ß-galactosidase activity in the lysosomes of a number of patient cell lines containing a variety of missense mutations. We then demonstrate that treatment of cells from a previously described, naturally occurring feline model (that biochemically, clinically and molecularly closely mimics GM1 gangliosidosis in humans) with this molecule, results in a robust enhancement of their mutant lysosomal ß-galactosidase activity. These data indicate that the feline model could be used to validate this therapeutic approach and determine the relationship between the disease stage at which this therapy is initiated and the maximum clinical benefits obtainable.
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1-Desoxinojirimicina/análogos & derivados , Terapia de Reemplazo Enzimático , Gangliosidosis GM1/metabolismo , Proteínas Mutantes/metabolismo , beta-Galactosidasa/metabolismo , 1-Desoxinojirimicina/administración & dosificación , 1-Desoxinojirimicina/farmacología , Animales , Gatos , Línea Celular Tumoral , Modelos Animales de Enfermedad , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Gangliosidosis GM1/tratamiento farmacológico , Gangliosidosis GM1/genética , Calor , Humanos , Concentración de Iones de Hidrógeno , Proteínas Mutantes/antagonistas & inhibidores , Proteínas Mutantes/química , Mutación , Desnaturalización Proteica/efectos de los fármacos , Resultado del Tratamiento , beta-Galactosidasa/antagonistas & inhibidores , beta-Galactosidasa/químicaRESUMEN
Surface-enhanced Raman Scattering (SERS) is studied in sub-wavelength metallic gratings on a substrate using a rigorous electromagnetic approach. In the ultraviolet SERS is limited by the metallic dampening, yet enhancements as large as 10(5) are predicted. It is shown that these enhancements are directly linked to the spectral position of the plasmonic band edge of the metal/substrate surface plasmon. A simple methodology is presented for selecting the grating pitch to produce optimal enhancement for a given laser frequency.
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Modelos Teóricos , Espectrometría Raman/instrumentación , Espectrometría Raman/métodos , Resonancia por Plasmón de Superficie/instrumentación , Resonancia por Plasmón de Superficie/métodos , Rayos Ultravioleta , Óxido de Aluminio/química , Campos Electromagnéticos , Rayos Láser , Metales , Propiedades de SuperficieRESUMEN
Proteomics analysis of bovine bronchoalveolar fluid (BAF) following induction of pneumonia with Mannheimia haemolytica using nanoflow liquid chromatography coupled with tandem mass spectrometry (nanoLC-MS/MS) resulted in the identification of 88 unique proteins. Proteins detected in BAF included antimicrobial peptides (AMPs), complement factors, acute-phase proteins, protease inhibitors, and proteins involved in oxidation-reduction. Notwithstanding biological variation, differences in relative protein abundance, determined using normalized peptide counts, were detected for select proteins in BAF from genuinely infected versus sham-infected animals. To demonstrate the applicability of using normalized peptide counts to assess protein expression trends, LC-MS/MS data for the acute-phase protein haptoglobin (HPT) were compared with ELISA data, and statistical evaluation of the relationship between the data revealed a strong measure of association. Differences were detected between sham- and genuinely infected animals for haptoglobin, as well as the AMPs cathelicidin-1 and cathelicidin-4, and inter-α-trypsin inhibitor heavy chain-4, a fairly novel protein involved in the acute phase response. Though the small sample size limited the scope of the inferences, the results indicate the likely importance of AMPs and acute-phase proteins during respiratory infection, and provide additional information regarding potential mechanisms involved in the bovine mucosal barrier defense.
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Líquido del Lavado Bronquioalveolar/química , Bovinos/metabolismo , Mannheimia haemolytica/patogenicidad , Proteoma/análisis , Animales , Líquido del Lavado Bronquioalveolar/inmunología , Líquido del Lavado Bronquioalveolar/microbiología , Catelicidinas/análisis , Bovinos/microbiología , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/microbiología , Cromatografía Liquida , Ensayo de Inmunoadsorción Enzimática , Haptoglobinas/análisis , Masculino , Mannheimia haemolytica/inmunología , Fragmentos de Péptidos/análisis , Neumonía Enzoótica de los Becerros/inmunología , Neumonía Enzoótica de los Becerros/microbiología , Proteómica , Espectrometría de Masas en TándemRESUMEN
Difficulty in managing the airway is a major contributor to the morbidity and mortality of the trauma patient. The video laryngoscope, with its camera at the distal tip of the intubation blade, allows the practitioner an improved view of the glottic opening during intubation. The image from this viewer is transmitted to a monitor, allowing the intubating practitioner to "see around the corner" of a patient's airway. The purpose of the present study was to assess and compare the video quality of commercially available video laryngoscopy systems. It was found that between the STORZ C-MAC and the Verathon GlideScope® there was little difference between the video quality; the difference came down to user preference.
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Intubación Intratraqueal/instrumentación , Laringoscopios , Grabación en Video/instrumentación , Biotecnología/instrumentación , Diseño de Equipo , Análisis de Falla de EquipoRESUMEN
Though dedicated videoteleconference (VTC) systems deliver high quality, low-latency audio and video for telemedical applications, they require expensive hardware and extensive infrastructure. The purpose of this study was to investigate free commercially available Voice over Internet Protocol (VoIP) software as a low cost alternative for telemedicine.
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Internet , Intubación Intratraqueal/métodos , Telecomunicaciones , Telemedicina/métodos , Terapia Asistida por Computador/métodos , Interfaz Usuario-Computador , Grabación en Video/métodos , Simulación por Computador , Instrucción por Computador/métodos , Humanos , Modelos BiológicosRESUMEN
Elective surgery waiting list management is a major public healthcare issue. This case study describes an integrated multifaceted approach to waiting list management at Peninsula Health, a public health service in Victoria, Australia. At the commencement of this study it was recognised that several issues associated with the urological surgical service constituted potential clinical risk. These included: recall mechanisms for multiple surveillance procedures; significant resource deficits; and long surgery waiting times. Responding to these issues a multifaceted approach to wait list management was implemented including: audit; direct lines of communication between clinical and administrative staff; urgent caseload management; utilisation of the Elective Surgery Access Scheme; financial and resource analysis justifying the appointment of a full-time urologist, and the establishment of a urology service from a satellite campus; implementation of a recall database; development of an outpatient service; and commencement of a day surgery initiative. This approach yielded results that included a 67% reduction in the number of 'ready for care' patients and a 78% reduction in the number of patients classified as 'overdue for surgery'. Average wait time for semi-urgent and non-urgent patients reduced from 248 days to 180 days in the 10-month period.
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Eficiencia Organizacional , Procedimientos Quirúrgicos Electivos , Procedimientos Quirúrgicos Urológicos , Listas de Espera , Humanos , Estudios de Casos Organizacionales , VictoriaRESUMEN
In this study we investigated the differentiation of human neural progenitor cells (hNPCs) in vitro to evaluate their differentiation potential and in vivo to explore their viability and behavior following transplantation. Progenitors were maintained as neurospheres in media containing basic fibroblast growth factor and epidermal growth factor. Micropatterned polystyrene substrates were fabricated and coated with ECL (entactin, collagen, and laminin) to provide physical and chemical guidance during the differentiation of the hNPCs. The hNPCs growing on the micropatterned substrates showed no differences in proliferation or differentiation potential compared with those hNPCs growing on the nonpatterned substrates. However, hNPCs cultured on the micropatterned substrates were aligned in the direction of the micropattern compared with those cells growing on the nonpatterned substrates. Furthermore, hNPC migration was directed in alignment with the micropatterned substrates. Transplantation of the hNPCs into the developing retina was used to evaluate their behavior in vivo. Cells displayed extensive survival, differentiation, and morphological integration following xenotransplant into the retina, even in the absence of immunosuppression. Taken together, our results show that these multipotent hNPCs are a neurogenic progenitor population that can be maintained in culture for extended periods. Although the micropatterned substrates have no major effect on the proliferation or differentiation of the hNPCs, they clearly promoted alignment and directed neurite outgrowth along the pattern as well as directing migration of the cells. These approaches may provide important strategies to guide the growth and differentiation of NPCs in vitro and in vivo.
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Diferenciación Celular/fisiología , Medios de Cultivo/farmacología , Supervivencia de Injerto/fisiología , Retina/crecimiento & desarrollo , Trasplante de Células Madre/métodos , Células Madre/fisiología , Técnicas de Cultivo de Célula , Movimiento Celular/fisiología , Proliferación Celular , Células Cultivadas , Colágeno/química , Colágeno/farmacología , Medios de Cultivo/química , Humanos , Laminina/química , Laminina/farmacología , Neurogénesis/fisiología , Neuronas/citología , Neuronas/fisiología , Poliestirenos/química , Poliestirenos/farmacología , Retina/citología , Retina/cirugía , Esferoides Celulares/citología , Esferoides Celulares/fisiología , Células Madre/citologíaRESUMEN
Chediak-Higashi syndrome is characterized by oculocutaneous albinism, a bleeding tendency and severe recurrent infections. Age-dependent formations of autofluorescent ceroid-like substances have been noted in a variety of tissues. In this study, we isolated an autofluorescent ceroid-like aggregate from purified Beige mouse liver lysosomes and analyzed the composition of the aggregate by ion trap mass-spectrometry. In addition to lysosomal proteins, this aggregate contains proteins normally localized in the ER, mitochondria, peroxisomes, and the cytosol. Bip, a luminal ER protein was abundant in lysosomal ceroid. The ER, mitochondria, and cytosol proteins could arise in lysosomes through stimulation of autophagy, but we found no differences between normal and CHS fibroblasts in the degree of lysosomal acidity and in the level of conversion of soluble microtubular-associated protein 1 light chain 3 type I to membrane-associated type II, an accepted probe for hyper-autophagy suggesting that ceroid formation is unlikely to arise via this mechanism.
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Ceroide/metabolismo , Síndrome de Chediak-Higashi/metabolismo , Hígado/metabolismo , Lisosomas/metabolismo , Animales , Autofagia , Células Cultivadas , Modelos Animales de Enfermedad , Fluorescencia , Espectrometría de Masas , Ratones , Proteínas/metabolismo , ProteómicaRESUMEN
A transmissive, square-wave Ronchi phase grating has been fabricated from the dielectric polytetrafluoroethylene to diffract an ~0.7 THz beam quasi-optically. When illuminated by a coherent, cw terahertz (THz) source, the spot separation of the ±1 diffractive orders and the diffraction efficiency were measured as a function of THz frequency and rotation angle. The grating performance depends sensitively on the refractive index, whose value can be measured with an accuracy limited by the fabrication precision. The use of these gratings for polarization-insensitive quasi-optical imaging and phased arrays is discussed.