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Surface Modification of Erythrocytes with Lipid Anchors: Structure-Activity Relationship for Optimal Membrane Incorporation, in vivo Retention, and Immunocompatibility. ADVANCED NANOBIOMED RESEARCH 2022; 2:2200037. [PMID: 36591390 PMCID: PMC9797212 DOI: 10.1002/anbr.202200037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Red blood cells (RBCs) are natural carriers for sustained drug delivery, imaging, and in vivo sensing. One of the popular approaches to functionalize RBCs is through lipophilic anchors, but the structural requirements for anchor stability and in vivo longevity remain to be investigated. Using fluorescent lipids with the same cyanine 3 (Cy3) headgroup but different lipid chain and linker, the labeling efficiency of RBCs and in vivo stability are investigated. Short-chain derivatives exhibited better insertion efficiency, and mouse RBCs are better labeled than human RBCs. Short-chain derivatives demonstrate low retention in vivo. Derivatives with ester bonds are especially unstable, due to removal and degradation. On the other hand, long-chain, covalently linked derivatives show remarkably long retention and stability (over 80 days half life in the membrane). The clearance organs are liver and spleen with evidence of lipid transfer to the liver sinusoidal endothelium. Notably, RBCs modified with PEGylated lipid show decreased macrophage uptake. Some of the derivatives promote binding of antibodies in human plasma and mouse sera and modest increase in complement deposition and hemolysis, but these do not correlate with in vivo stability of RBCs. Ultra-stable anchors can enable functionalization of RBCs for drug delivery, imaging, and sensing.
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Surface Modification of Erythrocytes with Lipid Anchors: Structure–Activity Relationship for Optimal Membrane Incorporation, in vivo Retention, and Immunocompatibility. ADVANCED NANOBIOMED RESEARCH 2022. [DOI: 10.1002/anbr.202270081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Management and Associated Toxicokinetics of Massive Valproic Acid Ingestion with High Flow Continuous Venovenous Hemodiafiltration. J Med Toxicol 2022; 18:239-242. [PMID: 35235162 DOI: 10.1007/s13181-022-00881-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 11/28/2022] Open
Abstract
INTRODUCTION Valproic acid (VPA) toxicity commonly results in a self-limited state of CNS depression that is managed with supportive care and levocarnitine. In massive overdose, patients can develop toxic encephalopathy, shock, multisystem organ failure, and death. We present a case with relevant toxicokinetics of a patient presenting with a profoundly elevated VPA concentration resulting in survival, treated with supportive care including high-dose continuous venovenous hemodiafiltration (CVVHDF). CASE REPORT A 17-year-old female presented to an emergency department after being found unresponsive at home with concern for massive VPA ingestion. She arrived obtunded and hypotensive with initial VPA concentration of 2226 mg/L, estimated 9 h post-ingestion. Her early hospital course was marked by hypotension requiring multiple vasopressors, and her workup was notable for multiple severe metabolic derangements. High-dose CVVHDF was initiated upon transfer to a tertiary children's hospital with the aim to enhance VPA removal and normalize metabolic derangements. At that time, her VPA concentration was 1071 mg/L. Apparent half-life of VPA improved modestly with extracorporeal treatment, but her metabolic derangements and hemodynamic instability corrected rapidly. Her clinical course was complicated by necrotizing pancreatitis, pancytopenia requiring transfusions of multiple cell lines, coma, and seizures. She ultimately recovered with normal neurological function.
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P-P14 A multi-centre retrospective cohort study exploring weight loss and nutritional interventions in severe acute pancreatitis. Br J Surg 2021. [DOI: 10.1093/bjs/znab430.237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Background
Acute pancreatitis is among the most common acute gastrointestinal diseases. Severe acute pancreatitis (SAP) develops in up to 20% of patients and is associated with increased morbidity and mortality. Patients may have long and complex hospital admissions; nutritional support is a cornerstone of management. Due to increased metabolic demands and development of pancreatic exocrine insufficiency (PEI) patients frequently endure excessive weight loss. There has been little research into the effect of SAP on nutritional status and necessary nutritional interventions. This project aimed to characterise weight loss in SAP, routes of feeding, and PEI - including pancreatic enzyme replacement therapy (PERT).
Methods
Participating centres were recruited via the Nutrition Interest group of PSGBI and were required to retrospectively recruit 5-10 consecutive patients admitted following January 1st 2018 using a predefined data collection tool. Inclusion criteria included; age ≥18 years and diagnosed SAP of any aetiology (defined by organ failure of > 48hrs). The exclusion criterion was where death occurred during hospital admission. Data were collected regarding, weight changes, anthropometric measures, nutritional interventions used, PERT administration and diabetic status, including insulin use. All analyses were performed with IBM SPSS 22 (IBM Corp. Armonk, NY), with p < 0.05 considered statistically significant.
Results
34 patients (22 male) from five centres met the inclusion criteria and were included in data analysis. Most common aetiologies were gallstones (13/34) and alcohol (11/34). A mean weight reduction of 12.6% (SD ± 10.77) (p < 0.001) was observed. Multivariate analyses showed that higher premorbid weight (p = 0.02) and PERT administration with tube feeding (p = 0.005) were associated with weight loss. Most patients (29/34) received tube feeding; mean duration 56.8 (SD ± 58.29) days. There was a significant increase in patients with diabetes requiring insulin therapy from admission (n = 3) to discharge (n = 9) (p = 0.03). Most (29/31) patients required oral PERT prescription on discharge.
Conclusions
Patients with SAP lost significant weight during the course of their illness despite aggressive, extended nutritional support and the correction of PEI with PERT. The significant increase in insulin dependence among patients with diabetes, and the number of patients requiring PERT on discharge, reflects the destructive effect SAP has on pancreatic function. These multicentre findings could be used as a baseline for determining effectiveness of nutritional interventions in SAP and may provide a basis for further prospective research in this area.
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Novel multidisciplinary hub-and-spoke tertiary service for the management of severe acute pancreatitis. BMJ Open Gastroenterol 2021; 8:bmjgast-2020-000501. [PMID: 33789915 PMCID: PMC8016076 DOI: 10.1136/bmjgast-2020-000501] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 11/26/2020] [Accepted: 02/28/2021] [Indexed: 01/04/2023] Open
Abstract
OBJECTIVE Severe acute pancreatitis (SAP) is associated with high mortality (15%-30%). Current guidelines recommend these patients are best managed in a multidisciplinary team setting. This study reports experience in the management of SAP within the UK's first reported hub-and-spoke pancreatitis network. DESIGN All patients with SAP referred to the remote care pancreatitis network between 2015 and 2017 were prospectively entered onto a database by a dedicated pancreatitis specialist nurse. Baseline characteristics, aetiology, intensive care unit (ICU) stay, interventions, complications, mortality and follow-up were analysed. RESULTS 285 patients admitted with SAP to secondary care hospitals during the study period were discussed with the dedicated pancreatitis specialist nurse and referred to the regional service. 83/285 patients (29%; 37 male) were transferred to the specialist centre mainly for drainage of infected pancreatic fluid collections (PFC) in 95% (n=79) of patients. Among the patients transferred; 29 (35%) patients developed multiorgan failure with an inpatient mortality of 14% (n=12/83). The median follow-up was 18.2 months (IQR=11.25-35.51). Multivariate analysis showed that transferred patients had statistically significant longer overall hospital stay (p<0.001) but less ICU stay (p<0.012). CONCLUSION This hub-and-spoke model facilitates the management of the majority of patients with SAP in secondary care setting. 29% warranted transfer to our tertiary centre, predominantly for endoscopic drainage of PFCs. An evidence-based approach with a low threshold for transfer to tertiary care centre can result in lower mortality for SAP and fewer days in ICU.
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A Novel Strategy for Automatic Error Classification and Error Recovery for Robotic Assembly in Flexible Production. J INTELL ROBOT SYST 2020. [DOI: 10.1007/s10846-020-01248-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AbstractIn this article, we develop a novel strategy for automatic error classification and recovery in robotic assembly tasks. The strategy does not require error diagnosis. It allows for effective reduction of an undetermined number of error states to 4, without the need for further operator updates of error space. The strategy integrates existing methods for computer vision, active vision and active manipulation. Our solution is implemented in a generic software framework, which is independent from software and hardware for implementing error detection and allows for application in other assembly types and components. The value of our strategy was experimentally validated on a simple case, where we inserted a battery into a cell phone. The experiment was performed on 1500 assembly attempts and included 500 detected errors. The whole experiment ran for 42 hours, with no need for operator assistance or supervision. The resulting classification rate is 99.6% and the resulting recovery rate is 98.8%. The 6 unrecovered errors were successfully resolved in a successive assembly attempt.
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Effect of Particle Size and Viscosity of Suspensions on Topical Ocular Bioavailability of Budesonide, a Corticosteroid. J Ocul Pharmacol Ther 2020; 36:404-409. [PMID: 32678687 DOI: 10.1089/jop.2019.0150] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Purpose: To determine the effect of particle size and viscosity of suspensions on topical ocular bioavailability of budesonide, a corticosteroid drug. Methods: Budesonide microparticle and nanoparticle (MP and NP) suspensions were prepared with or without homogenization and microfluidization. Using different grades of hydroxyl propyl methyl cellulose, low viscosity NP (NP-LV) and low and high viscosity MP (MP-LV and MP-HV) were prepared. Suspensions were characterized for particle size, viscosity, and osmolality. Budesonide suspensions were administered topically to rabbits and aqueous humor was collected and analyzed for budesonide. Budesonide Cmax, tmax, and the area under the concentration time curve (AUC (0-6h)) values were determined. The geometric mean ratio of AUC and bioequivalence was evaluated using a bootstrap method. Results: The particle sizes for NP and MP were ∼700 and 2,000 nm. The viscosities for low and HV formulations were ∼5 and 50 cP. The geometric mean budesonide Cmax values for the suspensions NP-LV, MP-LV, and MP-HV were 0.22, 0.22, and 0.31 μg/g, tmax values were 0.67, 0.60 and 0.53 h, and AUC0-6h values were 0.72, 0.53, and 0.95 μg h/g, respectively. Bootstrap analysis indicated that the 90% confidence intervals of the geometric mean ratio of AUC0-6h values were 1.00-1.74 (MP-HV vs. NP-LV), 0.57-0.96 (MP-LV vs. NP-LV), and 0.45-0.70 (MP-LV vs. MP-HV). Conclusions: The 3 budesonide suspensions assessed in this study were not bioequivalent. Results suggested that an increase in viscosity improves the bioavailability of budesonide from the microsuspension formulation.
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Can we meet patients’ energy and nitrogen requirements with standard peripheral parenteral nutrition bags? Clin Nutr ESPEN 2020. [DOI: 10.1016/j.clnesp.2019.12.069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Dexamethasone Degradation in Aqueous Medium and Implications for Correction of In Vitro Release from Sustained Release Delivery Systems. AAPS PharmSciTech 2019; 20:320. [PMID: 31646399 DOI: 10.1208/s12249-019-1508-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 08/08/2019] [Indexed: 11/30/2022] Open
Abstract
The in vitro drug release in an aqueous medium is a critical performance metric for a sustained release drug product. During long-term release studies, drugs may degrade in the release medium, and such degradation can lead to errors in drug release quantitation. Using dexamethasone as a model drug and LC-MS/MS methods employing dexamethasone-d4 as an internal standard, this study identified that dexamethasone can degrade into 13 major degradation products in phosphate buffered saline (PBS) as a function of time, temperature (25, 37, and 45°C), and light exposure. A putative scheme for dexamethasone degradation pathways in PBS has been proposed. In proof-of-concept studies, the analytical method was used to quantitate dexamethasone and its degradation products during in vitro release studies with sustained release dexamethasone-poly(D,L-lactide-co-glycolide) (PLGA) implants incubated in phosphate buffer saline (PBS). Further, mathematical approaches were developed to estimate drug release from implants after accounting for drug degradation in PBS. The LC-MS/MS analytical method and the mathematical approaches developed could be used for assessing the stability and/or release of dexamethasone during manufacturing, storage, and use of various dosage forms.
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Pharmacokinetic analysis reveals limitations and opportunities for nanomedicine targeting of endothelial and extravascular compartments of tumours. J Drug Target 2019; 27:690-698. [PMID: 30614276 DOI: 10.1080/1061186x.2019.1566339] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Targeting of nanoparticles to tumours can potentially improve the specificity of imaging and treatments. We have developed a multicompartmental pharmacokinetic model in order to analyse some of the factors that control efficiency of targeting to intravascular (endothelium) and extravascular (tumour cells and stroma) compartments. We make the assumption that transport across tumour endothelium is an important step for subsequent nanoparticle accumulation in the tumour (area-under-the-curve, AUC) regardless of entry route (interendothelial and transendothelial routes) and study this through a multicompartmental simulation. Our model reveals that increasing endothelial targeting efficiency has a much stronger effect on the AUC than increasing extravascular targeting efficiency. Furthermore, our analysis reveals that both extravasation and intratumoral diffusion rates need to be increased in order to significantly increase the AUC of extravascular-targeted nanoparticles. Increasing the nanoparticle circulation half-life increases the AUC independently of extravasation and intratumoral diffusion. Targeting the extravascular compartment leads to a buildup in the first layer surrounding blood vessels at the expense of deeper layers (binding site barrier). This model explains some of the limitations of tumour targeting and provides important guidelines for the design of targeted nanomedicines.
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Abstract
Addressable self-assembly is the formation of a target structure from a set of unique molecular or colloidal building blocks, each of which occupies a defined location in the target. The requirement that each type of building block appears exactly once in each copy of the target introduces severe restrictions on the combinations of particles and on the pathways that lead to successful self-assembly. These restrictions can limit the efficiency of self-assembly and the final yield of the product. In particular, partially formed fragments may compete with each other if their compositions overlap, since they cannot be combined. Here, we introduce a "completability" algorithm to quantify competition between self-assembling fragments and use it to deduce general principles for suppressing the effects of fragment incompatibility in the self-assembly of small addressable clusters. Competition originates from loops in the bonding network of the target structure, but loops may be needed to provide structural rigidity and thermodynamic stability. An optimal compromise can be achieved by careful choice of bonding networks and by promoting semihierarchical pathways that rule out competition between early fragments. These concepts are illustrated in simulations of self-assembly in two contrasting addressable targets of 20 unique components each.
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Rituximab Exhibits Altered Pharmacokinetics in Patients With Membranous Nephropathy. Ann Pharmacother 2018; 53:357-363. [PMID: 30293439 DOI: 10.1177/1060028018803587] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Rituximab (RTX) is a chimeric monoclonal anti-CD20 antibody used off-label in the treatment of membranous nephropathy (MN). Unfortunately, limited information is available on the pharmacokinetics of therapeutic proteins such as RTX in patients with glomerular kidney diseases. OBJECTIVE The current study evaluated RTX pharmacokinetics in patients with MN (n = 20) who received 4 RTX weekly intravenous infusions (375 mg/m2) over a month, with a repeat of the identical treatment at 6 months. Baseline patient characteristics were gender (17 male/3 female), age (49 ± 13 years), and body surface area (2.2 ± 0.24 m2). METHODS Compartmental pharmacokinetic analyses were conducted using Phoenix, and comparisons of these parameters were made between the MN patients and published data from 2 reference populations without kidney diseases (follicular lymphoma and autoimmune disorders). RESULTS Patients with MN exhibited a shorter half-life, reduced volume of central compartment, decreased area under the serum concentration-time curve (exposure), and increased RTX clearance from the central compartment versus previous reports in the reference patient populations. CONCLUSIONS AND RELEVANCE These results suggest that shorter half-life and lower exposures to RTX in patients with MN may necessitate higher doses and/or changes to dosing frequency to optimize the relationships between serum concentrations and therapeutic effects.
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Evaluating Clinical Effectiveness and Pharmacokinetic Profile of Atomized Intranasal Midazolam in Children Undergoing Laceration Repair. J Emerg Med 2017; 53:397-404. [PMID: 28992870 DOI: 10.1016/j.jemermed.2017.05.029] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 05/08/2017] [Accepted: 05/30/2017] [Indexed: 11/20/2022]
Abstract
BACKGROUND Atomized intranasal midazolam is a common adjunct in pediatrics for procedural anxiolysis. There are no previous studies of validated anxiety scores with pharmacokinetic data to support optimal procedure timing. OBJECTIVES We describe the clinical and pharmacokinetic profile of atomized intranasal midazolam in children presenting for laceration repair. METHODS Children 11 months to 7 years of age and weighing <26 kg received 0.4 mg/kg of atomized intranasal midazolam for simple laceration repair. Blood samples were obtained at 3 time points in each patient, and the data were fit with a 1-compartment model. Patient anxiety was rated with the Observational Scale of Behavioral Distress. Secondary outcomes included use of adjunctive medications, successful completion of procedure, and adverse events. RESULTS Sixty-two subjects were enrolled, with a mean age of 3.3 years. The median time to peak midazolam concentration was 10.1 min (interquartile range 9.7-10.8 min), and the median time to the procedure was 26 min (interquartile range 21-34 min). There was a trend in higher Observational Scale of Behavioral Distress scores during the procedure. We observed a total of 2 adverse events, 1 episode of vomiting (1.6%) and 1 paradoxical reaction (1.6%). Procedural completion was successful in 97% of patients. CONCLUSIONS Atomized intranasal midazolam is a safe and effective anxiolytic to facilitate laceration repair. The plasma concentration was >90% of the maximum from 5 to 17 min, suggesting this as an ideal procedural timeframe after intranasal midazolam administration.
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The design and physical characterization of a multileaf collimator for robotic radiosurgery. Biomed Phys Eng Express 2016. [DOI: 10.1088/2057-1976/2/1/017003] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Appropriate prescribing of oral nutritional supplementation (ONS) in the post-operative period: A complete audit cycle in a tertiary referral centre. Int J Surg 2015. [DOI: 10.1016/j.ijsu.2015.07.278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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15 * SYNCOPE-CAN THE USE OF A RISK-STRATIFICATION SCORE REDUCE ADMISSIONS AND IMPROVE CARE QUALITY? Age Ageing 2015. [DOI: 10.1093/ageing/afv029.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Effect of Cytochrome P450 2C8*3 on the Population Pharmacokinetics of Pioglitazone in Healthy Caucasian Volunteers. Biol Pharm Bull 2013; 36:245-51. [PMID: 23370354 DOI: 10.1248/bpb.b12-00657] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Pioglitazone, a peroxisome proliferator-activated receptor-γ agonist, is indicated for the treatment of type 2 diabetes. Pioglitazone undergoes hepatic metabolism by cytochrome P450 2C8 (CYP2C8) and interindividual variability exists in pioglitazone disposition and response. In previous analyses, it has been shown that the CYP2C8*3 polymorphism significantly impacts pioglitazone pharmacokinetics in humans. The purpose of this investigation was to develop a population pharmacokinetic model using nonlinear mixed effects analysis to evaluate and quantify the effect of CYP2C8*3, demographic, and clinical variables on interindividual variability in pioglitazone pharmacokinetics in nondiabetic adults. Data were obtained from 31 healthy volunteers (n=16 CYP2C8*1/*1, n=15 CYP2C8*3 carriers) who had previously participated in the monotherapy phase of a pioglitazone drug-drug interaction study. Participants received a single 15 g dose of pioglitazone followed by a 48-h sampling period. A two-compartment model with first order absorption and elimination (Akaike Information Criteria (AIC)=2889) showed a better fit for pioglitazone than a one-compartment model (AIC=3008). Covariate analysis revealed that CYP2C8*3 had a significant effect on pioglitazone central compartment clearance (CL/F; p=0.0005) and intercompartmental clearance (Q/F; p=0.004). Pioglitazone CL/F and Q/F were 52% and 286% higher, respectively, in carriers of the CYP2C8*3 allele than in CYP2C8*1 homozygotes. Furthermore, inclusion of CYP2C8*3 as a covariate on CL/F and Q/F decreased interindividual variability in these parameters by 5.2% and 14%, respectively. Other variables (e.g., sex, body weight) were not significant covariates on pioglitazone pharmacokinetics in the model. In summary, CYP2C8*3 significantly affected pioglitazone CL/F, Q/F, and interindividual variability in these parameters in this healthy volunteer cohort.
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Transcriptional activation of c3 and hsp70 as part of the immune response of Acropora millepora to bacterial challenges. PLoS One 2013; 8:e67246. [PMID: 23861754 PMCID: PMC3701546 DOI: 10.1371/journal.pone.0067246] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2013] [Accepted: 05/14/2013] [Indexed: 12/16/2022] Open
Abstract
The impact of disease outbreaks on coral physiology represents an increasing concern for the fitness and resilience of reef ecosystems. Predicting the tolerance of corals to disease relies on an understanding of the coral immune response to pathogenic interactions. This study explored the transcriptional response of two putative immune genes (c3 and c-type lectin) and one stress response gene (hsp70) in the reef building coral, Acropora millepora challenged for 48 hours with bacterial strains, Vibrio coralliilyticus and Alteromonas sp. at concentrations of 10(6) cells ml(-1). Coral fragments challenged with V. coralliilyticus appeared healthy while fragments challenged with Alteromonas sp. showed signs of tissue lesions after 48 hr. Coral-associated bacterial community profiles assessed using denaturing gradient gel electrophoresis changed after challenge by both bacterial strains with the Alteromonas sp. treatment demonstrating the greatest community shift. Transcriptional profiles of c3 and hsp70 increased at 24 hours and correlated with disease signs in the Alteromonas sp. treatment. The expression of hsp70 also showed a significant increase in V. coralliilyticus inoculated corals at 24 h suggesting that even in the absence of disease signs, the microbial inoculum activated a stress response in the coral. C-type lectin did not show a response to any of the bacterial treatments. Increase in gene expression of c3 and hsp70 in corals showing signs of disease indicates their potential involvement in immune and stress response to microbial challenges.
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Liposome-encapsulated EF24-HPβCD inclusion complex: a preformulation study and biodistribution in a rat model. JOURNAL OF NANOPARTICLE RESEARCH : AN INTERDISCIPLINARY FORUM FOR NANOSCALE SCIENCE AND TECHNOLOGY 2011; 13:2609-2623. [PMID: 21779150 PMCID: PMC3138191 DOI: 10.1007/s11051-010-0154-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
3,5-Bis(2-fluorobenzylidene)-4-piperidone (EF24) is an anti-proliferative diphenyldifluoroketone analog of curcumin with more potent activity. The authors describe a liposome preparation of EF24 using a "drug-in-CD-in liposome" approach. An aqueous solution of EF24 and hydroxypropyl-β-cyclodextrin (HPβCD) inclusion complex (IC) was used to prepare EF24 liposomes. The liposome size was reduced by a combination of multiple freeze-thaw cycles. Co-encapsulation of glutathione inside the liposomes conferred them with the capability of labeling with imageable radionuclide Tc-99m. Phase solubility analysis of EF24-HPβCD mixture provided k(1:1) value of 9.9 M(-1). The enhanced aqueous solubility of EF24 (from 1.64 to 13.8 mg/mL) due to the presence of HPβCD helped in the liposome preparation. About 19% of the EF24 IC was encapsulated inside the liposomes (320.5 ± 2.6 nm) by dehydration-rehydration technique. With extrusion technique, the size of 177 ± 6.5 nm was obtained without any effect on encapsulation efficiency. The EF24-liposomes were evaluated for anti-proliferative activity in lung adenocarcinoma H441 and prostate cancer PC-3 cells. The EF24-liposomes demonstrated anti-proliferative activity superior to that of plain EF24 at 10 μM dose. When injected in rats, the Tc-99m-labeled EF24-liposomes cleared from blood with an α-t(1/2) of 21.4 min and β-t(1/2) of 397 min. Tissue radioactivity counting upon necropsy showed that the majority of clearance was due to the uptake in liver and spleen. The results suggest that using "drug-in-CD-in liposome" approach is a feasible strategy to formulate an effective parenteral preparation of EF24. In vitro studies show that the liposomal EF24 remains anti-proliferative, while presenting an opportunity to image its biodistribution.
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The Provincial Injury Mortality Surveillance System (PIMSS): a surveillance tool for the Western Cape. Inj Prev 2011. [DOI: 10.1136/ip.2010.029215.172] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Incorporation, Release, and Effectiveness of Dexamethasone in Poly(Lactic-Co-Glycolic Acid) Nanoparticles for Inner Ear Drug Delivery. J Nanotechnol Eng Med 2011. [DOI: 10.1115/1.4002928] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Poly (D,L-lactide-co-glycolide) (PLGA) particles have been widely used as drug delivery carriers for a variety of payloads. Three forms of dexamethasone (DEX), namely, acetate, base, and phosphate, were incorporated into a PLGA matrix. First, we compared the drug loading efficiency and release kinetics of drug-loaded PLGA particles. Dexamethasone acetate (DEX-Ac) loaded particles exhibited a higher loading efficiency and a more linear release profile of drug as compared with the other forms of DEX particles. Also, we coincorporated oleic acid-coated superparamagnetic iron oxide nanoparticles (SPION) with DEX-Ac into PLGA submicron particles. No differences in size, zeta potential, drug loading, or release kinetics were found between particles prepared with and without SPION. Additionally, particles were applied to an in vitro cochlear, organotypic culture. DEX-Ac PLGA nanoparticles showed a protective effect against 4-hydroxynonenal induced hair cell damage. These results suggest a promising method for inner ear magnetic targeted treatment.
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A new methodology to preserve the original proportion and integrity of cell-free fetal DNA in maternal plasma during sample processing and storage. Prenat Diagn 2010; 30:418-24. [PMID: 20306459 DOI: 10.1002/pd.2484] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVE To develop a standardized blood collection device that preserves fetal cell-free DNA and minimizes the cell-free DNA background in maternal plasma. METHODS Blood samples were drawn from healthy pregnant donors into K(3)EDTA (BD vacutainer) and Cell-free DNA BCT tubes (Streck, Inc.) and kept at ambient temperature. Plasma was separated by centrifugation and cell-free DNA was extracted. Cell-free DNA from plasma was quantified by quantitative real-time polymerase chain reaction. RESULTS Blood drawn into Cell-free DNA BCT tubes showed no change in the original proportion of fetal cell-free DNA during a 14-day storage period at ambient temperature. Conversely, maternal blood drawn into K(3)EDTA tubes showed a steady reduction in the original proportion of fetal cell-free DNA over the same time period. Using maternal plasma stored in Cell-free DNA BCT tubes for 14 days, fetal cell-free DNA was amplified 80-fold using whole genome amplification (WGA). CONCLUSION Using Streck's Cell-free DNA BCT tubes, it is possible to preserve the original proportion of fetal cell-free DNA for extended times as well as minimize the post-sampling maternal cell-free DNA background. Preserved in this way, fetal cell-free DNA can be amplified by WGA technology to be used in prenatal diagnostic tests.
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Local-level mortality surveillance in resource-limited settings: a case study of Cape Town highlights disparities in health. Bull World Health Organ 2010; 88:444-51. [PMID: 20539858 PMCID: PMC2878147 DOI: 10.2471/blt.09.069435] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2009] [Revised: 10/27/2009] [Accepted: 11/02/2009] [Indexed: 10/20/2022] Open
Abstract
OBJECTIVE To identify the leading causes of mortality and premature mortality in Cape Town, South Africa, and its subdistricts, and to compare levels of mortality between subdistricts. METHODS Cape Town mortality data for the period 2001-2006 were analysed by age, cause of death and sex. Cause-of-death codes were aggregated into three main cause groups: (i) pre-transitional causes (e.g. communicable diseases, maternal causes, perinatal conditions and nutritional deficiencies), (ii) noncommunicable diseases and (iii) injuries. Premature mortality was calculated in years of life lost (YLLs). Population estimates for the Cape Town Metro district were used to calculate age-specific rates per 100,000 population, which were then age-standardized and compared across subdistricts. FINDINGS The pattern of mortality in Cape Town reflects the quadruple burden of disease observed in the national cause-of-death profile, with HIV/AIDS, other infectious diseases, injuries and noncommunicable diseases all accounting for a significant proportion of deaths. HIV/AIDS has replaced homicide as the leading cause of death. HIV/AIDS, homicide, tuberculosis and road traffic injuries accounted for 44% of all premature mortality. Khayelitsha, the poorest subdistrict, had the highest levels of mortality for all main cause groups. CONCLUSION Local mortality surveillance highlights the differential needs of the population of Cape Town and provides a wealth of data to inform planning and implementation of targeted interventions. Multisectoral interventions will be required to reduce the burden of disease.
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Treatment for tobacco dependence for rural, lower-income smokers: outcomes, predictors, and measurement considerations. Am J Health Promot 2009; 23:328-38. [PMID: 19445436 DOI: 10.4278/ajhp.06031933] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PURPOSE Outcomes from a statewide program that delivered evidence-based, intensive treatment for tobacco dependence to a rural population of lower socioeconomic status (SES) were evaluated. Factors that predicted success and measurement considerations were examined. DESIGN AND ANALYSES: Data were collected at intake, at all treatment sessions, and at 3- and 12-months posttreatment. Abstinence rates were calculated using complete-case analysis and intention-to-treat analysis, and they were estimated for all participants. Logistic regression was used to evaluate the predictive significance of demographic and clinical factors. SETTING Twenty health care sites across Arkansas. PARTICIPANTS A total of 2,350 predominantly rural, lower SES, Arkansas residents. INTERVENTION Evidence-based, six-session, multi-component cognitive-behavioral therapy with relapse prevention. RESULTS The estimated percent abstinent was 26.47% at 3-months and 21.73% at 12-months posttreatment; 51.02% of patients completed treatment and demonstrated markedly higher quit rates. Although numerous factors predicted outcomes at different points, self-efficacy and dependence levels at intake were robust predictors across time and methods of calculating outcomes. Sex, partner smoking status, and educational level were significant predictors of long-term abstinence. CONCLUSIONS This study demonstrates that intensive, evidence-based treatment for tobacco dependence can be successfully delivered in a statewide program and can yield long-term outcomes that approximate those seen in more controlled settings. Overall sample estimates may be more appropriate for the assessment of outcomes in this context.
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Accuracy of digitization of bony landmarks for measuring change in scapular attitude. Proc Inst Mech Eng H 2009; 223:349-61. [DOI: 10.1243/09544119jeim480] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Digitizing bony landmarks is a common technique used to measure scapular position, but it has not been validated against a gold standard. The aim of this study was to determine the accuracy of this technique for four physiological arm movements using optoelectronic markers mounted on scapular bone pins as a gold standard. Eight subjects had bone pins inserted into their lateral scapular spine. Three points were digitized on the scapula with an optoelectronic probe: the medial root of the scapular spine, the posterolateral corner of the acromion, and the inferior angle of the scapula. The four active movements tested in this study were glenohumeral abduction, glenohumeral horizontal adduction, hand behind back, and forward reaching. The three bony landmarks were digitized six times in three different positions for each movement. Data from one subject were rejected secondary to pin loosening. The overall position-specific r.m.s. errors ranged from 2.0° to 12.5°. The full abduction position had considerably higher r.m.s. errors than the other positions (posterior tipping, 12.5°; upward rotation, 7.3°; internal rotation, 12.0°). It appears that the digitization of bony landmarks may be a valid method for measuring changes in scapular attitude with the following caveats: the full abduction position has a high r.m.s. error, and small scapular motions have high percentage errors.
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Re-estimated provincial HIV antenatal survey prevalence for 2007 and a reinterpretation of the national trend. S Afr Med J 2008; 98:940-941. [PMID: 19374069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
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Has HIV prevalence peaked in South Africa?--Can the report on the latest antenatal survey be trusted to answer this question? S Afr Med J 2008; 98:754-755. [PMID: 19115746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
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Decline in the prevalence of neural tube defects following folic acid fortification and its cost-benefit in South Africa. ACTA ACUST UNITED AC 2008; 82:211-6. [PMID: 18338391 DOI: 10.1002/bdra.20442] [Citation(s) in RCA: 148] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND In October 2003 South Africa embarked on a program of folic acid fortification of staple foods. We measured the change in prevalence of NTDs before and after fortification and assessed the cost benefit of this primary health care intervention. METHODS Since the beginning of 2002 an ecological study was conducted among 12 public hospitals in four provinces of South Africa. NTDs as well as other birth defect rates were reported before and after fortification. Mortality data were also collected from two independent sources. RESULTS This study shows a significant decline in the prevalence of NTDs following folic acid fortification in South Africa. A decline of 30.5% was observed, from 1.41 to 0.98 per 1,000 births (RR = 0.69; 95% CI: 0.49-0.98; p = .0379). The cost benefit ratio in averting NTDs was 46 to 1. Spina bifida showed a significant decline of 41.6% compared to 10.9% for anencephaly. Additionally, oro-facial clefts showed no significant decline (5.7%). An independent perinatal mortality surveillance system also shows a significant decline (65.9%) in NTD perinatal deaths, and in NTD infant mortality (38.8%). CONCLUSIONS The decrease in NTD rates postfortification is consistent with decreases observed in other countries that have fortified their food supplies. This is the first time this has been observed in a predominantly African population. The economic benefit flowing from the prevention of NTDs greatly exceeds the costs of implementing folic acid fortification.
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Bacterial community structure associated with the Antarctic soft coral, Alcyonium antarcticum. FEMS Microbiol Ecol 2007; 59:81-94. [PMID: 17233746 DOI: 10.1111/j.1574-6941.2006.00195.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The structure and composition of microbial communities inhabiting the soft coral Alcyonium antarcticum were investigated across three differentially contaminated sites within McMurdo Sound, Antarctica. Diverse microbial communities were revealed at all sites using culture-based analysis, denaturing gradient gel electrophoresis (DGGE), 16S rRNA gene clone-library analysis, and FISH. Phylogenetic analysis of isolates and retrieved sequences demonstrated close affiliation with known psychrophiles from the Antarctic environment and high similarity to Gammaproteobacteria clades of sponge-associated microorganisms. The majority of bacteria detected with all techniques reside within the Gammaproteobacteria, although other phylogenetic groups including Alpha- and Betaproteobacteria, Bacteroidetes, Firmicutes, Actinomycetales, Planctomycetes, and Chlorobi and bacteria from the functional group of sulfate-reducing bacteria were also present. Multivariate (nMDS) analysis of DGGE banding patterns and principal component analysis of quantitative FISH data revealed no distinct differences in community composition between differentially contaminated sites. Rather, conserved coral-associated bacterial groups were observed within and between sites, providing evidence to support specific coral-microbial interactions. This is the first investigation of microbial communities associated with Antarctic soft corals, and the results suggest that spatially stable microbial associations exist across an environmental impact gradient.
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Two steps forward, one step back: comment on adult mortality (age 15 - 64) based on death notification data in South Africa for 1997 - 2001. S Afr Med J 2006; 96:1028. [PMID: 17164931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023] Open
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'Four legs good, two legs bad'--political spin in the HIV prevalence survey. S Afr Med J 2006; 96:764. [PMID: 17076043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023] Open
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Photobacterium rosenbergii sp. nov. and Enterovibrio coralii sp. nov., vibrios associated with coral bleaching. Int J Syst Evol Microbiol 2005; 55:913-917. [PMID: 15774685 DOI: 10.1099/ijs.0.63370-0] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Six new Vibrio-like isolates originating from different species of bleached and healthy corals around Magnetic Island (Australia) were investigated using a polyphasic approach. Phylogenetic analyses based on 16S rRNA, recA and rpoA gene sequences split the isolates in two new groups. Strains LMG 22223(T), LMG 22224, LMG 22225, LMG 22226 and LMG 22227 were phylogenetic neighbours of Photobacterium leiognathi LMG 4228(T) (95.6 % 16S rRNA gene sequence similarity), whereas strain LMG 22228(T) was related to Enterovibrio norvegicus LMG 19839(T) (95.5 % 16S rRNA gene sequence similarity). The two new groups can be distinguished from closely related species on the basis of several phenotypic features, including fermentation of d-mannitol, melibiose and sucrose, and utilization of different compounds as carbon sources, arginine dihydrolase activity, nitrate reduction, resistance to the vibriostatic agent O/129 and the presence of fatty acids 15 : 0 iso and 17 : 0 iso. The names Photobacterium rosenbergii sp. nov. (type strain LMG 22223(T)=CBMAI 622(T)=CC1(T)) and Enterovibrio coralii sp. nov. (type strain LMG 22228(T)=CBMAI 623(T)=CC17(T)) are proposed to accommodate these new isolates. The G+C contents of the DNA of the two type strains are respectively 47.6 and 48.2 mol%.
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Abstract
OBJECTIVE To quantify the HIV/AIDS deaths misclassified to AIDS-related conditions in South Africa. DESIGN Retrospective analysis of vital registration data. METHODS Cause-specific death rates for 1996 and 2000-2001 were calculated using vital registration cause-of-death profiles applied to a model (ASSA2000) estimate of total mortality rates by age and sex. The difference in the age-specific death rates for these two periods was examined to identify conditions where there was a noticeable increase in mortality following the same age pattern as the HIV deaths, thus likely to be misclassified AIDS deaths. RESULTS The increase in the age-specific death rates for HIV-related deaths showed a distinct age pattern, which has been observed elsewhere. Out of the 22 potential causes of death investigated, there were nine that increased in the same distinct age pattern (tuberculosis, pneumonia, diarrhoea, meningitis, other respiratory disease, non-infective gastroenteritis, other infectious and parasitic diseases, deficiency anaemias and protein energy malnutrition) and could be considered AIDS-related conditions. The increase in these conditions accounted for 61% of the total deaths related to HIV/AIDS. When added to the deaths classified as HIV-related on the death certificate, the total accounts for 93% of the ASSA2000 model estimates of the number of AIDS deaths in 2000. CONCLUSION As a large proportion of AIDS deaths appear to be classified to AIDS-related conditions, without reference to HIV, interpretation of death statistics in South Africa cannot be made on face value as a large proportion of deaths caused by HIV infection are misclassified.
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Guillain-Barre Syndrome in a Rural Farming District in South Africa: A Possible Relationship to Environmental Organophosphate Exposure. ACTA ACUST UNITED AC 2004; 59:575-80. [PMID: 16599005 DOI: 10.1080/00039890409603436] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Although organophosphate (OP) insecticides have been recognized as having neuropathic potential, a relationship with Guillain-Barre syndrome (GBS) has not been previously confirmed. A cluster of 7 cases of GBS was noted over an 11-yr period in an isolated farming region in the Northern Cape Province of South Africa, an area subject to intensive aerial application of OP insecticides. Observed cases were more than 4 times higher than expected based on a Poisson probability distribution. Four cases were clustered in an area where the topography showed a marked hollow, and where spray drift of aerial OP insecticides was anticipated. The rate of GBS in this subcluster was more than 14 times higher than expected. The authors explored the hypothesis that aerial OP insecticide application was related to the raised incidence of GBS in this area and made suggestions for future research.
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Whither the AIDS epidemic--or lies, damned lies and statistics? S Afr Med J 2003; 93:916-7. [PMID: 14750490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023] Open
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Abstract
A 63 year old man presented with the signs of acute generalised peritonism in the presence of a clear chest radiograph. At laparotomy no abnormal findings were noted. Further inquiries revealed a history of recent acquisition of budgerigars, over the following days the chest radiograph developed patchy opacification. Subsequently IgG immunofluorescence confirmed the diagnosis of Chlamydia psittaci. The presentation of psittacosis with gastrointestinal features is well recognised. This is believed to be the first account in the literature of a human case of Chl psittaci pneumonia presenting with acute generalised peritonism indicating an exploratory laparotomy. It is suggested that Chl psittaci pneumonia should be considered in the differential diagnosis of an acute abdomen in the presence of a history of exposure to psittacine birds.
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The current state and future projections of the HIV/AIDS epidemic in South Africa. SADJ : JOURNAL OF THE SOUTH AFRICAN DENTAL ASSOCIATION = TYDSKRIF VAN DIE SUID-AFRIKAANSE TANDHEELKUNDIGE VERENIGING 2002; 57:449-50. [PMID: 12674863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
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Abstract
WN virus is one of the most ubiquitous arboviruses occurring over a broad geographical range and in a wide diversity of vertebrate host and vector species. The virus appears to be maintained in endemic foci on the African continent and is transported annually to temperate climates to the north in Europe and to the south in South Africa. Reports of clinical disease due to natural WN virus infection in wild or domestic animals were much less common than reports of infection (virus isolation or antibody detection). Until recently, records of morbidity and mortality in wild birds were confined to a small number of cases and infections causing encephalitis, sometimes fatal, in horses were reported infrequently. In the period 1996-2001, there was an increase in outbreaks of illness due to WN virus in animals as well as humans. Within the traditional range of WN virus, encephalitis was reported in horses in Italy in 1998 and in France in 2000. The first report of disease and deaths caused by WN virus infection in domestic birds was reported in Israel in 1997-1999, involving hundreds of young geese. In 1999 WN virus reached North America and caused an outbreak of encephalitis in humans in the New York area at the same time as a number of cases of equine encephalitis and deaths in American crows and a variety of other bird species, both North American natives and exotics. Multi-state surveillance for WN virus has been in place since April 2000 and has resulted in the detection of WN virus in thousands of dead birds from an increasing number of species in North America, and also in several species of mammals. The surveillance system that has developed in North America because of the utility of testing dead birds for the rapid detection of WN virus presence has been a unique integration of public health and wildlife health agencies. It has been suggested that the recent upsurge in clinical WN virus infection in wild and domestic animals as well as in humans may be related to the emergence of one or more new strains of WN virus. Virus isolated in New York in 1999 was found to be identical to that from Israel. It was alarming for WN virus to so easily invade the United States and surprising that it became established so quickly in the temperature climate of New York. Its persistence and rapid expansion in the United States leave a number of unanswered questions. New disease characteristics and patterns have occurred and more are evolving as WN virus further invades the western hemisphere. Additional animal research is needed to answer these questions. Some of the research needs include bird migration as a mechanism of virus dispersal, vector and vertebrate host relationships, virus persistence mechanisms, laboratory diagnosis, viral pathogenesis, risk factor studies, vaccine development, and WN virus impact on wildlife (CDC 2001a). Determination of the primary reservoir host species that are involved in the epidemiology of WN virus and the suitable sentinel species for active surveillance are also important research areas.
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Informed consent and the placement of percutaneous endoscopic gastrostomy tubes. ARCHIVES OF INTERNAL MEDICINE 2001; 161:2506-7. [PMID: 11700169 DOI: 10.1001/archinte.161.20.2506] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Modelling control strategies for foot-and-mouth disease. Vet Rec 2001; 149:249-50; author reply 251-2. [PMID: 11554573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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Catheter ablation for cardiac arrhythmias. Ablation should not be denied to elderly patients on basis of age. BMJ (CLINICAL RESEARCH ED.) 2001; 322:613. [PMID: 11269255 PMCID: PMC1119800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Flavor threshold for acetaldehyde in milk, chocolate milk, and spring water using solid phase microextraction gas chromatography for quantification. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2001; 49:1377-1381. [PMID: 11312867 DOI: 10.1021/jf001069t] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The detection threshold of acetaldehyde was determined on whole, lowfat, and nonfat milks, chocolate-flavored milk, and spring water. Knowledge of the acetaldehyde threshold is important because acetaldehyde forms in milk during storage as a result of light oxidation. It is also a degradation product of poly(ethylene terephthalate) during melt processing, a relatively new packaging choice for milk and water. There was no significant difference in the acetaldehyde threshold in milk of various fat contents, with thresholds ranging from 3939 to 4040 ppb. Chocolate-flavored milk and spring water showed thresholds of 10048 and 167 ppb, respectively, which compares favorably with previous studies. Solid phase microextraction (SPME) was verified as an effective method for the recovery of acetaldehyde in all media with detection levels as low as 200 and 20 ppb in milk and water, respectively, when using a polydimethyl siloxane/Carboxen SPME fiber in static headspace at 45 degrees C for 15 min.
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HIV surveillance results--little grounds for optimism yet. S Afr Med J 2000; 90:452-3. [PMID: 10901807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
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Abstract
Post mastectomy pain syndrome is a condition which can occur following breast surgery and has until recently been regarded as uncommon. Recent reports have suggested that it may affect 20% or more of women following mastectomy. The symptoms are distressing and may be difficult to treat however treatment for neuropathic pain can be successful. This paper reports a retrospective cohort of consecutive mastectomy cases over a six year period in one region of whom 511 survivors were traced and eligible for survey. A total of 408 completed a questionnaire survey which revealed that 175 (43%) had ever suffered from postmastectomy pain syndrome and 119 (29%) reported current symptoms although the majority were decreasing in intensity. A striking finding was the very high cumulative prevalence in younger women (65%) decreasing to 26% in the over 70 year group. The details of the onset, frequency and intensity of symptoms are described along with their natural history. The age effect on the frequency of the syndrome influences the marital status, employment status, housing, and educational status of those who report typical symptoms. Body weight and height are also associated with the frequency of post mastectomy pain syndrome. Relationship between the frequency of post mastectomy pain syndrome and radiotherapy, chemotherapy and the use of tamoxifen are difficult to unravel because of the combinations of pre and post operative treatments received confounded by age. The implications of a much higher frequency of post mastectomy pain are discussed with regard to management and counselling. The high frequency of the syndrome in the younger women is important and possible explanations are explored.
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Some spatial variations in South African mortality. URBANISATION AND HEALTH NEWSLETTER 1996:29-32. [PMID: 12178475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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Abstract
BACKGROUND Cervical cancer is an important cause of death throughout the world, especially in less developed countries. Reports of trends in cervical cancer mortality from less developed countries have been limited by poor data quality and inaccurate population estimates. This paper examines trends in cervical cancer mortality in South Africa from 1949 to 1990 and discusses the impact of cytology screening on these trends. METHODS Analysis of national mortality statistics and reconstructed population data. RESULTS The age-standardized mortality rates for Whites declined after the mid 1960s, while that for Coloureds rose, particularly before the 1970s. These trends were affected predominantly by trends among women in the 35-64 age range. CONCLUSIONS The pattern of mortality in successive birth cohorts for Whites is consistent with a reduction in age-specific mortality following the advent of cytological screening. The same pattern is not evident in trends for Coloureds, among whom screening has apparently had a minor impact if any at all. The apparent lack of impact of screening in those groups of women most at risk of cervical cancer lends weight to demands for the implementation of equitable and rational screening programmes for cervical cancer in South Africa and internationally.
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Abstract
BACKGROUND The opportunistic basis on which screening has been conducted in South Africa has resulted in multiple rescreening of a small proportion of the population (which excludes most women at high risk) and low population coverage. There has consequently been a failure of screening to impact on the incidence of cervical cancer in most of the population. AIM To propose the use of the ratio of smears showing cervical intra-epithelial neoplasia (CIN)III: smears showing signs of malignancy as an indicator for the surveillance of equity in cervical cytology screening, and to apply this indicator to an area of the Western Cape of South Africa. RESULTS Marked inequity in screening is demonstrated between metropolitan and non-metropolitan area, and between different non-metropolitan districts. Inequity in screening between different age groups of women is also found, and this is associated with an inappropriately young age distribution of screening activity. CONCLUSIONS The application of this indicator in the routine surveillance of screening activity may be useful in monitoring progress towards the implementation of more equitable screening programmes, and the validity of the indicator should be tested in other settings.
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