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Descriptive analysis of horses and ponies attending horse auctions in Victoria from July 2019 to March 2020. Aust Vet J 2023; 101:1-8. [PMID: 36176071 PMCID: PMC10087768 DOI: 10.1111/avj.13210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 08/20/2022] [Accepted: 09/09/2022] [Indexed: 02/04/2023]
Abstract
INTRODUCTION In recent years there has been public speculation about the breed, destination and number of horses being sold by public auction at livestock saleyards in Australia. Currently, there is little objective information available about the breed and condition of horses sold through this medium. With little publicly available objective data on these horses, the horse industry has been left vulnerable to misinformation. Accurate information regarding the composition and condition of horses attending saleyards is important to identify and address any welfare issues and to inform public debate. METHOD Data were collected on 312 horses and ponies presented for sale through the Pakenham Horse Sales between July 2019 and March 2020. All horses and ponies were inspected at the saleyards and information on breed, age, body condition score (BCS), purchaser and sale price were recorded as the animals were auctioned. RESULTS Crossbred horses and ponies were the largest groups presented for sale. Ponies were more likely to be sold to private buyers. Quarter horses and riding ponies were as likely to be sent to slaughter as thoroughbreds and standardbreds. Entire males and females sold for lower prices than geldings. Most horses and ponies (64%) were sold to private buyers. More than three-quarters (77%) of horses and ponies presented for sale had a BCS greater than or equal to three out of five. CONCLUSION This pilot study challenges perceptions that thoroughbreds are the primary breed to attend public sales or that animals attending the sales are in poor condition.
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Changes in Ozone Chemical Sensitivity in the United States from 2007 to 2016. ACS ENVIRONMENTAL AU 2022; 2:206-222. [PMID: 35967933 PMCID: PMC9371464 DOI: 10.1021/acsenvironau.1c00029] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Anthropogenic nitrogen oxide (NOx) and volatile organic compound (VOC) emissions in the U.S. have declined substantially over the last decade, altering the NOx-VOC chemistry and ozone (O3) production characteristics of many areas. In this work we use multiple air quality analysis tools to assess how these large reductions in NOx and VOC have affected O3 production regimes across the U.S. between 2007 and 2016. We first compare observed and modeled evolution of NOx-limited and NOx-saturated O3 formation regimes using a day-of-week (DOW) analysis. This comparison builds confidence in the model's ability to qualitatively capture O3 changes due to chemistry and meteorology both within years and across periods of large emissions decreases. DOW analysis, however, cannot definitively differentiate between emissions and meteorology impacts. We therefore supplement this analysis with sensitivity calculations from CAMx-HDDM to characterize modeled shifts in O3 formation chemistry between 2007 and 2016 in different regions of the U.S. We also conduct a more detailed investigation of the O3 chemical behavior observed in Chicago and Detroit, two complex urban areas in the Midwest. Both the ambient and modeling data show that more locations across the U.S. have shifted towards NOx-limited regimes between 2007 and 2016. The model-based HDDM sensitivity analysis shows only a few locations remaining NOx-saturated on high-O3 days in 2016 including portions of New York City, Chicago, Minneapolis, San Francisco and Los Angeles. This work offers insights into the current state of O3 production chemistry in large population centers across the U.S., as well as how O3 chemistry in these areas may evolve in the future.
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Improved Estimation of Trends in U.S. Ozone Concentrations Adjusted for Interannual Variability in Meteorological Conditions. ATMOSPHERIC ENVIRONMENT (OXFORD, ENGLAND : 1994) 2021; 248:118234. [PMID: 33776540 PMCID: PMC7995240 DOI: 10.1016/j.atmosenv.2021.118234] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Daily maximum 8-hour average (MDA8) ozone (O3) concentrations are well-known to be influenced by local meteorological conditions, which vary across both daily and seasonal temporal scales. Previous studies have adjusted long-term trends in O3 concentrations for meteorological effects using various statistical and mathematical methods in order to get a better estimate of the long-term changes in O3 concentrations due to changes in precursor emissions such as nitrogen oxides (NOX) and volatile organic compounds (VOCs). In this work, the authors present improvements to the current method used by the United States Environmental Protection Agency (US EPA) to adjust O3 trends for meteorological influences by making refinements to the input data sources and by allowing the underlying statistical model to vary locally using a variable selection procedure. The current method is also expanded by using a quantile regression model to adjust trends in the 90th and 98th percentiles of the distribution of MDA8 O3 concentrations, allowing for a better understanding of the effects of local meteorology on peak O3 levels in addition to seasonal average concentrations. The revised method is used to adjust trends in the May to September mean, 90th percentile, and 98th percentile MDA8 O3 concentrations at over 700 monitoring sites in the U.S. for years 2000 to 2016. The utilization of variable selection and quantile regression allow for a more in-depth understanding of how weather conditions affect O3 levels in the U.S. This represents a fundamental advancement in our ability to understand how interannual variability in weather conditions in the U.S. may impact attainment of the O3 National Ambient Air Quality Standards (NAAQS).
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Uncertainty associated with ambient ozone metrics in epidemiologic studies and risk assessments. AIR QUALITY, ATMOSPHERE, & HEALTH 2019; 12:585-595. [PMID: 32601527 PMCID: PMC7321928 DOI: 10.1007/s11869-019-00679-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 02/12/2019] [Indexed: 06/11/2023]
Abstract
Epidemiologic studies relating ambient ozone concentrations to adverse health outcomes have typically relied on spatial averages of concentrations from nearby monitoring stations, referred to as "composite monitors." This practice reflects the assumption that ambient ozone concentrations within an urban area are spatially homogenous. We tested the validity of this assumption by comparing ozone data measured at individual monitoring sites within selected US urban areas to their respective composite monitor time series. We first characterized the temporal correlation between the composite monitor and individual monitors in each area. Next, we analyzed the heteroskedasticity of each relationship. Finally, we compared the distribution of concentrations measured at individual monitors to the composite monitor distribution. Individual monitors showed high correlation with the composite monitor over much of the range of ambient ozone concentrations, though correlations were lower at higher concentrations. The variance between individual monitors and the composite monitor increased as a function of concentration in nearly all the urban areas. Finally, we observed statistical bias in the composite monitor concentrations at the high end of the distribution. The degree to which these results introduce uncertainty into studies that utilize composite monitors depends on the contributions of peak ozone concentrations to reported health effect associations.
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A phase I study of HERV-E TCR transduced autologous T Cells (HERV-E TCR T Cells) in patients (pts) with metastatic clear cell renal cell carcinoma (mccRCC). Ann Oncol 2018. [DOI: 10.1093/annonc/mdy283.133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Tropospheric ozone assessment report: Global ozone metrics for climate change, human health, and crop/ecosystem research. ELEMENTA (WASHINGTON, D.C.) 2018; 1:1. [PMID: 30345319 PMCID: PMC6192432 DOI: 10.1525/elementa.279] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Assessment of spatial and temporal variation in the impacts of ozone on human health, vegetation, and climate requires appropriate metrics. A key component of the Tropospheric Ozone Assessment Report (TOAR) is the consistent calculation of these metrics at thousands of monitoring sites globally. Investigating temporal trends in these metrics required that the same statistical methods be applied across these ozone monitoring sites. The nonparametric Mann-Kendall test (for significant trends) and the Theil-Sen estimator (for estimating the magnitude of trend) were selected to provide robust methods across all sites. This paper provides the scientific underpinnings necessary to better understand the implications of and rationale for selecting a specific TOAR metric for assessing spatial and temporal variation in ozone for a particular impact. The rationale and underlying research evidence that influence the derivation of specific metrics are given. The form of 25 metrics (4 for model-measurement comparison, 5 for characterization of ozone in the free troposphere, 11 for human health impacts, and 5 for vegetation impacts) are described. Finally, this study categorizes health and vegetation exposure metrics based on the extent to which they are determined only by the highest hourly ozone levels, or by a wider range of values. The magnitude of the metrics is influenced by both the distribution of hourly average ozone concentrations at a site location, and the extent to which a particular metric is determined by relatively low, moderate, and high hourly ozone levels. Hence, for the same ozone time series, changes in the distribution of ozone concentrations can result in different changes in the magnitude and direction of trends for different metrics. Thus, dissimilar conclusions about the effect of changes in the drivers of ozone variability (e.g., precursor emissions) on health and vegetation exposure can result from the selection of different metrics.
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Assessing Temporal and Spatial Patterns of Observed and Predicted Ozone in Multiple Urban Areas. ENVIRONMENTAL HEALTH PERSPECTIVES 2016; 124:1443-52. [PMID: 27153213 PMCID: PMC5010397 DOI: 10.1289/ehp190] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Revised: 12/17/2015] [Accepted: 04/27/2016] [Indexed: 05/22/2023]
Abstract
BACKGROUND Ambient monitoring data show spatial gradients in ozone (O3) across urban areas. Nitrogen oxide (NOx) emissions reductions will likely alter these gradients. Epidemiological studies often use exposure surrogates that may not fully account for the impacts of spatially and temporally changing concentrations on population exposure. OBJECTIVES We examined the impact of large NOx decreases on spatial and temporal O3 patterns and the implications on exposure. METHODS We used a photochemical model to estimate O3 response to large NOx reductions. We derived time series of 2006-2008 O3 concentrations consistent with 50% and 75% NOx emissions reduction scenarios in three urban areas (Atlanta, Philadelphia, and Chicago) at each monitor location and spatially interpolated O3 to census-tract centroids. RESULTS We predicted that low O3 concentrations would increase and high O3 concentrations would decrease in response to NOx reductions within an urban area. O3 increases occurred across larger areas for the seasonal mean metric than for the regulatory metric (annual 4th highest daily 8-hr maximum) and were located only in urban core areas. O3 always decreased outside the urban core (e.g., at locations of maximum local ozone concentration) for both metrics and decreased within the urban core in some instances. NOx reductions led to more uniform spatial gradients and diurnal and seasonal patterns and caused seasonal peaks in midrange O3 concentrations to shift from midsummer to earlier in the year. CONCLUSIONS These changes have implications for how O3 exposure may change in response to NOx reductions and are informative for the design of future epidemiology studies and risk assessments. CITATION Simon H, Wells B, Baker KR, Hubbell B. 2016. Assessing temporal and spatial patterns of observed and predicted ozone in multiple urban areas. Environ Health Perspect 124:1443-1452; http://dx.doi.org/10.1289/EHP190.
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Development of a sensitive method to extract and detect low numbers of Cryptosporidium oocysts from adult cattle faecal samples. Vet Parasitol 2016; 227:26-9. [DOI: 10.1016/j.vetpar.2016.07.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 07/12/2016] [Accepted: 07/15/2016] [Indexed: 11/24/2022]
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Ozone trends across the United States over a period of decreasing NOx and VOC emissions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:186-95. [PMID: 25517137 DOI: 10.1021/es504514z] [Citation(s) in RCA: 115] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
In this work, we evaluate ambient ozone trends at urban, suburban, and rural monitoring sites across the United States over a period of decreasing NOx and VOC emissions (1998-2013). We find that decreasing ozone trends generally occur in the summer, in less urbanized areas, and at the upper end of the ozone distribution. Conversely, increasing ozone trends generally occur in the winter, in more urbanized areas, and at the lower end of the ozone distribution. The 95(th) percentile ozone concentrations decreased at urban, suburban, and rural monitors by 1-2 ppb/yr in the summer and 0.5-1 ppb/yr in the winter. In the summer, there are both increasing and decreasing trends in fifth percentile ozone concentrations of less than 0.5 ppb/yr at urban and suburban monitors, while fifth percentile ozone concentrations at rural monitors decreased by up to 1 ppb/yr. In the winter, fifth percentile ozone concentrations generally increased by 0.1-1 ppb/yr. These results demonstrate the large scale success of U.S. control strategies targeted at decreasing peak ozone concentrations. In addition, they indicate that as anthropogenic NOx emissions have decreased, the ozone distribution has been compressed, leading to less spatial and temporal variability.
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PP53 A qualitative study of the adoption of computerised clinical decision support (CCDS) by paramedics and its impact on their role and practice. Br J Soc Med 2014. [DOI: 10.1136/jech-2014-204726.148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Hyperbolic and plasmonic properties of silicon/Ag aligned nanowire arrays. OPTICS EXPRESS 2013; 21:14962-14974. [PMID: 23787684 DOI: 10.1364/oe.21.014962] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The hyperbolic and plasmonic properties of silicon nanowire/Ag arrays have been investigated. The aligned nanowire arrays were formed and coated by atomic layer deposition of Ag, which itself is a metamaterial due to its unique mosaic film structure. The theoretical and numerical studies suggest that the fabricated arrays have hyperbolic dispersion in the visible and IR ranges of the spectrum. The theoretical predictions have been indirectly confirmed by polarized reflection spectra, showing reduction of the reflection in p polarization in comparison to that in s polarization. Studies of dye emission on top of Si/Ag nanowire arrays show strong emission quenching and shortening of dye emission kinetics. This behavior is also consistent with the predictions for hyperbolic media. The measured SERS signals were enhanced by almost an order of magnitude for closely packed and aligned nanowires, compared to random nanowire composites. These results agree with electric field simulations of these array structures.
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Development of a chick bioassay for determination of infectivity of viral pathogens in poultry litter. Aust Vet J 2013; 91:65-71. [PMID: 23356376 DOI: 10.1111/avj.12010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/07/2012] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To develop a chicken bioassay to detect infective viral pathogens in poultry litter and to determine the effects of type of chicken and age of exposure, as well as the effect of simulated litter transportation, on the level of viral infectivity detected. DESIGN A 5 × 2 × 2 factorial design, plus negative controls. Five chicken litters, including two with deliberate contamination (one transported and one not), two chicken types (specific-pathogen-free (SPF) Leghorns and Cobb broilers) and two ages at initial exposure (days 1 and 8). Two replicates of each treatment combination. METHODS The 10 chickens in each of 22 isolators were either exposed (20 isolators) or not (2 isolators) to 8 L of previously used or deliberately contaminated poultry litter in two deep scratch trays. At day 35 post-exposure, sera were assayed for antibodies against chicken anaemia virus (CAV), infectious bronchitis virus (IBV), infectious bursal disease virus (IBDV), Newcastle disease virus (NDV) and fowl adenovirus (FAV). Spleen samples were tested for Marek's disease virus (MDV) using real-time polymerase chain reaction. RESULTS The bioassay detected CAV, IBDV and FAV, but not NDV, IBV or MDV, in chickens exposed to infected litters. Infection in SPF chickens was detected with greater sensitivity than in the broiler chickens. Sensitivity increased with age at exposure in broiler but not SPF chickens. Simulated transportation for 24 h had little effect on pathogen detection. CONCLUSION A bioassay based on the exposure of day-old SPF chickens to poultry litter and measurement of seroconversion at day 35 post-exposure is a useful semi-quantitative assay for viral infectivity in poultry litter, with overnight transportation of litter having little effect on the level of viral infectivity detected. This bioassay has applications in research on litter treatment protocols.
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A direct sensitivity approach to predict hourly ozone resulting from compliance with the National Ambient Air Quality Standard. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:2304-2313. [PMID: 23256562 DOI: 10.1021/es303674e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
In setting primary ambient air quality standards, the EPA's responsibility under the law is to establish standards that protect public health. As part of the current review of the ozone National Ambient Air Quality Standard (NAAQS), the US EPA evaluated the health exposure and risks associated with ambient ozone pollution using a statistical approach to adjust recent air quality to simulate just meeting the current standard level, without specifying emission control strategies. One drawback of this purely statistical concentration rollback approach is that it does not take into account spatial and temporal heterogeneity of ozone response to emissions changes. The application of the higher-order decoupled direct method (HDDM) in the community multiscale air quality (CMAQ) model is discussed here to provide an example of a methodology that could incorporate this variability into the risk assessment analyses. Because this approach includes a full representation of the chemical production and physical transport of ozone in the atmosphere, it does not require assumed background concentrations, which have been applied to constrain estimates from past statistical techniques. The CMAQ-HDDM adjustment approach is extended to measured ozone concentrations by determining typical sensitivities at each monitor location and hour of the day based on a linear relationship between first-order sensitivities and hourly ozone values. This approach is demonstrated by modeling ozone responses for monitor locations in Detroit and Charlotte to domain-wide reductions in anthropogenic NOx and VOCs emissions. As seen in previous studies, ozone response calculated using HDDM compared well to brute-force emissions changes up to approximately a 50% reduction in emissions. A new stepwise approach is developed here to apply this method to emissions reductions beyond 50% allowing for the simulation of more stringent reductions in ozone concentrations. Compared to previous rollback methods, this application of modeled sensitivities to ambient ozone concentrations provides a more realistic spatial response of ozone concentrations at monitors inside and outside the urban core and at hours of both high and low ozone concentrations.
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Canadian Surgery Forum1 Is laparoscopic sleeve gastrectomy a reasonable stand-alone procedure for super morbidly obese patients?2 Postoperative monitoring requirements of patients with obstructive sleep apnea undergoing bariatric surgery3 Role of relaparoscopy in the diagnosis and treatment of bariatric complications in the early postoperative period4 Changes of active and total ghrelin, GLP-1 and PYY following restrictive bariatric surgery and their impact on satiety: comparison of sleeve gastrectomy and adjustable gastric banding5 Prioritization and willingness to pay for bariatric surgery: the patient perspective6 Ventral hernia at the time of laparoscopic gastric bypass surgery: Should it be repaired?7 Linear stapled gastrojejunostomy with transverse handsewn enterotomy closure significantly reduces strictures for laparoscopic Roux-en-Y bypass8 Laparoscopic biliopancreatic diversion with duodenal switch as second stage for super super morbidly obese patients. Do all patients benefit?9 Sleeve gastrectomy in the super super morbidly obese (BMI > 60 kg/m2): a Canadian experience10 Laparoscopic gastric bypass for the treatment of refractory idiopathic gastroparesis: a report of 2 cases11 Duodeno-ileal switch as a primary bariatric and metabolic surgical option for the severely obese patient with comorbidities: review of a single-institution case series of duodeno-ileal intestinal bypass12 Management of large paraesophageal hernias in morbidly obese patients with laparoscopic sleeve gastrectomy: a case series13 Early results of the Ontario bariatric surgical program: using the bariatric registry14 Improving access to bariatric surgical care: Is universal health care the answer?15 Early and liberal postoperative exploration can reduce morbidity and mortality in patients undergoing bariatric surgery16 Withdrawn17 Identification and assessment of technical errors in laparoscopic Roux-en-Y gastric bypass18 A valid and reliable tool for assessment of surgical skill in laparoscopic Roux-en-Y gastric bypass19 Psychiatric predictors of presurgery drop-out following suitability assessment for bariatric surgery20 Predictors of outcomes following Roux-en-Y gastric bypass surgery at The Ottawa Hospital21 Prophylactic management of cholelithiasis in bariatric patients: Is routine cholecystectomy warranted?22 Early outcomes of Roux-en-Y gastric bypass in a publicly funded obesity program23 Similar incidence of gastrojejunal anastomotic stricture formation with hand-sewn and 21 mm circular stapler techniques during Roux-en-Y gastric bypass24 (CAGS Basic Science Award) Exogenous glucagon-like peptide-1 improves clinical, morphological and histological outcomes of intestinal adaptation in a distal-intestinal resection piglet model of short bowel syndrome25 (CAGS Clinical Research Award) Development and validation of a comprehensive curriculum to teach an advanced minimally invasive procedure: a randomized controlled trial26 Negative-pressure wound therapy (iVAC) on closed, high-risk incisions following abdominal wall reconstruction27 The impact of seed granting on research in the University of British Columbia Department of Surgery28 Quality of surgical care is inadequate for elderly patients29 Recurrence of inguinal hernia in general and hernia specialty hospitals in Ontario, Canada30 Oncostatin M receptor deficiency results in increased mortality in an intestinal ischemia reperfusion model in mice31 Laparoscopic repair of large paraesophageal hernias with anterior gastropexy: a multicentre trial32 Response to preoperative medical therapy predicts success of laparoscopic splenectomy for immune thrombocytopenic purpura33 Perioperative sepsis, but not hemorrhagic shock, promotes the development of cancer metastases in a murine model34 Measuring the impact of implementing an acute care surgery service on the management of acute biliary disease35 Patient flow and efficiency in an acute care surgery service36 The relationship between treatment factors and postoperative complications after radical surgery for rectal cancer37 Risk of ventral hernia after laparoscopic colon surgery38 Urinary metabolomics as a tool for early detection of Barrett’s and esophageal cancer39 Construct validity of individual and summary performance metrics associated with a computer-based laparo-scopic simulator40 Impact of a city-wide health system reorganization on emergency department visits in hospitals in surrounding communities41 Transcatheter aortic valve implantation for the nonoperative management of aortic stenosis: a cost-effectiveness analysis42 Breast cancer: racial differences in age of onset. A potential confounder in Canadian screening recommendations43 Risk taking in surgery: in and out of the comfort zone44 A tumour board in the office: Track those cancer patients!45 Increased patient BMI is not associated with advanced colon cancer stage or grade on presentation: a retrospective chart review46 Consensus statements regarding the multidisciplinary care of limb amputation patients in disasters or humanitarian emergencies. Report of the 2011 Humanitarian Action Summit Surgical Working Group on amputations following disasters or conflict47 Learning the CanMEDS role of professional: a pilot project of supervised discussion groups addressing the hidden curriculum48 Assessing the changing scope of training in Canadian general surgery programs: expected versus actual experience49 Predicting need for surgical management for massive gastrointestinal hemorrhage50 International health care experience: using CanMEDS to evaluate learning outcomes following a surgical mission in Mampong, Ghana51 The open abdomen: risk factors for mortality and rates of closure52 How surgeons think: an exploration of mental practice in surgical preparation53 The surgery wiki: a novel method for delivery of under-graduate surgical education54 Understanding surgical residents’ postoperative practices before implementing an enhanced recovery after surgery (ERAS) guideline at the University of Toronto55 From laparoscopic transabdominal to posterior retroperitoneal adrenalectomy: a paradigm shift in operative approach56 A retrospective audit of outcomes in patients over the age of 80 undergoing acute care abdominal surgery57 Canadian general surgery residents’ perspectives on work-hour regulations58 Timing of surgical intervention and its outcomes in acute appendicitis59 Preparing surgical trainees to deal with adverse events. An outline of learning issues60 Acute care surgical service: surgeon agreement at the time of handover61 Predicting discharge of elderly patients to prehospitalization residence following emergency general surgery62 Morbidity and mortality after emergency abdominal surgery in octo- and nonagenarians63 The impact of acute abdominal illness and urgent admission to hospital on the living situation of elderly patients64 A comparison of laparoscopic versus open subtotal gastrectomy for antral gastric adenocarcinoma: a North American perspective65 Minimally invasive excision of ectopic mediastinal parathyroid adenomas66 Perioperative outcomes of laparoscopic hernia repair in a tertiary care centre: a single institution’s experience67 Evaluation of a student-run, practical and didactic curriculum for preclerkship medical students68 Joseph Lister: Father of Modern Surgery69 Comparisons of melanoma sentinel lymph node biopsy prediction nomograms in a cohort of Canadian patients70 Local experience with myocutaneous flaps after extensive pelvic surgery71 The treatment of noncirrhotic splanchnic vein thrombosis: Is anticoagulation enough?72 Implementation of an acute care surgery service does not affect wait-times for elective cancer surgeries: an institutional experience73 Use of human collagen mesh for closure of a large abdominal wall defect, after colon cancer surgery, a case report74 The role of miR-200b in pulmonary hypoplasia associated with congenital diaphragmatic hernia75 Systematic review and meta-analysis of electrocautery versus scalpel for incising epidermis and dermis76 Accuracy of sentinel lymph node biopsy for early breast cancer in the community setting in St. John’s, New-foundland: results of a retrospective review77 Acute surgical outcomes in the 80 plus population78 The liberal use of platelets transfusions in the acute phase of trauma resuscitation: a systematic review79 Implementation of an acute care surgical on call program in a Canadian community hospital80 Short-term outcomes following paraesophageal hernia repair in the elderly patient81 First experience with single incision surgery: feasibility in the pediatric population and cost evaluation82 The impact of the establishment of an acute care surgery unit on the outcomes of appendectomies and cholecystectomies83 Description and preliminary evaluation of a low-cost simulator for training and evaluation of flexible endoscopic skills84 Tumour lysis syndrome in metastatic colon cancer: a case report85 Acute care surgery service model implementation study at a single institution86 Colonic disasters approached by emergent subtotal and total colectomy: lessons learned from 120 consecutive cases87 Acellular collagen matrix stent to protect bowel anastomoses88 Lessons we learned from preoperative MRI-guided wire localization of breast lesions: the University Health Network (UHN) experience89 Interim cost comparison for the use of platinum micro-coils in the operative localization of small peripheral lung nodules90 Routine barium esophagram has minimal impact on the postoperative management of patients undergoing esophagectomy for esophageal cancer91 Iron deficiency anemia is a common presenting issue with giant paraesophageal hernia and resolves following repair92 A randomized comparison of different ventilation strategies during thoracotomy and lung resection93 The Canadian Lung Volume Reduction Surgery study: an 8-year follow-up94 A comparison of minimally invasive versus open Ivor-Lewis esophagectomy95 A new paradigm in the follow-up after curative resection for lung cancer: minimal-dose CT scan allows for early detection of asymptomatic cancer activity96 Predictors of lymph node metastasis in early esophageal adenocarcinoma: Is endoscopic resection worth the risk?97 How well can thoracic surgery residents operate? Comparing resident and program director opinions98 The impact of extremes of age on short- and long-term outcomes following surgical resection of esophageal malignancy99 Epidermal growth factor receptor targeted gold nanoparticles for the enhanced radiation treatment of non–small cell lung cancer100 Laparoscopic Heller myotomy results in excellent outcomes in all subtypes of achalasia as defined by the Chicago classification101 Neoadjuvant chemoradiation versus surgery in managing esophageal cancer102 Quality of life postesophagectomy for cancer!103 The implementation, evolution and translocation of standardized clinical pathways can improve perioperative outcomes following surgical treatment of esophageal cancer104 A tissue-mimicking phantom for applications in thoracic surgical simulation105 Sublobar resection compared with lobectomy for early stage non–small cell lung cancer: a single institution study106 Not all reviews are equal: the quality of systematic reviews and meta-analyses in thoracic surgery107 Do postoperative complications affect health-related quality of life after video-assisted thoracoscopic lobectomy for patients with lung cancer? A cohort study108 Thoracoscopic plication for palliation of dyspnea secondary to unilateral diaphragmatic paralysis: A worthwhile venture?109 Thoracic surgery experience in Canadian general surgery residency programs110 Perioperative morbidity and pathologic response rates following neoadjuvant chemotherapy and chemoradiation for locally advanced esophageal carcinoma111 An enhanced recovery pathway reduces length of stay after esophagectomy112 Predictors of dysplastic and neoplastic progression of Barrett’s esophagus113 Recurrent esophageal cancer complicated by tracheoesophageal fistula: management by means of palliative airway stenting114 Pancreaticopleural fistula-induced empyema thoracis: principles and results of surgical management115 Prognostic factors of early postoperative mortality following right extended hepatectomy116 Optimizing steatotic livers for transplantation using a cell-penetrating peptide CPP-fused heme oxygenase117 Video outlining the technical steps for a robot-assisted laparoscopic pancreaticoduodenectomy118 Establishment of a collaborative group to conduct innovative clinical trials in Canada119 Hepatic resection for metastatic malignant melanoma: a systematic review and meta-analysis120 Acellular normothermic ex vivo liver perfusion for donor liver preservation121 Pancreatic cancer and predictors of survival: comparing the CA 19–9/bilirubin ratio with the McGill Brisbane Scoring System122 Staged liver resections for bilobar hepatic colorectal metastases: a single centre experience123 Economic model of observation versus immediate resection of hepatic adenomas124 Resection of colorectal liver metastasis in the elderly125 Acceptable long-term survival in patients undergoing liver resection for metastases from noncolorectal, non-neuroendocrine, nonsarcoma malignancies126 Patient and clinicopathological features and prognosis of CK19+ hepatocellular carcinomas: a case–control study127 The management of blunt hepatic trauma in the age of angioembolization: a single centre experience128 Liver resections for noncolorectal and non-neuroendocrine metastases: an evaluation of oncologic outcomes129 Developing an evidence-based clinical pathway for patients undergoing pancreaticoduodenectomy130 Hepatitis C infection and hepatocellular carcinoma in liver transplant: a 20 year experience131 The effect of medication on the risk of post-ERCP pancreatitis132 Temporal trends in the use of diagnostic imaging for patients with hepato-pancreato-biliary (HPB) conditions: How much ionizing radiation are we really using?196 A phase II study of aggressive metastasectomy for intra-and extrahepatic metastases from colorectal cancer133 Why do women choose mastectomy for breast cancer treatment? A conceptual framework for understanding surgical decision-making in early-stage breast cancer134 Synoptic operative reporting: documentation of quality of care data for rectal cancer surgery135 Learning curve analysis for cytoreductive surgery: a useful application of the cumulative sum (CUSUM) method136 Pancreatic cancer is strongly associated with a unique urinary metabolomic signature137 Concurrent neoadjuvant chemo/radiation in locally advanced breast cancer138 Impact of positron emission tomography on clinical staging of newly diagnosed rectal cancer: a specialized single centre retrospective study139 An evaluation of intraoperative Faxitron microradiography versus conventional specimen radiography for the excision of nonpalpable breast lesions140 Comparison of breast cancer treatment wait-times in the Southern Interior of British Columbia in 2006 and 2010141 Factors affecting lymph nodes harvest in colorectal carcinoma142 Laparoscopic adrenalectomy for metastases143 You have a message! Social networking as a motivator for fundamentals of laparoscopic surgery (FLS) training144 The evaluation and validation of a rapid diagnostic and support clinic for women assessment for breast cancer145 Oncoplastic breast surgery: oncologic benefits and limitations146 A qualitative study on rectal cancer patients’ preferences for location of surgical care147 The effect of surgery on local recurrence in young women with breast cancer148 Elevated IL-6 and IL-8 levels in tumour microenvironment is not associated with increased serum levels in humans with Pseudomyxoma peritonei and peritoneal mesothelioma149 Conversion from laparoscopic to open approach during gastrectomy: a population-based analysis150 A scoping review of surgical process improvement tools (SPITs) in cancer surgery151 Splenectomy during gastric cancer surgery: a population-based study152 Defining the polo-like kinase 4 (Plk4) interactome in cancer cell protrusions153 Neoadjuvant imatinib mesylate for locally advanced gastrointestinal stromal tumours154 Implementing results from ACOSOG Z0011: Practice-changing or practice-affirming?155 Should lymph node retrieval be a surgical quality indicator in colon cancer?156 Long-term outcomes following resection of retroperitoneal recurrence of colorectal cancer157 Clinical research in surgical oncology: an analysis of clinicaltrials.gov158 Radiation therapy after breast conserving surgery: When are we missing the mark?159 The accuracy of endorectal ultrasound in staging rectal lesions in patients undergoing transanal endoscopic microsurgery160 Quality improvement in gastrointestinal cancer surgery: expert panel recommendations for priority research areas161 Factors influencing the quality of local management of ductal carcinoma in situ: a cohort study162 Papillary thyroid microcarcinoma: Does size matter?163 Hyperthermic isolated limb perfusion for extremity soft tissue sarcomas: systematic review of clinical efficacy and quality assessment of reported trials164 Adherence to antiestrogen therapy in seniors with breast cancer: How well are we doing?165 Parathyroid carcinoma: Challenging the surgical dogma?166 A qualitative assessment of the journey to delayed breast reconstruction195 The role of yoga therapy in breast cancer patients167 Outcomes reported in comparative studies of surgical interventions168 Enhanced recovery pathways decrease length of stay following colorectal surgery, but how quickly do patients actually recover?169 The impact of complications on bed utilization after elective colorectal resection170 Impact of trimodal prehabilitation program on functional recovery after colorectal cancer surgery: a pilot study171 Complex fistula-in-ano: Should the plug be abandoned in favour of the LIFT or BioLIFT?172 Prognostic utility of cyclooxygenase-2 expression by colon and rectal cancer173 Laparoscopic right hemicolectomy with complete mesocolic excision provides acceptable perioperative outcomes but is complex and time-consuming: analysis of learning curves for a novice minimally invasive surgeon174 Intraoperative quality assessment following double stapled circular colorectal anastomosis175 Improving patient outcomes through quality assessment of rectal cancer care176 Are physicians willing to accept a decrease in treatment effectiveness for improved functional outcomes for low rectal cancer?177 Turnbull-Cutait delayed coloanal anastomosis for the treatment of distal rectal cancer: a prospective cohort study178 Preoperative high-dose rate brachytherapy in preparation for sphincter preservation surgery for patients with advanced cancer of the lower rectum179 Impact of an enhanced recovery program on short-term outcomes after scheduled laparoscopic colon resection180 The clinical results of the Turnbull-Cutait delayed coloanal anastomosis: a systematic review181 Is a vertical rectus abdominus flap (VRAM) necessary? An analysis of perineal wound complications182 Fistula plug versus endorectal anal advancement flap for the treatment of high transsphincteric cryptoglandular anal fistulas: a systematic review and meta-analysis183 Maternal and neonatal outcomes following colorectal cancer surgery184 Transanal drainage to treat anastomotic leaks after low anterior resection for rectal cancer: a valuable option185 Trends in colon cancer in Ontario: 2002–2009186 Validation of electronically derived short-term outcomes in colorectal surgery187 A population-based assessment of transanal and endoscopic resection for adenocarcinoma of the rectum188 Laparoscopic colorectal surgery in the emergency setting: trends in the province of Ontario from 2002 to 2009189 Prevention of perineal hernia after laparoscopic and robotic abdominoperineal resection: review with case series of internal hernia through pelvic mesh which was placed in attempt to prevent perineal hernia190 Effect of rectal cancer treatments on quality of life191 The use of antibacterial sutures as an adjunctive preventative strategy for surgical site infection in Canada: an economic analysis192 Impact of socioeconomic status on colorectal cancer screening and stage at presentation: preliminary results of a population-based study from an urban Canadian centre193 Initial perioperative results of the first transanal endoscopic microsurgery (TEM) program in the province of Quebec194 Use of negative pressure wound therapy decreases perineal wound infections following abdominal perineal resection. Can J Surg 2012; 55:S63-S135. [DOI: 10.1503/cjs.016712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Spherical lens versus aspheric artificial cornea for intraocular lens testing. OPTICS LETTERS 2010; 35:1539-41. [PMID: 20479801 DOI: 10.1364/ol.35.001539] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Recent versions of the International Organization for Standardization (ISO)-based model eye for intraocular lens testing include an artificial cornea whose spherical aberration is chosen to match the value of a human cornea. Aspheric lenses have been used as artificial corneas, but they are expensive and difficult to manufacture. This Letter demonstrates that the aspheric lens can be advantageously replaced with a simple biconvex spherical lens of the same focal length and similar wavefront error. A linear dependence is shown between the Coddington shape factor of the spherical lens and the value of the induced spherical aberration. This relationship is used to match the wavefront error of the spherical lens to the one produced by the aspheric lens. A modified ISO model eye, containing this alternative spherical lens as the artificial cornea, is proposed for the on-axis optical assessment of intraocular lenses. Its suitability for off-axis testing is discussed.
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What are the highest priorities for research in prehospital care? Results of a review and consultation exercise. Arch Emerg Med 2009. [DOI: 10.1136/emj.2009.075416a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Reliability and validity of the Opiate Treatment Index among a sample of opioid users in the United Kingdom. Drug Alcohol Rev 2009; 15:261-70. [PMID: 16203381 DOI: 10.1080/09595239600186001] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
To validate the Opiate Treatment Index (OTI) for use in the United Kingdom, 72 subjects attending two methadone clinics in London completed confidential interviews with two researchers at two points in time, 1-2 weeks apart. About half the interviews were conducted by the same interviewer on both occasions, and the remaining by different interviewers. These research designs enabled an estimation of the test-retest and inter-rater reliability of the instrument. Subjects' responses were validated against key worker reports and self-reported drug use against urinalysis results. The majority of the respondents were males (65%) and their mean age was 34.2 years (range 21-52; SD 8.5). Test-retest reliability coefficients were high for all the scales (range 0.77-0.86) in both the same and different interviewer situations. The internal reliability of the scales was generally high (Cronbach's alpha: range 0.34-0.93). The correlation with key workers' reports was high with the percentage agreement on the items ranging 74-100 (mean 87). The percentage agreement of self-reported drug use with urinalysis results was high (range 69-95; mean 89). These findings are similar to those obtained among Australian subjects and suggest a high cross-cultural validity for the OTI. Minor changes to the OTI have been incorporated into a modified version for use in the UK.
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Documenting innovative pharmacy practice in Canada 2007. Can Pharm J (Ott) 2008. [DOI: 10.3821/1913-701x(2008)141[275:dippic]2.0.co;2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Abstract
The properties of an interacting electron system depend on the electron correlations and the effective dimensionality. For example, Coulomb repulsion between electrons may inhibit, or completely block, conduction by intersite electron hopping, thereby determining whether a material is a metal or an insulator. Furthermore, correlation effects increase as the number of effective dimensions decreases; in three-dimensional systems, the low-energy electronic states behave as quasiparticles, whereas in one-dimensional systems, even weak interactions break the quasiparticles into collective excitations. Dimensionality is particularly important for exotic low-dimensional materials where one- or two-dimensional building blocks are loosely connected into a three-dimensional whole. Here we examine two such layered metallic systems with angle-resolved photoemission spectroscopy and electronic transport measurements, and we find a crossover in the number of effective dimensions from two to three with decreasing temperature. This is apparent from the observation that, in the direction perpendicular to the layers, the materials have an insulating character at high temperatures but become metal-like at low temperatures, whereas transport within the layers remains metallic over the whole temperature range. We propose that this change in effective dimensionality correlates with the presence of coherent quasiparticles within the layers.
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Abstract
The primary walls of grasses are composed of cellulose microfibrils, glucuronoarabinoxylans (GAXs), and mixed-linkage beta-glucans, together with smaller amounts of xyloglucans, glucomannans, pectins, and a network of polyphenolic substances. Chemical imaging by Fourier transform infrared microspectroscopy revealed large differences in the distributions of many chemical species between different tissues of the maize (Zea mays) coleoptile. This was confirmed by chemical analyses of isolated outer epidermal tissues compared with mesophyll-enriched preparations. Glucomannans and esterified uronic acids were more abundant in the epidermis, whereas beta-glucans were more abundant in the mesophyll cells. The localization of beta-glucan was confirmed by immunocytochemistry in the electron microscope and quantitative biochemical assays. We used field emission scanning electron microscopy, infrared microspectroscopy, and biochemical characterization of sequentially extracted polymers to further characterize the cell wall architecture of the epidermis. Oxidation of the phenolic network followed by dilute NaOH extraction widened the pores of the wall substantially and permitted observation by scanning electron microscopy of up to six distinct microfibrillar lamellae. Sequential chemical extraction of specific polysaccharides together with enzymic digestion of beta-glucans allowed us to distinguish two distinct domains in the grass primary wall. First, a beta-glucan-enriched domain, coextensive with GAXs of low degrees of arabinosyl substitution and glucomannans, is tightly associated around microfibrils. Second, a GAX that is more highly substituted with arabinosyl residues and additional glucomannan provides an interstitial domain that interconnects the beta-glucan-coated microfibrils. Implications for current models that attempt to explain the biochemical and biophysical mechanism of wall loosening during cell growth are discussed.
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Cell wall architecture of the elongating maize coleoptile. PLANT PHYSIOLOGY 2001; 127:551-65. [PMID: 11598229 PMCID: PMC125090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 02/14/2001] [Revised: 04/12/2001] [Accepted: 06/15/2001] [Indexed: 03/16/2024]
Abstract
The primary walls of grasses are composed of cellulose microfibrils, glucuronoarabinoxylans (GAXs), and mixed-linkage beta-glucans, together with smaller amounts of xyloglucans, glucomannans, pectins, and a network of polyphenolic substances. Chemical imaging by Fourier transform infrared microspectroscopy revealed large differences in the distributions of many chemical species between different tissues of the maize (Zea mays) coleoptile. This was confirmed by chemical analyses of isolated outer epidermal tissues compared with mesophyll-enriched preparations. Glucomannans and esterified uronic acids were more abundant in the epidermis, whereas beta-glucans were more abundant in the mesophyll cells. The localization of beta-glucan was confirmed by immunocytochemistry in the electron microscope and quantitative biochemical assays. We used field emission scanning electron microscopy, infrared microspectroscopy, and biochemical characterization of sequentially extracted polymers to further characterize the cell wall architecture of the epidermis. Oxidation of the phenolic network followed by dilute NaOH extraction widened the pores of the wall substantially and permitted observation by scanning electron microscopy of up to six distinct microfibrillar lamellae. Sequential chemical extraction of specific polysaccharides together with enzymic digestion of beta-glucans allowed us to distinguish two distinct domains in the grass primary wall. First, a beta-glucan-enriched domain, coextensive with GAXs of low degrees of arabinosyl substitution and glucomannans, is tightly associated around microfibrils. Second, a GAX that is more highly substituted with arabinosyl residues and additional glucomannan provides an interstitial domain that interconnects the beta-glucan-coated microfibrils. Implications for current models that attempt to explain the biochemical and biophysical mechanism of wall loosening during cell growth are discussed.
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Single ribosomal transcription units are linear, compacted Christmas trees in plant nucleoli. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2001; 27:223-233. [PMID: 11532168 DOI: 10.1046/j.1365-313x.2001.01091.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The rDNA transcription units are enormous macromolecular structures located in the nucleolus and containing 50-100 RNA polymerases together with the nascent pre-rRNA attached to the rDNA. It has not previously been possible to visualize nucleolar transcription units directly in intact nucleoli, although highly spread preparations in the electron microscope have been imaged as "Christmas trees" 2-3 microm long. Here we determine the relative conformation of individual transcription units in Pisum sativum plant nucleoli using a novel labelling technique. Nascent transcripts were detected by a highly sensitive silver-enhanced 1 nm gold procedure, followed by 3D electron microscopy of entire nucleoli. Individual transcription units are seen as conical, elongated clusters approximately 300 nm in length and 130 nm in width at the thickest end. We further show that there were approximately 300 active ribosomal genes in the nucleoli examined. The underlying chromatin structure of the transcribing rDNA was directly visualized by applying a novel limited extraction procedure to fixed specimens in order to wash out the proteins and RNA, thus specifically revealing DNA strands after uranyl acetate staining. Using this technique, followed by post-embedding in situ hybridization, we observed that the nucleolar rDNA fibres are not extended but show a coiled, thread-like appearance. Our results show for the first time that native rDNA transcription units are linear, compacted Christmas trees.
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How many women lose bone mineral density while taking hormone replacement therapy? Results from the Postmenopausal Estrogen/Progestin Interventions Trial. ARCHIVES OF INTERNAL MEDICINE 2000; 160:3065-71. [PMID: 11074735 DOI: 10.1001/archinte.160.20.3065] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND The frequency of bone loss among women using postmenopausal hormone therapy is unknown. METHODS We used data from the Postmenopausal Estrogen/Progestin Interventions Trial to address the frequency of bone loss among women using postmenopausal hormone replacement therapy. Of 701 women randomized to active treatment (conjugated equine estrogens alone or in combination with 1 of 3 progestins), 538 (76.7%) were adherent and had replicate bone mineral density (BMD) measures at baseline, 12 months, and 36 months. Of 174 placebo-assigned women, 132 (75.9%) were similarly eligible. Replicate BMD measures were used to calculate within-person measurement errors, which were then used to delineate cut points that defined bone losers with 97.5%, 95.0%, 90.0%, or 75.0% confidence. RESULTS At the lumbar spine, during the first 12 months, 1.5% of hormone users lost BMD with 97.5% confidence, corresponding to a decline of -3% per year; during months 12 to 36, only 0.6% of treated women lost spinal BMD to this degree. An annual loss of -1% or more was the criterion for spinal bone loss at the 75.0% confidence level; 5.1% and 8.0% of hormone users met this criterion in the first year and in months 12 to 36, respectively. For the total hip, during the first 12 months, 2.3% of hormone-adherent women lost -3.0% per year or more, the 97.5% confidence definition of loss; 0.4% were so classified during months 12 to 36. To be 75.0% confident of hip BMD loss, a -1.0% per year decline in BMD was required; using this criterion, 14.5% and 11.8% of hormone users lost total hip BMD between 0 to 12 and 12 to 36 months, respectively. Among hormone-adherent women, at the spine and hip, there was virtually no overlap between women classified as bone losers in the first 12 months and those classified as such in the last 24 months. With 95.0% certainty, corresponding to an approximate loss of -2.5% at the spine and hip, 31.3% and 11.7% of placebo-adherent women lost spinal BMD in the first 12 and last 24 months, respectively. Parallel figures for the hip were 32.3% and 7.9%, respectively. CONCLUSION Bone loss while taking postmenopausal hormones is rare, and bone loss among untreated women is far from universal.
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Abstract
The complexes [Na(CTV)2(OH)(H2O)](H2O)(DMF)2(o-carborane) (3; CTV = cyclotriveratrylene), [K(OH)(CTV)(DMF)]2(o-carborane) (4), [(DMF)(CTV)]2(H2O)4(o-carborane) (5), and (o-carborane)(CTV)(DMF)2 (6) all form as crystalline inclusion complexes from N,N'-dimethylformamide (DMF) solution. Complexes 3 and 4 are the first reported examples of CTV acting as a chelating ligand, with two CTV molecules coordinating cis to the six-coordinate M+ centers (M=Na, K). The extended structures of complexes 3-5 are similar, forming extended coordinate and/or hydrogen-bonding interactions and all feature intracavity complexation of DMF by CTV, while the complex 6 forms an assembly of (o-carborane) intersection of two sets (CTV) ball-and-socket supermolecules with DMF as a channel-type included guest.
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A glucoamylase::GFP gene fusion to study protein secretion by individual hyphae of Aspergillus niger. J Microbiol Methods 2000; 42:39-48. [PMID: 11000429 DOI: 10.1016/s0167-7012(00)00170-6] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Although Aspergillus niger is used as a host for heterologous protein production, yields are generally lower than those obtained for homologous proteins. Mechanisms of protein secretion and the secretory pathway in filamentous fungi are poorly characterised, although there is evidence to suggest that secretion occurs by a mechanism similar to that in other eukaryotes, but with proteins destined for secretion being directed to the hyphal tip. We report on a method using a glucoamylase: GFP gene fusion which allows us for the first time to monitor, in vivo, protein secretion in A. niger at the single hyphal level. A synthetic green fluorescent protein (sGFP(S65T)) was fused to truncated A. niger glucoamylase (GLA:499). Southern blot analysis of transformants confirmed that the gene fusion had successfully integrated into the A. niger genome. Confocal and fluorescence microscopy revealed that the GLA::GFP fusion protein is fluorescent in A. niger and appears to be directed to the hyphal tip. In young mycelia, hyphal cell wall fluorescence is apparent and immunogold labelling of GFP confirmed that GFP was partially localised within the hyphal cell wall. Using Western blotting, extracellular GLA::GFP was detected only in culture filtrates of young mycelia grown in a soya milk medium. The actin inhibitor latrunculin B was used to disrupt the secretion process, and its effects on the distribution of GLA::GFP were monitored.
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Personal and situational variables that describe coping with acute stress in competitive sport. THE JOURNAL OF SOCIAL PSYCHOLOGY 2000; 140:434-50. [PMID: 10981373 DOI: 10.1080/00224540009600483] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The authors examined the degree to which competitive basketball players in Australia were consistent in their cognitive appraisals and coping strategies in response to 4 types of stressful situations that they had experienced during previous basketball games as functions of perceived stress intensity. The authors predicted that both approach and avoidance coping strategies would be dependent on the type of stressful event, in accord with the transactional model. The results supported that prediction: Approach strategies were more prevalent than avoidance strategies following 3 of the 4 events. Cognitive appraisals and perceived stress intensity also strongly influenced the participants' use of coping strategies, accounting for 34% of the variance.
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Abstract
Localised alterations in cytoplasmic Ca(2+) levels are an integral part of the response of eukaryotic cells to a plethora of external stimuli. Due to the large size of nuclear pores, it has generally been assumed that intranuclear Ca(2+) levels reflect the prevailing cytoplasmic Ca(2+) levels. Using nuclei prepared from carrot (Daucus carota L.) cells, we now show that Ca(2+) can be transported across nuclear membranes in an ATP-dependent manner and that over 95% of Ca(2+) is accumulated into a pool releasable by the Ca(2+) ionophore A.23187. ATP-dependent nuclear Ca(2+) uptake did not occur in the presence of ADP or ADPgammaS and was abolished by orthovanadate. Confocal microscopy of nuclei loaded with dextran-linked Indo-1 showed that the initial ATP-induced rise in [Ca(2+)] occurs in the nuclear periphery. The occurrence of ATP-dependent Ca(2+) uptake in plant nuclei suggests that alterations of intranuclear Ca(2+) levels may occur independently of cytoplasmic [Ca(2+)] changes.
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Abstract
A neglected aspect of intonation research has been the nature and extent of variability in the use of prosodic features within a speech community. Cross-speaker variability in intonation was investigated through analysis of data collected from 90 adult speakers of English from London, England, using a new prosodic test battery (PEPS). PEPS is designed to elicit information about how speakers use prosodic features to realize different types of linguistic and communicative function in their own speech, and also how they perceive and interpret these features. Although there were no significant effects of gender or age in isolation on prosodic performance, there was a small effect of educational level among younger adults. Despite this group homogeneity, qualitative analysis of data from two of the production tasks showed considerable variation across participants in their use of prosodic features, suggesting that speakers' realization of communicative functions through prosody is more variable than has hitherto been assumed.
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Abstract
The nucleus in plants and animals is a highly structured organelle containing several well-defined subregions or suborganelles. These include the nucleolus, interphase chromosome territories and coiled bodies. We have visualized transcription sites in plants at both light- and electron-microscopy level by the incorporation of BrUTP. In the nucleolus many dispersed foci are revealed within the dense fibrillar component, each of which probably corresponds to a single gene copy. In the nucleoplasm there are also many dispersed foci of transcription, but not enough to correspond to one site per transcribed gene. We have shown that in wheat, and probably many other plant species, interphase chromosome territories are organized in a very regular way, with all the chromosomes in the Rabl configuration, all the centromeres clustered at the nuclear membrane and all the telomeres located at the nuclear membrane on the opposite side of the nucleus. However, despite this regular, polarized structure, there is no sign of polarization of transcription sites, or of any preferred location for them with respect to chromosome territorial boundaries. The nucleus is also highly dynamic. As an example, we have shown by the use of a green fluorescent protein fusion to the spliceosomal protein U2B" that coiled bodies move and coalesce within the nucleus, and may act as transport structures within the nucleus and nucleolus.
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Nucleoside analogs plus ritonavir in stable antiretroviral therapy-experienced HIV-infected children: a randomized controlled trial. Pediatric AIDS Clinical Trials Group 338 Study Team. JAMA 2000; 283:492-8. [PMID: 10659875 DOI: 10.1001/jama.283.4.492] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CONTEXT Although protease inhibitors are used routinely in adults with human immunodeficiency virus (HIV) infection, the role of these drugs in the treatment of clinically stable HIV-infected children is not clear. OBJECTIVE To evaluate the safety, tolerance, and virologic response produced by a change in antiretroviral therapy in HIV-infected children who were clinically and immunologically stable while receiving previous therapy. DESIGN The Pediatric AIDS Clinical Trials Group 338, a multicenter, phase 2, randomized, open-label controlled trial conducted from February 6 to April 30, 1997 (patient entry period); patients were followed up for 48 weeks. SETTING Pediatric HIV research clinics in the United States and Puerto Rico. PATIENTS Two hundred ninety-seven antiretroviral-experienced, protease inhibitor-naive, clinically stable HIV-infected children aged 2 to 17 years. INTERVENTIONS Children were randomized to receive zidovudine, 160 mg/m2 3 times per day, plus lamivudine, 4 mg/kg 2 times per day (n = 100); the same regimen plus ritonavir, 350 mg/m2 2 times per day (n = 100); or ritonavir, 350 mg/m2 2 times per day, and stavudine, 4 mg/kg 2 times per day (n = 97). MAIN OUTCOME MEASURE Plasma HIV-1 RNA levels at study weeks 12 and 48, compared among the 3 treatment groups. RESULTS At study week 12, 12% of patients in the zidovudine-lamivudine group had undetectable plasma HIV RNA levels (<400 copies/mL) compared with 52% and 54% of patients in the 2- and 3-drug ritonavir-containing groups, respectively (P<.001). Through study week 48, 70% of children continued receiving their ritonavir-containing regimen. At study week 48, 42% of children receiving ritonavir plus 2 nucleosides compared with 27% of those receiving ritonavir and a single nucleoside had undetectable HIV RNA levels (P = .04); however, similar proportions in each group continuing initial therapy had HIV RNA levels of less than 10000 copies/mL (58% vs 48%, respectively; P = .19). CONCLUSIONS In our study, change in antiretroviral therapy to a ritonavir-containing regimen was associated with superior virologic response at study week 12 compared with change to a dual nucleoside analog regimen. More children receiving ritonavir in combination with 2 compared with 1 nucleoside analog had undetectable HIV RNA levels at study week 48.
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The relationship of biochemical markers of bone turnover to bone density changes in postmenopausal women: results from the Postmenopausal Estrogen/Progestin Interventions (PEPI) trial. J Bone Miner Res 1999; 14:1583-95. [PMID: 10469288 DOI: 10.1359/jbmr.1999.14.9.1583] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We assessed the associations of eight bone turnover markers (BTMs) with baseline and 1-year percentage changes in lumbar spine and hip bone mineral density (BMD) of 293 postmenopausal women undergoing treatment with hormone replacement therapy (HRT) or placebo using squared correlation coefficients (R2). In 239 women assigned to treatment with estrogen alone or with with estrogen plus progestins (active treatment), mean percentage changes for all markers decreased significantly and remained below baseline values through 3 years of study, whereas mean percentage changes for 54 women assigned to the placebo group showed no significant change from baseline in any marker. At baseline, age and body mass index (BMI) together accounted for 16% and 25% of the variance in spine and hip BMD, respectively. The telopeptide resorption marker, cross-linked N-telopeptide of type I collagen (NTX), alone accounted for 12% and 8% of variance, respectively. Another telopeptide, carboxy-terminal telopeptide of type I collagen (Crosslaps), accounted for 8% and 7% of variance, respectively. A bone-specific alkaline phosphatase (BALP-2) accounted for 8% of variance at the spine and 5% at the hip. No other marker accounted for more than 5% of total variance at either site; adding either baseline NTX, Crosslaps, or BAP-2 to regressions containing age and BMI increased R2 values at the spine and hip to about 22% and 28%, respectively. In the placebo group, baseline spine BMD accounted for 4% of the variance in 1-year spine BMD percentage change, whereas baseline values for age and BMI accounted for 1% and 0% of the variance, respectively; none of the three accounted for more than 0% of hip BMD percentage change; Crosslaps and NTX contributed 5% and 4% to the variance in 1-year spine BMD percentage change, but other markers accounted for < 2% of variance at the spine. At the hip, another BALP (BALP-1) accounted for 4% of variance, but no other baseline marker except NTX accounted for more than 1% of variance. In the active treatment group, baseline values for age, BMI, and spine BMD together accounted for 13% of the percentage change in spine BMD and for 4% of the BMD change at the hip. No individual or pair of baseline markers significantly enhanced these R2 values, but addition of 1-year percentage changes in some individual markers did significantly increase it. The largest R2 value was obtained by adding the percentage change in BALP-2, which increased the R2 in spine BMD percentage change to 20% and that at the hip to 8%. Adding baseline and change variables for all eight markers to the regression increased R2 to 28% at the spine and 12% at the hip. Restricting the set of analyses to individuals who suppressed marker activity beyond the precision error for the measurement did not improve R2s for the regressions. When baseline marker values were stratified into quartiles, only NTX and osteocalcin showed significant relationships between quartile and change in spine BMD, and these did not reach significance at the hip. When the 1-year change in markers was stratified into quartiles, significant relationships with percentage change in spine BMD were observed only for BALP phosphatases. We conclude that BTMs are not a surrogate for BMD to identify women with low bone mass and that they offer little useful information for predicting BMD changes for individual untreated or HRT-treated postmenopausal women.
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Ribavirin and interferon alfa-2b in chronic hepatitis C: assessment of possible pharmacokinetic and pharmacodynamic interactions. Br J Clin Pharmacol 1998; 46:563-70. [PMID: 9862245 PMCID: PMC1873804 DOI: 10.1046/j.1365-2125.1998.00836.x] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
AIMS The primary objective of this study was to determine whether pharmacokinetic interactions occurred between interferon alpha-2b (IFN) and ribavirin in patients with chronic hepatitis C infections. Additionally this study assessed the single and multiple-dose pharmacokinetics of ribavirin and IFN, and compared the safety, tolerability and antiviral pharmacodynamics of IFN plus ribavirin compared with either drug alone. METHODS In this open label parallel group study, patients with chronic hepatitis C were randomized to receive IFN 3 million IU thrice weekly s.c. alone, ribavirin 600 mg twice daily p.o. alone or both drugs in combination over 6 weeks. Single and multiple dose pharmacokinetics and indices of antiviral pharmacodynamics were assessed during weeks 1 and 6, along with safety assessments during the study. RESULTS The range of mean ribavirin terminal phase half-lives after single doses was 44-49 h. Comparison of week 1 and week 6 AUC(0,12h) values showed accumulation in plasma of approximately 6-fold. The range of mean washout half-lives after week 6 was 274-298 h, reflecting release of ribavirin from deep compartment stores. The range of single and multiple dose IFN terminal phase half-lives was 5-7 h. IFN demonstrated an increase in bioavailability (approximately 2-fold) upon multiple dose administration. Ribavirin and IFN pharmacokinetic parameters for combined ribavirin and IFN were similar to those during monotherapy with either compound, although the power of this study to detect differences was low. Serum HCV-RNA titers and ALT concentrations were reduced by IFN alone, ribavirin alone reduced ALT concentrations only, and combined IFN plus ribavirin produced numerically greater falls in both measurements than either treatment alone. Serum concentrations of neopterin and activity of 2',5'-oligoadenylate synthetase (2'5'-OAS) were increased by IFN alone and in combination with ribavirin, whereas serum 2'5'-OAS activity was decreased and neopterin concentrations unaltered by ribavirin monotherapy. IFN and ribavirin monotherapy produced characteristic changes in safety laboratory tests (IFN--reductions in white cells, neutrophils and platelets; ribavirin--reduced haemoglobin) and characteristic adverse event profiles (IFN--headache, flu-like symptoms, fatigue, anorexia, nausea, myalgia, and insomnia; ribavirin--headache, fatigue, myalgia, and pruritus). There was no additive effect of combination therapy on safety laboratory tests or reported adverse events. All changes were fully reversible upon treatment cessation. CONCLUSIONS There was no evidence of pharmacokinetic interactions between IFN and ribavirin in this study. There were numerical trends indicating that the combination of IFN and ribavirin reduced titers of HCV-RNA to a greater extent than did either treatment alone, and the safety profile of combination therapy was similar to those of both monotherapy treatments.
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Prosody as an interactional resource: turn-projection and overlap. LANGUAGE AND SPEECH 1998; 41 ( Pt 3-4):265-294. [PMID: 10746359 DOI: 10.1177/002383099804100403] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
One aim of current research into talk-in-interaction is to identify the resources that enable recipients to monitor the course of a turn in progress in order to project its upcoming completion. This issue is addressed through analysis of instances of overlapping talk, focusing on their design--that is, their particular prosodic and other linguistic characteristics; their placement--in other words, where precisely they occur in relation to the turn being overlapped; and the subsequent behavior of the coparticipants. Phonetic analysis is combined with interactional techniques developed within Conversation Analysis, to warrant the relevance of categories by reference to the behavior of the participants themselves. As French and Local (1983) found, for an incoming to be treated as turn-competitive, it has to be designed with relatively high pitch and loud volume. These turn-competitive incomings are positioned within the turn in progress, and before the final major accent. By contrast, overlapping incomings positioned after the major accent are not designed as or treated as turn-competitive. On the basis of this analysis, we can define transition relevance place (TRP) as the space between the TRP-projecting accent of the current turn and the onset of the next turn. TRP-projecting accents are identifiable on independent grounds, being phonetically distinct from non-TRP-projecting accents. They thus provide a robust resource for participants to monitor the upcoming completion of the turn.
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Abstract
The epidermis of Arabidopsis wild-type primary roots, in which some cells grow hairs and others remain hairless in a position-dependent manner, has become an established model system to study cell differentiation. Here we present a molecular analysis of the RHL1 (ROOT HAIRLESS 1) gene that, if mutated, prevents the formation of hairs on primary roots and causes a seedling lethal phenotype. We have cloned the RHL1 gene by use of a T-DNA-tagged mutant and found that it encodes a protein that appears to be plant specific. The predicted RHL1 gene product is a small hydrophilic protein (38.9 kD) containing putative nuclear localization signals and shows no significant homology to any known amino acid sequence. We demonstrate that a 78-amino-acid sequence at its amino terminus is capable of directing an RHL1-GFP fusion protein to the nucleus. The RHL1 transcript is present throughout the wild-type plant and in suspension culture cells, but in very low amounts, suggesting a regulatory function for the RHL1 protein. Structural evidence suggests a role for the RHL1 gene product in the nucleolus. We have examined the genetic relationship between RHL1 and GL2, an inhibitor of root hair initiation in non-hair cells. Our molecular and genetic data with double mutants, together with the expression analysis of a GL2 promoter-GUS reporter gene construct, indicate that the RHL1 gene acts independently of GL2.
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Feasibility of prescribing injectable heroin and methadone to opiate-dependent drug users: associated health gains and harm reductions. Med J Aust 1998; 168:596-600. [PMID: 9673620 DOI: 10.5694/j.1326-5377.1998.tb141444.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVE To assess the feasibility of offering the choice of prescribing injectable heroin (diamorphine) or injectable methadone to opiate-dependent injecting drug users and to assess whether there are health and social gains associated with prescribing injectable opiates. DESIGN A protocol-driven prospective observational study. Type of injectable opiate received was based on self-selection. SETTING A large west London drug clinic. PATIENTS Fifty-eight patients admitted to the clinic between 1 June 1995 and 31 December 1996, who were long term opiate-dependent injecting drug users, who had previously tried and failed oral methadone and who were apparently unable or unwilling to give up injecting. MAIN OUTCOME MEASURES Retention in treatment, illicit drug use, HIV risk behaviour, criminal activity, social functioning, health and psychological status as measured by self-report, urinalysis and doctor's ratings. RESULTS Thirty-seven patients (64%) chose heroin and 21 (36%) chose injectable methadone. Fifty (86%) were retained in treatment after three months, 40 (69%) after six months and 33 (57%) after 12 months. Among those in treatment at three months, there were significant reductions in illicit drug use, illicit drug-injecting risk behaviour, and criminal activity, and significant improvements in social functioning, health status and psychological adjustment. Generally, these gains were sustained between three, six and 12 months. Doctors' ratings of health and urinalysis results further supported these findings. CONCLUSIONS Injectable heroin is not always the drug of choice. This intervention retained most patients in treatment with substantial benefits to both patients and the community. Prescribing injectable opiates to long term injecting drug users is a feasible treatment option.
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Children's comprehension of unfamiliar regional accents: a preliminary investigation. JOURNAL OF CHILD LANGUAGE 1998; 25:343-365. [PMID: 9770911 DOI: 10.1017/s0305000998003444] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The effect of regional accent on children's processing of speech is a theoretically and practically important aspect of phonological development that has been little researched. 48 children from London, aged four and seven years old, were tested on their ability to repeat and define single words presented in their own accent and in a Glaswegian accent. Results showed that word comprehension was significantly reduced in the Glaswegian condition and that four-year-olds performed less successfully than seven-year-olds. Both groups made similar numbers of lexical misidentifications, but the younger children were more likely to fail to access any word at all. On the repetition task, the younger children showed a different pattern of errors to the older children, their productions being apparently more influenced by the phonetics of the Glaswegian stimuli. It is suggested that such phonetic responses are related to the younger children's failure to map the unfamiliar accent onto their own phonological representations. It is proposed that the lexical misidentifications, common to both age groups, are more likely to be induced by lack of context. The paper concludes with discussion of implications of these findings for our understanding of how children develop the ability to process unfamiliar regional accents.
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Missed problems and missed opportunities for addicted doctors. BMJ (CLINICAL RESEARCH ED.) 1998; 316:405-6. [PMID: 9492650 PMCID: PMC2665618 DOI: 10.1136/bmj.316.7129.405] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Taking charge of your practice. NURSING BC 1998; 30:16-7. [PMID: 10095564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Plant-adapted green fluorescent protein is a versatile vital reporter for gene expression, protein localization and mitosis in the filamentous fungus, Aspergillus nidulans. Mol Microbiol 1998; 27:121-30. [PMID: 9466261 DOI: 10.1046/j.1365-2958.1998.00664.x] [Citation(s) in RCA: 158] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Green fluorescent protein (GFP) is a useful reporter to follow the in vivo behaviour of proteins, but the wild-type gfp gene does not function in many organisms, including many plants and filamentous fungi. We show that codon-modified forms of gfp, produced for use in plants, function effectively in Aspergillus nidulans both as gene expression reporters and as vital reporters for protein location. To demonstrate the use of these modified gfps as reporter genes we have used fluorescence to follow ethanol-induced GFP expression from the alcA promoter. Translational fusions with the modified gfp were used to follow protein location in living cells; plant ER-retention signals targeted GFP to the endoplasmic reticulum, whereas fusion to the GAL4 DNA-binding domain targeted it to the nucleus. Nuclear-targeted GFP allowed real-time observation of nuclear movement and division. These modified gfp genes should provide useful markers to follow gene expression, organelle behaviour and protein trafficking in real time.
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Sites of rDNA transcription are widely dispersed through the nucleolus in Pisum sativum and can comprise single genes. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 1997; 12:571-81. [PMID: 9351243 DOI: 10.1046/j.1365-313x.1997.00571.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Incorporation by RNA polymerases of BrUTP into both plant root tissue and isolated plant nuclei as a method for localization of the sites of transcription has been used. In this paper pea root tissue was used, and under the conditions employed, nearly all the incorporation occurs in the nucleolus, and thus must be catalysed by RNA polymerase I. Immunofluorescence and confocal microscopy shows that incorporation occurs in a pattern consisting of many small foci distributed widely through the dense fibrillar component of the nucleoli. Immunogold labelling using silver-enhanced Nanogold probe at the electron microscopic level confirms the sites of transcription as small foci approximately 200 nm in diameter. Simultaneous fluorescence in situ hybridization with a probe to the external transcribed spacer (ETS) region of the pre-rRNA shows that the structures revealed by this probe and the BrUTP immunofluorescence labelling are very similar. A probe to the transcribed portion of the rDNA (18S) also shows a good correlation to the sites of BrUTP incorporation within the nucleolus. On the other hand a probe to the non-transcribed intergenic spacer region (NTS) shows very little coincidence with the sites of BrUTP incorporation, and double fluorescence in situ labelling with both 18S and NTS probes confirms this difference in localization. These results suggest that most BrUTP foci correspond to single transcribed genes.
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Structural and genetic analysis of epidermal cell differentiation in Arabidopsis primary roots. Development 1997; 124:1789-98. [PMID: 9165126 DOI: 10.1242/dev.124.9.1789] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In a screen designed to identify genes in the specification of epidermal cell fate in Arabidopsis primary roots we have isolated 8 new mutants that fall into 6 complementation groups corresponding to the ‘root hairless’ genes RHL1, RHL2 and RHL3 and the ‘ectopic root hair’ genes ERH1, ERH2 and ERH3. The erh2 mutant is allelic to pom1, a conditional root expansion mutant, and reveals a possible link between epidermal root hair initiation and radial cell expansion. Apart from erh1 the mutants also show defects in shoot development, indicating a complex role for the affected genes. Mutant phenotypes in the patterning and shape of leaf trichomes in rhl1, rhl2, rhl3 and erh3 were particularly obvious. The root hairless mutants are only partly responsive to increased ethylene concentrations, while the ectopic root hair mutants are fully responsive to reduced concentrations of ethylene, a permissive regulator of root hair initiation. This result and the analysis of double mutants suggest a complex pathway leading to root hair initiation that requires the RHL and ERH genes for correct differentiation.
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Abstract
Examines ethics in the health care industry from the perspectives of investors, employees, patients, competitors and the environment. Ethical behaviour in the health care industry is essential and desirable; however, determining which behavioural actions are ethical and which are unethical is difficult. Although never will everyone agree on specific ethical standards, everyone should agree that setting ethical standards is vital. Therefore, administrators of health care institutions and health care providers should work together to establish codes of ethics which define boundaries for ethical behaviours in the health care industry.
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Methods of and attitudes toward screening obstetrics and gynecology patients for domestic violence. Am J Obstet Gynecol 1995; 173:381-6; discussion 386-7. [PMID: 7645612 DOI: 10.1016/0002-9378(95)90256-2] [Citation(s) in RCA: 125] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE Our purpose was to define screening behaviors of obstetrician-gynecologists and barriers to screening their patients for domestic violence. STUDY DESIGN A questionnaire was developed to collect information on current practices and attitudes regarding screening for domestic violence. A randomly selected sample of obstetrician-gynecologists was surveyed. Respondents were also asked to rank a series of 19 potential barriers that may affect screening. RESULTS Of 6568 physicians sampled, 962 (14.6%) returned questionnaires. Of the respondents, 77.6% were male and 22.4% were female. Male physicians were less likely to screen for domestic violence (25.9% vs. 18.9%). Thirty-four percent said that they had no training in abuse. Physicians indicating they had received training in abuse were more likely to screen for domestic violence. The lack of education was identified as the most common barrier physicians have to screening. The feeling that abuse was not a problem in their patients (46%), lack of time to deal with abuse (39.2%), and frustration that the physician cannot help the victim (34.2%) were other common barriers. CONCLUSION The majority of obstetrician-gynecologists do not screen their patients for current or past domestic violence. If universal screening is to become a reality, educational tools and training materials are needed to overcome physician barriers.
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Chemical compatibility of inotropic and vasoactive agents delivered via a multiple line infusion system. Crit Care Med 1995; 23:1061-6. [PMID: 7774217 DOI: 10.1097/00003246-199506000-00011] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
OBJECTIVES To determine the chemical compatibility of three different triple drug admixtures diluted with either 5% dextrose in water or 0.9% NaCl solution when administered via a multiple line infusion system (Omni-Flow 4000, Abbott Laboratories, Abbott Park, IL). The triple drug admixtures were: a) dobutamine, dopamine, and norepinephrine; b) nitroglycerin, sodium nitroprusside, and dobutamine; and c) nitroglycerin, dopamine, and dobutamine. DESIGN Two phase in vitro compatibility study. SETTING Pharmaceutical laboratory. SUBJECTS None. INTERVENTIONS Phase I assessed chemical stability when the triple drug admixture was placed in a single container. In phase II, individual drug components of the admixtures were infused via the multiple line infusion system. Samples were collected at time 0, 1 hr, 2 hrs, 4 hrs, 12 hrs, and 24 hrs. All samples were frozen and stored at -70 degrees C until assayed. MEASUREMENTS AND MAIN RESULTS Samples were assayed using stability-indicating high performance liquid chromatography. The triple drug admixtures were considered to be chemically stable if there was < or = 10% loss of stated potency over 24 hrs. In phase I, chemical stability was observed for all triple drug admixtures at 24 hrs. In phase II, dobutamine, dopamine, norepinephrine, and sodium nitroprusside showed chemical stability at 24 hrs. Nitroglycerin showed a two-fold increase in concentration at 24 hrs compared with the initial concentration through the test infusion system; however, this amount was still one third lower than originally anticipated. CONCLUSIONS All triple drug admixtures were chemically stable when placed in single containers. Dobutamine, norepinephrine, and sodium nitroprusside showed chemical stability when delivered via a multiple line infusion system. The reduced recovery of nitroglycerin from the test infusion system may result from adsorption of the nitroglycerin to the polyvinyl chloride plastic cassette and tubing during infusion.
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Abstract
A procedure is described for obtaining clean maize cell wall preparations that contain embedded plasmodesmata. Negative staining and rotary shadowing have been used with transmission electron microscopy to visualise the plasmodesmata in these isolated walls, and to assess the effects of simple biochemical treatments on plasmodesmal components. Light protease treatment removes material from the exposed ends of plasmodesmata but does not extract the plasmodesmal core, which lies within the cell wall. However, heavy proteolysis occasionally removes the complete plasmodesma, including its enclosing collar structure, from the wall. Extraction with urea has a similar effect. The collar itself appears not to be proteinaceous in composition, although protein may bind it into the wall. Callose is localised in the wall around plasmodesmata, but does not appear to be a constituent of the collar. The membrane components of the plasmodesma (plasma membrane and desmotubule) can be extracted with membrane-solubilising detergents. This treatment releases from the wall a small number of proteins that are regarded as being potentially of plasmodesmal origin. These results show that plasmodesmata from maize can be dissected biochemically and suggest a strategy for the characterisation of individual molecular components.
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Vanadium air pollution: a cause of malabsorption and immunosuppression in cattle. Onderstepoort J Vet Res 1994; 61:303-16. [PMID: 7501362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
An epidemiological investigation into an "illthrift" problem occurring on a dairy farm adjacent to an alloy-processing unit, established that the probable cause of the problem was chronic vanadium poisoning. The disease manifested initially in animals 4-18 months old which showed emaciation, chronic diarrhoea and, in some cases, rhinitis, conjunctivitis and recumbency followed by death. Post-mortem (n = 17) and clinical-pathology findings (n = 60) indicated that malabsorption and immunosuppression were the basis of the pathogenesis in affected animals. Eight months after the commencement of the investigation, adult cows began showing evidence of emaciation, reduced milk production and an apparent increase in the number of abortions, stillbirths and dystocias. Over a 2-year period, 134 surface-soil samples, 134 subsoil samples and 134 grass samples from the farm were analysed for various fractions of vanadium. Thirty-four of each of these samples were collected at different time intervals (autumn 1990, summer 1991 and winter 1991) and at varying distances and directions from the processing unit, in order to gauge the magnitude of the problem, and the distribution pattern of vanadium, and to identify possible seasonal trends. The remaining 100 of each of these samples were taken at 100-m intervals over an area of approximately 1,140,000 m2 directly adjacent to the processing unit so that concentration isolines for vanadium could be drawn and the source more conclusively identified. The levels of vanadium were found to be highest closest to the mine, and surface-soil levels were consistently higher than subsoil levels, suggesting aerial pollution, which was confirmed by air sampling.(ABSTRACT TRUNCATED AT 250 WORDS)
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Abstract
We assessed the cross-sectional relationship of age, menopausal years, body mass, previous estrogen use, and ethnic background to bone mineral status in a sample of 875 healthy postmenopausal women at the time they were recruited from the community to participate in a multicenter clinical trial. The women were 1-10 years postmenopause, 45-64 years of age, and had not received estrogen replacement therapy within 3 months of enrollment. Of the participants, 89% were white, 69% had a spontaneous menopause, and 53% had a history of previous estrogen replacement therapy. Bone mineral density (BMD) of the lumbar spine (L2-4) and proximal femur was measured by dual-energy x-ray absorptiometry. Results were consistent with a significant negative linear regression of BMD on age or years from menopause. Body mass index (BMI) correlated significantly with BMD at all sites (L 2-4 r = 0.28; femoral neck r = 0.34, p < 0.0001). BMD adjusted for age and BMI were higher at both sites in women who had taken estrogen versus those who had not (L2-4 0.976 +/- 0.009 versus 0.932 +/- 0.01; femoral neck 0.740 +/- 0.006 versus 0.708 +/- 0.008, p < 0.05). Adjusted BMD also increased with duration of ERT. Parity was negatively associated with L2-4 BMD (p = 0.03) but did not correlate significantly with BMD at the femoral neck. Black women had the highest L2-4 BMD, and Hispanic women had the highest femoral neck BMD, even when results were adjusted for age and BMI. When data were corrected for differences in bone size, these interethnic differences were no longer significant. We conclude that increased body mass is positively correlated with BMD, and this may confer a degree of skeletal protection to heavier postmenopausal women. Exposure for 5 years to exogenous estrogen is associated with significantly increased age- and BMI-adjusted BMD.
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