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Prognostic value of FFRCT in patients with stable chest pain – a 3-year follow-up of the ADVANCE-DK registry. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehac544.202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Introduction
The short-term safety of using coronary CT angiography (CTA) derived fractional flow reserve (FFRCT) to guide downstream testing after CTA is well documented. Whether the prognostic information provided by FFRCT can be extended to sustained follow-up and to patients with a high degree of coronary artery calcification (CAC) is unknown.
Purpose
To evaluate the association between FFRCT and clinical outcomes in new onset stable symptomatic patients with coronary stenosis up to 3 years after CTA index testing.
Methods
Multicenter 3-year follow-up study of 900 patients from the Assessing Diagnostic Value of Non-invasive FFRCT in Coronary Care (ADVANCE) registry at three Danish sites, the “ADVANCE-DK Registry”. All patients had at least one ≥30% coronary stenosis by CTA and underwent subsequent core laboratory FFRCT analysis by HeartFlow. The criterium for an abnormal FFRCT test result was an FFRCT value ≤0.80 (2 cm distal to stenosis). High CAC was defined as a CAC score ≥400. The primary endpoint (PE) was a composite of all-cause death and spontaneous myocardial infarction (MI). The secondary endpoint (SE) was a composite of cardiovascular (CV) death and spontaneous MI. Events were adjudicated by an independent clinical committee.
Results
Patient characteristics are given in Table 1. Coronary stenosis ≥50% was present in 750 (83%) patients. In total 36 patients suffered a PE (all-cause death, n=24; MI, n=12) and 22 an SE (CV death, n=10; MI, n=12). An abnormal vs a normal FFRCT test result was associated with an increased risk of the PE and of the SE both overall and in patients with high CAC; PE (all), 6.6% vs 2.1%, relative risk (RR): 3.1; 95% CI: 1.6–6.3, p<0.001, SE (all), 5.0% vs 0.6%, RR: 8.7; 95% CI: non assessable, p<0.001, PE (high CAC), 9.0% vs 2.2%, RR: 4.1; 85% CI: 1.4–11.8, p=0.001, and SE (high CAC), 6.6% vs 0.5%, RR: 12.0; 95% CI: non assessable, p=0.01, respectively, Figure 1. The observed increased risk in patients with an abnormal vs a normal FFRCT test result persisted after adjustment for degree of stenosis by CCTA (< / ≥50%) and amount of CAC (< / ≥400): PE, adjusted RR: 2.5; 95% CI: 1.2–5.2, p=0.02, and SE, adjusted RR: 8.0; 95% CI: 2.1–30.2, p=0.002.
Conclusion
Patients with stable chest pain, stenosis by CTA and a normal FFRCT test result have a low risk of adverse outcomes during 3 years of follow-up. An abnormal FFRCT identifies patients at increased risk of death or spontaneous MI. These associations are consistent in patients with high levels of CAC.
Funding Acknowledgement
Type of funding sources: None.
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FFRCT and recurrent symptoms in patients with stable chest pain. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehac544.200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Introduction
The major benefit of coronary revascularization when compared with optimal medical treatment (OMT) in patients with stable chest pain (CP) relates to improvement of symptoms and reduction of reinterventions. Non-invasive methods are warranted to discriminate between patients at low and high risk of recurrent CP for subsequent guidance of antianginal treatment (invasive or OMT).
Purpose
To evaluate the association between coronary CT angiography (CTA) derived fractional flow reserve (FFRCT), recurrent CP and quality of life (QOL) in patients with new onset stable CP and stenosis by CTA.
Methods
Multicenter cohort 3-year follow-up sub-study of 769 patients from the Assessing Diagnostic Value of Non-invasive FFRCT in Coronary Care (ADVANCE) registry at three Danish sites, the “ADVANCE-DK Registry”. All patients had at least one ≥30% coronary stenosis by CTA and underwent subsequent core laboratory FFRCT analysis by HeartFlow. An abnormal FFRCT was defined as the lowest in vessel FFRCT value ≤0.80. Patients were classified according to completeness of revascularization by FFRCT: 1) completely revascularized (CR-FFRCT), all coronary arteries with an abnormal FFRCT test result revascularized; 2) incompletely revascularized (IR-FFRCT), ≥1 coronary artery with an abnormal FFRCT test result not revascularized. All patients completed the Seattle Angina Questionnaire (SAQ-7), the EuroQol questionnaire (EQ-5D-5L) and graded (0–100) overall health using the EQ VAS scale at 3-year follow-up. Recurrent CP was defined as CP within the last 4 weeks prior to this follow-up.
Results
Patient characteristics are given in Table 1. At follow-up 23% patients reported recurrent CP. An abnormal vs a normal FFRCT increased the risk of recurrent CP, 27% vs 15%, RR: 1.82; 95% CI: 1.31–2.52, p<0.001. Amongst patients with abnormal FFRCT, revascularization (+/−) was associated to a numerical, but not statistical significantly, reduced risk of recurrent CP, 23% vs 30%, RR: 0.76; 95% CI: 0.56–1.03, p=0.07. IR-FFRCT vs CR-FFRCT had a higher risk for recurrent CP, 31% vs 13%, RR: 2.34; 95% CI: 1.48–3.68, p<0.001, whilst no difference was observed for CR-FFRCT vs normal FFRCT, 13% vs 15%, RR: 0.92; 95% CI: 0.54–1.54, p=0.74. IR-FFRCT vs CR-FFRCT or normal FFRCT, had lower SAQ-7, EQ-5D-5L and EQ-VAS scores, Table 1, all p<0.005. Scores for three selected SAQ-7 domains are shown in Figure 1. Use of antianginal medicine was higher in IR-FFRCT compared to CR-FFRCT and normal FFRCT, mean ± SD: 1.2±0.05 vs 1.0±0.04, p=0.02.
Conclusion
An abnormal FFRCT identifies patients with an increased risk of recurrent CP up to 3 years after index testing. Completeness of revascularization by FFRCT reclassifies patients with abnormal FFRCT into groups with low and high risk for recurrent CP and impaired QOL.
Funding Acknowledgement
Type of funding sources: None.
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Completeness of revascularization by FFRCT and prognosis in stable chest pain. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehac544.201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Introduction
Major randomized trials of patients with stable chest pain (CP) demonstrated no prognostic benefits of coronary revascularization over optimal medical treatment (OMT). However, in a recent large-scale study, completeness of revascularization was associated with a reduced risk of all-cause death and non-fatal myocardial infarction (MI).
Purpose
To evaluate the association between completeness of revascularization relative to the result of coronary CT angiography (CTA) derived fractional flow reserve (FFRCT) and 3-year prognosis in patients with new onset stable CP and coronary stenosis.
Methods
Multicenter cohort 3-year follow-up sub-study of 900 patients from the Assessing Diagnostic Value of Non-invasive FFRCT in Coronary Care (ADVANCE) registry at three Danish sites, the “ADVANCE-DK Registry”. All patients had at least one ≥30% coronary stenosis by CTA and underwent subsequent core laboratory FFRCT analysis by HeartFlow. The FFRCT result was abnormal when ≤0.80 (2 cm distal to stenosis). Patients were classified according to completeness of revascularization by FFRCT: 1) completely revascularized (CR-FFRCT), all coronary arteries with an abnormal FFRCT test result revascularized; 2) incompletely revascularized (IR-FFRCT), ≥1 coronary artery with an abnormal FFRCT test result not revascularized. The primary endpoint (PE) was a composite of all-cause death and spontaneous MI. The secondary endpoint (SE) was a composite of cardiovascular (CV) death and spontaneous MI.
Results
Patient characteristics are given in Table 1. In total 36 (4.0%) patients suffered a PE (all-cause death, n=24; MI, n=12) and 22 (2.4%) an SE (CV death, n=10; MI, n=12). Overall, an abnormal vs a normal FFRCT test result was associated with an increased risk of both the PE, 6.6% vs 2.1%, relative risk (RR): 3.1; 95% CI: 1.6–6.3, p<0.001 and of the SE, 5.0% vs 0.6%, RR: 8.7; 95% CI: non assessable, p<0.001. In patients with abnormal FFRCT, revascularization vs no revascularization did not reduce the risk of the PE or the SE (data not shown). Patients with IR-FFRCT vs CR-FFRCT had a numerical, but not statistical significantly, increased risk of the PE, 8.6% vs 4.2%, RR: 2.14; 95% CI: 0.87–5.26, p=0.10), and an increased risk of the SE, 7.1% vs 2.4%, RR: 3.13; 95% CI: 1.02–9.63, p=0.04, Figure 1. In CR-FFRCT versus normal FFRCT no difference in the risk of the PE or the SE was observed, Figure 1. Univariate sensitivity analyses performed in the IR-FFRCT group did not reveal any differences in the risk of the PE or the SE after adjustment for neither statin therapy at follow-up (−/+), baseline risk variables (< / ≥3), amount of CAC (< / ≥400), degree of stenosis by CTA (< / ≥50%) nor referral to ICA (−/+).
Conclusion
In symptomatic patients with coronary stenosis by CTA, incomplete revascularization determined by FFRCT is associated with an increased risk of adverse cardiovascular outcomes compared to complete revascularization.
Funding Acknowledgement
Type of funding sources: None.
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[Genetic testing in autism spectrum disorder]. Ugeskr Laeger 2022; 184:V04220253. [PMID: 36065862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Autism spectrum disorders (ASD) have a complex genetic component comprising both frequent polygenic and rare monogenic factors. Research is conducted in methods used to calculate polygenic risk scores, which are not applicable in clinical practice. Advances in genomic technology have identified several monogenic causes, and genetic testing may be offered to persons with ASD where a monogenic etiology is suspected. Herein, we provide an overview of the current knowledge and present the first national recommendation regarding genetic testing in ASD.
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Is CT-derived fractional flow reserve superior to ischaemia testing? Expert Rev Cardiovasc Ther 2022; 20:165-168. [PMID: 35345959 DOI: 10.1080/14779072.2022.2059466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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No prognostic benefit of multimodality imaging-guided left ventricular lead placement in cardiac resynchronization therapy: Long-term follow-up of the ImagingCRT study. Europace 2021. [DOI: 10.1093/europace/euab116.439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: Foundation. Main funding source(s): Aarhus University, the Danish Heart Foundation, Health Research Foundation of Central Denmark Region, and Gangstedfonden.
Background
Observational data indicate that left ventricular (LV) lead placement at the latest contracting region and separate from myocardial scar is associated with improved prognosis in cardiac resynchronization therapy (CRT). In a double-blinded, randomized controlled trial (ImagingCRT), we tested the strategy of multimodality imaging-guided LV lead placement towards the latest mechanically activated non-scarred myocardial segment in CRT. Patients were included between 2011 and 2014 and allocated either to (1) imaging-guided LV lead placement using cardiac computed tomography, 99mTechnetium myocardial perfusion imaging, and speckle-tracking echocardiography (imaging group, n = 89) or to (2) routine LV lead implantation in a posterolateral region with late electrical activation (control group, n = 93). The multimodality imaging-guided strategy was found to reduce proportion of non-responders to CRT after 6 months. Impact on long-term clinical outcome is unknown.
Purpose
To evaluate the long-term effect of individualized multimodality imaging-guided LV lead placement compared to a routine fluoroscopic approach on the composite endpoint of death or heart failure (HF) hospitalization after CRT.
Method
We reviewed follow-up data until November 2020 for all 182 patients included in the ImagingCRT trial for the occurrence of HF hospitalization and all-cause death. Continuous variables are presented as median (interquartile range) or mean ± standard deviation. We used Kaplan-Meier plot and Cox proportional hazard regression analysis (unadjusted) to assess the risk of HF hospitalization and all-cause death, and used log-rank test for comparison between the two groups.
Results
All patients had standard CRT indication (left bundle branch block, New York Heart Association functional class II/ III/ IV 84 [46%]/ 92 [51%]/ 6 [3%], LV ejection fraction 25 ± 6%, QRS width 166 ± 22 milliseconds). Mean age was 70 ± 9 years, and 39 (21%) were female. During a median follow-up period of 6.7 years (3.3–7.9 years), the proportion of patients meeting the composite endpoint of HF hospitalization (n = 45 [25%]) or all-cause death (n = 56 [31%]) was 60% (n = 53) in the imaging group compared with 52% (n = 48) in the control group (hazard ratio [HR] 1.22, 95% confidence interval [CI] 0.83–1.81, p = 0.31) (Figure 1).
Neither the risk of HF hospitalization (HR 1.11, 95% CI 0.62–1.99, p = 0.72) or of all-cause death differed between the two groups (HR 1.23, 95% CI 0.82–1.85, p = 0.32).
Conclusion
An individualized multimodality imaging-guided strategy targeting LV lead placement towards the latest mechanically activated non-scarred myocardial segment during CRT implantation did not reduce the composite outcome of HF hospitalization or all-cause death during long-term follow-up. Abstract Figure 1
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Anode heel effect: Does it impact image quality in digital radiography? A systematic literature review. Radiography (Lond) 2021; 27:976-981. [PMID: 33741222 DOI: 10.1016/j.radi.2021.02.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 02/25/2021] [Accepted: 02/26/2021] [Indexed: 01/28/2023]
Abstract
INTRODUCTION The anode heel effect can be used to optimize image quality and/or patient dose in digital radiography (DR). In film-screen radiography, the effect can equalize optical density in regions of varying attenuation. Clinical experience suggests that the implementation of DR has led to less awareness of anode orientation. Post-processing is assumed to compensate, but may also alter image impression and potentially obscure image details. Published evidence was examined for the influence of the anode heel effect on image quality in DR. METHOD A systematic literature search was carried out using PubMed, Embase, and Web of Science databases. Title and abstracts were screened blinded by three authors, according to in-/exclusion criteria, followed by full-text analysis for final inclusion. Studies where technical and/or visual image quality were reported, was included. All studies were analyzed and assigned quality scores, according to relevant questions. The authors devised a scoring system based on reported information pertaining to reproducibility, interpretation, and generalizability of the methods and conclusions. RESULTS Five studies were included of heterogeneous design, each with methodological shortcomings. Only a few anatomical areas were covered. Very few patients were examined, and in no studies were images evaluated by radiologists or reporting radiographers. Relevant information such as post-processing, image quality criteria and analysis was insufficient in most studies, making reproduction difficult. Results were contradictory, especially concerning technical vs visual image quality. CONCLUSION Limited published evidence was found quantifying the influence of the anode heel effect on image quality using DR technology. More methodologically, robust studies are needed. The published evidence neither proves nor disproves the impact of the heel effect on image quality in DR. IMPLICATIONS FOR PRACTICE Based on a systematic review, no firm recommendations for anode orientation relating to image quality in DR can be provided.
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Exploring the patient perspectives of mobile X-ray in nursing homes - A qualitative explorative pilot study. Radiography (Lond) 2020; 27:279-283. [PMID: 32919898 DOI: 10.1016/j.radi.2020.08.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 08/18/2020] [Accepted: 08/20/2020] [Indexed: 11/19/2022]
Abstract
INTRODUCTION For patients with dementia, behaviour and reactions to stimuli can change and an X-ray examination in the hospital can have be a frightening experience. The aim of this study was to identify the experiences and perspectives of patients with dementia and their caregivers on receiving a mobile x-ray examination in nursing homes. METHODS This study was designed as a qualitative study using patient observation and semi structured interviews, with a phenomenology-hermeneutic approach. In total, 23 patients were observed during X-ray examinations in nursing homes, and six semi structured interviews were conducted with the caregivers who participated in the examination. RESULTS The observations and interviews indicated that a known environment, a recognizable framework and calmness were central for a patient with dementia. The patients appeared calm and relaxed during the examination in their usual environment (nursing homes) where there are less stimuli and impressions based of the observations. CONCLUSION Mobile X-ray examinations for patients with dementia living in nursing homes had a positive impact on patients' reactions towards the X-ray examination. The examinations were performed in the patients' usual and safe environments, where impressions and stimuli were less disturbing for patients with dementia. IMPLICATIONS FOR PRACTICE The mobile x-ray unit can be of benefit for patients suffering from dementia and result in less impact. The patients living in nursing homes have the opportunity to be examined in their familiar environment, because of the mobile x-ray unit.
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Mitochondrial Disease Caused by a Novel Homozygous Mutation (Gly106del) in the SCO1 Gene. Neonatology 2019; 116:290-294. [PMID: 31352446 DOI: 10.1159/000499488] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 03/05/2019] [Indexed: 11/19/2022]
Abstract
The cytochrome C oxidase assembly protein SCO1 gene encodes a mitochondrial protein essential for the mammalian energy metabolism. Only three pedigrees of SCO1mutations have thus far been reported. They all presented with lactate acidosis and encephalopathy. Two had hepatopathy and hypotonia, and the other presented with intrauterine growth retardation and hypertrophic cardiomyopathy leading to cardiac failure. Mitochondrial disease may manifest in neonates, but early diagnosis has so far been difficult. Here, we present a novel mutation in the SCO1 gene: in-frame deletion (Gly106del)with a different phenotype without encephalopathy, hepatopathy, hypotonia, or cardiac involvement. Within the first 2 h the girl developed hypoglycemia and severe chronic lactate acidosis. Because of the improved technique in whole exome sequencing, an early diagnosis was made when the girl was only 9 days old, which enabled the prediction of prognosis as well as level of treatment. She died at 1 month of age.
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P3189Aspirin for prevention of cardiovascular events: an analysis of 27,451 patients from the Western Denmark Cardiac Computed Tomography Registry. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy563.p3189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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11
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3288CT-derived fractional flow reserve in patients with stable angina pectoris: A real world follow-up study. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy563.3288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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The analgesic effect of a popliteal plexus blockade after total knee arthroplasty: A feasibility study. Acta Anaesthesiol Scand 2018; 62:1127-1132. [PMID: 29797704 DOI: 10.1111/aas.13145] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Revised: 04/13/2018] [Accepted: 04/18/2018] [Indexed: 11/28/2022]
Abstract
INTRODUCTION An obturator nerve block (ONB) and a femoral triangle block (FTB) provide effective analgesia after total knee arthroplasty (TKA) without impeding the ambulation, although the ONB produces motor blockade of the hip adductor muscles. The popliteal plexus (PP) in the popliteal fossa is formed by contribution from the tibial nerve and the posterior obturator nerve, innervating intraarticular genicular structures and the posterior capsule of the knee. We hypothesised that a popliteal plexus block (PPB) as a supplement to an FTB would reduce pain after TKA without anaesthetising motor branches from the sciatic nerve in the popliteal fossa. AIM To assess the analgesic effect of adding a PPB to an FTB in 10 subjects with significant pain after TKA. METHODS All subjects underwent unilateral TKA with spinal anaesthesia and received an FTB. The cutaneous sensation and the postoperative pain were assessed. The primary outcome was the proportion of subjects with pain above numeric rating scale (NRS) 3 followed by a reduction to NRS 3 or below after conducting a PPB. RESULTS Ten subjects with a median pain of NRS 5.5 (interquartile range [IQR] 4-8) after unilateral TKA received a PPB. All 10 subjects experienced a reduction in pain to NRS 3 or below (NRS 1.5 [IQR 0-3]) within a mean time of 8.5 (95% CI 6.8-10.2) minutes. Three subjects were completely pain free after the PPB. The ankle muscle strength was not affected. CONCLUSIONS The PPB provided effective pain relief without affecting the ankle muscle strength in all 10 subjects with significant pain after TKA and an FTB.
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269Left ventricular regional remodeling and lead position during CRT. Europace 2018. [DOI: 10.1093/europace/euy015.081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Effect of sodium nitrite on renal function and sodium and water excretion and brachial and central blood pressure in healthy subjects: a dose-response study. Am J Physiol Renal Physiol 2017; 313:F378-F387. [PMID: 28490529 DOI: 10.1152/ajprenal.00400.2016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 04/21/2017] [Accepted: 05/02/2017] [Indexed: 01/12/2023] Open
Abstract
Sodium nitrite (NaNO2) is converted to nitric oxide (NO) in vivo and has vasodilatory and natriuretic effects. Our aim was to examine the effects of NaNO2 on hemodynamics, sodium excretion, and glomerular filtration rate (GFR). In a single-blinded, placebo-controlled, crossover study, we infused placebo (0.9% NaCl) or 0.58, 1.74, or 3.48 μmol NaNO2·kg-1·h-1 for 2 h in 12 healthy subjects, after 4 days of a standard diet. Subjects were supine and water loaded. We measured brachial and central blood pressure (BP), plasma concentrations of renin, angiotensin II, aldosterone, arginine vasopressin (P-AVP), and plasma nitrite (P-[Formula: see text]), GFR by Cr-EDTA clearance, fractional excretion of sodium (FENa) free water clearance (CH2O), and urinary excretion rate of guanosine 3',5'-cyclic monophosphate (U-cGMP). The highest dose reduced brachial systolic BP (5.6 mmHg, P = 0.003), central systolic BP (5.6 mmHg, P = 0.035), and CH2O (maximum change from 3.79 to 1.27 ml/min, P = 0.031) and increased P-[Formula: see text] (from 0.065 to 0.766 μmol/l, P < 0.001), while reducing U-cGMP (from 444 to 247 pmol/min, P = 0.004). GFR, FENa, P-AVP, and the components in the renin-angiotensin-aldosterone system did not change significantly. In conclusion, intravenous NaNO2 induced a dose-dependent reduction of brachial and central BP. The hemodynamic effect was not mediated by the renin-angiotensin-aldosterone system. NaNO2 infusion resulted in a vasopressin-independent decrease in CH2O and urine output but no change in urinary sodium excretion or GFR. The lack of increase in cGMP accompanying the increase in [Formula: see text] suggests a direct effect of nitrite or nitrate on the renal tubules and vascular bed with little or no systemic conversion to NO.
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Effects of atorvastatin on systemic and renal NO dependency in patients with non-diabetic stage II-III chronic kidney disease. Br J Clin Pharmacol 2015; 78:789-99. [PMID: 24697877 DOI: 10.1111/bcp.12390] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 03/25/2014] [Indexed: 12/20/2022] Open
Abstract
AIMS Clinical trials suggest that statins have beneficial effects on the cardiovascular system independent from their cholesterol lowering properties. In patients with chronic kidney disease stage II-III, we tested the hypothesis that atorvastatin increased systemic and renal nitric oxide (NO) availability using L-N(G) -monomethyl arginine (L-NMMA) as an inhibitor of NO production. METHODS In a randomized, placebo-controlled, crossover study patients were treated with atorvastatin for 5 days with standardized diet and fluid intake. Glomerular filtration reate (GFR), fractional excretions of sodium (FENa ), urinary excretion of aquaporin-2 (u-AQP2) and epithelial sodium channels (u-ENaCγ ), vasoactive hormones (renin, angiotensin II, aldosterone, arginine vasopressin, endothelin-1 and brain natriuretic peptide) and central blood pressure (BP) estimated by applanation tonometry were measured before and after systemic administration of the NO inhibitor L-NMMA. RESULTS Atorvastatin caused a significant reduction in U-ENaCγ , but sodium excretion, C H 2 O , FENa and u-AQP2 were not changed by atorvastatin. L-NMMA reduced renal effect variables, including GFR, FENa and u-ENaCγ and increased brachial BP and central BP to a similar extent during both treatments. Vasoactive hormones were changed in the same way by L-NMMA during atorvastatin and placebo treatment. CONCLUSION During, atorvastatin and placebo treatment, inhibition of nitric oxide synthesis induced the same response in brachial and central blood pressure, GFR, renal tubular function and vasoactive hormones. Thus, the data do not support that atorvastatin changes nitric oxide availability in patients with mild nephropathy. The reduced u-ENaC may reflect changes in sodium absorption in the nephron induced by atorvastatin.
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Practicability of avoiding hypothermia in resuscitation room phase in severely injured patients. J Med Eng Technol 2015; 39:223-5. [PMID: 25879707 DOI: 10.3109/03091902.2015.1035767] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Hypothermia in severely injured patients is a high demanding situation resulting from an effect of injury severity, surrounding temperature at trauma site and admittance. This article reviews the possible options to combat hypothermia in the resuscitation room with respect to practicability. This review summarizes available passive and active re-warming techniques and trys to offer a practicable chronology to restore normothermia. Resources should be applied depending on the availability of each institution and manifestation of hypothermia, but there is a strong demand for improvements with respect to practicability, convenience and safety for the patient.
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Effect of vasopressin antagonism on renal handling of sodium and water and central and brachial blood pressure during inhibition of the nitric oxide system in healthy subjects. BMC Nephrol 2014; 15:100. [PMID: 24965902 PMCID: PMC4079642 DOI: 10.1186/1471-2369-15-100] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 06/19/2014] [Indexed: 11/10/2022] Open
Abstract
Background Tolvaptan is a selective vasopressin receptor antagonist (V2R) that increases free water excretion. We wanted to test the hypotheses that tolvaptan changes both renal handling of water and sodium and systemic hemodynamics during basal conditions and during nitric oxide (NO)-inhibition with L-NG-monomethyl-arginine (L-NMMA). Methods Nineteen healthy subjects were enrolled in a randomized, placebo-controlled, double-blind, crossover study of two examination days. Tolvaptan 15 mg or placebo was given in the morning. L-NMMA was given as a bolus followed by continuous infusion during 60 minutes. We measured urine output(UO), free water clearance (CH2O), fractional excretion of sodium (FENa), urinary aquaporin-2 channels (u-AQP2) and epithelial sodium channels (u-ENaCγ), plasma vasopressin (p-AVP), central and brachial blood pressure(cBP, bBP). Results During baseline conditions, tolvaptan caused a significant increase in UO, CH2O and p-AVP, and FENa was unchanged. During L-NMMA infusion, UO and CH2O decreased more pronounced after tolvaptan than after placebo (-54 vs.-42% and -34 vs.-9% respectively). U-AQP2 decreased during both treatments, whereas u-ENaCγ decreased after placebo and increased after tolvaptan. CBP and bBP were unchanged. Conclusion During baseline conditions, tolvaptan increased renal water excretion. During NO-inhibition, the more pronounced reduction in renal water excretion after tolvaptan indicates that NO promotes water excretion in the principal cells, at least partly, via an AVP-dependent mechanism. The lack of decrease in u-AQP2 by tolvaptan could be explained by a counteracting effect of increased plasma vasopressin. The antagonizing effect of NO-inhibition on u-ENaC suggests that NO interferes with the transport via ENaC by an AVP-dependent mechanism.
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[Urgent revascularisation can preserve renal function in a patient with severe hypertension because of renal artery stenosis]. Ugeskr Laeger 2013; 175:V09130542. [PMID: 25353610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We present a case of a 61-year-old woman with renal artery stenosis in a solitary functional kidney. The patient was admitted with recurrent severe hypertension, flash pulmonary oedema and acute kidney failure. She underwent surgical intervention, after which blood pressure and plasma creatinine level remained normal during a 11-year follow-up. Renal artery stenosis may have a serious course with flash pulmonary oedema and dialysis-dependent renal failure. Urgent revascularisation may be the only option to avoid pulmonary oedema and preserve renal function in patients with renal artery stenosis.
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Cost-effectiveness of ultrasound vs nerve stimulation guidance for continuous sciatic nerve block. Br J Anaesth 2012; 109:804-8. [PMID: 22855632 DOI: 10.1093/bja/aes259] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND This study assessed the cost-effectiveness of ultrasound (US) vs nerve stimulation (NS) guidance for continuous sciatic nerve block in Danish elective patients undergoing major foot and ankle surgery. METHODS > A cost-effectiveness analysis was conducted alongside a randomized controlled trial. A total of 100 consecutive patients were randomly assigned to either traditional electrical NS or US technique for catheter insertion guidance. Information on effects and costs were collected prospectively. An incremental cost-effectiveness ratio (ICER) was calculated as the extra cost per extra successful nerve block. The robustness of the ICER was investigated using 4000 non-parametric bias-corrected bootstrap replicates to calculate the likelihood that US leads to better effect and lower costs compared with NS guidance. RESULTS The mean ICER was negative, indicating that US was a dominating technology providing both higher quality and lower costs. The likelihood of US being more effective and cheaper than NS was estimated to 84.7%. CONCLUSIONS In this trial, US was cost-effective. Assuming that the results are fairly generalizable, US should be the preferred catheter insertion technique in larger anaesthesia departments.
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Gene expression is differently affected by pimecrolimus and betamethasone in lesional skin of atopic dermatitis. Allergy 2012; 67:413-23. [PMID: 22142306 DOI: 10.1111/j.1398-9995.2011.02747.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
BACKGROUND Topical corticosteroids and calcineurin inhibitors are well-known treatments of atopic dermatitis (AD) but differ in their efficacy and side effects. We recently showed that betamethasone valerate (BM) although clinically more efficient impaired skin barrier repair in contrast to pimecrolimus in AD. OBJECTIVE This study elucidates the mode of action of topical BM and pimecrolimus cream in AD. METHODS Lesional AD skin samples after topical treatment with either BM or pimecrolimus were subjected to gene expression profile analysis. RESULTS Betamethasone valerate resulted in a significant reduction in mRNA levels of genes encoding markers of immune cells and inflammation, dendritic cells, T cells, cytokines, chemokines, and serine proteases, whereas pimecrolimus exerted minor effects only. This corroborates the clinical finding that BM reduces inflammation more effectively than pimecrolimus. Genes encoding molecules important for skin barrier function were differently affected. Both BM and pimecrolimus normalized the expression of filaggrin and loricrin. BM, but not pimecrolimus, significantly reduced the expression of rate-limiting enzymes for lipid synthesis and the expression of involucrin and small proline-rich proteins, which covalently bind ceramides. This may explain the lack of restoration of functional stratum corneum layers observed after BM treatment. CONCLUSION The gene expression profiles are consistent with our previous findings that corticosteroids may exert a more potent anti-inflammatory effect but may impair the restoration of the skin barrier. Corticosteroids are still the main treatment for severe and acutely exacerbated AD; pimecrolimus may be preferable for long-term treatment and stabilization.
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A Monte Carlo investigation of contaminant electrons due to a novel in vivo transmission detector. Phys Med Biol 2011; 56:1207-23. [PMID: 21285480 DOI: 10.1088/0031-9155/56/4/020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A novel transmission detector (IBA Dosimetry, Germany) developed as an IMRT quality assurance tool, intended for in vivo patient dose measurements, is studied here. The goal of this investigation is to use Monte Carlo techniques to characterize treatment beam parameters in the presence of the detector and to compare to those of a plastic block tray (a frequently used clinical device). Particular attention is paid to the impact of the detector on electron contamination model parameters of two commercial dose calculation algorithms. The linac head together with the COMPASS transmission detector (TRD) was modeled using BEAMnrc code. To understand the effect of the TRD on treatment beams, the contaminant electron fluence, energy spectra, and angular distributions at different SSDs were analyzed for open and non-open (i.e. TRD and block tray) fields. Contaminant electrons in the BEAMnrc simulations were separated according to where they were created. Calculation of surface dose and the evaluation of contributions from contaminant electrons were performed using the DOSXYZnrc user code. The effect of the TRD on contaminant electrons model parameters in Eclipse AAA and Pinnacle(3) dose calculation algorithms was investigated. Comparisons of the fluence of contaminant electrons produced in the non-open fields versus open field show that electrons created in the non-open fields increase at shorter SSD, but most of the electrons at shorter SSD are of low energy with large angular spread. These electrons are out-scattered or absorbed in air and contribute less to surface dose at larger SSD. Calculated surface doses with the block tray are higher than those with the TRD. Contribution of contaminant electrons to dose in the buildup region increases with increasing field size. The additional contribution of electrons to surface dose increases with field size for TRD and block tray. The introduction of the TRD results in a 12% and 15% increase in the Gaussian widths used in the contaminant electron source model of the Eclipse AAA dose algorithm. The off-axis coefficient in the Pinnacle(3) dose calculation algorithm decreases in the presence of TRD compared to without the device. The electron model parameters were modified to reflect the increase in electron contamination with the TRD, a necessary step for accurate beam modeling when using the device.
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The skin's barrier. GIORN ITAL DERMAT V 2009; 144:689-700. [PMID: 19907407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The skin provides an effective barrier between the organism and the environment, preventing the invasion of pathogens and fending off chemical and physical assaults, as well as the unregulated loss of water and solutes. In this review we provide an overview of several components of the physical barrier, as well as how barrier function is regulated and altered in association with dermatoses. The physical barrier localized primarily in the stratum corneum (SC) and consists of protein-enriched cells (corneocytes with cornified envelope and cytoskeletal elements, as well as corneodesmosomes) and lipid-enriched intercellular domains. The nucleated epidermis, with its tight, gap and adherens junctions, additional desmosomes and cytoskeletal elements, also contributes to the barrier. Lipids are synthesized in the keratinocytes during epidermal differentiation and are then extruded into the extracellular domains, where they form lipid-enriched extracellular layers. The cornified cell envelope, a robust protein/lipid polymer structure, is located below the cytoplasmic membrane on the exterior of the corneocytes. Ceramides A and B, forming the backbone for the subsequent addition of free ceramides, free fatty acids and cholesterol in the SC, are covalently bound to cornified envelope proteins. Filaggrin is cross-linked to the cornified envelope and aggregates keratin filaments into macrofibrils. Cytokines, cAMP and calcium influence the formation and maintenance of barrier function. Changes in lipid composition and epidermal differentiation lead to a disturbed skin barrier, which allows the entry of environmental allergens, immunological reaction and inflammation in atopic dermatitis. A disturbed skin barrier is an important component in the pathogenesis of contact dermatitis, ichthyosis, psoriasis, and atopic dermatitis.
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Abstract
BACKGROUND Insertion of central venous catheters (CVCs) is a procedure associated with a varying risk of complications, depending on the setting and the skill of the clinician who undertakes the procedure. The aim of this study was to monitor the complication rate of CVC insertion and evaluate the value of routine chest X-ray control. METHODS Anesthesiologists at eight hospitals filled in a questionnaire immediately after insertion of a CVC. The post-procedural clinical evaluation, including expected complications, was compared to actual radiological findings. Chest X-ray was ordered by the anesthesiologist, and described by staff radiologists. RESULTS The clinicians had from 2 months to 30 years of experience as anesthesiologists, and trainees inserted 34% and specialists 66% of the catheters, using landmark techniques. Over a period of 2 months, 473 CVC-insertion procedures were included in the investigation. Two patients (0.4%) had a pneumothorax: one was among the 11 cases in which the clinician suspected complications after the procedure, and another was found in a high-risk patient 13 h after CVC insertion. Both patients were treated successfully with chest tubes. The favorite approach was right vena jugularis interna with 324 (69%) catheters; of these patients one had a pneumothorax, catheter-tip placement was correctly predicted in 317 (97%), and no catheters were repositioned. CONCLUSION In the hands of trained clinicians, insertion of CVCs is a safe procedure. We found no value of routine X-ray control and omission of routine chest X-ray must be considered.
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Determination of field size limitations in stereotactic and intensity modulated radiotherapy. AUSTRALASIAN PHYSICS & ENGINEERING SCIENCES IN MEDICINE 2003; 26:168-72. [PMID: 14995061 DOI: 10.1007/bf03179177] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
For dose measurement in small photon fields, different detectors are currently in use: TLD, semiconductor, diamond-detector, film, etc. But for absolute dosimetry, ionization chambers show the most advantages. To meet the basic dosimetrical requirements for lateral electron equilibrium the field size F must not remain under specified values: i.e. 5.2 x 5.2 cm2 for 15 MeV X-bremsstrahlung. As well as increasing the focus-chamber-distance, changing the physical density of the build-up material in the close vicinity of the chamber will be helpful to determine the output factor OF for smaller fields. By means of a correction factor, k(mat), this is taken into account. For a 6 MeV X and a 15 MeV X-bremsstrahlung of linear accelerators the lower limit of the field size F is determined: F > or = 0.8 cm. This value is mainly dependent on the diameter of the focal-spot (phi = 3 mm) of the treatment unit including design characteristics of the treatment head. Beside the dosimetrical aspects, some geometrical parameters have to be considered, when accuracy of dose application should remain on the same level as in medium and large field treatment (4 cm < or = F < or = F(max)). To keep dose-volume errors as low as +/- 10 % (diameter of PTV: 20 mm), the mean total error delta of CT-scanning (delta(p)), planning (delta(pl)), patient positioning (delta(x)), and treatment unit instabilities (delta(m)) should not exceed +/- 0.8 mm.
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LDL receptor mutation genotype and vascular disease phenotype in heterozygous familial hypercholesterolaemia. Clin Genet 2002; 61:408-15. [PMID: 12121347 DOI: 10.1034/j.1399-0004.2002.610603.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Patients with homozygous familial hypercholesterolaemia (FH) caused by receptor-negative, low-density lipoprotein (LDL) receptor gene mutations have higher concentrations of LDL-cholesterol in plasma and earlier onset of cardiovascular disease (CVD) than patients homozygous for receptor-defective, LDL receptor mutations. In contrast, it is uncertain whether the severity of atherosclerotic disease differs in heterozygous FH caused by receptor-negative and receptor-defective mutations. The present authors investigated the influence of LDL receptor mutation type on the clinical phenotype in 31 patients with heterozygous FH caused by the receptor-negative, Trp23-stop mutation and in 31 patients heterozygous for the receptor defective Trp66-Gly mutation. Untreated levels of plasma LDL-cholesterol and calculated cholesterol-years score did not differ significantly between the two groups of patients. Detection of vascular disease was based on two approaches: (1) measurement of coronary calcification by spiral computed tomography (CT) scanning; and (2) ultrasonic measurement of carotid intima-media thickness (IMT). Age was significantly correlated to the presence of coronary calcification, but controlling for relevant cofactors, there was no evidence that the receptor-negative mutation caused more calcification than the receptor-defective mutation. Furthermore, carotid IMT was significantly influenced by plasma concentrations of Lp(a) and triglycerides, as well as by age, sex and smoking status, but again, there was no statistically significant effect of LDL receptor gene mutational type. The similarity in vascular phenotypes was probably caused by a similar life-long burden of LDL-cholesterol in the two groups of patients.
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Mandatory or elective? J Am Dent Assoc 2001; 132:148, 150. [PMID: 11217584 DOI: 10.14219/jada.archive.2001.0138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Impaired cutaneous permeability barrier function, skin hydration, and sphingomyelinase activity in keratin 10 deficient mice. J Invest Dermatol 2000; 115:708-13. [PMID: 10998148 DOI: 10.1046/j.1523-1747.2000.00103.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Point mutations in the suprabasal cytokeratins 1 (K1) or 10 (K10) in humans have been shown to be the cause of the congenital ichthyosis epidermolytic hyperkeratosis. Recently, a K10 deficient mouse model was established serving as a model for epidermolytic hyperkeratosis. Homozygotes suffered from severe skin fragility and died shortly after birth. Heterozygotes developed hyperkeratosis with age. To see whether phenotypic abnormalities in the mouse model were associated with changes in skin barrier function and skin water content we studied basal transepidermal water loss and capacity for barrier repair after experimental barrier disruption as well as stratum corneum hydration. Also, we determined the activities of acid and neutral sphingomyelinase key enzymes of the tumor necrosis factor and interleukin-1 signal transduction pathways generating the ceramides most important for epidermal permeability barrier homeostasis. Neonatal homozygotes showed an 8-fold increase in basal transepidermal water loss compared with wild type controls. Adult heterozygotes exhibited delayed barrier repair after experimental barrier disruption. Stratum corneum hydration was reduced in homozygous and heterozygous mice. Acid sphingomyelinase activity, which is localized in the epidermal lamellar bodies and generates ceramides for extracellular lipid lamellae in the stratum corneum permeability barrier, was reduced in homozygous as well as heterozygous animals. Neutral sphingomyelinase activity, which has a different location and generates ceramides involved in cell signaling, was increased. The reduction in acid sphingomyelinase activity may explain the recently described decreased ratio of ceramides to total lipids in K10 deficient mice. In summary, our results demonstrate the crucial role of the keratin filament for permeability barrier function and stratum corneum hydration.
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Evaluation of anthelmintic activity in captive wild ruminants by fecal egg reduction tests and a larval development assay. J Zoo Wildl Med 2000; 31:348-52. [PMID: 11237142 DOI: 10.1638/1042-7260(2000)031[0348:eoaaic]2.0.co;2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The effectiveness of anthelmintics was evaluated in four herds of captive ruminants, wapiti (Cervus elaphus), Armenian red sheep (Ovis orientalis), giraffe (Giraffa camelopardalis), and pronghorn (Antilocapra americana), by the use of fecal egg reduction tests (FERTs) and a commercial larval development assay (LDA) designed to evaluate susceptibility or resistance of nematodes to anthelmintics. Haemonchus sp. was the predominant nematode in the red sheep, giraffe, and pronghorn herds, whereas Ostertagia sp. and Trichostrongylus sp. were predominant in the wapiti. The LDA data indicated susceptibility by the worms to benzimidazoles except in the red sheep flock, which showed a high level of resistance. High levels of resistance to levamisole were seen in the worm populations from the wapiti and red sheep, moderate resistance in the pronghorn herd, and susceptibility in the giraffe herd. Worms were susceptible in all four herds to a combination of benzimidazole/levamisole. There was suspected avermectin resistance by Trichostrongylus sp. in the wapiti herd and by Haemonchus sp. in the giraffe. The FERTs agreed with the LDA in showing the Haemonchus in the giraffe was susceptible to fenbendazole and had suspected resistance to ivermectin, whereas Haemonchus in the red sheep and pronghorn were susceptible to ivermectin. There was correlation between the tests evaluating anthelmintics. The LDA is useful as a screening test in the selection of an anthelmintic for use in grazing ruminants, but the effectiveness of a drug in a host species may depend as much on the dose used, and the method of administration, as it does on the parasite's sensitivity to the anthelmintic.
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[The biologically equivalent dose (BED): how solid is the calculation of this factor? A consideration of margins of error of biologically equivalent dose]. RONTGENPRAXIS; ZEITSCHRIFT FUR RADIOLOGISCHE TECHNIK 2000; 52:355-60. [PMID: 10803050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
To predict the effect on tumours in radiotherapy, especially relating to irreversible effects, but also to realize the retrospective assessment the so called L-Q-model is relied on at present. Internal specific organ parameters, such as alpha, beta, gamma, Tp, Tk, and rho, as well as external parameters, so as D, d, n, V, and Vref, were used for determination of the biologically equivalent dose BED. While the external parameters are determinable with small deviations, the internal parameters depend on biological varieties and dispersions: in some cases the lowest value is assumed to be delta = +/- 25%. This margin of error goes on to the biologically equivalent dose by means of the principle of superposition of errors. In some selected cases (lung, kidney, skin, rectum) these margins of error were calculated exemplarily. The input errors especially of the internal parameters cause a mean error delta on the biologically equivalent dose and a dispersion of the single fraction dose d dependent on the organ taking into consideration, of approximately 8-30%. Hence it follows only a very critical and cautious application of those L-Q-algorithms in expert proceedings, and in radiotherapy more experienced based decisions are recommended, instead of acting only upon simple two-dimensional mechanistic ideas.
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Association of coronary heart disease with age-adjusted aortocoronary calcification in patients with familial hypercholesterolaemia. J Intern Med 2000; 247:479-84. [PMID: 10792562 DOI: 10.1046/j.1365-2796.2000.00630.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVES Existing algorithms of risk of coronary heart disease (CHD) do not pertain to patients with familial hypercholesterolaemia (FH), whose arteries have been exposed to hypercholesterolaemia since birth. We studied a cohort of FH patients to compare four diagnostic models of CHD: traditional risk factors of CHD (age, sex, cholesterol, hypertension, smoking and body mass index), cholesterol year score, and aortic as well as coronary calcium measured by spiral computed tomography (CT). SUBJECTS We invited 88 individuals with molecularly defined FH of whom 80 (91%) decided to participate. RESULTS Analysis of receiver operating characteristic curves showed that the age-adjusted coronary calcium score was more strongly associated with clinical manifestations of CHD than were traditional risk factors (P < 0.002), cholesterol year score (P << 0.0001), and the age-adjusted aortic calcium score (P < 0.0004). CONCLUSIONS Age-adjusted coronary calcium score shows promise as an indicator of CHD in FH patients.
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Roles for tumor necrosis factor receptor p55 and sphingomyelinase in repairing the cutaneous permeability barrier. J Clin Invest 1999; 104:1761-70. [PMID: 10606630 PMCID: PMC409877 DOI: 10.1172/jci5307] [Citation(s) in RCA: 144] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Epidermal TNF expression increases in response to cutaneous permeability barrier disruption and wound healing. TNF signaling is mediated by acid and neutral sphingomyelinases (A- and N-SMase), which generate ceramide, an important regulator of proliferation, differentiation, and apoptosis. In the epidermis, ceramide is known to be an integral part of the extracellular stratum corneum (SC) lipid bilayers that constitute the permeability barrier of the skin. We show here that topical application of TNF after experimental injury to the SC of hairless mice (hr(-/-)) enhances barrier repair. In TNF receptor p55-deficient (TNF-R55-deficient) mice (hr(+/+)), cutaneous barrier repair was delayed compared with wild-type (hr(+/+)) or TNF-R75-deficient (hr(+/+)) animals. After barrier disruption in hairless (hr(-/-)) and wild-type (hr(+/+)), but not in TNF-R55-deficient (hr(+/+)) mice, the enzymatic activities of both A-SMase and N-SMase were significantly enhanced. Stimulation of SMase activities was accompanied by an increase in C(24)-ceramide levels. Most A-SMase activity in hairless mice (hr(-/-)) was found in the outer epidermal cell layers and colocalized in the lamellar bodies with A-SMase and sphingomyelin. Reduction of epidermal A-SMase activity by the inhibitor imipramine resulted in delayed permeability barrier repair after SC injury. Together, these results suggest that TNF-R55 signaling pathways contribute to cutaneous permeability barrier repair through SMase-mediated generation of ceramide.
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[A linear quadratic offset filter for contrast improvement in digital reconstruction of radiography imaging for virtual simulation in radiotherapy]. RONTGENPRAXIS; ZEITSCHRIFT FUR RADIOLOGISCHE TECHNIK 1999; 52:203-5. [PMID: 10574030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
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Linking genotype to aorto-coronary atherosclerosis: a model using familial hypercholesterolemia and aorto-coronary calcification. Ann Hum Genet 1999; 63:511-20. [PMID: 11246453 DOI: 10.1017/s0003480099007800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/1999] [Indexed: 11/06/2022]
Abstract
Most studies of the pathogenesis of coronary heart disease occur between gene variants and biochemical or physiological variables known to be atherogenic. In many situations, however, the gene products are not necessarily known. We studied 17 families (n = 122) with mutations in the low density lipoprotein (LDL) receptor gene as a model in which to test formally for linkage directly between an atherogenic genotype and ischemic heart disease (IHD) or aorto-coronary calcified atherosclerosis. In each family one of three different mutations was found: the Trp66-Gly mutation, the Trp23-Stop mutation, or a ten kilobase deletion removing exons 3-6 of the LDL receptor gene. Genomic DNA was used to determine these mutations by either enzymatic cleavage assays or Southern blotting. Aorto-coronary calcification was significantly associated with age and plasma cholesterol. Sex, hypertension, BMI and smoking were not associated with aorto-coronary calcification. Nonparametric analysis indicated significant linkage of the LDL receptor gene locus to aortic (p < 0.00005) and to aorto-coronary calcified atherosclerosis (p < 0.00001). Assuming a dominant mode of inheritance, significant linkage was detected for aortic (LOD = 3.89) and aorto-coronary calcified atherosclerosis (LOD = 4.10). We suggest that the atherogenicity of variations in other genes could be assessed by a similar approach.
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Inpatient alcohol treatment in a private healthcare setting: which patients benefit and at what cost? Am J Addict 1999; 8:220-33. [PMID: 10506903 DOI: 10.1080/105504999305839] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
Abstract
This study investigated whether selected patients have better outcomes with inpatient than outpatient treatment. There were 93 inpatients and 80 outpatients with alcohol dependence who were evaluated at treatment entry to a private healthcare setting. Patients with multiple drinking-related consequences were less likely to return to significant drinking in the first 3 months after treatment ended if they had attended inpatient compared to outpatient treatment. Thus, inpatient appeared to have some advantage over outpatient treatment in the early recovery period for patients with multiple drinking-related consequences. The gap between inpatient and outpatient costs was also reduced when computed as a cost-effectiveness ratio, although treatment costs continued to remain proportionally higher with inpatient than outpatient treatment.
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Great cormorants diving in cold water: the tricks of the trade. Comp Biochem Physiol A Mol Integr Physiol 1999. [DOI: 10.1016/s1095-6433(99)90085-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
The WD-40 repeat protein FAN binds to a distinct domain of the p55 receptor for tumor necrosis factor (TNF) and signals the activation of neutral sphingomyelinase (N-SMase). To analyze the physiological role of FAN in vivo, we generated FAN-deficient mice by targeted gene disruption. Mice lacking a functional FAN protein do not show any overt phenotypic abnormalities; in particular, the architecture and cellular composition of lymphoid organs appeared to be unaltered. An essential role of FAN in the TNF-induced activation of N-SMase was demonstrated using thymocytes from FAN knockout mice. Activation of extracellular signal-regulated kinases in response to TNF treatment, however, was not impaired by the absence of the FAN protein. FAN-deficient mice show delayed kinetics of recovery after cutaneous barrier disruption suggesting a physiological role of FAN in epidermal barrier repair. Although FAN exhibits striking structural homologies with the CHS/Beige proteins, FAN-deficient mice did not reproduce the phenotype of beige mice.
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[A new method of 3-dimensional imaging of dose distribution in radiotherapy]. RONTGENPRAXIS; ZEITSCHRIFT FUR RADIOLOGISCHE TECHNIK 1999; 51:391-5. [PMID: 9885541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Beside the documentation it is the object of the graphical presentation of dose distribution in radiotherapy to clarify for better judgement. A three-dimensional graphical presentation could rise the understanding. Auto-stereographical presentation of isodoses opens the practicability for a three-dimensional view without the use of additional auxiliarities, such as stereoscope, or spectacles. This is shown by some isodose distribution charts (fixed field-, box-, multiple field- and rotation-technique, AL-treatment).
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Abstract
This article describes the use of drugs and therapeutic techniques in the treatment of ratite diseases. Effective routes of administration are documented. Appropriate selection and dose regimens are provided for bacterial and parasitic conditions. This article includes empirical formularies for antibiotics and anthelmintics. Metabolic drug dosage and nutrient scaling for ratites are outlined.
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Supervisory training for teachers: multiple, long-term effects in an education program for adults with severe disabilities. RESEARCH IN DEVELOPMENTAL DISABILITIES 1998; 19:449-463. [PMID: 9836317 DOI: 10.1016/s0891-4222(98)00017-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We evaluated a means of training special education teachers in supervisory strategies for improving specific teaching-related performances of their paraprofessional, teacher assistants. Using classroom-based instruction and on-the-job monitoring and feedback, seven teachers were trained to systematically observe the data collection and teaching performances of their assistants as well as to provide contingent feedback. The supervisory training for teachers, evaluated using a multiple-probe design across groups of assistants, was accompanied by improvements in data collection performances among seven of eight assistants. Improvement in other teaching skill applications also occurred. The improved performance among the assistants was maintained across a 17-month follow-up period. The supervisory training seemed to have multiple benefits in that the teachers' own teaching-related performances improved once teachers were trained to systematically observe and provide feedback to their assistants. The need for continued research is discussed to evaluate the benefits of supervisory training to improve and maintain other important areas of staff performance.
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[A new parameter for the determination of dose distribution in radiotherapy]. RONTGENPRAXIS; ZEITSCHRIFT FUR RADIOLOGISCHE TECHNIK 1998; 51:218-22. [PMID: 9747126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Expression of epidermal keratins and the cornified envelope protein involucrin is influenced by permeability barrier disruption. J Invest Dermatol 1998; 111:517-23. [PMID: 9740250 DOI: 10.1046/j.1523-1747.1998.00318.x] [Citation(s) in RCA: 99] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In previous studies we have shown that experimental permeability barrier disruption leads to an increase in epidermal lipid and DNA synthesis. Here we investigate whether barrier disruption also influences keratins and cornified envelope proteins as major structural keratinocyte proteins. Cutaneous barrier disruption was achieved in hairless mouse skin by treatments with acetone +/- occlusion, sodium dodecyl sulfate, or tape-stripping. As a chronic model for barrier disruption, we used essential fatty acid deficient mice. Epidermal keratins were determined by one- and two-dimensional gel electrophoresis, immunoblots, and anti-keratin antibodies in biopsy samples. In addition, the expression of the cornified envelope proteins loricrin and involucrin after barrier disruption was determined by specific antibodies in human skin. Acute as well as chronic barrier disruption resulted in the induction of the expression of keratins K6, K16, and K17. Occlusion after acute disruption led to a slight reduction of keratin K6 and K16 expression. Expression of basal keratins K5 and K14 was reduced after both methods of barrier disruption. Suprabasal keratin K10 expression was increased after acute barrier disruption and K1 as well as K10 expression was increased after chronic barrier disruption. Loricrin expression in mouse and in human skin was unchanged after barrier disruption. In contrast, involucrin expression, which was restricted to the granular and upper spinous layers in normal human skin, showed an extension to the lower spinous layers 24 h after acetone treatment. In summary, our results document that acute or chronic barrier disruption leads to expression of keratins K6, K16, and K17 and to a premature expression of involucrin. We suggest that the coordinated regulation of lipid, DNA, keratin, and involucrin synthesis is critical for epidermal permeability barrier function.
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Disseminated coccidioidomycosis in a mandrill baboon (Mandrillus sphinx): a case report. J Zoo Wildl Med 1998; 29:208-13. [PMID: 9732039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
A case of disseminated coccidioidomycosis caused by a dimorphic fungus Coccidioides immitis in a mandrill baboon (Mandrillus sphinx) was diagnosed following radiography, ultrasound-guided aspiration of thoracic lesions, and aspiration cytology of skeletal lesions of the left sixth rib. The diagnosis was confirmed by fungal culture and serum quantitative immunodiffusion for antibodies against C. immitis.
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Hepatotoxicity and secondary photosensitization in a red kangaroo (Megaleia rufus) due to ingestion of Lantana camara. J Zoo Wildl Med 1998; 29:203-7. [PMID: 9732038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Three red kangaroos (Megaleira rufus), an adult male, an adult female, and a yearling, were exposed in bedding and food to coastal bermuda hay that contained the toxic plant Lantana camara. The adult male exhibited signs of anorexia, depression, lethargy, and jaundice. The adult female was presented dead. After 1 wk, following exposure to sunlight, the adult male and a yearling joey developed exudative dermatitis of the ear margins, eyelids, muzzle, and scrotum and opacity of the corneas. The adult male had a leucocytosis, anemia, bilirubinemia, bilirubinuria, hyperproteinemia, and elevated alanine aminotransferase, gamma glutamyl transpeptidase, alkaline phosphatase, and bile acid serum levels. Postmortem examination of the adult male revealed jaundice, and the liver was swollen, mottled, and pale yellow to reddish yellow. The gall bladder was markedly distended. Histopathologically, there was hepatocellular enlargement with vesiculation of the nuclei and sporadic feathery degeneration of the cytoplasm. The yearling joey survived and was treated symptomatically with i.v. fluids and antibiotics. The history, clinical signs, diagnostic findings, necropsy findings, and exposure to the toxic plant Lantana camara support the diagnosis of secondary photosensitization and hepatoxicity.
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Duodenal perforation in a cheetah (Acinonyx jubilatus). J Zoo Wildl Med 1997; 28:481-4. [PMID: 9523644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
An 11-yr-old female cheetah (Acinonyx jubilatus) from a privately owned breeding center for endangered species was referred for evaluation with a history of vomiting and depression of 10 days' duration. After anesthetic induction with tiletamine and zolazepam and anesthetic maintenance with isoflurane, a complete diagnostic workup was performed, including hematology, serum chemistry, and radiography. The clinical diagnosis was septic suppurative inflammation and hemorrhage in the abdomen, consistent with perforation or rupture of the gastrointestinal tract. An exploratory laparotomy showed a perforated duodenal ulcer, which was resected. Subsequent endoscopy revealed no further evidence of ulceration in the upper gastrointestinal tract. Biopsy of the ulcerated tissue collected from the duodenum revealed Gastrospirillum-like organisms. Histologic examination revealed widespread infiltration of lymphocytes and plasma cells into the lamina propria and submucosa. Intraepithelial leukocytes were present along with attenuation, erosion, and ulceration of the superficial epithelium. Fourteen days after surgery, this cheetah was returned to its breeding compound, and no subsequent vomiting has been observed for 4 yr.
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Abstract
The hallmarks of dry skin (xerosis) are scaliness and loss of elasticity. Decreased hydration and a disturbed lipid content of the stratum corneum are also well-known features. The frequency of dry skin increases with ageing. The aim of this study was to examine if these known features of dry skin are related to changes in epidermal proliferation and differentiation. In addition, age-related changes in normal and in dry skin were examined: 62 volunteers were divided by clinical grading and biophysical measurements into groups with young/normal, young/dry, aged/normal and aged/dry skin. Biopsy samples from the lower legs (most severe dryness) were examined by two-dimensional gel electrophoresis and by immunohistochemistry for epidermal proliferation, epidermal keratins and cornified envelope proteins. There was a slight increase in proliferation in both groups with dry skin compared with normal skin of the corresponding age. In aged/normal compared with young/normal skin there was a significant decrease in proliferation. However, epidermal proliferation was the same in aged/dry skin as in young/normal skin. For epidermal differentiation, an age-independent decrease of keratins K1 and K10 and an associated increase in the basal keratins K5 and K14 was detected in dry skin. There was also an age-independent premature expression of the cornified envelope protein involucrin. In contrast, loricrin expression was not influenced by dry skin conditions. In summary, epidermal proliferation was significantly decreased in aged/normal compared with young/normal skin. Dry skin showed significant changes in the epidermal expression of basal and differentiation-related keratins, and a premature expression of involucrin irrespective of age.
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Disposition of single-dose intravenously administered amikacin in emus (Dromaius novaehollandiae). J Zoo Wildl Med 1997; 28:49-54. [PMID: 9226616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The pharmacokinetics of amikacin in emus (Dromaius novaehollandiae) was examined following parenteral administration. A mean 7.2 +/- 0.12 mg/kg dose was administered as a single i.v. bolus, and serum samples were collected at predetermined intervals over a 24-hr period. Amikacin levels were measured using a fluorescence polarization immunoassay, and the resulting concentration-versus-time curve was analyzed using nonlinear regression with least squares parameter estimation. The data were best represented by a three-compartment model with a mean elimination half-life (t1/2 beta) of 0.87 hr, with a longer rate of elimination from the third compartment (t1/2 gamma = 6.06 hr). Mean model-independent parameters obtained were area under the curve (269.66 micrograms.hr/ml), mean residence time (6.48 hr), apparent volume of distribution (0.18 L/kg), and total body drug clearance (0.03 L/hr/kg). Mean serum concentrations exceeded a target peak of 32.0 micrograms/ml and remained above an estimated inhibitory concentration of 8.0 micrograms/ml for approximately 12 hr. Mean serum levels had declined below a target trough of 4 micrograms/ml at 24 hr.
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Amikacin pharmacokinetics and the effects of ambient temperature on the dosage regimen in ball pythons (Python regius). J Zoo Wildl Med 1997; 28:80-8. [PMID: 9226620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The serum concentration of amikacin following intracardiac and i.m. administration of amikacin (3.48 mg/kg) in 12 ball pythons (Python regius) housed at 25 degrees C and 37 degrees C was studied. Blood samples were collected by cardiocentesis at intervals up to 144 hr after administration of amikacin. Drug concentration-versus-time curves following intracardiac administration at both temperatures best fit a two-compartment open model. For snakes housed at 37 degrees C, the extrapolated time 0 concentration (mean +/- SD) was 17.64 +/- 3.5 micrograms/ml with a median elimination half-life of 4.5 days. The maximum concentrations were 11.98 +/- 1.67 micrograms/ml and 13.87 +/- 2.61 micrograms/ml for snakes housed at 25 degrees C and 37 degrees C respectively. There were no significant pharmacokinetic differences among the snakes housed at 25 degrees C and 37 degrees C. Model-independent parameters were area under the curve, 69,900 +/- 0.011 micrograms.min/ml, apparent volume of distribution at steady state, 410 +/- 106 ml/kg, clearance, 0.036 +/- 0.009 ml/min/kg, and mean residence time, 3,530 +/- 273.7 minutes. Mean serum amikacin concentrations did not reach the recommended therapeutic peak concentrations for mammals (25 micrograms/ml). In addition, the amikacin serum concentration did not fall below the recommended therapeutic trough concentrations (2 micrograms/ml) by 6 days. The serum amikacin concentrations were efficacious based on the area under the curve. Therefore, amikacin (3.48 mg/kg) administered i.m. to ball pythons should produce maximum serum concentrations against most pathogenic bacteria. In this study, it would have taken another half-life, or 4.5 days, before trough concentrations of 2 micrograms/ml were achieved. To prevent accumulation, a one-time administration of amikacin may be appropriate.
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Assisting older adults with severe disabilities in expressing leisure preferences: a protocol for determining choice-making skills. RESEARCH IN DEVELOPMENTAL DISABILITIES 1997; 18:113-126. [PMID: 9172280 DOI: 10.1016/s0891-4222(96)00044-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We evaluated a protocol involving two types of choice presentations for assessing leisure choice-making skills of seven older adults with severe disabilities. Initially when presented with pairs of objects representing choices, choice making was validated through demonstration of an object preference. A more complex choice-presentation format was then employed, involving pictures to represent choices. If the preference identified with objects was not demonstrated using pictures, a replication of the object format occurred to ensure changes in choice making using pictures was not due to a preference change. Five participants demonstrated choice-making skills using objects and two demonstrated choices using pictures. These results reflect the importance of assessing choice-making skills prior to presenting choice opportunities. Suggestions for future research focus on expanding the assessment protocol to include a wider array of choice-making skills and training staff to provide choices in a format commensurate with an individual's skill level.
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Pharmacokinetics of a single intravenous enrofloxacin dose in scimitar-horned oryx (Oryx dammah). J Zoo Wildl Med 1997; 28:36-42. [PMID: 9226614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Based on a 1.3 mg/kg mean dosage determined by metabolic energy scaling, enrofloxacin pharmacokinetics of a single i.v. dose of enrofloxacin in five adult scimitar-horned oryx (Oryx dammah) were determined. Drug concentration versus time curves were best fit by residual analysis to a one-compartment open model with a maximum (mean +/- SD) serum concentration after distribution of 1.887 +/- 0.632 micrograms/ml and an elimination half-life of 41.2 +/- 27.5 min. Model-independent parameters were area under the curve (173.63 +/- 147.5 micrograms.min/ml), mean volume of distribution (steady state) (0.80 +/- 0.30 L/kg), clearance (12.07 +/- 7.12 ml/min/kg), and residence time (77.22 +/- 72.8 min). Mean serum enrofloxacin concentrations reached the recommended minimum inhibitory concentration (1.0 micrograms/ml). Drug concentrations remained above the minimum inhibitory concentration of most sensitive bacteria (0.5 micrograms/ml) consistently for 90 min. Based on this study, enrofloxacin would have to be administered parenterally to scimitar-horned oryx at 1.6 mg/kg every 6-8 hr (minimally) to maintain appropriate serum concentrations against susceptible bacteria. The metabolic energy scaled dosed regiment from this study appeared to be too low for the oryx.
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Disposition of single-dose intravenously administered enrofloxacin in emus (Dromaius novaehollandiae). J Zoo Wildl Med 1997; 28:43-8. [PMID: 9226615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The pharmacokinetics of enrofloxacin in emus (Dromaius novaehollandiae) were examined following parenteral administration. A mean allometrically scaled dose of 2.2 +/- 0.03 mg/kg was administered as a single i.v. bolus, and serum samples were collected at predetermined intervals over a 24-hr period. Enrofloxacin levels were measured using high-performance liquid chromatography, and the resulting concentration versus time curve was analyzed using nonlinear regression with least squares parameter estimation. The data were best represented by a two-compartment model with a mean elimination half-life of 3.33 hr. Mean model independent parameters obtained were area under the curve (8.26 micrograms.hr/ml), mean residence time (4.40 hr), apparent volume of distribution (1.49 L/kg), and total body drug clearance (0.36 L/hr/kg). Mean serum concentrations exceeded the target peak of 2.0 micrograms/ml and remained above an estimated inhibitory concentration of 0.5 micrograms/ml for approximately 2 hr. Based upon the results of this study, enrofloxacin administered parenterally to emus at 2.2 mg/kg every 12 hr is expected to achieve therapeutic serum concentrations against susceptible organisms.
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