The biological effectiveness of intermittent irradiation as a function of overall treatment time: Development of correction factors for linac-based stereotactic radiotherapy

1997 ◽  
Vol 37 (4) ◽  
pp. 765-769 ◽  
Author(s):  
Stanley H. Benedict ◽  
Peck-Sun Lin ◽  
Robert D. Zwicker ◽  
David T. Huang ◽  
Rupert K.A. Schmidt-Ullrich
Keyword(s):  
Stereotactic Radiotherapy ◽  
Treatment Time ◽  
Time Development ◽  
Correction Factors ◽  
Overall Treatment Time ◽  
Biological Effectiveness ◽  
Intermittent Irradiation

scholarly journals Intermolar Mandibular Distraction Osteogenesis—A Preliminary Report

2021 ◽  
Vol 11 (9) ◽  
pp. 4118
Author(s):  
Suen A. N. Lie ◽  
Britt H. B. T. Engelen ◽  
Veronique C. M. L. Timmer ◽  
Nico M. P. Vrijens ◽  
Paolo Asperio ◽  
...  
Keyword(s):  
Distraction Osteogenesis ◽  
Treatment Time ◽  
Average Length ◽  
Case Series ◽  
Growth Spurt ◽  
Overall Treatment Time ◽  
Mandibular Distraction ◽  
Mandibular Distraction Osteogenesis ◽  
Root Fractures

Background: Dental Class II is the most common indication for combined orthodontic-orthognathic treatment. Intermolar mandibular distraction osteogenesis (IMDO) treatment was performed during the growth spurt, to avoid surgery at a later age. The aim of this study is to present our first experience with IMDO. Methods: This is a retrospective case series of patients who underwent an IMDO. All patients showed mandibular retrognathism, and orthodontic treatment with functional appliances was not successful. Results: In total, 20 patients (mean age of 14.8 years (SD = 0.9 ys) were included. All patients achieved a Class I occlusion. An average length gain of 9.6 mm (SD = 3.7 mm) was reached. In one patient an abscess occurred. Nine patients presented with root fractures of the second molar; three were lost, one treated endodontically. The average time between insertion and removal of the distractors was 4.6 months (SD = 1.5 mths). In one case a premature consolidation was seen. Conclusion: We achieved satisfactory results with IMDO, although undesirable effects occurred. An advantage is the manageable overall treatment time. Open questions concern the occurrence of root fractures. Furthermore, the question of long-term stability is open. The question of dynamic distraction treatment in relation to temporomandibular joint changes can only be answered in the long term.

Primary Human Liver Cells as Source for Modular Extracorporeal Liver Support - a Preliminary Report

2002 ◽  
Vol 25 (10) ◽  
pp. 1001-1005 ◽  
Author(s):  
I.M. Sauer ◽  
K. Zeilinger ◽  
N. Obermayer ◽  
G. Pless ◽  
A. Grünwald ◽  
...  
Keyword(s):  
Human Liver ◽  
Treatment Time ◽  
Liver Perfusion ◽  
Cell Mass ◽  
Liver Weight ◽  
Liver Cells ◽  
Liver Support ◽  
Overall Treatment Time ◽  
Human Liver Cells ◽  
Extracorporeal Liver Support

Cell-based extracorporeal liver support is an option to assist or replace the failing organ until regeneration or until transplantation can be performed. The use of porcine cells or tumor cell lines is controversial. Primary human liver cells, obtained from explanted organs found to be unsuitable for transplantation, are a desirable cell source as they perform human metabolism and regulation. The Modular Extracorporeal Liver Support (MELS) concept combines different extracorporeal therapy units, tailored to suit the individual and intra-individual clinical needs of the patient. A multi-compartment bioreactor (CellModule) is loaded with human liver cells obtained by 5-step collagenase liver perfusion. A cell mass of 400 g – 600 g enables the clinical application of a liver lobe equivalent hybrid organ. A detoxification module enables single pass albumin-dialysis via a standard high-flux dialysis filter, and continuous venovenuous hemodiafiltration may be included if required. Cells from 54 human livers have been isolated (donor age: 56 ± 13 years, liver weight: 1862 ± 556 g resulting in a viability of 55.0 ± 15.9%). These grafts were not suitable for LTx, due to steatosis (54%), cirrhosis (15%), fibrosis (9%), and other reasons (22%). Out of 36 prepared bioreactors, 10 were clinically used to treat 8 patients with liver failure. The overall treatment time was 7–144 hours. No adverse events were observed. Initial clinical applications of the bioreactor evidenced the technical feasibility and safety of the system.

scholarly journals Orthodontic treatment of a particular subgroup of children with special health care needs, children with craniofacial anomalies: An analysis of treatment length and clinical outcome

2015 ◽  
Vol 86 (1) ◽  
pp. 115-120 ◽  
Author(s):  
Marco Taddei ◽  
Giovanni D'Alessandro ◽  
Franco Amunni ◽  
Gabriela Piana
Keyword(s):  
Orthodontic Treatment ◽  
Treatment Time ◽  
Special Health Care Needs ◽  
Craniofacial Anomalies ◽  
Health Care Needs ◽  
Care Needs ◽  
Overall Treatment Time ◽  
Special Health Care ◽  
Treatment Start ◽  
Special Health

ABSTRACT Objective:  To analyze any differences in the orthodontic treatment between children belonging to a particular subgroup of subjects with special health care needs (SHCN), children with craniofacial anomalies (CFA), and children not diagnosed with SHCN (NO SHCN). Materials and Methods:  The study sample consisted of 50 children with SHCN and a confirmed diagnosis of CFA (SHCN/CFA); the control group consisted of 50 NO SHCN children fully matched for age, gender, and type of appliance used. The differences between the two groups were analyzed retrospectively: pre-, posttreatment scores, and score reduction of the Peer Assessment Rating Index (PAR), dental health component (DHC), and aesthetic component (AC) of Orthodontic Treatment Need Index (IOTN), number of appointments, number of simple or complex chair-time appointments, overall treatment time, and age at treatment start and end. Results:  There were no statistically significant differences between the SHCN/CFA and NO SHCN groups for number of appointments, overall treatment time, age at treatment start, and age at treatment end (P  =  .682, .458, .535, and .675, respectively). There were statistically significant differences between groups in PAR, DHC, AC pre- and posttreatment, and number of simple and complex chair-time appointments (P  =  .030 and .000; .020 and .023; .000 and .000; .043; and .037; respectively). The reduction of PAR, DHC, and AC scores was not significantly different between groups (P  =  .060, .765, and .825, respectively). Conclusion:  The treatment of children with SHCN, in general, and with CFA, in particular, on the one hand involves a higher rate of using complex chair time appointments and an inferior treatment outcome, by the other side implies an overall treatment time and a reduction of PAR, DHC or AC scores similar to the treatment of children not diagnosed with SHCN.

Altered Fractionation Schedules in Radiotherapy of Head and Neck Cancer. A Review

1992 ◽  
Vol 78 (5) ◽  
pp. 311-325 ◽  
Author(s):  
Carlo Fallai ◽  
Patrizia Olmi
Keyword(s):  
Total Dose ◽  
Head And Neck ◽  
Local Control ◽  
Randomized Trials ◽  
Treatment Time ◽  
Dose Intensity ◽  
Field Size ◽  
Overall Treatment Time ◽  
Altered Fractionation ◽  
Improvement In Survival

The authors review the main contributions of international literature to show the current status in clinical trials on unconventional fractionations of the dose in radiotherapy of head and neck cancers. Several clinical (but only a few randomized) trials have been conducted over the last 15 years using hyperfractionated (HF), accelerated (AF) or mixed (HF-AF) schedules. HF schedules have obtained promising results in terms of local control in comparison with conventional fractionation (CF) of the dose. Improvement in survival was also obtained by the random trials of Pinto and Sanchiz, whereas in EORTC trial no. 22791, the improvement in survival rate was only marginal. A significant increase in local control and, less frequently, in survival has been claimed in several studies using HF-AF. Such data still need to be confirmed by a random study, since EORTC trial 22811 showed superimposable results in comparison with CF. Selection of the most suitable cases for altered fractionation schemes is also being studied in ongoing trials of the EORTC (22851) and RTOG (90-03). As regards acute reactions during and after altered fractionation, they are more severe than after CF. Only pure HF with a dose intensity approximately comparable to CF seems to produce similar acute reactions. Several factors have been found to influence the severity of acute mucosal reactions: interfraction interval, overall treatment time, total dose, and field size. As regards late damage, genuine HF schemes seem to cause roughly equivalent late damage in comparison to CF, whereas high-dose intensity schedules have a higher rate of complications. Interfraction interval, overall treatment time, total dose, fraction size and field size can influence the risk of late sequelae. Before altered fractionations can be considered standard therapy, more data are needed, which should be provided by multicentric randomized trials, some of which are already in progress.

scholarly journals PPARs in Irradiation-Induced Gastrointestinal Toxicity

PPAR Research ◽  
2010 ◽  
Vol 2010 ◽  
pp. 1-12 ◽  
Author(s):  
Christine Linard ◽  
Maâmar Souidi
Keyword(s):  
Normal Tissue ◽  
Treatment Time ◽  
Therapeutic Benefit ◽  
Gastrointestinal Toxicity ◽  
Overall Treatment Time ◽  
Inflammatory Reactions ◽  
Normal Tissues ◽  
Inflammatory Processes ◽  
Patients Experience ◽  
Abdominal Irradiation

The use of radiation therapy to treat cancer inevitably involves exposure of normal tissues. Although the benefits of this treatment are well established, many patients experience distressing complications due to injury to normal tissue. These side effects are related to inflammatory processes, and they decrease therapeutic benefit by increasing the overall treatment time. Emerging evidence indicates that PPARs and their ligands are important in the modulation of immune and inflammatory reactions. This paper discusses the effects of abdominal irradiation on PPARs, their role and functions in irradiation toxicity, and the possibility of using their ligands for radioprotection.

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