scholarly journals Y-90 SIRT: evaluation of TCP variation across dosimetric models

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Benjamin J. Van ◽  
Yuni K. Dewaraja ◽  
Mamadou L. Sangogo ◽  
Justin K. Mikell
Keyword(s):  
Standard Model ◽  
Volume Fraction ◽  
Liver Tumors ◽  
Package Insert ◽  
Absorbed Dose ◽  
Tumor Control ◽  
Partition Model ◽  
Pet Ct ◽  
The Standard Model ◽  
Biological Outcomes

Abstract Introduction Much progress has been made in implementing selective internal radiation therapy (SIRT) as a viable treatment option for hepatic malignancies. However, there is still much need for improved options for calculating the amount of activity to be administered. To make advances towards this goal, this study examines the relationship between predicted biological outcomes of liver tumors via tumor control probabilities (TCP) and parenchyma via normal tissue complication probabilities (NTCP) given variations in absorbed dose prescription methodologies. Methods Thirty-nine glass microsphere treatments in 35 patients with hepatocellular carcinoma or metastatic liver disease were analyzed using 99mTc-MAA SPECT/CT and 90Y PET/CT scans. Predicted biological outcomes corresponding to the single compartment (standard) model and multi-compartment (partition) dosimetry model were compared using our previously derived TCP dose-response curves over a range of 80–150 Gy prescribed absorbed dose to the perfused volume, recommended in the package insert for glass microspheres. Retrospective planning dosimetry was performed on the MAA SPECT/CT; changes from the planned infused activity due to selection of absorbed dose level and dosimetry model (standard or partition) were used to scale absorbed doses reported from 90Y PET/CT including liver parenchyma and lesions (N = 120) > 2 ml. A parameterized charting system was developed across all potential prescription options to enable a clear relationship between standard prescription vs. the partition model-based prescription. Using a previously proposed NTCP model, the change in prescribed dose from a standard model prescription of 120 Gy to the perfused volume to a 15% NTCP prescription to the normal liver was explored. Results Average TCP predictions for the partition model compared with the standard model varied from a 13% decrease to a 32% increase when the prescribed dose was varied across the range of 80–150 Gy. In the parametrized chart comparing absorbed dose prescription ranges across the standard model and partition models, a line of equivalent absorbed dose to a tumor was identified. TCP predictions on a per lesion basis varied between a 26% decrease and a 81% increase for the most commonly chosen prescription options when comparing the partition model with the standard model. NTCP model was only applicable to a subset of patients because of the small volume fraction of the liver that was targeted in most cases. Conclusion Our retrospective analysis of patient imaging data shows that the choice of prescribed dose and which model to prescribe potentially contribute to a wide variation in average tumor efficacy. Biological response data should be included as one factor when looking to improve patient care in the clinic. The use of parameterized charting, such as presented here, will help direct physicians when transitioning to newer prescription methods.

scholarly journals Multiscale approach predictions for biological outcomes in ion-beam cancer therapy

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Alexey Verkhovtsev ◽  
Eugene Surdutovich ◽  
Andrey V. Solov’yov
Keyword(s):  
Cancer Therapy ◽  
Ion Beam ◽  
Multiscale Approach ◽  
Biological Outcomes

scholarly journals The Biological Impact of the Human Master Regulator p53 Can Be Altered by Mutations That Change the Spectrum and Expression of Its Target Genes

2006 ◽  
Vol 26 (6) ◽  
pp. 2297-2308 ◽  
Author(s):  
Daniel Menendez ◽  
Alberto Inga ◽  
Michael A. Resnick
Keyword(s):  
Dna Binding ◽  
Target Genes ◽  
Tumor Development ◽  
Human Tumor ◽  
Human Cells ◽  
Binding Domain ◽  
Dna Binding Domain ◽  
Missense Mutations ◽  
The Relationship ◽  
Biological Outcomes

ABSTRACT Human tumor suppressor p53 is a sequence-specific master regulatory transcription factor that targets response elements (REs) in many genes. p53 missense mutations in the DNA-binding domain are often cancer associated. As shown with systems based on the yeast Saccharomyces cerevisiae, p53 mutants can alter the spectra and intensities of transactivation from individual REs. We address directly in human cells the relationship between changes in the p53 master regulatory network and biological outcomes. Expression of integrated, tightly regulated DNA-binding domain p53 mutants resulted in many patterns of apoptosis and survival following UV or ionizing radiation, or spontaneously. These patterns reflected changes in the spectra and activities of target genes, as demonstrated for P21, MDM2, BAX, and MSH2. Thus, as originally proposed for “master genes of diversity,” p53 mutations in human cells can differentially influence target gene transactivation, resulting in a variety of biological consequences which, in turn, might be expected to influence tumor development and therapeutic efficacy.

scholarly journals In vivo Evaluation of Zirconia Abutments in Implant supported Restorations in Partially Edentulous Patients

2017 ◽  
Vol 7 (1) ◽  
pp. 35-42
Author(s):  
Anita Kapri ◽  
Sudhir Joshi
Keyword(s):  
Social Sciences ◽  
Titanium Implants ◽  
P Value ◽  
In Vivo Evaluation ◽  
The Social ◽  
Scale Scores ◽  
Edentulous Patients ◽  
Biological Outcomes

ABSTRACT Dental implants have been a universally accepted option for prosthetic rehabilitation of partially edentulous patients. Titanium implants abutments exhibit a dull grayish hue and give an unnatural appearance. Abutments based on zirconia are one of the alternatives to titanium abutments. To date, few comparative studies have reported on esthetic and biological outcomes of implant-supported restorations with zirconia abutments. Purpose To clinically evaluate the esthetic performance of zirconia abutments in implant-supported restorations. Materials and methods A total of 24 anterior implant sites were chosen for the placement of implants. A delayed loading protocol was followed; 12 zirconia abutments were placed along with 12 titanium abutments in the contralateral sites. Biological and esthetic variables were recorded by a periodontist and prosthodontist. The patients were followed 2 weeks, 1, 3, and 6 months postinsertion. Results All the data for Copenhagen index score and visual analog scale scores were evaluated by the prosthodontist at follow-up appointments; the means were tabulated. The data were statistically analyzed using Statistical Package for the Social Sciences software utilizing paired t-test; p value was found to be significant for all parameters except distal papilla and symmetry, which showed p = 0.257 and p = 0.110 respectively. Conclusion According to the results of this study, esthetic performances of zirconia abutment in implant-supported restorations were determined to be higher than those values associated with titanium abutments. How to cite this article Kapri A, Gupta A, Joshi S. In vivo Evaluation of Zirconia Abutments in Implant supported Restorations in Partially Edentulous Patients. J Contemp Dent 2017;7(1):35-42.

scholarly journals Psychosocial and Biological Outcomes of Immersive, Mindfulness-Based Treks in Nature for Groups of Young Adults and Caregivers Affected by Cancer: Results from a Single Arm Program Evaluation from 2016–2021

2021 ◽  
Vol 18 (23) ◽  
pp. 12622
Author(s):  
David Victorson ◽  
Gretchen Doninger ◽  
Scott Victorson ◽  
Gwen Victorson ◽  
Lars Hall ◽  
...  
Keyword(s):  
Young Adults ◽  
Program Evaluation ◽  
Daily Activities ◽  
Health And Wellbeing ◽  
Short Forms ◽  
Within Subjects ◽  
Educational Career ◽  
Anxiety Depression ◽  
Biological Outcomes ◽  
Improve Health

The COVID-19 pandemic has left many individuals suffering from “connection deficit disorder” given changes to the way we work, go to school, socialize, and engage in daily activities. Young adults affected by cancer between the ages of 18–39 have known this connection deficit long before the pandemic. Being diagnosed and treated for cancer during this time can significantly disrupt engagement in important educational, career, social, and reproductive pursuits, and contribute to increased stress, anxiety, depression, and other negative outcomes. Experiencing meaningful connection—with nature, with peers who understand, and with oneself, may help assuage this adverse effect of disconnect. A single arm within-subjects program evaluation was conducted to examine outcomes following participation in immersive, multi-night, mindfulness-based treks in nature in a sample of young adults (n = 157) and caregivers (n = 50) affected by cancer from 2016–2021. Pre to post-trek changes included significant (p < 0.001) self-reported improvements in feeling connected to nature (d = 0.93–0.95), peers (d = 1.1–1.3), and oneself (d = 0.57–1.5); significant (p < 0.001) improvements on PROMIS Anxiety (d = 0.62–0.78), Depression (d = 0.87–0.89), and Sleep Disturbance (d = 0.37–0.48) short forms; and significant (p < 0.05) changes in pro-inflammatory biomarkers (d = 0.55–0.82). Connection-promoting experiences like this have the potential to improve health and wellbeing in this population and serve as a model for others.

scholarly journals Multiple regulation mechanisms of bacterial quorum sensing

BIOMATH ◽  
2016 ◽  
Vol 5 (1) ◽  
pp. 1607291 ◽  
Author(s):  
Peter Kumberger ◽  
Christina Kuttler ◽  
Peter Czuppon ◽  
Burkhard A. Hense
Keyword(s):  
Quorum Sensing ◽  
Bacterial Species ◽  
Regulatory System ◽  
Interaction Patterns ◽  
Gene Regulatory System ◽  
Bacterial Quorum Sensing ◽  
Regulation Mechanisms ◽  
Bacterial Quorum ◽  
Evolutionary Consequences ◽  
Biological Outcomes

Many bacteria have developed a possibility to recognise aspects of their environment or to communicate with each other by chemical signals. The so-called Quorum sensing (QS) is a special case of this kind of communication. Such an extracellular signalling via small diffusible compounds (called autoinducers) is known for many bacterial species, including pathogenic and beneficial bacteria. Using this mechanism allows them to regulate their behaviour, e.g. virulence. We will focus on the typical QS system of Gram negative bacteria of the so-called lux type, based on a gene regulatory system with a positive feedback loop. There is increasing evidence that autoinducer systems themselves are controlled by various factors, often reflecting the cells’ nutrient or stress state. We model and analyse three possible interaction patterns. Typical aspects are e.g. the range of bistability, the activation threshold and the long term behaviour. Additionally, we aim towards understanding the differences with respect to the biological outcomes and estimating potential ecological or evolutionary consequences, respectively.

scholarly journals Spindle cell melanocytic lesions—part I: an approach to compound naevoidal pattern lesions with spindle cell morphology and Spitzoid pattern lesions

2010 ◽  
Vol 63 (4) ◽  
pp. 296-321 ◽  
Author(s):  
Shachar Sade ◽  
Ayman Al Habeeb ◽  
Danny Ghazarian
Keyword(s):  
Systematic Approach ◽  
Spindle Cell ◽  
Morphological Diversity ◽  
Biological Behaviour ◽  
Full Spectrum ◽  
Algorithmic Approach ◽  
Spindle Cells ◽  
Melanocytic Lesions ◽  
Biological Outcomes ◽  
Approach Problem

Melanocytic lesions show great morphological diversity in their architecture and the cytomorphological appearance of their composite cells. Whereas functional melanocytes reveal a dendritic cytomorphology and territorial isolation, lesional naevomelanocytes and melanoma cells typically show epithelioid, spindled or mixed cytomorphologies and a range of architectural arrangements. Spindling is common to melanocytic lesions, and may be either a characteristic feature or a divergent appearance. The presence of spindle cells may mask the melanocytic nature of a lesion, and is often disconcerting, either because of its infrequent appearance in a particular lesion or its interpretation as a dedifferentiated phenotype. Spindle cell melanocytic lesions follow the full spectrum of potential biological outcomes, and difficulty may be experienced judging the nature of a lesion because of a lack of consistently reliable features to predict biological behaviour. Over time, recognition of numerous histomorphological features that may portend a more aggressive lesion have been identified. However, the translation of these features into a diagnostic entity requires a gestalt approach. Although most spindle cell melanocytic lesions can reliably be resolved with this standard approach, problem areas do exist and cause no end of grief to the surgical pathologist or dermatopathologist. In this review, the authors present their algorithmic approach to spindle cell melanocytic lesions and discuss each entity in turn, in order to (1) model a systematic approach to such lesions, and (2) provide familiarity with those melanocytic lesions that either typically or occasionally display a spindled cytomorphology.

scholarly journals Radiomics: from qualitative to quantitative imaging

2020 ◽  
Vol 93 (1108) ◽  
pp. 20190948 ◽  
Author(s):  
William Rogers ◽  
Sithin Thulasi Seetha ◽  
Turkey A. G. Refaee ◽  
Relinde I. Y. Lieverse ◽  
Renée W. Y. Granzier ◽  
...  
Keyword(s):  
Quantitative Imaging ◽  
Quantitative Information ◽  
Clinical Applications ◽  
Machine Learning Algorithms ◽  
Biological Information ◽  
Imaging Data ◽  
Multistage Process ◽  
Advantages And Disadvantages ◽  
Future Direction ◽  
Biological Outcomes

Historically, medical imaging has been a qualitative or semi-quantitative modality. It is difficult to quantify what can be seen in an image, and to turn it into valuable predictive outcomes. As a result of advances in both computational hardware and machine learning algorithms, computers are making great strides in obtaining quantitative information from imaging and correlating it with outcomes. Radiomics, in its two forms “handcrafted and deep,” is an emerging field that translates medical images into quantitative data to yield biological information and enable radiologic phenotypic profiling for diagnosis, theragnosis, decision support, and monitoring. Handcrafted radiomics is a multistage process in which features based on shape, pixel intensities, and texture are extracted from radiographs. Within this review, we describe the steps: starting with quantitative imaging data, how it can be extracted, how to correlate it with clinical and biological outcomes, resulting in models that can be used to make predictions, such as survival, or for detection and classification used in diagnostics. The application of deep learning, the second arm of radiomics, and its place in the radiomics workflow is discussed, along with its advantages and disadvantages. To better illustrate the technologies being used, we provide real-world clinical applications of radiomics in oncology, showcasing research on the applications of radiomics, as well as covering its limitations and its future direction.

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