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2.
Nat Neurosci ; 26(11): 1868-1879, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37798411

ABSTRACT

The amygdala processes positive and negative valence and contributes to addiction, but the cell-type-specific gene regulatory programs involved are unknown. We generated an atlas of single-nucleus gene expression and chromatin accessibility in the amygdala of outbred rats with high and low cocaine addiction-like behaviors following prolonged abstinence. Differentially expressed genes between the high and low groups were enriched for energy metabolism across cell types. Rats with high addiction index (AI) showed increased relapse-like behaviors and GABAergic transmission in the amygdala. Both phenotypes were reversed by pharmacological inhibition of the glyoxalase 1 enzyme, which metabolizes methylglyoxal-a GABAA receptor agonist produced by glycolysis. Differences in chromatin accessibility between high and low AI rats implicated pioneer transcription factors in the basic helix-loop-helix, FOX, SOX and activator protein 1 families. We observed opposite regulation of chromatin accessibility across many cell types. Most notably, excitatory neurons had greater accessibility in high AI rats and inhibitory neurons had greater accessibility in low AI rats.


Subject(s)
Cocaine-Related Disorders , Cocaine , Humans , Rats , Animals , Amygdala/physiology , Neurons , Chromatin/metabolism , Cocaine/pharmacology
3.
J Vis Commun Med ; 46(3): 133-142, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37746710

ABSTRACT

Multimodal communication via social media employed by governments as a COVID-19 communication strategy with multilingual populations hopes to alter behaviours and attitudes. However, there is presently no understanding about the responsiveness of these videos to the needs of culturally and linguistically diverse (CaLD) populations in Australia. This study aimed to analyse the cultural responsiveness of content in multilingual videos shared via a government social media page from NSW, Australia. A systematic search of videos shared between June 2021 and October 2021 was conducted. Using quantitative methods, 37 videos were analysed using a modified version of the Patient-oriented and culturally-adapted (POCA) healthcare translation model and readability indexes. Of these, 5/37 were classified as culturally responsive. The culturally responsive videos scored higher than those that were not culturally responsive. While credible sources, positive language and cultural symbols were observed in several of the videos, there was a lack of familiar experiences and economically viable vaccine uptake behaviours. Videos favoured generic examples of vaccine practices and failed to address concerns about vaccine eligibility, cost, and transport. All videos exceeded recommended readability indices for CaLD populations. Removing complex and abstract terminology and including familiar vaccine experiences could improve multilingual communication for CaLD communities.


Subject(s)
COVID-19 , Social Media , Humans , COVID-19 Vaccines , Cultural Diversity , COVID-19/epidemiology , COVID-19/prevention & control , Australia , Vaccination
5.
bioRxiv ; 2023 Apr 27.
Article in English | MEDLINE | ID: mdl-37163096

ABSTRACT

A single gene may be regulated by multiple enhancers, but how they work in concert to regulate transcription is poorly understood. Prior studies have mostly examined enhancers at single loci and have reached inconsistent conclusions about whether epistatic-like interactions exist between them. To analyze enhancer interactions throughout the genome, we developed a statistical framework for CRISPR regulatory screens that utilizes negative binomial generalized linear models that account for variable guide RNA (gRNA) efficiency. We reanalyzed a single-cell CRISPR interference experiment that delivered random combinations of enhancer-targeting gRNAs to each cell and interrogated interactions between 3,808 enhancer pairs. We found that enhancers act multiplicatively with one another to control gene expression, but our analysis provides no evidence for interaction effects between pairs of enhancers regulating the same gene. Our findings illuminate the regulatory behavior of multiple enhancers and our statistical framework provides utility for future analyses studying interactions between enhancers.

6.
Genome Biol ; 24(1): 96, 2023 04 26.
Article in English | MEDLINE | ID: mdl-37101218

ABSTRACT

BACKGROUND: The microrchidia (MORC) proteins are a family of evolutionarily conserved GHKL-type ATPases involved in chromatin compaction and gene silencing. Arabidopsis MORC proteins act in the RNA-directed DNA methylation (RdDM) pathway, where they act as molecular tethers to ensure the efficient establishment of RdDM and de novo gene silencing. However, MORC proteins also have RdDM-independent functions although their underlying mechanisms are unknown. RESULTS: In this study, we examine MORC binding regions where RdDM does not occur in order to shed light on the RdDM-independent functions of MORC proteins. We find that MORC proteins compact chromatin and reduce DNA accessibility to transcription factors, thereby repressing gene expression. We also find that MORC-mediated repression of gene expression is particularly important under conditions of stress. MORC-regulated transcription factors can in some cases regulate their own transcription, resulting in feedback loops. CONCLUSIONS: Our findings provide insights into the molecular mechanisms of MORC-mediated chromatin compaction and transcription regulation.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Chromatin/metabolism , Arabidopsis/genetics , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Gene Silencing , Transcription Factors/metabolism , DNA Methylation , Gene Expression Regulation, Plant
7.
Nat Plants ; 9(3): 460-472, 2023 03.
Article in English | MEDLINE | ID: mdl-36879017

ABSTRACT

DNA methylation has been utilized for target gene silencing in plants. However, it is not well understood whether other silencing pathways can be also used to manipulate gene expression. Here we performed a gain-of-function screen for proteins that could silence a target gene when fused to an artificial zinc finger. We uncovered many proteins that suppressed gene expression through DNA methylation, histone H3K27me3 deposition, H3K4me3 demethylation, histone deacetylation, inhibition of RNA polymerase II transcription elongation or Ser-5 dephosphorylation. These proteins also silenced many other genes with different efficacies, and a machine learning model could accurately predict the efficacy of each silencer on the basis of various chromatin features of the target loci. Furthermore, some proteins were also able to target gene silencing when used in a dCas9-SunTag system. These results provide a more comprehensive understanding of epigenetic regulatory pathways in plants and provide an armament of tools for targeted gene manipulation.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Histones/metabolism , Arabidopsis/genetics , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Gene Silencing , Gene Expression , Gene Expression Regulation, Plant
8.
Nat Commun ; 14(1): 1736, 2023 03 28.
Article in English | MEDLINE | ID: mdl-36977663

ABSTRACT

Arabidopsis telomeric repeat binding factors (TRBs) can bind telomeric DNA sequences to protect telomeres from degradation. TRBs can also recruit Polycomb Repressive Complex 2 (PRC2) to deposit tri-methylation of H3 lysine 27 (H3K27me3) over certain target loci. Here, we demonstrate that TRBs also associate and colocalize with JUMONJI14 (JMJ14) and trigger H3K4me3 demethylation at some loci. The trb1/2/3 triple mutant and the jmj14-1 mutant show an increased level of H3K4me3 over TRB and JMJ14 binding sites, resulting in up-regulation of their target genes. Furthermore, tethering TRBs to the promoter region of genes with an artificial zinc finger (TRB-ZF) successfully triggers target gene silencing, as well as H3K27me3 deposition, and H3K4me3 removal. Interestingly, JMJ14 is predominantly recruited to ZF off-target sites with low levels of H3K4me3, which is accompanied with TRB-ZFs triggered H3K4me3 removal at these loci. These results suggest that TRB proteins coordinate PRC2 and JMJ14 activities to repress target genes via H3K27me3 deposition and H3K4me3 removal.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Histones/genetics , Histones/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Arabidopsis/genetics , Arabidopsis/metabolism , Polycomb Repressive Complex 2/genetics , Polycomb Repressive Complex 2/metabolism , Telomere-Binding Proteins/metabolism , Demethylation , Gene Expression Regulation, Plant , Polycomb-Group Proteins/genetics , Polycomb-Group Proteins/metabolism , Jumonji Domain-Containing Histone Demethylases/genetics , Jumonji Domain-Containing Histone Demethylases/metabolism
9.
Health Psychol Res ; 11: 70165, 2023.
Article in English | MEDLINE | ID: mdl-36844644

ABSTRACT

Koro syndrome is a multi-tiered disease presenting as an overwhelming belief that one's sex organs are shrinking into their body. Moderate to severe anxiety attacks are associated with the condition, along with a fear of imminent death. Koro is often culturally related and is most seen as an epidemic form in East and Southeast Asia, although it can present anywhere worldwide in its sporadic form. The condition typically affects young males who believe in sex-related myths, and many individuals can co-present with anxiety, depression, or even psychosis. Although most presentations of Koro are self-limiting, the condition is harmful for one's self-esteem and quality of life, and some individuals may go through extreme, physically injurious measures to prevent genital retraction. Treatments include the use of psychotherapy that has a sex education component, especially if the patient believes in culturally rooted myths. In sporadic Koro, it is believed that if the primary psychiatric disorder is treated with anxiolytics, antidepressants, sedatives, or psychotics, the secondary Koro-like symptoms will also fade. Additional investigation on the prevalence, pathogenesis, factors that correlate with treatment efficacy are needed to fully understand Koro syndrome.

10.
Health Psychol Res ; 10(3): 38247, 2022.
Article in English | MEDLINE | ID: mdl-36118982

ABSTRACT

Ketamine is a common medical anesthetic and analgesic but is becoming more widely used as a recreational drug. Significant side effects on the urinary tract are associated with frequent recreational ketamine use most notably ketamine-induced cystitis (KIC). Regular ketamine consumption has been shown to increase the risk of cystitis symptoms by 3- to 4-fold, and cessation of ketamine use is usually associated with improvement of symptoms. Common KIC-related problems are urinary pain and discomfort, bladder epithelial barrier damage, reduced bladder storage and increased pressure, ureter stenosis, and kidney failure, all of which significantly impact patients' quality of life. Furthermore, it becomes a vicious cycle when KIC patients attempt to manage their urinary pain with increased ketamine use. The precise pathophysiology of KIC is still unknown but several theories exist, most of which highlight the inflammatory signaling pathways leading to bladder epithelium damage due to presence of ketamine in the urine. Empirical treatment options for KIC are available and consist of ketamine cessation, noninvasive therapies, and surgery, and should be decided upon based on the time course and severity of the disease. Of note, cessation of use is strongly recommended for all KIC patients, and should be supplemented with motivational interviews and psychological and social support. It is crucial for clinicians to be familiar with KIC diagnosis and treatment, and to be prepared to have informed discussions with ketamine-using patients about the potential health consequences of ketamine.

11.
Health Psychol Res ; 10(3): 38243, 2022.
Article in English | MEDLINE | ID: mdl-36118983

ABSTRACT

Urologic procedures (both open and minimally invasive) can cause pain due to the surgery itself, devices placed, and post-operative issues. Thus, pain management is important for every post-procedure recovery period. Opioid use post-surgery is common and often over-prescribed contributing to persistent use by patients. In this article, we review the extent of opioid use in pediatric urologic procedures, vasectomy, endourologic procedures, penile implantation, urogynecologic procedures, prostatectomy, nephrectomy, cystectomy, and scrotal/testicular cancer surgery. Generally, we have found that institutions do not have a standardized protocol with a set regimen to prescribe opioids, resulting in more opioids being prescribed than needed and patients not properly disposing of their unused prescriptions. However, many institutions recognize their opioid overuse and are implementing new multimodal opioid-sparing analgesics methods such as non-opioid peri-operative medications, minimally invasive robotic surgery, and nerve blocks or local anesthetics with varying degrees of success. By shedding light on these opioid-free methods and prescription protocols, along with improved patient education and counselling, we hope to bring awareness to institutions and decrease unnecessary opioid use.

12.
Nat Cell Biol ; 19(9): 1017-1026, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28812580

ABSTRACT

Although normally dormant, hair follicle stem cells (HFSCs) quickly become activated to divide during a new hair cycle. The quiescence of HFSCs is known to be regulated by a number of intrinsic and extrinsic mechanisms. Here we provide several lines of evidence to demonstrate that HFSCs utilize glycolytic metabolism and produce significantly more lactate than other cells in the epidermis. Furthermore, lactate generation appears to be critical for the activation of HFSCs as deletion of lactate dehydrogenase (Ldha) prevented their activation. Conversely, genetically promoting lactate production in HFSCs through mitochondrial pyruvate carrier 1 (Mpc1) deletion accelerated their activation and the hair cycle. Finally, we identify small molecules that increase lactate production by stimulating Myc levels or inhibiting Mpc1 carrier activity and can topically induce the hair cycle. These data suggest that HFSCs maintain a metabolic state that allows them to remain dormant and yet quickly respond to appropriate proliferative stimuli.


Subject(s)
Cell Proliferation , Cellular Senescence , Glycolysis , Hair Follicle/enzymology , L-Lactate Dehydrogenase/metabolism , Lactic Acid/metabolism , Stem Cells/enzymology , Acrylates/pharmacology , Animals , Anion Transport Proteins/antagonists & inhibitors , Anion Transport Proteins/genetics , Anion Transport Proteins/metabolism , Cell Proliferation/drug effects , Cellular Senescence/drug effects , Female , Genotype , Glycolysis/drug effects , Hair Follicle/cytology , Hair Follicle/drug effects , Isoenzymes/deficiency , Isoenzymes/genetics , Isoenzymes/metabolism , L-Lactate Dehydrogenase/deficiency , L-Lactate Dehydrogenase/genetics , Lactate Dehydrogenase 5 , Male , Mice, Inbred C57BL , Mice, Knockout , Mitochondrial Membrane Transport Proteins/antagonists & inhibitors , Mitochondrial Membrane Transport Proteins/genetics , Mitochondrial Membrane Transport Proteins/metabolism , Monocarboxylic Acid Transporters , Phenotype , Proto-Oncogene Proteins c-myc/metabolism , Signal Transduction , Stem Cells/drug effects , Time Factors
13.
Am J Clin Oncol ; 40(5): 517-522, 2017 Oct.
Article in English | MEDLINE | ID: mdl-26165418

ABSTRACT

OBJECTIVES: Definitive chemoradiotherapy for unresectable pancreatic cancer has traditionally involved 5-fluorouracil-based chemotherapy. Our institution has a long history of combining gemcitabine and radiotherapy (RT), and performed a retrospective review of all patients treated in this manner. MATERIALS AND METHODS: We reviewed the records of 180 patients treated from 1999 to 2012. Mean RT dose was 40.9 Gy in 2.2-Gy fractions, and targeted only radiographically apparent disease. Ninety-six percent of patients received full-dose gemcitabine-based chemotherapy with RT. Kaplan-Meier was used to analyze time-to-event endpoints, and Cox regression models were used to assess significant prognostic variables. RESULTS: Eighty-nine percent of patients completed RT without a toxicity-related treatment break. Median follow-up was 10.2 months. Twenty-nine percent of patients had a radiographic decrease in primary tumor size following treatment. Median overall survival was 11.8 months, time to distant metastasis (TDM) was 6.7 months, and time to local recurrence (TLR) was 8.3 months. On multivariate analysis, male sex, lower performance status, and higher posttreatment CA 19-9 level predicted for worse overall survival. Posttreatment, CA 19-9 was also associated with TDM and TLR, and radiographic tumor response was associated with better TLR. CONCLUSION: Definitive chemoradiation using full-dose gemcitabine is well tolerated and achieves survival outcomes comparable to reported trials in the literature.


Subject(s)
Chemoradiotherapy/methods , Deoxycytidine/analogs & derivatives , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/radiotherapy , Adult , Aged , Antimetabolites, Antineoplastic/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Deoxycytidine/administration & dosage , Female , Humans , Male , Middle Aged , Pancreatic Neoplasms/mortality , Pancreatic Neoplasms/pathology , Radiotherapy/methods , Radiotherapy Dosage , Survival Rate , Treatment Outcome , Gemcitabine
14.
J Lab Autom ; 21(4): 548-56, 2016 Aug.
Article in English | MEDLINE | ID: mdl-26882924

ABSTRACT

Introducing functional macromolecules into a variety of living cells is challenging but important for biology research and cell-based therapies. We report a novel cell delivery platform based on rotating shape anisotropic magnetic particles (SAMPs), which make very small cuts on cell membranes for macromolecule delivery with high efficiency and high survivability. SAMP delivery is performed by placing commercially available nickel powder onto cells grown in standard cell culture dishes. Application of a uniform magnetic field causes the magnetic particles to rotate because of mechanical torques induced by shape anisotropic magnetization. Cells touching these rotating particles are nicked, which generates transient membrane pores that enable the delivery of macromolecules into the cytosol of cells. Calcein dye, 3 and 40 kDa dextran polymers, a green fluorescence protein (GFP) plasmid, siRNA, and an enzyme (ß-lactamase) were successfully delivered into HeLa cells, primary normal human dermal fibroblasts (NHDFs), and mouse cortical neurons that can be difficult to transfect. The SAMP approach offers several advantages, including easy implementation, low cost, high throughput, and efficient delivery of a broad range of macromolecules. Collectively, SAMP delivery has great potential for a broad range of academic and industrial applications.


Subject(s)
Cell Membrane/metabolism , Drug Delivery Systems/methods , Macromolecular Substances/metabolism , Magnetics/methods , Animals , Cells, Cultured , Genetic Therapy/methods , Humans , Mice , Transfection/methods
15.
Head Neck ; 38 Suppl 1: E1086-96, 2016 04.
Article in English | MEDLINE | ID: mdl-26445898

ABSTRACT

BACKGROUND: Concurrent chemoradiotherapy (concurrent CRT) to treat head and neck cancer is associated with significant reductions of weight, mobility, and quality of life (QOL). An intervention focusing on functional exercise may attenuate these losses. METHODS: We allocated patients to a 14-week functional resistance and walking program designed to maintain physical activity during cancer treatment (MPACT group; n = 11), or to usual care (control group; n = 9). Outcomes were assessed at baseline, and 7 and 14 weeks. RESULTS: Compared to controls, the MPACT participants had attenuated decline or improvement in several strength, mobility, physical activity, diet, and QOL endpoints. These trends were statistically significant (p < .05) in knee strength, mental health, head and neck QOL, and barriers to exercise. CONCLUSION: In this pilot study of patients with head and neck cancer undergoing concurrent CRT, MPACT training was feasible and maintained or improved function and QOL, thereby providing the basis for larger future interventions with longer follow-up. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1086-E1096, 2016.


Subject(s)
Exercise , Head and Neck Neoplasms/therapy , Quality of Life , Chemoradiotherapy , Female , Humans , Male , Middle Aged , Pilot Projects , Resistance Training , Walking
16.
J Card Fail ; 21(5): 419-425, 2015 May.
Article in English | MEDLINE | ID: mdl-25704104

ABSTRACT

BACKGROUND: Stress-induced cardiomyopathy (SCM) is a reversible cardiomyopathy observed in patients without significant coronary disease. The aim of this study was to assess the incidence and clinical significance of right ventricular (RV) involvement in SCM. METHODS AND RESULTS: We retrospectively analyzed echocardiograms from 40 consecutive patients who presented with SCM at Stanford University Medical Center from September 2000 to November 2010. The primary end point was overall mortality. RV involvement was observed in 20 patients (50%; global RV hypokinesia in 15 patients and focal RV apical akinesia in 5 patients). The independent correlates of RV involvement were older age (odds ratio [OR] 1.09, 95% confidence interval [CI] 1.02-1.7two, P = .01) and LVEF (per 10% decrease: OR 3.60, CI 1.77-7.32; P = .02). At a mean follow-up of 44 ± 32 months, 12 patients (30%) died (in-hospital death in 3 patients). At multivariate analysis, the presence of an RV fractional area change <35% emerged as an independent predictor of death (OR 3.6, CI 1.06-12.41; P = .04). CONCLUSIONS: RV involvement is a common finding in SCM, and may present as either global or focal RV apical involvement. Both older age and lower LVEF are associated with a higher risk of RV involvement, which appears to be a major predictor of death.


Subject(s)
Takotsubo Cardiomyopathy/diagnosis , Takotsubo Cardiomyopathy/epidemiology , Ventricular Dysfunction, Right/diagnosis , Ventricular Dysfunction, Right/epidemiology , Aged , Aged, 80 and over , Cohort Studies , Female , Humans , Male , Middle Aged , Prevalence , Prognosis , Retrospective Studies , Stroke Volume/physiology , Takotsubo Cardiomyopathy/physiopathology , Ventricular Dysfunction, Right/physiopathology
17.
Am J Clin Oncol ; 38(4): 411-4, 2015 Aug.
Article in English | MEDLINE | ID: mdl-24762708

ABSTRACT

There is a systematic relationship between fatigue, sleep, and decreased quality of life in cancer patients, with notably poor sleep quality among many head and neck cancer patients during and after treatment. An often overlooked cause of sleep disturbance in this patient population is obstructive sleep apnea (OSA). This review explores the current literature on the prevalence and clinical correlates of OSA, management outcomes, and data on cytokine-mediated fatigue in OSA. OSA appears to be prevalent in head and neck cancer patients, both at baseline and after treatment, especially with multimodality therapy including radiation therapy. Predictors of developing OSA include larger tumor size and hypopharynx or larynx primary site. There is evidence that the level of fatigue seen in these patients is not necessarily correlated with the severity of their OSA. Current research highlights the role of proinflammatory cytokines, which can also be synergistically activated by radiation therapy, as mediators of fatigue. Primary management of OSA consists of continuous positive airway pressure. Although continuous positive airway pressure has been shown to improve clinical symptoms, compliance with its use remains a problem and will be an area of future research.


Subject(s)
Fatigue/physiopathology , Head and Neck Neoplasms/pathology , Sleep Apnea, Obstructive/physiopathology , Cytokines/immunology , Fatigue/etiology , Fatigue/immunology , Head and Neck Neoplasms/complications , Head and Neck Neoplasms/therapy , Humans , Otorhinolaryngologic Surgical Procedures/adverse effects , Radiotherapy/adverse effects , Sleep Apnea, Obstructive/etiology , Tumor Burden
18.
Pract Radiat Oncol ; 4(2): 99-107, 2014.
Article in English | MEDLINE | ID: mdl-24890350

ABSTRACT

PURPOSE: Little is known regarding the prognostic capability of prostate-specific antigen (PSA) nadir (nPSA) and time to nPSA (TnPSA) following salvage radiation therapy (SRT) for biochemical failure (BF) postradical prostatectomy (RP). We sought to assess their prognostic significance in this setting. METHODS AND MATERIALS: A total of 448 patients who received SRT without androgen deprivation therapy at a single academic institution were included in this retrospective analysis. Univariate analysis and multivariate Cox proportional hazards models were used to assess BF, distant metastasis (DM), prostate cancer-specific death (PCSD), and overall survival (OS). A prognostic nomogram incorporating nPSA and TnPSA was developed and validated in randomly allocated training and validation cohorts. RESULTS: Median follow-up post-SRT was 64 months. Median nPSA and TnPSA were undetectable and 6.7 months, respectively. On univariate analysis, a detectable nPSA (P < .01) and TnPSA <6 months (P < .01) were predictive of all outcomes. In a training cohort, a 14-point nomogram incorporating detectable nPSA, TnPSA, Gleason score, pre-radiation therapy PSA, and seminal vesicle invasion predicted BF (hazard ratio[HR], 1.4; P < .0001), DM (HR, 1.3; P < .0001), PCSD (HR, 1.3; P < .0001), and decreased OS (HR, 1.2; P < .0001). Adding nPSA and TnPSA improved the prognostic value of the nomogram compared to using clinical predictors only. The nomogram was evaluated in a validation cohort where it was predictive of BF (c-index = 0.77), DM (0.73), and PCSD (0.69). CONCLUSIONS: Patients with a detectable nPSA also having a TnPSA <6 months post-SRT are at high-risk for DM, PCSD, and decreased OS. These patients are unlikely to have clinically localized disease and should be considered for initiation of systemic therapies.


Subject(s)
Prostate-Specific Antigen/blood , Prostatic Neoplasms/blood , Prostatic Neoplasms/radiotherapy , Salvage Therapy/methods , Aged , Analysis of Variance , Humans , Male , Middle Aged , Prostatectomy , Prostatic Neoplasms/pathology , Reproducibility of Results , Retrospective Studies , Risk Factors , Survival Analysis
19.
Pract Radiat Oncol ; 4(1): 20-6, 2014.
Article in English | MEDLINE | ID: mdl-24621419

ABSTRACT

PURPOSE: Adjuvant high-dose-rate vaginal brachytherapy (VB) is commonly used in endometrial cancer. We evaluated the dosimetric and cost differences of using either a single plan or replan prior to each fraction for single- and multi-channel VB. METHODS AND MATERIALS: We evaluated 84 fractions from 25 patients at our institution (16 single-channel patients each 3 fractions; 9 multi-channel patients each 4 fractions). All fractions were preceded by a computed tomographic (CT) simulation scan, after which a unique treatment plan was generated, dose points per International Commission on Radiation Units and Measurements (ICRU) 38. We calculated the dose to critical organs based on a decay-and-treat method utilizing the original catheter dwell-times for the initial fraction, and also the interfractional motion of the critical organ points between the initial and the subsequent CT scans. RESULTS: The absolute mean dose difference was 14 cGy for bladder and 15 cGy for rectum between the replan and decay methods for single-channel, and 14 cGy for both organ points for the multi-channel cylinder. The bladder and rectum doses were not found to be significantly different between the replan and decay methods for either single-channel (bladder, P = .08; rectum, P = .19) or multi-channel cylinders (bladder, P = .85; rectum, P = .10). The mean interfractional displacement of the organ points between the initial and subsequent CT scans was 1.10 cm for the bladder and 0.67 cm for the rectum for single-channel, and 0.87 cm and 0.51 cm for multi-channel cylinders. The maximum interfractional motion was seen in the transverse plane for both organ points for both types of cylinders. At our institution, the decay method was 19% and 22% more cost-effective for single-channel and multi-channel cylinders, respectively. CONCLUSIONS: Our data show no dosimetric advantage, but higher costs, associated with replanning prior to each fraction for both single- and multi-channel VB. Fractional replanning should not be utilized on a routine basis.


Subject(s)
Brachytherapy/methods , Endometrial Neoplasms/radiotherapy , Radiotherapy Planning, Computer-Assisted/methods , Dose-Response Relationship, Radiation , Endometrial Neoplasms/pathology , Female , Humans , Radiometry , Radiotherapy Dosage , Rectum/anatomy & histology , Rectum/radiation effects , Urinary Bladder/anatomy & histology , Urinary Bladder/radiation effects , Vagina
20.
J Appl Clin Med Phys ; 15(1): 4520, 2014 Jan 06.
Article in English | MEDLINE | ID: mdl-24423851

ABSTRACT

Primary peritoneal clear cell carcinoma (PP-CCC), which is a rare tumor with poor prognosis, is typically managed with surgery and/or chemotherapy. We present a unique treatment approach for a patient with a pelvic PP-CCC, consisting of postchemotherapy intensity-modulated radiation therapy (IMRT) followed by interstitial high-dose-rate (HDR) brachytherapy. A 54-year-old female with an inoperable pelvic-supravaginal 5.6 cm T3N0M0 PP-CCC tumor underwent treatment with 6 cycles of carboplatin and taxol chemotherapy. Postchemotherapy PET/CT scan revealed a residual 3.3 cm tumor. The patient underwent CT and MR planning simulation, and was treated with 50 Gy to the primary tumor and 45 Gy to the pelvis including the pelvic lymph nodes, using IMRT to spare bowel. Subsequently, the patient was treated with an interstitial HDR brachytherapy implant, planned using both CT and MR scans. A total dose of 15 Gy in 5 Gy fractions over two days was delivered with Ir-192 HDR brachytherapy. The total prescribed equivalent 2 Gy dose (EQD2) to the HDR planning target volume (PTV) from both the EBRT and HDR treatments ranged between 63 and 68.8 Gy2 due to differential dosing of the primary and pelvic targets. The patient tolerated radiotherapy well, except for mild diarrhea not requiring medication. There was no patient-reported acute toxicity one month following the radiotherapy course. At four months following adjuvant radiation therapy, the patient had near complete resolution of local tumor on PET/CT without any radiation-associated toxicity. However, the patient was noted to have metastatic disease outside of the radiation field, specifically lesions in the liver and bone. This case report illustrates the feasibility of the treatment of a pelvic PP-CCC with IMRT followed by interstitial HDR brachytherapy boost, which resulted in near complete local tumor response without significant morbidity.


Subject(s)
Adenocarcinoma, Clear Cell/radiotherapy , Brachytherapy , Dose Fractionation, Radiation , Peritoneal Neoplasms/radiotherapy , Radiotherapy Planning, Computer-Assisted , Radiotherapy, Intensity-Modulated , Feasibility Studies , Female , Follow-Up Studies , Humans , Lymph Nodes/radiation effects , Middle Aged , Organs at Risk , Pelvis/radiation effects , Positron-Emission Tomography , Prognosis , Radiotherapy, Conformal , Tomography, X-Ray Computed
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