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1.
Front Public Health ; 12: 1408222, 2024.
Article in English | MEDLINE | ID: mdl-39005996

ABSTRACT

Understanding the health outcomes of military exposures is of critical importance for Veterans, their health care team, and national leaders. Approximately 43% of Veterans report military exposure concerns to their VA providers. Understanding the causal influences of environmental exposures on health is a complex exposure science task and often requires interpreting multiple data sources; particularly when exposure pathways and multi-exposure interactions are ill-defined, as is the case for complex and emerging military service exposures. Thus, there is a need to standardize clinically meaningful exposure metrics from different data sources to guide clinicians and researchers with a consistent model for investigating and communicating exposure risk profiles. The Linked Exposures Across Databases (LEAD) framework provides a unifying model for characterizing exposures from different exposure databases with a focus on providing clinically relevant exposure metrics. Application of LEAD is demonstrated through comparison of different military exposure data sources: Veteran Military Occupational and Environmental Exposure Assessment Tool (VMOAT), Individual Longitudinal Exposure Record (ILER) database, and a military incident report database, the Explosive Ordnance Disposal Information Management System (EODIMS). This cohesive method for evaluating military exposures leverages established information with new sources of data and has the potential to influence how military exposure data is integrated into exposure health care and investigational models.


Subject(s)
Databases, Factual , Environmental Exposure , Military Personnel , Humans , Military Personnel/statistics & numerical data , Veterans/statistics & numerical data , Common Data Elements , Occupational Exposure , United States
2.
Ecol Evol ; 14(7): e11649, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38952663

ABSTRACT

Drylands are unique among terrestrial ecosystems in that they have a significant proportion of primary production facilitated by non-vascular plants such as colonial cyanobacteria, moss, and lichens, i.e., biocrusts, which occur on and in the surface soil. Biocrusts inhabit all continents, including Antarctica, an increasingly dynamic continent on the precipice of change. Here, we describe in-situ field surveying and sampling, remote sensing, and modeling approaches to assess the habitat suitability of biocrusts in the Lake Fryxell basin of Taylor Valley, Antarctica, which is the main site of the McMurdo Dry Valleys Long-Term Ecological Research Program. Soils suitable for the development of biocrusts are typically wetter, less alkaline, and less saline compared to unvegetated soils. Using random forest models, we show that gravimetric water content, electrical conductivity, and snow frequency are the top predictors of biocrust presence and biomass. Areas most suitable for the growth of dense biocrusts are soils associated with seasonal snow patches. Using geospatial data to extrapolate our habitat suitability model to the whole basin predicts that biocrusts are present in 2.7 × 105 m2 and contain 11-72 Mg of aboveground carbon, based on the 90% probability of occurrence. Our study illustrates the synergistic effect of combining field and remote sensing data for understanding the distribution and biomass of biocrusts, a foundational community in the carbon balance of this region. Extreme weather events and changing climate conditions in this region, especially those influencing snow accumulation and persistence, could have significant effects on the future distribution and abundance of biocrusts and therefore soil organic carbon storage in the McMurdo Dry Valleys.

3.
Med Phys ; 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38923579

ABSTRACT

BACKGROUND: Magnetic hyperthermia (MHT) has emerged as a promising therapeutic approach in the field of radiation oncology due to its superior precision in controlling temperature and managing the heating area compared to conventional hyperthermia. Recent studies have proposed solutions to address clinical safety concerns associated with MHT, which arise from the use of highly concentrated magnetic nanoparticles and the strong magnetic field needed to induce hyperthermic effects. Despite these efforts, challenges remain in quantifying therapeutic outcomes and developing treatment plan systems for combining MHT with radiation therapy (RT). PURPOSE: This study aims to quantitatively measure the therapeutic effect, including radiation dose enhancement (RDE) in the magnetic hyperthermia-radiation combined therapy (MHRT), using the equivalent radiation dose (EQD) estimation method. METHODS: To conduct EQD estimation for MHRT, we compared the therapeutic effects between the conventional hyperthermia-radiation combined therapy (HTRT) and MHRT in human prostate cancer cell lines, PC3 and LNCaP. We adopted a clonogenic assay to validate RDE and the radiosensitizing effect induced by MHT. The data on survival fractions were analyzed using both the linear-quadradic model and Arrhenius model to estimate the biological parameters describing RDE and radiosensitizing effect of MHRT for both cell lines through maximum likelihood estimation. Based on these parameters, a new survival fraction model was suggested for EQD estimation of MHRT. RESULTS: The newly designed model describing the MHRT effect, effectively captures the variations in thermal and radiation dose for both cell lines (R2 > 0.95), and its suitability was confirmed through the normality test of residuals. This model appropriately describes the survival fractions up to 10 Gy for PC3 cells and 8 Gy for LNCaP cells under RT-only conditions. Furthermore, using the newly defined parameter r, the RDE effect was calculated as 29% in PC3 cells and 23% in LNCaP cells. EQDMHRT calculated through this model was 9.47 Gy for PC3 and 4.71 Gy for LNCaP when given 2 Gy and MHT for 30 min. Compared to EQDHTRT, EQDMHRT showed a 26% increase for PC3 and a 20% increase for LNCaP. CONCLUSIONS: The proposed model effectively describes the changes of the survival fraction induced by MHRT in both cell lines and adequately represents actual data values through residual analysis. Newly suggested parameter r for RDE effect shows potential for quantitative comparisons between HTRT and MHRT, and optimizing therapeutic outcomes in MHRT for prostate cancer.

4.
Mil Med ; 189(7-8): e1414-e1416, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38836853

ABSTRACT

INTRODUCTION: In the Medscape 2020 Compensation Report, family physicians ranked low for feeling fairly compensated, choosing their specialty again and choosing medicine again. However, the Medscape data may not represent military family physicians. METHODS: A large survey was emailed to 2,562 military family physicians via a military professional organization list-serve from February to April 2021. The inquiry included 6 statements pertaining to professional satisfaction. The main outcome measures were proportions of "agree" and "strongly agree." The proportions were compared to the Medscape Compensation Report 2020 and 2022. Statistical analysis was completed with a two-tailed Z-score for 2 populations. RESULTS: Sixty-one percent of military family physicians feel fairly compensated compared to 54% of civilian family physicians in 2020 and 55% in 2022 (P = .065, .119). Eighty-six percent of military family physicians would reselect medicine compared to 74% of civilian family physicians in 2020 and 73% in 2022 (P < .001 for both). Eighty percent of military family physicians would reselect their specialty again compared to 70% of civilians in 2020 and 68% in 2022 (P = .004, P = .001, respectively). CONCLUSIONS: Military family physicians were more likely to choose medicine generally and family medicine specifically again. Military family physicians and civilian family physicians do not statistically differ in feeling fairly compensated. A strong majority of military family physicians are satisfied with their military-sponsored medical education.


Subject(s)
Job Satisfaction , Military Personnel , Physicians, Family , Humans , Physicians, Family/statistics & numerical data , Physicians, Family/psychology , Physicians, Family/trends , Surveys and Questionnaires , Male , Female , Military Personnel/statistics & numerical data , Military Personnel/psychology , Adult , Middle Aged , Personal Satisfaction , United States , Military Medicine/statistics & numerical data , Military Medicine/methods , Military Medicine/standards , Military Medicine/trends
5.
Head Neck ; 2024 May 23.
Article in English | MEDLINE | ID: mdl-38779999

ABSTRACT

BACKGROUND: Transoral surgical resectability (TOS) is a prognostic factor for patients with HPV+ T1-2 oropharyngeal squamous cell carcinoma (OPSCC) disease undergoing radiotherapy (RT), but it is unclear whether this holds for HPV-negative (HPV-) patients. We aimed to compare outcomes of potential TOS-candidates vs. non-TOS candidates, among patients who underwent RT/CRT for early T-stage HPV- OPSCC. METHODS: For patients treated with RT/CRT for early T-stage HPV-negative OPSCC between 2014 and 2021, pretreatment imaging was reviewed by four head-and-neck surgeons, masked to clinical outcomes, to assess primary-site suitability for TOS. Extracapsular extension (ECE) was assessed by a head-and-neck neuroradiologist. We compared outcomes based on surgical resectability relating to: (1) the primary site tumor alone, and (2) the primary site plus the absence/presence of ECE (overall assessment). Kaplan-Meier curves for overall survival (OS), disease-specific survival (DSS), and progression-free survival (PFS) were compared using the log-rank test. RESULTS: Seventy patients were included in the analysis. The primary site was TOS-favorable in 46/70 (66%). Based on the overall assessment, 41/70 (58.6%) were TOS-favorable. The 3-year OS, DSS and PFS for primary site TOS-favorable versus unfavorable were OS: 76.9% versus 37.4%; DSS: 78.1% versus 46.2%, PFS: 69.9% versus 41.3%, (log-rank test = 0.01, 0.03, 0.04; respectively). Additionally, patients with an overall assessment of TOS favorability demonstrated better survival outcomes compared with TOS-unfavorable patients (OS: 77.3% vs. 46.2%; DSS: 78.2% vs. 56.5%, PFS: 72.3% vs. 42.1%, log-rank test = 0.01, 0.04, 0.01; respectively). CONCLUSION: Patients with TOS-favorable HPV-negative early T-stage OPSCC have superior survival outcomes than TOS-unfavorable patients.

6.
Front Endocrinol (Lausanne) ; 15: 1298423, 2024.
Article in English | MEDLINE | ID: mdl-38567308

ABSTRACT

Estrogen receptor positive (ER+) breast cancer is the most common breast cancer diagnosed annually in the US with endocrine-based therapy as standard-of-care for this breast cancer subtype. Endocrine therapy includes treatment with antiestrogens, such as selective estrogen receptor modulators (SERMs), selective estrogen receptor downregulators (SERDs), and aromatase inhibitors (AIs). Despite the appreciable remission achievable with these treatments, a substantial cohort of women will experience primary tumor recurrence, subsequent metastasis, and eventual death due to their disease. In these cases, the breast cancer cells have become resistant to endocrine therapy, with endocrine resistance identified as the major obstacle to the medical oncologist and patient. To combat the development of endocrine resistance, the treatment options for ER+, HER2 negative breast cancer now include CDK4/6 inhibitors used as adjuvants to antiestrogen treatment. In addition to the dysregulated activity of CDK4/6, a plethora of genetic and biochemical mechanisms have been identified that contribute to endocrine resistance. These mechanisms, which have been identified by lab-based studies utilizing appropriate cell and animal models of breast cancer, and by clinical studies in which gene expression profiles identify candidate endocrine resistance genes, are the subject of this review. In addition, we will discuss molecular targeting strategies now utilized in conjunction with endocrine therapy to combat the development of resistance or target resistant breast cancer cells. Of approaches currently being explored to improve endocrine treatment efficacy and patient outcome, two adaptive cell survival mechanisms, autophagy, and "reversible" senescence, are considered molecular targets. Autophagy and/or senescence induction have been identified in response to most antiestrogen treatments currently being used for the treatment of ER+ breast cancer and are often induced in response to CDK4/6 inhibitors. Unfortunately, effective strategies to target these cell survival pathways have not yet been successfully developed. Thus, there is an urgent need for the continued interrogation of autophagy and "reversible" senescence in clinically relevant breast cancer models with the long-term goal of identifying new molecular targets for improved treatment of ER+ breast cancer.


Subject(s)
Breast Neoplasms , Animals , Female , Humans , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Estrogen Receptor Modulators/pharmacology , Estrogen Receptor Modulators/therapeutic use , Drug Resistance, Neoplasm/genetics , Neoplasm Recurrence, Local/drug therapy , Receptors, Estrogen/metabolism , Autophagy
7.
Cureus ; 16(2): e53645, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38449937

ABSTRACT

Recurrent or metastatic head and neck squamous cell carcinoma (RMHNSCC) is associated with a poor prognosis and short survival duration. There is an urgent need to identify personalized predictors of drug response to guide the selection of the most effective therapy for each individual recurrence. We tested the feasibility of patient-derived xenografts (PDX) for guiding their RMHNSCC salvage treatment. Fresh tumor samples from eligible, consented patients were implanted into mice. Established tumors were expanded in mouse PDX cohorts to identify responses to candidate salvage drug treatments in parallel testing. Patients alive and suitable for chemotherapy were treated based on responses determined by PDX testing. Nine patient tumors were successfully engrafted in mice with an average time of 89.2±41.7 days. Four patients' PDX models underwent parallel drug testing. Two patients received PDX-guided therapy. In one of these patients, single agents of cetuximab and paclitaxel demonstrated the best responses in the PDX model, and this patient exhibited sequential partial responses to each drug, including a 17-month clinical response to cetuximab. The main limitation of PDX testing for RMHNSCC was the time delay in obtaining testing results. Despite this, parallel PDX testing may be feasible for a subset of patients and appears to correlate with clinical benefit.

8.
J Addict Med ; 18(2): 209-211, 2024.
Article in English | MEDLINE | ID: mdl-38227854

ABSTRACT

INTRODUCTION: Buprenorphine extended-release subcutaneous injection (BUP-XR) is a medication used to treat opioid use disorder. It is a long-acting formulation of buprenorphine, which is a partial opioid agonist. Buprenorphine extended-release subcutaneous injection is injected into the subcutaneous space forming a depot that can last up to a month. The most common adverse effects of BUP-XR are injection site pain, erythema, and induration. CASE REPORT: A man in his late 30s presented to the emergency department 48 hours after BUP-XR injection with abdominal pain. He was found to have superficial venous thrombosis of an abdominal wall vessel extending near the deep venous system. He was subsequently started on apixaban for 30 days and cefadroxil for 7 days to reduce the risk of extension and infection. He fully recovered and has since restarted BUP-XR without further complications. CONCLUSIONS: Venous thrombosis is a rare but potentially life-threatening complication of BUP-XR. It is important for emergency and outpatient clinicians to be aware of adverse reactions associated with this medication. The patient was successfully treated with a 30-day course of apixaban and able to resume taking BUP-XR without further complications. Clinicians may want to consider supplementing BUP-XR with sublingual film after injection-related complications due to possible lower serum levels.


Subject(s)
Buprenorphine , Opioid-Related Disorders , Thrombophlebitis , Male , Humans , Narcotic Antagonists/therapeutic use , Naltrexone/therapeutic use , Buprenorphine/therapeutic use , Opioid-Related Disorders/drug therapy , Delayed-Action Preparations/therapeutic use , Thrombophlebitis/chemically induced , Thrombophlebitis/drug therapy , Analgesics, Opioid/therapeutic use
10.
Head Neck ; 46(2): 353-366, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38059331

ABSTRACT

BACKGROUND: Adverse pathological features following surgery in head and neck squamous cell carcinoma (HNSCC) are strongly associated with survival and guide adjuvant therapy. We investigated molecular changes associated with these features. METHODS: We downloaded data from the Cancer Genome Atlas and Cancer Proteome Atlas HNSCC cohorts. We compared tumors positive versus negative for perineural invasion (PNI), lymphovascular invasion (LVI), extracapsular spread (ECS), and positive margins (PSM), with multivariable analysis. RESULTS: All pathological features were associated with poor survival, as were the following molecular changes: low cyclin E1 (HR = 1.7) and high PKC-alpha (HR = 1.8) in tumors with PNI; six of 13 protein abundance changes with LVI; greater tumor hypoxia and high Raptor (HR = 2.0) and Rictor (HR = 1.6) with ECS; and low p38 (HR = 2.3), high fibronectin (HR = 1.6), low annexin A1 (HR = 3.1), and high caspase-9 (HR = 1.6) abundances with PSM. CONCLUSIONS: Pathological features in HNSCC carry specific molecular changes that may explain their poor prognostic associations.


Subject(s)
Head and Neck Neoplasms , Papillomavirus Infections , Humans , Squamous Cell Carcinoma of Head and Neck/genetics , Head and Neck Neoplasms/genetics , Prognosis , Combined Modality Therapy
11.
Head Neck ; 46(3): 503-512, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38100227

ABSTRACT

BACKGROUND: We aimed to analyze and compare the timing and patterns of treatment failure, and survival after progression between HPV-positive (HPV+) and HPV-negative (HPV-) patients undergoing chemoradiation for oropharyngeal squamous cell carcinomas (OPSCC). METHODS: A retrospective review was performed of all patients undergoing primary chemoradiation for OPSCC between 2008 and 2021. Demographic and clinical data were collected. Kaplan-Meier estimates for overall survival (OS), and time to recurrence/metastases (TTR) were compared using the log-rank test, with Cox regression used for multivariable modeling comparing HPV+ and HPV- patients. RESULTS: HPV- patients developed recurrence or metastases at earlier time points than HPV+ patients (8.8 vs. 15.2 months, p < 0.05), due to earlier local/locoregional recurrence and distant metastases, but not isolated regional recurrences. HPV- distant metastases exclusively occurred in a single organ, most commonly the lungs or bone, while HPV+ metastases frequently had multi-organ involvement in a wide variety of locations (p < 0.05). Once progression (recurrence/metastases) was diagnosed, HPV+ patients experienced superior survival to HPV- patients on univariate and multivariate analysis, largely due to improved outcomes after treatment of local/locoregional recurrences (p < 0.05). There were no differences in survival after isolated regional recurrences or distant metastases. CONCLUSION: HPV+ OPSCC patients relapse later compared to HPV- patients in local/locoregional and distant sites. HPV+ patients with local/locoregional recurrence experience superior survival after recurrence, which does not hold true for isolated regional recurrences or distant metastases. These data can be useful to inform prognosis and guide treatment decisions in patients with recurrent OPSCC.


Subject(s)
Carcinoma, Squamous Cell , Head and Neck Neoplasms , Oropharyngeal Neoplasms , Papillomavirus Infections , Humans , Squamous Cell Carcinoma of Head and Neck/therapy , Carcinoma, Squamous Cell/pathology , Oropharyngeal Neoplasms/pathology , Papillomavirus Infections/complications , Papillomavirus Infections/therapy , Neoplasm Recurrence, Local/pathology , Prognosis , Treatment Failure , Retrospective Studies
12.
Cureus ; 15(11): e48316, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38058352

ABSTRACT

Laryngeal cancer most frequently develops in males aged 60-70 years with a history of tobacco and/or alcohol use, while fewer cases occur in young patients in which tobacco and alcohol are often absent or less significant, highlighting the importance of other etiologies. We present cases of human papillomavirus (HPV)-associated laryngeal cancer in two previously healthy young women. A retrospective case review was carried out for both patients. DNA was extracted from the primary tumors and matched to normal tissue or blood, HPV genotype was determined by PCR and whole exome sequencing was carried out. Genomic results were pooled with laryngeal cancer patients from the cancer genome atlas (TCGA) dataset. The first patient was an 18-year-old female who underwent laryngectomy followed by adjuvant radiation. The second was a 24-year-old female who received chemoradiation. The first patient has remained disease-free for 16 years and the second for two years; both continue to be monitored. One tumor was positive for HPV45 and had mutations in FAT1 and FAT2; the other was positive for HPV31 and had mutations at NOTCH1, MAPK1, and HIST1H2AK. Both tumors had wild-type TP53 alleles. We bring attention to HPV as an etiology of laryngeal carcinoma in young patients, which may have implications for the treatment and prognosis of similar patients.

13.
Viruses ; 15(12)2023 12 12.
Article in English | MEDLINE | ID: mdl-38140652

ABSTRACT

Human papillomavirus (HPV) is the major causative agent for cervical and many head and neck cancers (HNCs). HPVs randomly acquire single nucleotide polymorphisms (SNPs) that may become established via positive selection. Within an HPV type, viral isolates differing by <2% in the L1 region are termed "variants" and classified based on combinations of SNPs. Studies in cervical cancer demonstrate clear differences between HPV16 intratypic variants in terms of persistence of infection, tumor histology, cancer risk, and death. Much less is known about the frequency of HPV16 variants in HNC, and their effects on clinical outcomes. We combined HPV16 positive (HPV16+) HNC samples from a local Southwestern Ontario, Canada cohort with those from the Cancer Genome Atlas to create a larger North American cohort of 149 cases with clinical data and determined the distribution of intratypic variants and their impact on clinical outcomes. Most isolates were lineage A, sublineage A1, or A2, with roughly half exhibiting the T350G polymorphism in E6. Univariable analysis identified significant differences between 350T and 350G intratypic variants in clinical T, N, and O staging, as well as disease-free survival. Multivariable analysis failed to identify any clinical factor as a statistically significant covariate for disease-free survival differences between 350T and 350G. Significant differences in several measures of B-cell mediated immune response were also observed between 350T and 350G intratypic variants. We suggest that HPV genetic variation may be associated with HNC clinical characteristics and may have prognostic value.


Subject(s)
Head and Neck Neoplasms , Oncogene Proteins, Viral , Papillomavirus Infections , Uterine Cervical Neoplasms , Female , Humans , Human papillomavirus 16/genetics , Polymorphism, Single Nucleotide , Head and Neck Neoplasms/genetics , North America , Ontario , Oncogene Proteins, Viral/genetics
14.
Front Psychiatry ; 14: 1180929, 2023.
Article in English | MEDLINE | ID: mdl-37965360

ABSTRACT

Introduction: In 2016 diplomatic personnel serving in Havana, Cuba, began reporting audible sensory phenomena paired with onset of complex and persistent neurological symptoms consistent with brain injury. The etiology of these Anomalous Health Incidents (AHI) and subsequent symptoms remains unknown. This report investigates putative exposure-symptom pathology by assembling a network model of published bio-behavioral pathways and assessing how dysregulation of such pathways might explain loss of function in these subjects using data available in the published literature. Given similarities in presentation with mild traumatic brain injury (mTBI), we used the latter as a clinically relevant means of evaluating if the neuropsychological profiles observed in Havana Syndrome Havana Syndrome might be explained at least in part by a dysregulation of neurotransmission, neuro-inflammation, or both. Method: Automated text-mining of >9,000 publications produced a network consisting of 273 documented regulatory interactions linking 29 neuro-chemical markers with 9 neuropsychological constructs from the Brief Mood Survey, PTSD Checklist, and the Frontal Systems Behavior Scale. Analysis of information flow through this network produced a set of regulatory rules reconciling to within a 6% departure known mechanistic pathways with neuropsychological profiles in N = 6 subjects. Results: Predicted expression of neuro-chemical markers that jointly satisfy documented pathways and observed symptom profiles display characteristically elevated IL-1B, IL-10, NGF, and norepinephrine levels in the context of depressed BDNF, GDNF, IGF1, and glutamate expression (FDR < 5%). Elevations in CRH and IL-6 were also predicted unanimously across all subjects. Furthermore, simulations of neurological regulatory dynamics reveal subjects do not appear to be "locked in" persistent illness but rather appear to be engaged in a slow recovery trajectory. Discussion: This computational analysis of measured neuropsychological symptoms in Havana-based diplomats proposes that these AHI symptoms may be supported in part by disruption of known neuroimmune and neurotransmission regulatory mechanisms also associated with mTBI.

15.
Oral Oncol ; 146: 106580, 2023 11.
Article in English | MEDLINE | ID: mdl-37778229

ABSTRACT

OBJECTIVES: Although human papillomavirus positive (HPV+) oropharyngeal squamous cell carcinoma (OPSCC) patients typically experience excellent survival, 15-20 % of patients recur after treatment with chemotherapy and radiation. Therefore, there is a need for biomarkers of treatment failure to guide treatment intensity. MATERIALS AND METHODS: Whole genome sequencing was carried out on HPV+OPSCC patients who were primarily treated with concurrent chemotherapy (cisplatin) and radiation. We then explored whether the loss of LRP1Bwas sufficient to drive an aggressive phenotype, and promote a resistance to cisplatin and radiation therapy both in vitro using HPV+ cell lines (93VU147T, UMSCC47, UWO37 and UWO23) and in vivo. RESULTS: Through integrative genomic analysis of three HPV+OPSCC tumour datasets, we identified that deletion of LRP1B was enriched in samples that recurred following chemo-radiation. Knockdown using siRNA in four HPV+ cell lines (UWO23, UWO37, UMSCC47 and 93VU147T) resulted in increased proliferation of all cases. CRISPR/Cas9 deletion of LRP1B in the same cell line panel demonstrated increased proliferation, clonogenic growth and migration, as well as resistance to both cisplatin and radiation in LRP1B deleted cells compared to their respective non-targeting control cells. Cell line derived xenograft studies indicated that the LRP1B knockout tumours were more resistant to cisplatin and radiation therapy compared to their controls invivo. CONCLUSION: Taken together, our work implicates LRP1B deletion as a potential biomarker for identifying treatment resistant HPV+ OPSCC cases.


Subject(s)
Carcinoma, Squamous Cell , Drug Resistance, Neoplasm , Head and Neck Neoplasms , Oropharyngeal Neoplasms , Papillomavirus Infections , Radiation Tolerance , Humans , Carcinoma, Squamous Cell/pathology , Cisplatin/pharmacology , Cisplatin/therapeutic use , Head and Neck Neoplasms/drug therapy , Head and Neck Neoplasms/genetics , Head and Neck Neoplasms/radiotherapy , Neoplasm Recurrence, Local , Papillomavirus Infections/complications , Papillomavirus Infections/genetics , Papillomavirus Infections/pathology , Receptors, LDL/therapeutic use , Squamous Cell Carcinoma of Head and Neck/genetics , Squamous Cell Carcinoma of Head and Neck/radiotherapy
16.
Eur Radiol Exp ; 7(1): 42, 2023 08 15.
Article in English | MEDLINE | ID: mdl-37580614

ABSTRACT

BACKGROUND: Despite widespread study of dendritic cell (DC)-based cancer immunotherapies, the in vivo postinjection fate of DC remains largely unknown. Due in part to a lack of quantifiable imaging modalities, this is troubling as the amount of DC migration to secondary lymphoid organs correlates with therapeutic efficacy. Magnetic particle imaging (MPI) has emerged as a suitable modality to quantify in vivo migration of superparamagnetic iron oxide (SPIO)-labeled DC. Herein, we describe a popliteal lymph node (pLN)-focused MPI scan to quantify DC in vivo migration accurately and consistently. METHODS: Adenovirus (Ad)-transduced SPIO+ (Ad SPIO+) and SPIO+ C57BL/6 bone marrow-derived DC were generated and assessed for viability and phenotype, then fluorescently labeled and injected into mouse hind footpads (n = 6). Two days later, in vivo DC migration was quantified using whole animal, pLN-focused, and ex vivo pLN MPI scans. RESULTS: No significant differences in viability, phenotype and in vivo pLN migration were noted for Ad SPIO+ and SPIO+ DC. Day 2 pLN-focused MPI quantified DC migration in all instances while whole animal MPI only quantified pLN migration in 75% of cases. Ex vivo MPI and fluorescence microscopy confirmed that pLN MPI signal was due to originally injected Ad SPIO+ and SPIO+ DC. CONCLUSION: We overcame a reported limitation of MPI by using a pLN-focused MPI scan to quantify pLN-migrated Ad SPIO+ and SPIO+ DC in 100% of cases and detected as few as 1000 DC (4.4 ng Fe) in vivo. MPI is a suitable preclinical imaging modality to assess DC-based cancer immunotherapeutic efficacy. RELEVANCE STATEMENT: Tracking the in vivo fate of DC using noninvasive quantifiable magnetic particle imaging can potentially serve as a surrogate marker of therapeutic effectiveness. KEY POINTS: • Adenoviral-transduced and iron oxide-labeled dendritic cells are in vivo migration competent. • Magnetic particle imaging is a suitable modality to quantify in vivo dendritic cell migration. • Magnetic particle imaging focused field of view overcomes dynamic range limitation.


Subject(s)
Bone Marrow , Magnetic Resonance Imaging , Animals , Mice , Cell Movement , Magnetic Resonance Imaging/methods , Mice, Inbred C57BL , Adenoviridae , Dendritic Cells , Magnetic Phenomena
17.
J Appl Clin Med Phys ; 24(8): e14009, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37158727

ABSTRACT

Stereotactic radiotherapy (SRT) methods have become common for the treatment of small tumors in various parts of the body. Small field dosimetry has a unique set of challenges when it comes to the pre-treatment validation of a radiotherapy plan that involves film dosimetry or high-resolution detectors. Comparison of commercial quality assurance (QA) devices to the film dosimetry method for pre-treatment evaluation of stereotactic radiosurgery (SRS), fractionated SRT, and stereotactic body radiation therapy treatment plans have been evaluated in this study. Forty stereotactic QA plans were measured using EBT-XD film, IBA Matrixx Resolution, SNC ArcCHECK, Varian aS1200 EPID, SNC SRS MapCHECK, and IBA myQA SRS. The results of the commercial devices are compared to the EBT-XD film dosimetry results for each gamma criteria. Treatment plan characteristics such as modulation factor and target volume were investigated for correlation with the passing rates. It was found that all detectors have greater than 95% passing rates at 3%/3 mm. Passing rates decrease rapidly for ArcCHECK and the Matrixx as criteria became more strict. In contrast, EBT-XD film, SNC SRS MapCHECK, and IBA myQA SRS passing rates do not decline as rapidly when compared to Matrix Resolution, ArcCHECK, and the EPID. EBT-XD film, SNC SRS MapCHECK, and IBA myQA SRS maintain greater than 90% passing rate at 2%/1 mm and greater than 80% at 1%/1 mm. Additionally, the ability of these devices to detect changes in dose distribution due to MLC positioning errors was investigated. Ten VMAT SBRT/SRS treatment plans were created with 6 MV FFF or 10 MV FFF beam energies using Eclipse 15.6. A MATLAB script was used to create two MLC positioning error scenarios from the original treatment plan. It was found that errors in MLC positioning were most reliably detected at 2%/1 mm for high-resolution detectors and that lower-resolution detectors did not consistently detect MLC positioning errors.


Subject(s)
Radiosurgery , Radiotherapy, Intensity-Modulated , Humans , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted/methods , Quality Assurance, Health Care , Radiometry/methods , Radiotherapy, Intensity-Modulated/methods
18.
J Neurophysiol ; 129(3): 700-716, 2023 03 01.
Article in English | MEDLINE | ID: mdl-36752512

ABSTRACT

Many studies of Ca2+ effects on mitochondrial respiration in intact cells have used electrical and/or chemical stimulation to elevate intracellular [Ca2+], and have reported increases in [NADH] and increased ADP/ATP ratios as dominant controllers of respiration. This study tested a different form of stimulation: brief temperature increases produced by pulses of infrared light (IR, 1,863 nm, 8-10°C for ∼5 s). Fluorescence imaging techniques applied to single PC-12 cells in low µM extracellular [Ca2+] revealed IR stimulation-induced increases in both cytosolic (fluo5F) and mitochondrial (rhod2) [Ca2+]. IR stimulation increased O2 consumption (porphyrin fluorescence), and produced an alkaline shift in mitochondrial matrix pH (Snarf1), indicating activation of the electron transport chain (ETC). The increase in O2 consumption persisted in oligomycin, and began during a decrease in NADH, suggesting that the initial increase in ETC activity was not driven by increased ATP synthase activity or an increased fuel supply to ETC complex I. Imaging with two potentiometric dyes [tetramethyl rhodamine methyl ester (TMRM) and R123] indicated a depolarizing shift in ΔΨm that persisted in high [K+] medium. High-resolution fluorescence imaging disclosed large, reversible mitochondrial depolarizations that were inhibited by cyclosporin A (CSA), consistent with the opening of transient mitochondrial permeability transition pores. IR stimulation also produced a Ca2+-dependent increase in superoxide production (MitoSox) that was not inhibited by CSA, indicating that the increase in superoxide did not require transition pore opening. Thus, the intracellular Ca2+ release that follows pulses of infrared light offers new insights into Ca2+-dependent processes controlling respiration and reactive oxygen species in intact cells.NEW & NOTEWORTHY Pulses of infrared light (IR) provide a novel method for rapidly transferring Ca2+ from the endoplasmic reticulum to mitochondria in intact cells. In PC12 cells the resulting ETC activation was not driven by increased ATP synthase activity or NADH. IR stimulation produced a Ca2+-dependent, reversible depolarization of ΔΨm that was partially blocked by cyclosporin A, and a Ca2+-dependent increase in superoxide that did not require transition pore opening.


Subject(s)
Cyclosporine , Mitochondrial Membrane Transport Proteins , Rats , Animals , Mitochondrial Membrane Transport Proteins/pharmacology , Mitochondrial Membrane Transport Proteins/physiology , Cyclosporine/pharmacology , Superoxides/pharmacology , NAD/pharmacology , Mitochondria , Adenosine Triphosphate/pharmacology , Calcium
20.
Mil Med ; 188(3-4): 689-696, 2023 03 20.
Article in English | MEDLINE | ID: mdl-35446430

ABSTRACT

INTRODUCTION: To evaluate the associations between neurocognitive and psychiatric health outcomes with mefloquine or any antimalarial exposure. MATERIALS AND METHODS: Medical records were systematically reviewed to identify veterans that indicated antimalarial medication use. Linear regression was performed to examine associations between mefloquine/antimalarial exposure and health outcomes. The mefloquine-exposed group was further compared with normative populations for the same health outcomes. RESULTS: In the adjusted models, no significant differences were noted between the two exposure groups and the unexposed group for any of the health measures (P-value > 0.05). When compared to normative population samples, the mefloquine-exposed group had poorer health and greater neurobehavioral symptom severity or cognitive complaints. CONCLUSION: This study suggests that mefloquine use by veterans referred for intensive evaluation of their military deployment exposures and health was not associated with increased, long-term, neurocognitive/psychiatric symptoms compared to unexposed veterans.


Subject(s)
Antimalarials , Veterans , Humans , Mefloquine/adverse effects , Antimalarials/adverse effects , Veterans/psychology , Cross-Sectional Studies , Cohort Studies
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