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1.
Front Oncol ; 14: 1387251, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38715789

RESUMO

Cancer treatment is associated with long lasting cognitive impairment in cancer survivors. This cognitive impairment is often termed cancer related cognitive impairment (CRCI). Cancer survivors treated for tumors outside the central nervous system are increasingly diagnosed with CRCI. The development of strategies to mitigate the negative effects of cancer treatment on the brain are crucial. Although neuroimaging research has proposed several candidate mechanisms, the pathogenic underpinnings of CRCI remain uncertain. As such, preventative and treatment strategies have not been identified. To fill these gaps, animal models play a vital role in isolating underlying contributing mechanisms that promote CRCI and in testing new therapeutic approaches.

2.
Int J Radiat Oncol Biol Phys ; 119(1): 42-55, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38042450

RESUMO

Radiation therapy (RT) has been a primary treatment modality in cancer for decades. Increasing evidence suggests that RT can induce an immunosuppressive shift via upregulation of cells such as tumor-associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs). MDSCs inhibit antitumor immunity through potent immunosuppressive mechanisms and have the potential to be crucial tools for cancer prognosis and treatment. MDSCs interact with many different pathways, desensitizing tumor tissue and interacting with tumor cells to promote therapeutic resistance. Vascular damage induced by RT triggers an inflammatory signaling cascade and potentiates hypoxia in the tumor microenvironment (TME). RT can also drastically modify cytokine and chemokine signaling in the TME to promote the accumulation of MDSCs. RT activation of the cGAS-STING cytosolic DNA sensing pathway recruits MDSCs through a CCR2-mediated mechanism, inhibiting the production of type 1 interferons and hampering antitumor activity and immune surveillance in the TME. The upregulation of hypoxia-inducible factor-1 and vascular endothelial growth factor mobilizes MDSCs to the TME. After recruitment, MDSCs promote immunosuppression by releasing reactive oxygen species and upregulating nitric oxide production through inducible nitric oxide synthase expression to inhibit cytotoxic activity. Overexpression of arginase-1 on subsets of MDSCs degrades L-arginine and downregulates CD3ζ, inhibiting T-cell receptor reactivity. This review explains how radiation promotes tumor resistance through activation of immunosuppressive MDSCs in the TME and discusses current research targeting MDSCs, which could serve as a promising clinical treatment strategy in the future.


Assuntos
Células Supressoras Mieloides , Neoplasias , Humanos , Células Supressoras Mieloides/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Neoplasias/patologia , Microambiente Tumoral , Imunossupressores , Hipóxia/metabolismo
3.
Front Immunol ; 14: 1284118, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38022656

RESUMO

Introduction: Treatment for glioblastomas, aggressive and nearly uniformly fatal brain tumors, provide limited long-term success. Immunosuppression by myeloid cells in both the tumor microenvironment and systemic circulation are believed to contribute to this treatment resistance. Standard multi-modality therapy includes conventionally fractionated radiotherapy over 6 weeks; however, hypofractionated radiotherapy over 3 weeks or less may be appropriate for older patients or populations with poor performance status. Lymphocyte concentration changes have been reported in patients with glioblastoma; however, monocytes are likely a key cell type contributing to immunosuppression in glioblastoma. Peripheral monocyte concentration changes in patients receiving commonly employed radiation fractionation schemes are unknown. Methods: To determine the effect of conventionally fractionated and hypofractionated radiotherapy on complete blood cell leukocyte parameters, retrospective longitudinal concentrations were compared prior to, during, and following standard chemoradiation treatment. Results: This study is the first to report increased monocyte concentrations and decreased lymphocyte concentrations in patients treated with conventionally fractionated radiotherapy compared to hypofractionated radiotherapy. Discussion: Understanding the impact of fractionation on peripheral blood leukocytes is important to inform selection of dose fractionation schemes for patients receiving radiotherapy.


Assuntos
Glioblastoma , Humanos , Glioblastoma/radioterapia , Glioblastoma/patologia , Resultado do Tratamento , Estudos Retrospectivos , Hipofracionamento da Dose de Radiação , Leucócitos/patologia , Microambiente Tumoral
4.
Vet Radiol Ultrasound ; 64(6): 1099-1102, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37800663

RESUMO

Most primary cardiac tumors in dogs are located in the right atrium/atrial appendage, with hemangiosarcoma being the most common. The aims of this retrospective, case series were to describe outcomes for seven dogs with right atrial tumors treated with hypofractionated intensity-modulated radiotherapy and concurrent vinblastine and propranolol. One dog had a complete response, four dogs had partial responses and two dogs had stable disease after treatment. Effusions resolved in all dogs. Median progression-free survival was 290 days. Five dogs died from metastatic disease, one dog from unrelated neoplasia, and one dog is alive. Median overall survival was 326 days. Three dogs with confirmed hemangiosarcoma survived 244, 326, and 445 days. Two dogs developed clinically significant, but nonfatal, cardiac arrhythmias. One dog that received three courses of radiation had subclinical myocardial and arterial fibrosis at necropsy. Hypofractionated chemoradiotherapy was well tolerated and may provide clinical benefit in dogs with right atrial tumors.


Assuntos
Apêndice Atrial , Doenças do Cão , Hemangiossarcoma , Radioterapia de Intensidade Modulada , Cães , Animais , Radioterapia de Intensidade Modulada/veterinária , Estudos Retrospectivos , Apêndice Atrial/patologia , Hemangiossarcoma/terapia , Hemangiossarcoma/veterinária , Doenças do Cão/tratamento farmacológico , Doenças do Cão/radioterapia
5.
Vet Radiol Ultrasound ; 64(5): 789-797, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37582508

RESUMO

The toxicity criteria of the veterinary radiation therapy oncology group (VRTOG) version 2 guidelines are a substantial update to reflect significant advances in radiation oncology over the last three decades. Radiation therapy techniques provide precise and spatially accurate radiation delivery, which facilitates treating tumors in more anatomic locations and incorporating hypofractionated protocols. The purpose of this update is to aid radiation oncology teams in capturing and grading clinically relevant data that impacts the decision-making process in everyday practice and the assessment of clinical trials involving radiation therapy. A dedicated committee initially updated the criteria to include more anatomical sites and grades to characterize a broad spectrum of possible radiation-induced acute and late tissue changes. Through the revision process, which solicited and incorporated feedback from all radiation oncologists within the American College of Veterinary Radiology (ACVR) and specialists outside the ACVR, the authors endeavored to create a grading structure reflective of clinical decision-making in daily radiation oncology. The updated VRTOG v2 toxicity criteria guideline complements the updated Veterinary Cooperative Oncology Group-Common Terminology Criteria for Adverse Events (VCOG-CTCAE v2) guidelines. Because radiation oncology continues to progress rapidly, the VRTOG toxicity criteria should be regularly updated as adverse event data that will be collected following this update further informs the practice of radiation oncology.


Assuntos
Oncologia , Radioterapia (Especialidade) , Animais
6.
Vet Radiol Ultrasound ; 64(4): 768-774, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37335283

RESUMO

Canine optic pathway structures are often contoured on CT images, despite the difficulty of visualizing the optic pathway with CT using standard planes. The purpose of this prospective, analytical, diagnostic accuracy study was to examine the accuracy of optic pathway contouring by veterinary radiation oncologists (ROs) before and after training on optic plane contouring. Optic pathway contours used as the gold standard for comparison were created based on expert consensus from registered CT and MRI for eight dogs. Twenty-one ROs contoured the optic pathway on CT using their preferred method, and again following atlas and video training demonstrating contouring on the optic plane. The Dice similarity coefficient (DSC) was used to assess contour accuracy. A multilevel mixed model with random effects to account for repeated measures was used to examine DSC differences. The median DSC (5th and 95th percentile) before and after training was 0.31 (0.06, 0.48) and 0.41 (0.18, 0.53), respectively. The mean DSC was significantly higher after training compared with before training (mean difference = 0.10; 95% CI, 0.08-0.12; P < 0.001) across all observers and patients. DSC values were comparable to those reported (0.4-0.5) for segmentation of the optic chiasm and nerves in human patients. Contour accuracy improved after training but remained low, potentially due to the small optic pathway volumes. When registered CT-MRI images are not available, our study supports routine addition of an optic plane with specific window settings to improve segmentation accuracy in mesaticephalic dogs ≥11 kg.


Assuntos
Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Humanos , Animais , Cães , Estudos Prospectivos , Espécies Reativas de Oxigênio , Tomografia Computadorizada por Raios X/veterinária , Tomografia Computadorizada por Raios X/métodos , Imageamento por Ressonância Magnética/veterinária , Imageamento por Ressonância Magnética/métodos , Olho , Planejamento da Radioterapia Assistida por Computador/métodos , Planejamento da Radioterapia Assistida por Computador/veterinária
7.
J Neurosci ; 43(21): 3970-3984, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37019623

RESUMO

Endolysosomal defects in neurons are central to the pathogenesis of prion and other neurodegenerative disorders. In prion disease, prion oligomers traffic through the multivesicular body (MVB) and are routed for degradation in lysosomes or for release in exosomes, yet how prions impact proteostatic pathways is unclear. We found that prion-affected human and mouse brain showed a marked reduction in Hrs and STAM1 (ESCRT-0), which route ubiquitinated membrane proteins from early endosomes into MVBs. To determine how the reduction in ESCRT-0 impacts prion conversion and cellular toxicity in vivo, we prion-challenged conditional knockout mice (male and female) having Hrs deleted from neurons, astrocytes, or microglia. The neuronal, but not astrocytic or microglial, Hrs-depleted mice showed a shortened survival and an acceleration in synaptic derangements, including an accumulation of ubiquitinated proteins, deregulation of phosphorylated AMPA and metabotropic glutamate receptors, and profoundly altered synaptic structure, all of which occurred later in the prion-infected control mice. Finally, we found that neuronal Hrs (nHrs) depletion increased surface levels of the cellular prion protein, PrPC, which may contribute to the rapidly advancing disease through neurotoxic signaling. Taken together, the reduced Hrs in the prion-affected brain hampers ubiquitinated protein clearance at the synapse, exacerbates postsynaptic glutamate receptor deregulation, and accelerates neurodegeneration.SIGNIFICANCE STATEMENT Prion diseases are rapidly progressive neurodegenerative disorders characterized by prion aggregate spread through the central nervous system. Early disease features include ubiquitinated protein accumulation and synapse loss. Here, we investigate how prion aggregates alter ubiquitinated protein clearance pathways (ESCRT) in mouse and human prion-infected brain, discovering a marked reduction in Hrs. Using a prion-infection mouse model with neuronal Hrs (nHrs) depleted, we show that low neuronal Hrs is detrimental and markedly shortens survival time while accelerating synaptic derangements, including ubiquitinated protein accumulation, indicating that Hrs loss exacerbates prion disease progression. Additionally, Hrs depletion increases the surface distribution of prion protein (PrPC), linked to aggregate-induced neurotoxic signaling, suggesting that Hrs loss in prion disease accelerates disease through enhancing PrPC-mediated neurotoxic signaling.


Assuntos
Doenças Neurodegenerativas , Doenças Priônicas , Príons , Masculino , Feminino , Camundongos , Humanos , Animais , Príons/metabolismo , Proteínas Priônicas/metabolismo , Receptores de AMPA/metabolismo , Neurônios/metabolismo , Doenças Priônicas/metabolismo , Doenças Priônicas/patologia , Doenças Neurodegenerativas/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo
8.
PLoS One ; 18(3): e0282500, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36862650

RESUMO

For dogs with oral tumors, cervical lymph node (LN) metastasis alters treatment and prognosis. It is therefore prudent to make an accurate determination of the clinical presence (cN+ neck) or absence (cN0 neck) of metastasis prior to treatment. Currently, surgical LN extirpation with histopathology is the gold standard for a diagnosis of metastasis. Yet, recommendations to perform elective neck dissection (END) for staging are rare due to morbidity. Sentinel lymph node (SLN) mapping with indirect computed tomography lymphangiography (ICTL) followed by targeted biopsy (SLNB) is an alternative option to END. In this prospective study, SLN mapping followed by bilateral END of all mandibular LNs (MLNs) and medial retropharyngeal LNs (MRLNs) was performed in 39 dogs with spontaneously occurring oral neoplasia. A SLN was identified by ICTL in 38 (97%) dogs. Lymphatic drainage patterns were variable although most often the SLN was identified as a single ipsilateral MLN. In the 13 dogs (33%) with histopathologically confirmed LN metastasis, ICTL correctly identified the draining lymphocentrum in all (100%). Metastasis was confined to the SLN in 11 dogs (85%); 2 dogs (15%) had metastasis beyond the SLN ipsilaterally. Contrast enhanced CT features had good accuracy in predicting metastasis, with short axis measurements less than 10.5 mm most predictive. ICTL imaging features alone were unable to predict metastasis. Cytologic or histopathologic SLN sampling is recommended prior to treatment to inform clinical decision-making. This is the largest study to show potential clinical utility of minimally invasive ICTL for cervical LN evaluation in canine oral tumors.


Assuntos
Linfografia , Neoplasias Bucais , Cães , Animais , Linfografia/veterinária , Estudos Prospectivos , Metástase Linfática/diagnóstico por imagem , Neoplasias Bucais/diagnóstico por imagem , Neoplasias Bucais/veterinária , Tomografia Computadorizada por Raios X
9.
Brain Sci ; 14(1)2023 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-38248237

RESUMO

Cancer survivors experience cancer-related cognitive impairment (CRCI) secondary to treatment. Chemotherapy and radiation therapy independently contribute to cognitive dysfunction; however, the underlying mechanisms leading to dysfunction remain unclear. We characterized brain gene expression changes in a mouse model of CRCI to identify the mechanistic underpinnings. Eleven-to-twelve-week-old SKH1 mice were treated with doxorubicin (DOX), hindlimb radiation (RT), concurrent hindlimb radiation and doxorubicin (DOX-RT), or no treatment (control). Sixteen days following treatment, gene expression was measured from murine brains using the NanoString nCounter® glial profiling panel. Gene expression was normalized and compared between groups. No two groups shared the same expression pattern, and only Gnb1 and Srpr were upregulated in multiple treatment groups. Brains from DOX-treated mice had upregulated Atf2, Atp5b, Gnb1, Rad23b, and Srpr and downregulated Sirt5 expression compared to control brains. Brains from RT-treated mice demonstrated increased Abcg2 and Fgf2 and decreased C1qa and C1qb expression compared to control brains. Brains from DOX-RT-treated mice had upregulated Adar, E2f3, Erlec1, Gnb1, Srpr, Vim, and Pdgfra expression and downregulated Rock2 and Inpp5f expression compared to control brains. The gene expression changes demonstrated here highlight roles for neuronal transmission and oxidative stress in the pathogenesis of doxorubicin-related CRCI and inflammation in RT-related CRCI.

10.
Neurobiol Dis ; 172: 105834, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35905927

RESUMO

Synapse dysfunction and loss are central features of neurodegenerative diseases, caused in part by the accumulation of protein oligomers. Amyloid-ß, tau, prion, and α-synuclein oligomers bind to the cellular prion protein (PrPC), resulting in the activation of macromolecular complexes and signaling at the post-synapse, yet the early signaling events are unclear. Here we sought to determine the early transcript and protein alterations in the hippocampus during the pre-clinical stages of prion disease. We used a transcriptomic approach focused on the early-stage, prion-infected hippocampus of male wild-type mice, and identify immediate early genes, including the synaptic activity response gene, Arc/Arg3.1, as significantly upregulated. In a longitudinal study of male, prion-infected mice, Arc/Arg-3.1 protein was increased early (40% of the incubation period), and by mid-disease (pre-clinical), phosphorylated AMPA receptors (pGluA1-S845) were increased and metabotropic glutamate receptors (mGluR5 dimers) were markedly reduced in the hippocampus. Notably, sporadic Creutzfeldt-Jakob disease (sCJD) post-mortem cortical samples also showed low levels of mGluR5 dimers. Together, these findings suggest that prions trigger an early Arc response, followed by an increase in phosphorylated GluA1 and a reduction in mGluR5 receptors.


Assuntos
Síndrome de Creutzfeldt-Jakob , Príons , Peptídeos beta-Amiloides/metabolismo , Animais , Síndrome de Creutzfeldt-Jakob/metabolismo , Hipocampo/metabolismo , Estudos Longitudinais , Masculino , Camundongos , Príons/metabolismo
11.
Vet Radiol Ultrasound ; 63(2): 224-233, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34904326

RESUMO

Postoperative radiation therapy (RT) may be beneficial for dogs with anal sac apocrine gland adenocarcinoma (ASAC). Clinically significant late toxicities have been reported in up to 65% of dogs with perianal tumors following non-conformal definitive RT, particularly when fractions of 3 Gy or higher are prescribed. The primary objective of this prospective, descriptive study was to evaluate tolerability of a novel 3D conformal RT (3DCRT) protocol in a group of dogs. Dogs with ASAC were prospectively enrolled if clients elected RT following surgery. The planning target volume was prescribed 50 Gy in 2.5 Gy fractions using 6 MV photons and administered over 26 days. Early and late radiation toxicities were graded according to standardized criteria. Thirteen dogs were initially enrolled but 1 was excluded due to a high risk of anesthesia-related mortality. Seven dogs presented with early stage disease. Median follow up time was 771 days (91-2223). Transient grade 3 dermatitis and anusitis developed in all dogs, with resolution within 4 weeks. Two dogs developed transient grade 2 late colitis. Locoregional failure in the irradiated field was documented in one dog at 738 days. All-cause median survival time was 771 days (95% confidence interval: 510 â†’ 2223 days). Findings indicated that this fractionation may be safely administered to the canine anus and pelvic canal using 3DCRT, although acute toxicity should be anticipated. Further prospective studies are needed in order to confirm long-term tolerability and efficacy.


Assuntos
Adenocarcinoma , Sacos Anais , Doenças do Cão , Lesões por Radiação , Radioterapia Conformacional , Adenocarcinoma/radioterapia , Adenocarcinoma/veterinária , Animais , Glândulas Apócrinas , Doenças do Cão/radioterapia , Cães , Lesões por Radiação/veterinária , Dosagem Radioterapêutica/veterinária , Radioterapia Conformacional/efeitos adversos , Radioterapia Conformacional/métodos , Radioterapia Conformacional/veterinária
12.
Front Behav Neurosci ; 16: 1067298, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36699654

RESUMO

Introduction: Cancer survivors are increasingly diagnosed with a syndrome of neurocognitive dysfunction termed cancer-related cognitive impairment (CRCI). Chemotherapy and radiation therapy have been implicated in CRCI; however, its underlying pathogenesis remains unclear, hindering effective prevention or treatment. Methods: We used the hairless strain SKH1 (11-12-week-old) and treated the mice with radiation to the right hindlimb, doxorubicin (a chemotherapy agent), concurrent radiation, and doxorubicin, or no treatment (control). Neurocognition was evaluated via standardized behavioral testing following treatment. Mice were subsequently humanely euthanized, and plasma and brains were collected to identify inflammatory changes. Results: Mice treated with radiation, doxorubicin, or both radiation and doxorubicin demonstrated equivalent hippocampal dependent memory deficits and significant increases in activated microglia and astrocytes compared to control mice. Doxorubicin-treated mice had significantly increased plasma IL-6 and failed to gain weight compared to control mice over the study period. Discussion: This study demonstrates that non-brain directed radiation induces both gliosis and neurocognitive deficits. Moreover, this work presents the first characterization of SKH1 mice as a relevant and facile animal model of CRCI. This study provides a platform from which to build further studies to identify potential key targets that contribute to CRCI such that strategies can be developed to mitigate unintended neuropathologic consequences associated with anticancer treatment.

13.
Vet Radiol Ultrasound ; 62(6): 711-719, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34448312

RESUMO

Tumor heterogeneity is a well-established marker of biologically aggressive neoplastic processes and is associated with local recurrence and distant metastasis. Quantitative analysis of CT textural features is an indirect measure of tumor heterogeneity and therefore may help predict malignant disease. The purpose of this retrospective, secondary analysis study was to quantitatively evaluate CT heterogeneity in dogs with histologically confirmed liver masses to build a predictive model for malignancy. Forty dogs with liver tumors and corresponding histopathologic evaluation from a previous prospective study were included. Triphasic image acquisition was standardized across dogs and whole liver and liver mass were contoured on each precontrast and delayed postcontrast dataset. First-order and second-order indices were extracted from contoured regions. Univariate analysis identified potentially significant indices that were subsequently used for top-down model construction. Multiple quadratic discriminatory models were constructed and tested, including individual models using both postcontrast and precontrast whole liver or liver mass volumes. The best performing model utilized the CT features voxel volume and uniformity from postcontrast mass contours; this model had an accuracy of 0.90, sensitivity of 0.67, specificity of 1.0, positive predictive value of 1.0, negative predictive value of 0.88, and precision of 1.0. Heterogeneity indices extracted from delayed postcontrast CT hepatic mass contours were more informative about tumor type compared to indices from whole liver contours, or from precontrast hepatic mass and whole liver contours. Results demonstrate that CT radiomic feature analysis may hold clinical utility as a noninvasive method of predicting hepatic malignancy and may influence diagnostic or therapeutic approaches.


Assuntos
Doenças do Cão , Neoplasias Hepáticas , Animais , Doenças do Cão/diagnóstico por imagem , Cães , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/veterinária , Aprendizado de Máquina , Valor Preditivo dos Testes , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/veterinária
14.
PLoS One ; 16(8): e0256139, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34403435

RESUMO

Quantitative analysis of computed tomography (CT) radiomic features is an indirect measure of tumor heterogeneity, which has been associated with prognosis in human lung carcinoma. Canine lung tumors share similar features to human lung tumors and serve as a model in which to investigate the utility of radiomic features in differentiating tumor type and prognostication. The purpose of this study was to correlate first-order radiomic features from canine pulmonary tumors to histopathologic characteristics and outcome. Disease-free survival, overall survival time and tumor-specific survival were calculated as days from the date of CT scan. Sixty-seven tumors from 65 dogs were evaluated. Fifty-six tumors were classified as primary pulmonary adenocarcinomas and 11 were non-adenocarcinomas. All dogs were treated with surgical resection; 14 dogs received adjuvant chemotherapy. Second opinion histopathology in 63 tumors confirmed the histologic diagnosis in all dogs and further characterized 53 adenocarcinomas. The median overall survival time was longer (p = 0.004) for adenocarcinomas (339d) compared to non-adenocarcinomas (55d). There was wide variation in first-order radiomic statistics across tumors. Mean Hounsfield units (HU) ratio (p = 0.042) and median mean HU ratio (p = 0.042) were higher in adenocarcinomas than in non-adenocarcinomas. For dogs with adenocarcinoma, completeness of excision was associated with overall survival (p<0.001) while higher mitotic index (p = 0.007) and histologic score (p = 0.037) were associated with shorter disease-free survival. CT-derived tumor variables prognostic for outcome included volume, maximum axial diameter, and four radiomic features: integral total, integral total mean ratio, total HU, and max mean HU ratio. Tumor volume was also significantly associated with tumor invasion (p = 0.044). Further study of radiomic features in canine lung tumors is warranted as a method to non-invasively interrogate CT images for potential predictive and prognostic utility.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Tomografia Computadorizada de Emissão/métodos , Adenocarcinoma/patologia , Animais , Carcinoma Pulmonar de Células não Pequenas/patologia , Bases de Dados Factuais , Bases de Dados Genéticas , Intervalo Livre de Doença , Cães , Feminino , Pulmão/patologia , Neoplasias Pulmonares/veterinária , Masculino , Prognóstico , Estudos Retrospectivos , Tomografia Computadorizada de Emissão/veterinária , Tomografia Computadorizada por Raios X/métodos , Carga Tumoral
15.
Sci Rep ; 11(1): 9553, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33953285

RESUMO

Lung is a dose-limiting organ in radiotherapy. This may limit tumour control when effort is made in planning to limit the likelihood of radiation-induced lung injury (RILI). Understanding the factors that dictate susceptibility to radiation-induced pulmonary fibrosis will aid in the prevention and management of RILI, and may lead to more effective personalized radiotherapy treatment. As the interaction of regional and organ-level responses may shape the chronic consequences of RILI, we sought to characterise both aspects of the response in an ovine model. A defined volume of left pulmonary parenchyma was prescribed 5 fractions of 6 Gy within 14 days while the contralateral lung dose was constrained. Radiographic changes via computed tomography (CT) were documented to define differences in radio-exposed lung relative to non-exposed lung at d21, d63 and d171 (n = 2), and at d21, d147 and d227 (n = 2). Gross and histologic lung changes were evaluated in samples derived at necropsy examination to define the chronic pulmonary response to radiation. Irradiated lung demonstrated reduced radio-density and increased homogeneity as evidenced from texture based radiomic feature analysis, relative to the control lung. At necropsy, the radiation field was readily defined by pallor on the pleural surface, which was also evident on the cut surface of fixed lung specimens. The degree and homogeneity of pallor reflected the sparse presence of erythrocytes in alveolar septal capillaries of radiation-exposed lung. These changes contrasted with dilated and congested microvasculature in the contralateral control lung. Referencing data to measurements made in control lung volumes of sheep experiencing acute RILI indicated that interstitial collagen continues to deposit in the radio-exposed lung field. Overall lung vascularity increased during the chronic response, as evidenced by increased expression of endothelial cell marker (CD31); however, vascularity was consistently decreased in irradiated lung and was negatively correlated with lung collagen. Other organ-level responses included increased expression of alpha smooth muscle actin (ASMA), increased numbers of proliferating cells (Ki67 positive), and cells expressing the dendritic cell-lysosomal associated membrane protein (DC-LAMP) antigen. The chronic response to RILI in this model is effected at both the whole organ and local lung level. Whilst the long-term consequences of exposure to radiation involved the continued deposition of collagen in the radiation field, organ-level responses also included increased vascularization and increased expression of ASMA, Ki67 and DC-LAMP. Interrupting the interplay between these aspects may influence susceptibility to pulmonary fibrosis after radiotherapy. We advocate for the importance of large animal model systems in pursuing these opportunities to target local, organ-level and systemic mechanisms in parallel within the same subject over time.


Assuntos
Pulmão/efeitos da radiação , Neoplasias/radioterapia , Pneumonite por Radiação/patologia , Radioterapia/efeitos adversos , Animais , Modelos Animais de Doenças , Feminino , Pulmão/patologia , Ovinos
16.
Pediatr Crit Care Med ; 22(12): 1074-1082, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34034306

RESUMO

OBJECTIVES: To assess the prevalence of relationship distress and burnout among PICU nurses. DESIGN: Cross-sectional, web-based survey. SETTING: Pediatric intensive care nursing practices in the United States. SUBJECTS: Pediatric intensive care nurses. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 254 pediatric intensive care nurses in the United States completed the survey consisting of demographic data, practice, and personal characteristics, Revised Dyadic Adjustment Scale, and modified Maslach Burnout Inventory. Relationship distress in consensus was noted in 45.6% of participants, and 26.3% reported distress in relationship satisfaction. Moderate to high burnout was reported by 65% nurses in the emotional exhaustion domain, 43% in depersonalization, and 27% of nurses reported low personal accomplishment. A significant difference in relationship satisfaction was found among nurses identified in different domains of burnout, showing that nurses who scored higher in depersonalization also reported higher distress in relationship satisfaction (p = 0.045). Interestingly, nurses who reported high personal accomplishment (thereby less burnout) reported higher distress in relationship consensus (p = 0.015). The difference in the satisfaction subscale between different age groups was significant, suggesting distress in satisfaction among nurses over the age of 40 (p = 0.004). Comparison of nurses actively involved in marriage counseling with those not actively involved in marriage counseling demonstrated a significant difference in relationship consensus (p = 0.046; odds ratio = 2.46; 95% CI, 0.99-6.06) and satisfaction (p = 0.004; odds ratio = 3.26; 95% CI, 1.42-7.47), suggesting an association between higher relationship distress and counseling. CONCLUSIONS: This study reflects the prevalence of relationship distress and its association with burnout and other practice and personal factors among PICU nurses. Nurses with high depersonalization experienced significantly higher distress in relationship satisfaction, and nurses who reported high personal satisfaction had significantly higher distress in relationship consensus.


Assuntos
Esgotamento Profissional , Enfermeiras e Enfermeiros , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/psicologia , Criança , Cuidados Críticos/psicologia , Estudos Transversais , Humanos , Satisfação no Emprego , Inquéritos e Questionários
17.
J Am Vet Med Assoc ; 258(8): 877-882, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33825539

RESUMO

CASE DESCRIPTION: A 12-year-old spayed female Jack Russell Terrier was presented with pollakiuria and stranguria. CLINICAL FINDINGS: Transitional cell carcinoma (TCC) of the urinary bladder trigone and urethra was diagnosed via CT, cystoscopic, and histologic examinations. Azotemia developed 2 weeks following diagnosis, secondary to bilateral ureteral obstruction. TREATMENT AND OUTCOME: Percutaneous antegrade ureteral stenting was unsuccessful; therefore, a subcutaneous ureteral bypass (SUB) device with 2 nephrostomy and 1 cystostomy catheters was surgically placed. Two months following placement of the SUB device, the dog developed a firm, multilobulated cutaneous mass at the site of the subcutaneous access port of the SUB device. Results of cytologic examination of cells aspirated from the mass were consistent with TCC. Within 1 month of confirmation of TCC of the cutaneous mass, the mass was ulcerated and infected, and the dog was euthanized because of signs of pain and perceived poor quality of life. CLINICAL RELEVANCE: Seeding of neoplastic cells is a known complication of needle aspiration or biopsy or surgery in people and dogs with carcinomas. The occurrence of TCC at the SUB port site suggested caution with the placement of a SUB device in dogs with obstructive TCC.


Assuntos
Carcinoma de Células de Transição , Doenças do Cão , Obstrução Ureteral , Animais , Carcinoma de Células de Transição/cirurgia , Carcinoma de Células de Transição/veterinária , Doenças do Cão/etiologia , Doenças do Cão/cirurgia , Cães , Feminino , Masculino , Qualidade de Vida , Obstrução Ureteral/cirurgia , Obstrução Ureteral/veterinária , Bexiga Urinária
18.
Lancet Glob Health ; 9(4): e489-e551, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33607016
19.
Curr Oncol ; 28(1): 509-522, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33467402

RESUMO

BACKGROUND: Approximately 2-6% of endometrial cancers (ECs) are due to Lynch Syndrome (LS), a cancer predisposition syndrome caused by germline pathogenic variants (PVs) affecting the DNA mismatch repair (MMR) pathway. Increasingly, universal tissue-based screening of ECs has been proposed as an efficient and cost-effective way to identify families with LS, though few studies have been published on Canadian cohorts. The purpose of this study was to evaluate the feasibility and overall performance of a universal immunohistochemistry (IHC) screening program for women with EC within a single Canadian university hospital centre. METHODS AND RESULTS: From 1 October 2015 to 31 December 2017, all newly diagnosed ECs (n = 261) at our centre were screened for MMR protein deficiency by IHC. MMR deficiency was noted in 69 tumours (26.4%), among which 53 had somatic MLH1 promoter hypermethylation and were considered "screen-negative". The remaining MMR-deficient cases (n = 16) were considered "screen-positive" and were referred for genetic counselling and testing. Germline PVs were identified in 12/16 (75%). One additional PV was identified in a screen-negative individual who was independently referred to the Genetics service. This corresponds to an overall LS frequency of 5.0% among unselected women with EC, and 6.4% among women diagnosed under age 70 years. Our algorithm detected MMR gene pathogenic variants in 4.6% and 6.2% of unselected individuals and individuals under age 70 years, respectively. Four germline PVs (30.8%) were identified in individuals who did not meet any traditional LS screening criteria. CONCLUSIONS: Universal IHC screening for women with EC is an effective and feasible method of identifying individuals with LS in a Canadian context.


Assuntos
Reparo de Erro de Pareamento de DNA , Neoplasias do Endométrio , Idoso , Canadá/epidemiologia , Metilação de DNA , Reparo de Erro de Pareamento de DNA/genética , Detecção Precoce de Câncer , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/epidemiologia , Neoplasias do Endométrio/genética , Feminino , Humanos
20.
J Trauma Nurs ; 27(6): 319-326, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33156246

RESUMO

BACKGROUND: Burnout is a psychological syndrome resulting from repeated stressors experienced in the workplace that centers on emotional exhaustion, detachment from the job, and a sense of ineffectiveness. It has been previously demonstrated that burnout exists in the health care workforce, but there has been limited investigation of burnout in nurses who primarily provide care for patients who have been traumatically injured. The purpose of this study was to explore factors associated with burnout reported by trauma nurses. METHODS: This was a secondary analysis of a cross-sectional survey distributed at a large, academic Level I trauma center that serves both adult and pediatric patients. For this analysis, only the Burnout subscale of the Professional Quality of Life scale Version 5 (ProQOL) was used. Multivariate hierarchical regression was used to determine factors associated with burnout reported by trauma nurses. RESULTS: Protective factors included being female, being married, and better quality of sleep. Risk factors included having a mental health diagnosis and working with adult populations. CONCLUSIONS: These results provide an important contribution to the burnout risk profile for trauma nurses and may provide insight into future investigations as well as development and testing of tailored interventions to mitigate burnout in trauma nurses.


Assuntos
Esgotamento Profissional , Enfermagem em Ortopedia e Traumatologia , Adulto , Esgotamento Psicológico , Criança , Estudos Transversais , Feminino , Humanos , Satisfação no Emprego , Enfermeiras e Enfermeiros , Qualidade de Vida , Inquéritos e Questionários
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