Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 356
Filtrar
1.
J Clin Oncol ; : JCO2400022, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39365957

RESUMO

PURPOSE: NRG-RTOG0617 demonstrated a detrimental effect of uniform high-dose radiation in stage III non-small cell lung cancer. NRG-RTOG1106/ECOG-ACRIN6697 (ClinicalTrials.gov identifier: NCT01507428), a randomized phase II trial, studied whether midtreatment 18F-fluorodeoxyglucose position emission tomography/computed tomography (FDG-PET/CT) can guide individualized/adaptive dose-intensified radiotherapy (RT) to improve and predict outcomes in patients with this disease. MATERIALS AND METHODS: Patients fit for concurrent chemoradiation were randomly assigned (1:2) to standard (60 Gy/30 fractions) or FDG-PET-guided adaptive treatment, stratified by substage, primary tumor size, and histology. All patients had midtreatment FDG-PET/CT; adaptive arm patients had an individualized, intensified boost RT dose to residual metabolically active areas. The primary therapeutic end point was 2-year centrally reviewed freedom from local-regional progression (FFLP), defined as no progression in or near the planning target volume and/or regional nodes. FFLP was analyzed on a modified intent-to-treat population at a one-sided Z-test significance level of 0.15. The primary imaging end point was centrally reviewed change in SUVpeak from baseline to midtreatment; its association with FFLP was assessed using the two-sided Wald test on the basis of Cox regression. RESULTS: Of 138 patients enrolled, 127 were eligible. Adaptive-arm patients received a mean 71 Gy in 30 fractions, with mean lung dose 17.9 Gy. There was no significant difference in centrally reviewed 2-year FFLP (59.5% and 54.6% in standard and adaptive arms; P = .66). There were no significant differences in protocol-specified grade 3 toxicities, survival, or progression-free survival (P > .4). Median SUVpeak and metabolic tumor volume (MTV) in the adaptive arm decreased 49% and 54%, from pre-RT to mid-RT PET. However, ΔSUVpeak and ΔMTV were not associated with FFLP (hazard ratios, 0.997; P = .395 and .461). CONCLUSION: Midtreatment PET-adapted RT dose escalation as given in this study was safe and feasible but did not improve efficacy outcomes.

2.
Shock ; 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39293062

RESUMO

ABSTRACT: In recent years, it has become apparent that fibrinolytic dysfunction and endotheliopathy develop in up to 40% of patients during the first hours following thermal injury and are associated with poor outcomes and increased resuscitation requirements. Rapidly following burn injury, the fibrinolytic system is activated, with activation generally greater with increased severity of injury. Very high plasma concentrations of plasmin-antiplasmin complex (marker of activation), have been associated with mortality. Patients display hyperfibrinolytic, physiologic/normal or hypofibrinolytic/fibrinolytic shutdown phenotypes, as assessed by viscoelastic assay. Phenotypes change in over 50% of patients during the acute burn resuscitation period, with some patterns (maladaptive) associated with increased mortality risk and others (adaptive, trending toward the physiologic phenotype) associated with survival. Endotheliopathy, as reflected in elevated plasma concentrations of syndecan-1 has also been associated with increased mortality. Here we review the incidence and effects of these responses after burn injury and explore mechanisms and potential interactions with the early inflammatory response. Available data from burn and non-burn trauma suggest that the fibrinolytic, endothelial, and inflammatory systems interact extensively and that dysregulation in one may exacerbate dysregulation in the others. This raises the possibility that successful treatment of one may favorably impact the others.

3.
Artigo em Inglês | MEDLINE | ID: mdl-39284532

RESUMO

PURPOSE: Radiation-induced pulmonary fibrosis (RIPF) is a potentially serious and disabling late complication of radiation therapy. Monitoring RIPF progression is challenging due to the absence of early detection tools and the difficulty in distinguishing RIPF from other lung diseases using standard imaging methods. In the lungs, integrin αvß6 is crucial in the development of RIPF, acting as a significant activator of transforming growth factor ß after radiation injury. This study aimed to investigate integrin αvß6-targeted positron emission tomography (PET) imaging ([64Cu]Cu-αvß6-BP) to study RIPF development in vivo. METHODS AND MATERIALS: We used a focal RIPF model (70 Gy delivered focally to a 3 mm spot in the lung) and a whole lung RIPF model (14 Gy delivered to the whole lung) in adult C57BL/6J mice. Small animal PET/computed tomography images were acquired 1 hour postinjection of 11.1 MBq of [64Cu]Cu-αvß6-BP. Animals were imaged for 8 weeks in the focal RIPF model and 6 months in the whole lung RIPF model. Immunohistochemistry for integrin αvß6 and trichrome staining were performed. RESULTS: In the focal RIPF model, there was focal uptake of [64Cu]Cu-αvß6-BP in the irradiated region at week 4 that progressively increased at weeks 6 and 8. In the whole lung RIPF model, minimal uptake of the probe was observed at 4 months post-radiation therapy, which significantly increased at months 5 and 6. Expression of integrin αvß6 was validated histologically by immunohistochemistry in both models. CONCLUSIONS: Integrin αvß6-targeted PET imaging using [64Cu]Cu-αvß6-BP can serve as a useful tool to identify RIPF in vivo.

4.
Nat Commun ; 15(1): 6626, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103353

RESUMO

N-Myc is a key driver of neuroblastoma and neuroendocrine prostate cancer (NEPC). One potential way to circumvent the challenge of undruggable N-Myc is to target the protein homeostasis (proteostasis) system that maintains N-Myc levels. Here, we identify heat shock protein 70 (HSP70) as a top partner of N-Myc, which binds a conserved "SELILKR" motif and prevents the access of E3 ubiquitin ligase, STIP1 homology and U-box containing protein 1 (STUB1), possibly through steric hindrance. When HSP70's dwell time on N-Myc is increased by treatment with the HSP70 allosteric inhibitor, STUB1 is in close proximity with N-Myc and becomes functional to promote N-Myc ubiquitination on the K416 and K419 sites and forms polyubiquitination chains linked by the K11 and K63 sites. Notably, HSP70 inhibition significantly suppressed NEPC tumor growth, increased the efficacy of aurora kinase A (AURKA) inhibitors, and limited the expression of neuroendocrine-related pathways.


Assuntos
Proteínas de Choque Térmico HSP70 , Neoplasias da Próstata , Proteostase , Ubiquitina-Proteína Ligases , Ubiquitinação , Masculino , Humanos , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/genética , Proteínas de Choque Térmico HSP70/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitinação/efeitos dos fármacos , Linhagem Celular Tumoral , Animais , Aurora Quinase A/metabolismo , Aurora Quinase A/genética , Aurora Quinase A/antagonistas & inibidores , Proteína Proto-Oncogênica N-Myc/metabolismo , Proteína Proto-Oncogênica N-Myc/genética , Camundongos , Carcinoma Neuroendócrino/metabolismo , Carcinoma Neuroendócrino/genética , Carcinoma Neuroendócrino/tratamento farmacológico , Carcinoma Neuroendócrino/patologia , Tumores Neuroendócrinos/metabolismo , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/patologia
5.
Radiother Oncol ; 200: 110473, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39137832

RESUMO

BACKGROUND AND PURPOSE: A retrospective evaluation of dosimetric predictors and leveraged dose-volume data for gastrointestinal (GI) toxicities for locally-advanced pancreatic cancer (LAPC) treated with daily stereotactic MRI-guided online-adaptive radiotherapy (SMART). MATERIALS AND METHODS: 147 patients with LAPC were treated with SMART at our institution between 2018 and 2021. Patients were evaluated using CTCAE V5.0 for RT-related acute (≤3 months) and late (>3 months) toxicities. Each organ at risk (OAR) was matched to a ≥ grade 2 (Gr2+) toxicity endpoint composite group. A least absolute shrinkage selector operator regression model was constructed by dose-volumes per OAR to account for OAR multicollinearity. A receiver operator curve (ROC) analysis was performed for the combined averages of significant toxicity groups to identify critical volumes per dose levels. RESULTS: 18 of 147 patients experienced Gr2+ GI toxicity. 17 Gr2+ duodenal toxicities were seen; the most significant predictor was a V33Gy odds ratio (OR) of 1.69 per cc (95 % CI 1.14-2.88). 17 Gr2+ small bowel (SB) toxicities were seen; the most significant predictor was a V33Gy OR of 1.60 per cc (95 % CI 1.01-2.53). The AUC was 0.72 for duodenum and SB. The optimal duodenal cut-point was 1.00 cc (true positive (TP): 17.8 %; true negative (TN); 94.9 %). The SB cut-point was 1.75 cc (TP: 16.7 %; TN: 94.3 %). No stomach or large bowel dose toxicity predictors were identified. CONCLUSIONS: For LAPC treated with SMART, the dose-volume threshold of V33Gy for duodenum and SB was associated with Gr2+ toxicities. These metrics can be utilized to guide future dose-volume constraints for patients undergoing upper abdominal SBRT.


Assuntos
Adenocarcinoma , Órgãos em Risco , Neoplasias Pancreáticas , Radiocirurgia , Dosagem Radioterapêutica , Radioterapia Guiada por Imagem , Humanos , Neoplasias Pancreáticas/radioterapia , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Estudos Retrospectivos , Radioterapia Guiada por Imagem/métodos , Radioterapia Guiada por Imagem/efeitos adversos , Adenocarcinoma/radioterapia , Adenocarcinoma/patologia , Órgãos em Risco/efeitos da radiação , Radiocirurgia/métodos , Radiocirurgia/efeitos adversos , Lesões por Radiação/etiologia , Idoso de 80 Anos ou mais , Adulto , Imageamento por Ressonância Magnética/métodos , Planejamento da Radioterapia Assistida por Computador/métodos
6.
Heart Rhythm ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39032525

RESUMO

Stereotactic arrhythmia radioablation (STAR) is a noninvasive treatment of refractory ventricular tachycardia (VT). In this study, we aimed to systematically review prospective trials on STAR and pool harmonized outcome measures in a meta-analysis. After registration in the International Prospective Register of Systematic Reviews (PROSPERO: CRD42023439666), we searched OVID Medline, OVID Embase, Web of Science Core Collection, the Cochrane Central Register of Controlled Trials, and Google Scholar on November 9, 2023, to identify reports describing results of prospective trials evaluating STAR for VT. Risk of bias was assessed using the Risk Of Bias In Non-randomized Studies of Interventions tool. Meta-analysis was performed using generalized linear mixed models. We identified 10 prospective trials in which 82 patients were treated with STAR between 2016 and 2022. The 90-day rate of treatment-related grade ≥3 adverse events was 0.10 (95% confidence interval [CI] 0.04-0.2). The proportions of patients achieving given VT burden reductions were 0.61 (95% CI 0.45-0.74) for ≥95%, 0.80 (95% CI 0.62-0.91) for ≥75%, and 0.9 (95% CI 0.77-0.96) for ≥50% in 63 evaluable patients. The 1-year overall survival rate was 0.73 (95% CI 0.61-0.83) in 81 patients, 1-year freedom from recurrence was 0.30 (95% CI 0.16-0.49) in 61 patients, and 1-year recurrence-free survival was 0.21 in 60 patients (95% CI 0.08-0.46). Limitations include methodological heterogeneity across studies and moderate to significant risk of bias. In conclusion, STAR is a promising treatment method, characterized by moderate toxicity. We observed 1-year mortality of ≈27% in this population of critically ill patients suffering from refractory VT. Most patients experience a significant reduction in VT burden; however, 1-year recurrence rates are high. STAR should still be considered an investigational approach and recommended to patients primarily within the context of prospective trials.

7.
Cureus ; 16(6): e62906, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39040774

RESUMO

Stereotactic body radiotherapy (SBRT) to the central and ultra-central thorax is associated with infrequent but potentially serious adverse events. Adaptive SBRT, which provides more precise treatment planning and inter-fraction motion management, may allow the delivery of ablative doses to ultra-central tumors with effective local control and improved toxicity profiles. Herein, we describe the first reported case of cone beam computed tomography (CBCT)-guided stereotactic adaptive radiotherapy (CT-STAR) in the treatment of ultra-central non-small cell lung cancer (NSCLC) in a prospective clinical trial (NCT05785845). An 80-year-old man with radiographically diagnosed early-stage NSCLC presented for definitive management of an enlarging ultra-central lung nodule. He was prescribed 55 Gy in five fractions with CT-STAR. A simulation was performed using four-dimensional CT, and patients were planned for treatment at end-exhale breath-hold. Treatment plans were generated using a strict isotoxicity approach, which prioritized organ at risk (OAR) constraints over target coverage. During treatment, daily CBCTs were acquired and used to generate adapted contours and treatment plans based on the patient's anatomy-of-the-day, all while the patient was on the treatment table. The initial and adapted plans were compared using dose-volume histograms, and the superior plan was selected for treatment. The adapted plan was deemed superior and used for treatment in three out of five fractions. The adapted plan provided improved target coverage in two fractions and resolved an OAR hard constraint violation in one fraction. We report the successful treatment of a patient with ultra-central NSCLC utilizing CT-STAR. This case report builds on previously published in silico data to support the viability and dosimetric advantages of CT-STAR in the ablative treatment of this challenging tumor location. Further data are needed to confirm the toxicity and efficacy of this technique.

8.
Technol Cancer Res Treat ; 23: 15330338241262610, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39051529

RESUMO

PURPOSE: A daily quality assurance (QA) check in proton therapy is ensuring that the range of each proton beam energy in water is accurate to 1 mm. This is important for ensuring that the tumor is adequately irradiated while minimizing damage to surrounding healthy tissue. It is also important to verify the total charge collected against the beam model. This work proposes a time-efficient method for verifying the range and total charge of proton beams at different energies using a multilayer Faraday collector (MLFC). METHODS: We used an MLFC-128-250 MeV comprising 128 layers of thin copper foils separated by thin insulating KaptonTM layers. Protons passing through the collector induce a charge on the metallic foils, which is integrated and measured by a multichannel electrometer. The charge deposition on the foils provides information about the beam range. RESULTS: Our results show that the proton beam range obtained using MLFC correlates closely with the range obtained from commissioning water tank measurements for all proton energies. Upon applying a range calibration factor, the maximum deviation is 0.4 g/cm2. The MLFC range showed no dependence on the number of monitor units and the source-to-surface distance. Range measurements collected over multiple weeks exhibited stability. The total charge collected agrees closely with the theoretical charge from the treatment planning system beam model for low- and mid-range energies. CONCLUSIONS: We have calibrated and commissioned the use of the MLFC to easily verify range and total charge of proton beams. This tool will improve the workflow efficiency of the proton QA.


Assuntos
Terapia com Prótons , Terapia com Prótons/métodos , Terapia com Prótons/instrumentação , Humanos , Dosagem Radioterapêutica , Prótons , Planejamento da Radioterapia Assistida por Computador/métodos , Calibragem , Garantia da Qualidade dos Cuidados de Saúde , Radiometria/métodos , Neoplasias/radioterapia
9.
Br J Clin Pharmacol ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858224

RESUMO

Infants bear a significant malaria burden but are usually excluded from participating in early dose optimization studies that inform dosing regimens of antimalarial therapy. Unlike older children, infants' exclusion from early-phase trials has resulted in limited evidence to guide accurate dosing of antimalarial treatment for uncomplicated malaria or malaria-preventive treatment in this vulnerable population. Subsequently, doses used in infants are often extrapolated from older children or adults, with the potential for under- or overdosing. Population pharmacokinetic-pharmacodynamic (PK-PD) modelling, a quantitative methodology that applies mathematical and statistical techniques, can aid the design of clinical studies in infants that collect sparse pharmacokinetic data as well as support the analysis of such data to derive optimized antimalarial dosing in this complex and at-risk yet understudied subpopulation. In this review, we reflect on what PK-PD modelling can do in programmatic settings of most malaria-endemic areas and how it can be used to inform antimalarial dose optimization for preventive and curative treatment of uncomplicated malaria in infants. We outline key developmental physiological changes that affect drug exposure in early life, the challenges of conducting dose optimization studies in infants, and examples of how PK-PD modelling has previously informed antimalarial dose optimization in this subgroup. Additionally, we discuss the limitations and gaps of PK-PD modelling when used for dose optimization in infants. To utilize modelling well, there is a need to generate useful, sparse, PK and PD data in this subpopulation to inform antimalarial optimal dosing in infancy.

10.
bioRxiv ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38496556

RESUMO

Potential systemic factors contributing to aging-associated breast cancer (BC) remain elusive. Here, we reveal that the polyploid giant cells (PGCs) that contain more than two sets of genomes prevailing in aging and cancerous tissues constitute 5-10% of healthy female bone marrow mesenchymal stromal cells (fBMSCs). The PGCs can repair DNA damage and stimulate neighboring cells for clonal expansion. However, dying PGCs in advanced-senescent fBMSCs can form "spikings" which are then separated into membraned mtDNA-containing vesicles (Senescent PGC-Spiking Bodies; SPSBs). SPSB-phagocytosed macrophages accelerate aging with diminished clearance on BC cells and protumor M2 polarization. SPSB-carried mitochondrial OXPHOS components are enriched in BC of elder patients and associated with poor prognosis. SPSB-incorporated breast epithelial cells develop aggressive characteristics and PGCs resembling the polyploid giant cancer cells (PGCCs) in clonogenic BC cells and cancer tissues. These findings highlight an aging BMSC-induced BC risk mediated by SPSB-induced macrophage dysfunction and epithelial cell precancerous transition. SIGNIFICANCE: Mechanisms underlying aging-associated cancer risk remain unelucidated. This work demonstrates that polyploid giant cells (PGCs) in bone marrow mesenchymal stromal cells (BMSCs) from healthy female bone marrow donors can boost neighboring cell proliferation for clonal expansion. However, the dying-senescent PGCs in the advanced-senescent fBMSCs can form "spikings" which are separated into mitochondrial DNA (mtDNA)-containing spiking bodies (senescent PGC-spiking bodies; SPSBs). The SPSBs promote macrophage aging and breast epithelial cell protumorigenic transition and form polyploid giant cancer cells. These results demonstrate a new form of ghost message from dying-senescent BMSCs, that may serve as a systemic factor contributing to aging-associated immunosuppression and breast cancer risk.

12.
J Appl Clin Med Phys ; 25(3): e14304, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38368615

RESUMO

BACKGROUND: Artifacts from implantable cardioverter defibrillators (ICDs) are a challenge to magnetic resonance imaging (MRI)-guided radiotherapy (MRgRT). PURPOSE: This study tested an unsupervised generative adversarial network to mitigate ICD artifacts in balanced steady-state free precession (bSSFP) cine MRIs and improve image quality and tracking performance for MRgRT. METHODS: Fourteen healthy volunteers (Group A) were scanned on a 0.35 T MRI-Linac with and without an MR conditional ICD taped to their left pectoral to simulate an implanted ICD. bSSFP MRI data from 12 of the volunteers were used to train a CycleGAN model to reduce ICD artifacts. The data from the remaining two volunteers were used for testing. In addition, the dataset was reorganized three times using a Leave-One-Out scheme. Tracking metrics [Dice similarity coefficient (DSC), target registration error (TRE), and 95 percentile Hausdorff distance (95% HD)] were evaluated for whole-heart contours. Image quality metrics [normalized root mean square error (nRMSE), peak signal-to-noise ratio (PSNR), and multiscale structural similarity (MS-SSIM) scores] were evaluated. The technique was also tested qualitatively on three additional ICD datasets (Group B) including a patient with an implanted ICD. RESULTS: For the whole-heart contour with CycleGAN reconstruction: 1) Mean DSC rose from 0.910 to 0.935; 2) Mean TRE dropped from 4.488 to 2.877 mm; and 3) Mean 95% HD dropped from 10.236 to 7.700 mm. For the whole-body slice with CycleGAN reconstruction: 1) Mean nRMSE dropped from 0.644 to 0.420; 2) Mean MS-SSIM rose from 0.779 to 0.819; and 3) Mean PSNR rose from 18.744 to 22.368. The three Group B datasets evaluated qualitatively displayed a reduction in ICD artifacts in the heart. CONCLUSION: CycleGAN-generated reconstructions significantly improved both tracking and image quality metrics when used to mitigate artifacts from ICDs.


Assuntos
Aprendizado Profundo , Desfibriladores Implantáveis , Radioterapia Guiada por Imagem , Humanos , Artefatos , Imageamento por Ressonância Magnética/métodos , Processamento de Imagem Assistida por Computador/métodos
13.
J Acquir Immune Defic Syndr ; 96(1): 85-91, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38372621

RESUMO

BACKGROUND: Dolutegravir exposure is reduced after switching from efavirenz, which could select for dolutegravir resistance if switching occurs during virologic failure. METHODS: We measured serial dolutegravir trough concentrations after switching from efavirenz in a clinical trial, which randomized some participants to a supplemental dolutegravir dose or placebo for the first 14 days. Changes in dolutegravir trough concentrations between days 3, 7, 14, and 28 were evaluated. The primary outcome was the geometric mean ratio of dolutegravir trough concentrations on day 7 versus day 28. RESULTS: Twenty-four participants received double-dose dolutegravir (50 mg twice daily) and 11 standard dose for the first 14 days. Baseline characteristics were 77% female, median age 36 years, CD4 cell count 254 cells/mm3, and HIV-1 RNA 4.0 log10 copies/mL. The geometric mean ratio (90% CI) of dolutegravir trough concentrations on day 7 versus day 28 was 0.637 (0.485 to 0.837) in the standard-dose group and 1.654 (1.404 to 1.948) in the double-dose group. There was a prolonged induction effect at day 28 in participants with efavirenz slow metaboliser genotypes. One participant in the double-dose group had a dolutegravir trough concentration below the protein-binding adjusted concentration needed to inhibit 90% of HIV-1 (PA-IC90) at day 3. CONCLUSIONS: No participants on standard-dose dolutegravir had dolutegravir trough concentrations below the PA-IC90. Slow efavirenz metaboliser genotypes had higher baseline efavirenz concentrations and more pronounced and longer period of induction postswitch. These findings suggest that a 14-day lead-in supplemental dolutegravir dose may not be necessary when switching from a failing efavirenz-based first-line regimen.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Adulto , Feminino , Humanos , Masculino , Alcinos/farmacocinética , Alcinos/uso terapêutico , Fármacos Anti-HIV/farmacocinética , Fármacos Anti-HIV/uso terapêutico , Benzoxazinas/farmacocinética , Benzoxazinas/uso terapêutico , Ciclopropanos/farmacocinética , Ciclopropanos/uso terapêutico , Compostos Heterocíclicos com 3 Anéis/farmacocinética , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Infecções por HIV/tratamento farmacológico , Oxazinas/farmacocinética , Oxazinas/uso terapêutico , Piperazinas/farmacocinética , Piperazinas/uso terapêutico , Piridonas/farmacocinética , Piridonas/uso terapêutico
14.
Trauma Surg Acute Care Open ; 9(Suppl 1): e001147, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38196929

RESUMO

Objectives: Prehospital transfusion can be life-saving when transport is delayed but conventional plasma, red cells, and whole blood are often unavailable out of hospital. Shelf-stable products are needed as a temporary bridge to in-hospital transfusion. Bioplasma FDP (freeze-dried plasma) and Hemopure (hemoglobin-based oxygen carrier; HBOC) are products with potential for prehospital use. In vivo use of these products together has not been reported. This study assessed the safety of intravenous administration of HBOC+FDP, relative to normal saline (NS), in rhesus macaques (RM). Methods: After 30% blood volume removal and 30 minutes in shock, animals were resuscitated with either NS or two units (RM size adjusted) each of HBOC+FDP during 60 minutes. Sequential blood samples were collected. After neurological assessment, animals were killed at 24 hours and tissues collected for histopathology. Results: Due to a shortage of RM during the COVID-19 pandemic, the study was stopped after nine animals (HBOC+FDP, seven; NS, two). All animals displayed physiologic and tissue changes consistent with hemorrhagic shock and recovered normally. There was no pattern of cardiovascular, blood gas, metabolic, coagulation, histologic, or neurological changes suggestive of risk associated with HBOC+FDP. Conclusion: There was no evidence of harm associated with the combined use of Hemopure and Bioplasma FDP. No differences were noted between groups in safety-related cardiovascular, pulmonary, renal or other organ or metabolic parameters. Hemostasis and thrombosis-related parameters were consistent with expected responses to hemorrhagic shock and did not differ between groups. All animals survived normally with intact neurological function. Level of evidence: Not applicable.

15.
Phys Eng Sci Med ; 47(2): 769-777, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38198064

RESUMO

MRI-guided radiotherapy systems enable beam gating by tracking the target on planar, two-dimensional cine images acquired during treatment. This study aims to evaluate how deep-learning (DL) models for target tracking that are trained on data from one fraction can be translated to subsequent fractions. Cine images were acquired for six patients treated on an MRI-guided radiotherapy platform (MRIdian, Viewray Inc.) with an onboard 0.35 T MRI scanner. Three DL models (U-net, attention U-net and nested U-net) for target tracking were trained using two training strategies: (1) uniform training using data obtained only from the first fraction with testing performed on data from subsequent fractions and (2) adaptive training in which training was updated each fraction by adding 20 samples from the current fraction with testing performed on the remaining images from that fraction. Tracking performance was compared between algorithms, models and training strategies by evaluating the Dice similarity coefficient (DSC) and 95% Hausdorff Distance (HD95) between automatically generated and manually specified contours. The mean DSC for all six patients in comparing manual contours and contours generated by the onboard algorithm (OBT) were 0.68 ± 0.16. Compared to OBT, the DSC values improved 17.0 - 19.3% for the three DL models with uniform training, and 24.7 - 25.7% for the models based on adaptive training. The HD95 values improved 50.6 - 54.5% for the models based on adaptive training. DL-based techniques achieved better tracking performance than the onboard, registration-based tracking approach. DL-based tracking performance improved when implementing an adaptive strategy that augments training data fraction-by-fraction.


Assuntos
Aprendizado Profundo , Pulmão , Imagem Cinética por Ressonância Magnética , Radioterapia Guiada por Imagem , Humanos , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/diagnóstico por imagem , Algoritmos , Processamento de Imagem Assistida por Computador
16.
Tech Coloproctol ; 28(1): 23, 2024 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-38198036

RESUMO

In France, about 2000 new cases of anal cancer are diagnosed annually. Squamous cell carcinoma is the most common histological type, mostly occurring secondary to persistent HPV16 infection. Invasive cancer is preceded by precancerous lesions. In addition to patients with a personal history of precancerous lesions and anal cancer, three groups are at very high risk of anal cancer: (i) men who have sex with men and are living with HIV, (ii) women with a history of high-grade squamous intraepithelial lesions (HSILs) or vulvar HPV cancer, and (iii) women who received a solid organ transplant more than 10 years ago. The purpose of screening is to detect HSILs so that they can be treated, thereby reducing the risk of progression to cancer. All patients with symptoms should undergo a proctological examination including standard anoscopy. For asymptomatic patients at risk, an initial HPV16 test makes it possible to target patients at risk of HSILs likely to progress to cancer. Anal cytology is a sensitive test for HSIL detection. Its sensitivity is greater than 80% and exceeds that of proctological examination with standard anoscopy. It is indicated in the event of a positive HPV16 test. In the presence of cytological abnormalities and/or lesions and a suspicion of dysplasia on clinical examination, high-resolution anoscopy is indicated. Performance is superior to that of proctological examination with standard anoscopy. However, this technique is not widely available, which limits its use. If high-resolution anoscopy is not possible, screening by a standard proctological examination is an alternative. There is a need to develop high-resolution anoscopy and triage tests and to evaluate screening strategies.


Assuntos
Neoplasias do Ânus , Lesões Pré-Cancerosas , Minorias Sexuais e de Gênero , Masculino , Humanos , Feminino , Papillomavirus Humano , Homossexualidade Masculina , Lesões Pré-Cancerosas/diagnóstico , Neoplasias do Ânus/diagnóstico
17.
Phys Med Biol ; 69(3)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38171002

RESUMO

Objective.The goal of this work was to assess the potential use of non-contact scintillator imaging dosimetry for tracking delivery in total body irradiation (TBI).Approach. Studies were conducted to measure the time-gated light signals caused by radiation exposure to scintillators that were placed on tissue. The purpose was to assess efficacy in conditions common for TBI, such as the large source to surface distance (SSD) commonly used, the reduced dose rate, the inclusion of a plexiglass spoiler, angle of incidence and effects of peripheral patient support structures. Dose validation work was performed on phantoms that mimicked human tissue optical properties and body geometry. For this work, 1.5 cm diameter scintillating disks were developed and affixed to phantoms under various conditions. A time-gated camera synchronized to the linac pulses was used for imaging. Scintillation intensity was quantified in post processing and the values verified with simultaneous thermolumiescent dosimeter (TLD) measurements. Mean scintillation values in each region were compared to TLD measurements to produce dose response curves, and scatter effects from the spoiler and patient bed were quantified.Main results.The dose determined by scintillators placed in TBI conditions agreed with TLD dose determinations to within 2.7%, and did so repeatedly within 1.0% standard deviation variance. A linear fit between scintillator signal and TLD dose was achieved with anR2= 0.996 across several body sites. Scatter from the patient bed resulted in a maximum increase of 19% in dose.Significance.This work suggests that non-contact scintillator imaging dosimetry could be used to verify dose in real time to patients undergoing TBI at the prescribed long SSD and low dose rate. It also has shown that patient transport stretchers can significantly influence surface dose by increasing scatter.


Assuntos
Contagem de Cintilação , Irradiação Corporal Total , Humanos , Contagem de Cintilação/métodos , Radiometria/métodos , Dosagem Radioterapêutica , Imagens de Fantasmas , Imagem Óptica/métodos
18.
J Trauma Acute Care Surg ; 96(2): 256-264, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37858305

RESUMO

BACKGROUND: Hemorrhage control in prolonged field care (PFC) presents unique challenges that drive the need for enhanced point of injury treatment capabilities to maintain patient stability beyond the Golden Hour. To address this, two hemostatic agents, Combat Gauze (CG) and XSTAT, were evaluated in a porcine model of uncontrolled junctional hemorrhage for speed of deployment and hemostatic efficacy over 72 hours. METHODS: The left subclavian artery and subscapular vein were isolated in anesthetized male Yorkshire swine (70-85 kg) and injured via 50% transection, followed by 30 seconds of hemorrhage. Combat Gauze (n = 6) or XSTAT (n = 6) was administered until bleeding stopped and remained within subjects for observation over 72 hours. Physiologic monitoring, hemostatic efficacy, and hematological parameters were measured throughout the protocol. Gross necropsy and histology were performed following humane euthanasia. RESULTS: Both CG and XSTAT maintained hemostasis throughout the full duration of the protocol. There were no significant differences between groups in hemorrhage volume (CG: 1021.0 ± 183.7 mL vs. XSTAT: 968.2 ± 243.3 mL), total blood loss (CG: 20.8 ± 2.7% vs. XSTAT: 20.1 ± 5.1%), or devices used (CG: 3.8 ± 1.2 vs. XSTAT: 5.3 ± 1.4). XSTAT absorbed significantly more blood than CG (CG: 199.5 ± 50.3 mL vs. XSTAT: 327.6 ± 71.4 mL) and was significantly faster to administer (CG: 3.4 ± 1.6 minutes vs. XSTAT: 1.4 ± 0.5 minutes). There were no significant changes in activated clot time, prothrombin time, or international normalized ratio between groups or compared with baseline throughout the 72-hour protocol. Histopathology revealed no evidence of microthromboemboli or disseminated coagulopathies across evaluated tissues in either group. CONCLUSION: Combat Gauze and XSTAT demonstrated equivalent hemostatic ability through 72 hours, with no overt evidence of coagulopathies from prolonged indwelling. In addition, XSTAT offered significantly faster administration and the ability to absorb more blood. Taken together, XSTAT offers logistical and efficiency advantages over CG for immediate control of junctional noncompressible hemorrhage, particularly in a tactical environment. In addition, extension of indicated timelines to 72 hours allows translation to PFC.


Assuntos
Hemostáticos , Suínos , Masculino , Humanos , Animais , Hemostáticos/uso terapêutico , Modelos Animais de Doenças , Hemorragia/terapia , Exsanguinação/terapia , Hemostasia , Técnicas Hemostáticas
19.
J Immigr Minor Health ; 26(2): 421-425, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37882970

RESUMO

The COVID-19 pandemic exacerbated racism experienced by Asian Americans, especially women and older individuals. Little is known about how discriminatory experiences during the pandemic have influenced health behaviors among Asian Americans. Between 10/2021 and 6/2022, we surveyed 193 Asian American women in the San Francisco area. Participants were asked to report types of discrimination they experienced since March 2020. We explored bivariable associations of discrimination and changes in health behaviors and healthcare utilization. Most women were Chinese American (75%) and over 45-years-old (87%). The top three discriminatory experiences reported were being treated with less respect (60%), being treated unfairly at restaurants/stores (49%), and people acting as if they are better (47%). Chinese American women (vs. non-Chinese Asian American women) reported higher frequencies of being threatened/harassed (40% vs. 22%). Women who reported any discriminatory experience (vs. none) were more likely to report less physical exercise (42.7% vs. 26.3%) and canceling/rescheduling medical appointments (65.0% vs. 45.1%). Our findings begin to elucidate Asian American women's experiences of discrimination since the pandemic and provide evidence of the harmful impacts of anti-Asian racism on health behaviors.


Assuntos
COVID-19 , Racismo , Humanos , Feminino , Pessoa de Meia-Idade , Asiático , Pandemias , Comportamentos Relacionados com a Saúde , Exercício Físico
20.
J Thorac Oncol ; 19(2): 285-296, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37797733

RESUMO

INTRODUCTION: Preclinical evaluation of bintrafusp alfa (BA) combined with radiotherapy revealed greater antitumor effects than BA or radiotherapy alone. In a phase 1 study, BA exhibited encouraging clinical activity in patients with stage IIIB or IV NSCLC who had received previous treatment. METHODS: This multicenter, double-blind, controlled phase 2 study (NCT03840902) evaluated the safety and efficacy of BA with concurrent chemoradiotherapy (cCRT) followed by BA (BA group) versus placebo with cCRT followed by durvalumab (durvalumab group) in patients with unresectable stage III NSCLC. The primary end point was progression-free survival according to Response Evaluation Criteria in Solid Tumors version 1.1 as assessed by the investigator. On the basis of the recommendation of an independent data monitoring committee, the study was discontinued before the maturity of overall survival data (secondary end point). RESULTS: A total of 153 patients were randomized to either BA (n = 75) or durvalumab groups (n = 78). The median progression-free survival was 12.8 months versus 14.6 months (stratified hazard ratio = 1.48 [95% confidence interval: 0.69-3.17]), in the BA and durvalumab groups, respectively. Trends for overall response rate (29.3% versus 32.1%) and disease control rate (66.7% versus 70.5%) were similar between the two groups. Any-grade treatment-emergent adverse events occurred in 94.6% versus 96.1% of patients in the BA versus durvalumab groups, respectively. Bleeding events in the BA group were mostly grade 1 (21.6%) or 2 (9.5%). CONCLUSIONS: BA with cCRT followed by BA exhibited no efficacy benefit over placebo with cCRT followed by durvalumab in patients with stage III unresectable NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Anticorpos Monoclonais/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Quimiorradioterapia , Fatores Imunológicos/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Estadiamento de Neoplasias
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA