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1.
Front Pharmacol ; 15: 1416701, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39281282

RESUMO

We have reported that D,L-thiol esters, including D-cysteine ethyl ester (D-CYSee), are effective at overcoming opioid-induced respiratory depression (OIRD) in rats. Our on-going studies reveal that co-injections of D-CYSee with multi-day morphine injections markedly diminish spontaneous withdrawal that usually occurs after cessation of multiple injections of morphine in rats. Chronically administered opioids are known (1) to alter cellular redox status, thus inducing an oxidative state, and (2) for an overall decrease in DNA methylation, therefore resulting in the transcriptional activation of previously silenced long interspersed elements (LINE-1) retrotransposon genes. The first objective of the present study was to determine whether D-CYSee and the one carbon metabolism with the methyl donor, betaine, would maintain redox control and normal DNA methylation levels in human neuroblastoma cell cultures (SH-SY5Y) under overnight challenge with morphine (100 nM). The second objective was to determine whether D-CYSee and/or betaine could diminish the degree of physical dependence to morphine in male Sprague Dawley rats. Our data showed that overnight treatment with morphine reduced cellular GSH levels, induced mitochondrial damage, decreased global DNA methylation, and increased LINE-1 mRNA expression. These adverse effects by morphine, which diminished the reducing capacity and compromised the maintenance of the membrane potential of SH-SY5Y cells, was prevented by concurrent application of D-CYSee (100 µM) or betaine (300 µM). Furthermore, our data demonstrated that co-injections of D-CYSee (250 µmol/kg, IV) and to a lesser extent, betaine (250 µmol/kg, IV), markedly diminished the development of physical dependence induced by multi-day morphine injections (escalating daily doses of 10-30 mg/kg, IV), as assessed by the lesser number of withdrawal phenomena elicited by the injection of the opioid receptor antagonist, naloxone (1.5 mg/kg, IV). These findings provide evidence that D-CYSee and betaine prevent the appearance of redox alterations and epigenetic signatures commonly seen in neural cells involved in opioid physical dependence/addiction, and lessen development of physical dependence to morphine.

2.
Front Pharmacol ; 15: 1444574, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39253377

RESUMO

The ability of morphine to decrease cysteine transport into neurons by inhibition of excitatory amino acid transporter 3 (EAA3) may be a key molecular mechanism underlying the acquisition of physical and psychological dependence to morphine. This study examined whether co-administration of the cell-penetrant antioxidant D-thiol ester, D-cysteine ethyl ester (D-CYSee), with morphine, would diminish the development of physical dependence to morphine in male Sprague Dawley rats. Systemic administration of the opioid receptor antagonist, naloxone (NLX), elicited pronounced withdrawal signs (e.g., wet-dog shakes, jumps, rears, circling) in rats that received a subcutaneous depot of morphine (150 mg/kg, SC) for 36 h and continuous intravenous infusion of vehicle (20 µL/h, IV). The NLX-precipitated withdrawal signs were reduced in rats that received an infusion of D-CYSee, but not D-cysteine, (both at 20.8 µmol/kg/h, IV) for the full 36 h. NLX elicited pronounced withdrawal signs in rats treated for 48 h with morphine (150 mg/kg, SC), plus continuous infusion of vehicle (20 µL/h, IV) that began at the 36 h timepoint of morphine treatment. The NLX-precipitated withdrawal signs were reduced in rats that received a 12 h infusion of D-CYSee, but not D-cysteine, (both at 20.8 µmol/kg/h, IV) that began at the 36 h timepoint of morphine treatment. These findings suggest that D-CYSee may attenuate the development of physical dependence to morphine and reverse established dependence to the opioid in male Sprague Dawley rats. Alternatively, D-CYSee may simply suppress the processes responsible for NLX-precipitated withdrawal. Nonetheless, D-CYSee and analogues may be novel therapeutics for the treatment of opioid use disorders.

3.
Clin Cancer Res ; 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39167623

RESUMO

PURPOSE: Anti-programmed cell death protein 1 (PD-1) therapy is a standard of care in recurrent and/or metastatic head and neck squamous cell carcinoma (RMHNSCC). Vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGFR-TKI) have immunomodulatory properties and improve clinical outcomes in combination with anti-PD-1 therapy. We report the long-term efficacy and safety of pembrolizumab and cabozantinib and include a correlative biomarker analysis. PATIENTS AND METHODS: This open-label, single-arm, multicenter, phase 2 study screened 50 patients with RMHNSCC, of whom 36 received pembrolizumab and cabozantinib. Primary endpoint was overall response rate (ORR), safety, and tolerability. Secondary endpoints included progression free survival (PFS), overall survival (OS), and correlative studies of tissue and blood. We report the long-term PFS, OS, safety, and describe correlative biomarkers. RESULTS: With median follow-up of 22.4 months, median PFS was 12.8 months 2-year PFS of 32.6% (95%CI 18.8-56.3%) and median OS of 27.7 months,2-year OS of 54.7% (95%CI 38.9-76.8%). Median duration of response was 12.6 months, with 2-year rate of 38.5% (95%CI 30.8-81.8%). Long-term TRAEs included manageable hypothyroidism (5.5%) and grade 1 elevated AST and ALT (2.8%). Baseline tumor p-MET expression correlated with ORR (p=0.0055). Higher density of CD8+, CD103+, and CSF1-R+ cells at baseline correlated with improved OS (hazard ratio [HR]=5.27, p=0.030; HR =8.79, p=0.017; HR =6.87, p=0.040, respectively). CONCLUSION: Pembrolizumab and cabozantinib provided prolonged encouraging long-term disease control and survival with a maintained favorable safety profile. The prognostic significance of increased CD8+, CD103+ and CSF1-R+ cell density in TIME deserve further evaluation in similar clinical settings.

4.
J Am Acad Dermatol ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39182687

RESUMO

BACKGROUND: Childhood cancer survivors (CCS) are at increased risk for keratinocyte carcinomas (KC) however, the long-term incidence of single and multiple KC is not well established. OBJECTIVE: Identify risk factors and quantify KC cumulative incidence and multiple-incidence burden in CCS. METHODS: KC were identified among Childhood Cancer Survivor Study participants, a cohort of five-year cancer survivors diagnosed <21 years of age between 1970-1999 in North America. Cumulative incidence was estimated, and multivariable models assessed relative rates of KC associated with survivor and treatment characteristics. RESULTS: Among 25,658 participants, 1,446 developed 5,363 KC (93.5% basal cell carcinoma, 6.7% squamous cell carcinoma; mean age 37.0 years (range 7.3-67.4), mean latency 25.7 years; 95.3% White and 88.4% with radiotherapy [RT]). Mean lesion count was 3.7 with 26.1% experiencing ≥4. RT imparted a 4.5-fold increase in the rate of any KC and 9.4-fold increase in the rate of ≥4 KC. Allogeneic and autologous hematopoietic cell transplant were associated with a 3.4- and 2.3-fold increased rate of KC, respectively. LIMITATIONS: Participant self-reporting of some data including race without skin phototype and past medical history may have impacted analysis. CONCLUSIONS: The burden of KC in CCS remains high, but predictable risk factors should guide screening.

5.
Cancers (Basel) ; 16(15)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39123464

RESUMO

Because proton beam therapy (PBT) can lower the dose of radiation to the heart, lungs, and breast, it is an established radiation modality for patients with Hodgkin lymphoma (HL). Pencil beam scanning (PBS) PBT facilitates the treatment of more extensive targets. This may be especially of value for lymphoma patients who require RT to both mediastinal and axillary targets, defined here as extended target RT (ETRT), given the target distribution and need to minimize the lung, heart, and breast dose. Using the Proton Collaborative Group registry, we identified patients with HL treated with PBT to both their mediastinum and axilla, for which DICOM-RT was available. All patients were treated with PBS. To evaluate the dosimetric impact of PBS, we compared delivered PBS plans with VMAT butterfly photon plans optimized to have the same target volume coverage, when feasible. Between 2016 and 2021, twelve patients (median 26 years) received PBS ETRT (median 30.6 Gy (RBE)). Despite the large superior/inferior (SI, median 22.2 cm) and left/right (LR, median 22.8 cm) extent of the ETRT targets, all patients were treated with one isocenter except for two patients (both with SI and LR > 30 cm). Most commonly, anterior beams, with or without posterior beams, were used. Compared to photons, PBS had greater target coverage, better conformity, and lower dose heterogeneity while achieving lower doses to the lungs and heart, but not to the breast. No acute grade 3+ toxicities were reported, including pneumonitis. Proton ETRT in this small cohort was safely delivered with PBS and was associated with an improved sparing of the heart and lungs compared to VMAT.

7.
Front Pharmacol ; 15: 1405461, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38978984

RESUMO

Our lab is investigating the efficacy profiles of tropine analogs against opioid-induced respiratory depression. The companion manuscript reports that the cell-permeant tropeine, tropine ester (Ibutropin), produces a rapid and sustained reversal of the deleterious actions of fentanyl on breathing, alveolar-arterial (A-a) gradient (i.e., index of alveolar gas exchange), and arterial blood-gas (ABG) chemistry in freely-moving male Sprague Dawley rats, while not compromising fentanyl analgesia. We report here that in contrast to Ibutropin, the injection of the parent molecule, tropine (200 µmol/kg, IV), worsens the adverse actions of fentanyl (75 µg/kg, IV) on ventilatory parameters (e.g., frequency of breathing, tidal volume, minute ventilation, peak inspiratory and expiratory flows, and inspiratory and expiratory drives), A-a gradient, ABG chemistry (e.g., pH, pCO2, pO2, and sO2), and sedation (i.e., the righting reflex), while not affecting fentanyl antinociception (i.e., the tail-flick latency) in freely-moving male Sprague Dawley rats. These data suggest that tropine augments opioid receptor-induced signaling events that mediate the actions of fentanyl on breathing and alveolar gas exchange. The opposite effects of Ibutropin and tropine may result from the ability of Ibutropin to readily enter peripheral and central cells. Of direct relevance is that tropine, resulting from the hydrolysis of Ibutropin, would combat the Ibutropin-induced reversal of the adverse effects of fentanyl. Because numerous drug classes, such as cocaine, atropine, and neuromuscular blocking drugs contain a tropine moiety, it is possible that their hydrolysis to tropine has unexpected/unintended consequences. Indeed, others have found that tropine exerts the same behavioral profile as cocaine upon central administration. Together, these data add valuable information about the pharmacological properties of tropine.

9.
Am J Clin Oncol ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38898571

RESUMO

OBJECTIVES: The adoption of transoral robotic surgery and shifting epidemiology in oropharyngeal squamous cell cancer have stimulated debate over upfront and adjuvant treatment. Institutional variation in practice patterns can be obscured in patient-level analyses. We aimed to characterize institutional patterns of care as well as identify potential associations between patterns of care and survival. METHODS: This was a retrospective cohort study of patients identified from 2004-2015 in the National Cancer Database. We analyzed 42,803 cases of oropharyngeal squamous cell cancer Stage cT1-2N0-2bM0 (AJCC 7th edition) treated with curative intent surgery and/or radiotherapy. We defined facility-4-year periods to account for changing institutional practice patterns. The 42,803 patients were treated within 2578 facility-4-year periods. We assessed institutional practice patterns, including the ratio of upfront surgery to definitive radiotherapy, case volumes, use of adjuvant therapies (radiotherapy or chemoradiotherapy), and margin positivity rates. Survival associations with institutional practice patterns were estimated with Cox regression. RESULTS: The ratio of upfront surgery to definitive radiotherapy ranged from 80-to-1 to 1-to-23. The institution-level median rate of adjuvant radiotherapy was 69% (IQR 50%-100%), adjuvant chemoradiotherapy was 44% (IQR 0%-67%), and margin-positive resection was 33% (IQR 0%-50%). On patient-level MVA, worse overall survival was not significantly associated with institutional case volume, adjuvant radiotherapy, or adjuvant chemoradiotherapy utilization. CONCLUSIONS: High rates of multimodal therapy and positive margins underscore the importance of multidisciplinary care and highlight variable patterns of care across institutions. Further work is warranted to explore indicators of high-quality care and to optimize adjuvant therapy in the HPV era.

10.
Lancet Oncol ; 25(7): e318-e330, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38936390

RESUMO

Robust time-to-event endpoint definitions are crucial for the assessment of treatment effect and the clinical value of trial interventions. Here, the Head and Neck Cancer International Group investigated endpoint use in phase 3 trials and trials considered potentially practice-changing published between 2008 and 2021 in the curative-intent setting for patients with mucosal head and neck squamous cell carcinoma. Of the 92 trials reviewed, we show that all core components of endpoint reporting were heterogeneous, including definitions of common terms, such as overall survival and progression-free survival. Our report highlights the urgent need for harmonisation of fundamental components of clinical trial endpoints and the engagement of all stakeholders to ensure the transparent reporting of endpoint details.


Assuntos
Consenso , Determinação de Ponto Final , Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/terapia , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/mortalidade , Determinação de Ponto Final/normas , Ensaios Clínicos Fase III como Assunto , Intervalo Livre de Progressão
11.
Lancet Oncol ; 25(7): e308-e317, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38936389

RESUMO

Transparent and precise endpoint definitions are a crucial aspect of clinical trial conduct and reporting, and are used to communicate the benefit of an intervention. Previous studies have identified inconsistencies in endpoint definitions across oncological clinical trials. Here, the Head and Neck Cancer International Group assessed endpoint definitions from phase 3 trials or trials considered practice-changing for patients with recurrent or metastatic mucosal head and neck squamous cell carcinoma, published between 2008 and 2021. We identify considerable and global heterogeneity in endpoint definitions, which undermines the interpretation of results and development of future studies. We show how fundamental components of even incontrovertible endpoints such as overall survival vary widely, highlighting an urgent need for increased rigour in reporting and harmonisation of endpoints.


Assuntos
Consenso , Determinação de Ponto Final , Neoplasias de Cabeça e Pescoço , Recidiva Local de Neoplasia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Carcinoma de Células Escamosas de Cabeça e Pescoço/secundário , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Recidiva Local de Neoplasia/patologia , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/terapia , Determinação de Ponto Final/normas , Ensaios Clínicos Fase III como Assunto , Metástase Neoplásica
12.
Head Neck ; 46(9): 2167-2177, 2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-38695445

RESUMO

BACKGROUND: The purpose of this study was to provide further insights into whether age and/or sex are associated with prognosis in oral tongue squamous cell carcinoma. METHODS: This was a retrospective cohort study utilizing hospital registry data from 2006 to 2016 obtained from the National Cancer Database. Identified patients were divided into various cohorts based on age, sex, and staging. A descriptive analysis was performed using chi-square tests and overall survival rates were estimated using Kaplan-Meier method. RESULTS: A total of 17 642 patients were included in the study. The 5-year overall survival rates were 82.0% (95% CI: 79.8%-84.0%) in younger patients versus 67.5% (95% CI: 66.7%-68.3%, p-value <0.0001) older patients. The median overall survival for females was 143.4 months (95% CI: 133.2-NA) versus 129.8 (95% CI: 125.4-138.7, p-value <0.0001) in males. CONCLUSIONS: Our analysis suggests that younger age and female sex are both predictors of improved survival in oral tongue squamous cell carcinoma.


Assuntos
Carcinoma de Células Escamosas , Estadiamento de Neoplasias , Neoplasias da Língua , Humanos , Masculino , Feminino , Neoplasias da Língua/mortalidade , Neoplasias da Língua/patologia , Neoplasias da Língua/terapia , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Fatores Etários , Fatores Sexuais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Adulto , Taxa de Sobrevida , Prognóstico , Estudos de Coortes , Idoso de 80 Anos ou mais , Estimativa de Kaplan-Meier , Sistema de Registros , Estados Unidos/epidemiologia
13.
JAMA Oncol ; 10(7): 896-904, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38780927

RESUMO

Importance: Intensity-modulated radiation therapy (IMRT) reirradiation of nonmetastatic recurrent or second primary head and neck squamous cell carcinoma (HNSCC) results in poor progression-free survival (PFS) and overall survival (OS). Objective: To investigate the tolerability, PFS, OS, and patient-reported outcomes with nivolumab (approved standard of care for patients with HNSCC) during and after IMRT reirradiation. Design, Setting, and Participants: In this multicenter nonrandomized phase 2 single-arm trial, the treatment outcomes of patients with recurrent or second primary HNSCC who satisfied recursive partitioning analysis class 1 and 2 definitions were evaluated. Between July 11, 2018, and August 12, 2021, 62 patients were consented and screened. Data were evaluated between June and December 2023. Intervention: Sixty- to 66-Gy IMRT in 30 to 33 daily fractions over 6 to 6.5 weeks with nivolumab, 240 mg, intravenously 2 weeks prior and every 2 weeks for 5 cycles during IMRT, then nivolumab, 480 mg, intravenously every 4 weeks for a total nivolumab duration of 52 weeks. Main Outcomes and Measures: The primary end point was PFS. Secondary end points included OS, incidence, and types of toxic effects, including long-term treatment-related toxic effects, patient-reported outcomes, and correlatives of tissue and blood biomarkers. Results: A total of 62 patients were screened, and 51 were evaluable (median [range] age was 62 [56-67] years; 42 [82%] were male; 6 [12%] had p16+ disease; 38 [75%] had salvage surgery; and 36 [71%.] had neck dissection). With a median follow-up of 24.5 months (95% CI, 19.0-25.0), the estimated 1-year PFS was 61.7% (95% CI, 49.2%-77.4%), rejecting the null hypothesis of 1-year PFS rate of less than 43.8% with 1-arm log-rank test P = .002 within a 1-year timeframe. The most common treatment-related grade 3 or higher adverse event (6 [12%]) was lymphopenia with 2 patients (4%) and 1 patient each (2%) exhibiting colitis, diarrhea, myositis, nausea, mucositis, and myasthenia gravis. Functional Assessment of Cancer Therapy-General and Functional Assessment of Cancer Therapy-Head and Neck Questionnaire quality of life scores remained stable and consistent across all time points. A hypothesis-generating trend favoring worsening PFS and OS in patients with an increase in blood PD1+, KI67+, and CD4+ T cells was observed. Conclusions and Relevance: This multicenter nonrandomized phase 2 trial of IMRT reirradiation therapy and nivolumab suggested a promising improvement in PFS over historical controls. The treatment was well tolerated and deserves further evaluation. Trial Registration: ClinicalTrials.gov Identifier: NCT03521570.


Assuntos
Neoplasias de Cabeça e Pescoço , Recidiva Local de Neoplasia , Nivolumabe , Radioterapia de Intensidade Modulada , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Nivolumabe/uso terapêutico , Nivolumabe/efeitos adversos , Masculino , Feminino , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Radioterapia de Intensidade Modulada/métodos , Radioterapia de Intensidade Modulada/efeitos adversos , Pessoa de Meia-Idade , Idoso , Recidiva Local de Neoplasia/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/terapia , Neoplasias de Cabeça e Pescoço/mortalidade , Reirradiação/métodos , Reirradiação/efeitos adversos , Antineoplásicos Imunológicos/uso terapêutico , Antineoplásicos Imunológicos/efeitos adversos , Segunda Neoplasia Primária , Intervalo Livre de Progressão , Adulto
14.
Front Pharmacol ; 15: 1381073, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38698814

RESUMO

Fentanyl elicits profound disturbances in ventilatory control processes in humans and experimental animals. The traditional viewpoint with respect to fentanyl-induced respiratory depression is that once the effects on the frequency of breathing (Freq), tidal volume (TV), and minute ventilation (MV = Freq × TV) are resolved, then depression of breathing is no longer a concern. The results of the present study challenge this concept with findings, as they reveal that while the apparent inhibitory effects of fentanyl (75 µg/kg, IV) on Freq, TV, and MV in adult male rats were fully resolved within 15 min, many other fentanyl-induced responses were in full effect, including opposing effects on respiratory timing parameters. For example, although the effects on Freq were resolved at 15 min, inspiratory duration (Ti) and end inspiratory pause (EIP) were elevated, whereas expiratory duration (Te) and end expiratory pause (EEP) were diminished. Since the effects of fentanyl on TV had subsided fully at 15 min, it would be expected that the administration of an opioid receptor (OR) antagonist would have minimal effects if the effects of fentanyl on this and other parameters had resolved. We now report that the intravenous injection of a 1.0 mg/kg dose of the peripherally restricted OR antagonist, methyl-naloxone (naloxone methiodide, NLXmi), did not elicit arousal but elicited some relatively minor changes in Freq, TV, MV, Te, and EEP but pronounced changes in Ti and EIP. In contrast, the injection of a 2.5 mg/kg dose of NLXmi elicited pronounced arousal and dramatic changes in many variables, including Freq, TV, and MV, which were not associated with increases in non-apneic breathing events such as apneas. The two compelling conclusions from this study are as follows: 1) the blockade of central ORs produced by the 2.5 mg/kg dose of NLXmi elicits pronounced increases in Freq, TV, and MV in rats in which the effects of fentanyl had apparently resolved, and 2) it is apparent that fentanyl had induced the activation of two systems with counter-balancing effects on Freq and TV: one being an opioid receptor inhibitory system and the other being a non-OR excitatory system.

15.
Sci Rep ; 14(1): 9091, 2024 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643270

RESUMO

N-acetyl-L-cysteine (L-NAC) is a proposed therapeutic for opioid use disorder. This study determined whether co-injections of L-NAC (500 µmol/kg, IV) or its highly cell-penetrant analogue, L-NAC methyl ester (L-NACme, 500 µmol/kg, IV), prevent acquisition of acute physical dependence induced by twice-daily injections of fentanyl (125 µg/kg, IV), and overcome acquired dependence to these injections in freely-moving male Sprague Dawley rats. The injection of the opioid receptor antagonist, naloxone HCl (NLX; 1.5 mg/kg, IV), elicited a series of withdrawal phenomena (i.e. behavioral and cardiorespiratory responses, hypothermia and body weight loss) in rats that received 5 or 10 injections of fentanyl and similar numbers of vehicle co-injections. With respect to the development of dependence, the NLX-precipitated withdrawal phenomena were reduced in rats that received had co-injections of L-NAC, and more greatly reduced in rats that received co-injections of L-NACme. In regard to overcoming established dependence, the NLX-precipitated withdrawal phenomena in rats that had received 10 injections of fentanyl (125 µg/kg, IV) were reduced in rats that had received co-injections of L-NAC, and more greatly reduced in rats that received co-injections of L-NACme beginning with injection 6 of fentanyl. This study provides compelling evidence that co-injections of L-NAC and L-NACme prevent the acquisition of physical dependence and overcome acquired dependence to fentanyl in male rats. The higher efficacy of L-NACme is likely due to its greater cell penetrability in brain regions mediating dependence to fentanyl and interaction with intracellular signaling cascades, including redox-dependent processes, responsible for the acquisition of physical dependence to fentanyl.


Assuntos
Acetilcisteína/análogos & derivados , Lisina/análogos & derivados , Dependência de Morfina , Síndrome de Abstinência a Substâncias , Ratos , Masculino , Animais , Fentanila/farmacologia , Ratos Sprague-Dawley , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia
16.
Antioxidants (Basel) ; 13(4)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38671945

RESUMO

The present study examined the hypothesis that changes in the oxidation-reduction state of thiol residues in functional proteins play a major role in the expression of the ventilatory responses in conscious rats that occur during a hypoxic-hypercapnic (HH) gas challenge and upon return to room air. A HH gas challenge in vehicle-treated rats elicited robust and sustained increases in minute volume (via increases in frequency of breathing and tidal volume), peak inspiratory and expiratory flows, and inspiratory and expiratory drives while minimally affecting the non-eupneic breathing index (NEBI). The HH-induced increases in these parameters, except for frequency of breathing, were substantially diminished in rats pre-treated with the potent and lipophilic disulfide-reducing agent, L,D-dithiothreitol (100 µmol/kg, IV). The ventilatory responses that occurred upon return to room air were also substantially different in dithiothreitol-treated rats. In contrast, pre-treatment with a substantially higher dose (500 µmol/kg, IV) of the lipophilic congener of the monosulfide, N-acetyl-L-cysteine methyl ester (L-NACme), only minimally affected the expression of the above-mentioned ventilatory responses that occurred during the HH gas challenge or upon return to room air. The effectiveness of dithiothreitol suggests that the oxidation of thiol residues occurs during exposure to a HH gas challenge and that this process plays an essential role in allowing for the expression of the post-HH excitatory phase in breathing. However, this interpretation is contradicted by the lack of effects of L-NACme. This apparent conundrum may be explained by the disulfide structure affording unique functional properties to dithiothreitol in comparison to monosulfides. More specifically, the disulfide structure may give dithiothreitol the ability to alter the conformational state of functional proteins while transferring electrons. It is also possible that dithiothreitol is simply a more efficient reducing agent following systemic injection, although one interpretation of the data is that the effects of dithiothreitol are not due to its reducing ability.

17.
Adv Radiat Oncol ; 9(3): 101395, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38304108

RESUMO

Purpose: The effect of climate-driven events, such as wildfires, on health care delivery and cancer care is a growing concern. Patients with cancer undergoing radiation therapy are particularly vulnerable to treatment interruptions, which have a direct effect on survival. We report the results of a study characterizing the effect of wildfires on radiation oncology clinics and their patients. Methods and Materials: A survey of California radiation oncologists was used to evaluate emergency preparedness and the effect of wildfires on the delivery of radiation therapy services between 2017 and 2022. Descriptive statistics and Pearson's χ2 tests were performed to investigate potential relationships between provider characteristics, practice settings, and perceptions of the effect of wildfire events. California Department of Forestry and Fire Protection data were employed to map the geographic distribution of wildfires to clinic locations. Results: Response rate was 12.3% (51/415 radiation oncologists), representing 25% of clinics (43/176) in 41% (24/58) of California counties. Sixty-one percent (31/51) of respondents reported being affected by a wildfire, 2 of which are rural clinics (100%, 2/2) and 29 are (59%, 29/49) metropolitan practices. Of these, 18% (9/51) reported a clinic closure, and 29% (15/51) reported staffing shortages. Respondents reported effects on patients, including having to evacuate (55%, 28/51), cancel/reschedule treatments (53%, 27/51), and experiencing physical, mental, or financial hardship due to wildfires (45%, 23/51). Respondents described effects on clinical operations, including being forced to transfer patients (24%, 12/51), transportation interruptions (37%, 19/51), regional/community evacuations (35%, 18/51), and physical/mental health effects (27%, 14/51) on clinic personnel. Less than half of the respondents (47%, 24/51) reported their workplace had a wildfire emergency preparedness plan. Additionally, geographic analysis revealed that 100% (176/176) of clinics were located within 25 miles of a wildfire. Conclusions: This study highlights the effects of wildfires on radiation oncology clinics and patients and underscores the need for emergency preparedness planning to minimize the consequences of such disasters.

18.
Biomed Pharmacother ; 171: 116081, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38219385

RESUMO

L-cysteine ethylester (L-CYSee) is a membrane-permeable analogue of L-cysteine with a variety of pharmacological effects. The purpose of this study was to determine the effects of L-CYSee on morphine-induced changes in ventilation, arterial-blood gas (ABG) chemistry, Alveolar-arterial (A-a) gradient (i.e., a measure of the index of alveolar gas-exchange), antinociception and sedation in male Sprague Dawley rats. An injection of morphine (10 mg/kg, IV) produced adverse effects on breathing, including sustained decreases in minute ventilation. L-CYSee (500 µmol/kg, IV) given 15 min later immediately reversed the actions of morphine. Another injection of L-CYSee (500 µmol/kg, IV) after 15 min elicited more pronounced excitatory ventilatory responses. L-CYSee (250 or 500 µmol/kg, IV) elicited a rapid and prolonged reversal of the actions of morphine (10 mg/kg, IV) on ABG chemistry (pH, pCO2, pO2, sO2) and A-a gradient. L-serine ethylester (an oxygen atom replaces the sulfur; 500 µmol/kg, IV), was ineffective in all studies. L-CYSee (500 µmol/kg, IV) did not alter morphine (10 mg/kg, IV)-induced sedation, but slightly reduced the overall duration of morphine (5 or 10 mg/kg, IV)-induced analgesia. In summary, L-CYSee rapidly overcame the effects of morphine on breathing and alveolar gas-exchange, while not affecting morphine sedation or early-stage analgesia. The mechanisms by which L-CYSee modulates morphine depression of breathing are unknown, but appear to require thiol-dependent processes.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Morfina , Ratos , Masculino , Animais , Morfina/farmacologia , Cisteína/farmacologia , Ratos Sprague-Dawley , Respiração , Gasometria , Dor
19.
Pract Radiat Oncol ; 14(1): e1-e8, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37802397

RESUMO

PURPOSE: Early exposure to oncology care during the preclinical years of medical school may translate to increased student interest in oncology-related fields and improved understanding of oncologic treatment modalities, including radiation oncology. Many schools incorporate problem-based learning (PBL) into the medical school curriculum; this is an opportunity to immerse students in oncologic case management. We describe the effective incorporation of one course into the medical school curriculum that may be replicated at other institutions. METHODS AND MATERIALS: A PBL case regarding pancreatic cancer was created by a radiation oncology resident and faculty member in collaboration with the gastrointestinal course director for first-year medical students at a single institution. Pancreatic cancer was chosen based on curricular needs. Learning objectives were discussed to guide the creation of the case. RESULTS: All 140 first-year medical students participated in the 1-hour small group case focused on oncologic work up, multidisciplinary care, and radiation therapy concepts. Students were provided with a case prompt and resources to review prior to the PBL session. Volunteer radiation oncology facilitators attended a 30-minute educational meeting and were provided a detailed case guide 1 week before the PBL session. During the PBL case, facilitators guided students to achieve desired learning objectives. Among the 76 (54%) medical students who completed an optional post-PBL survey, the majority reported that the case motivated them to learn more about oncology (89%) and radiation oncology (82%). There was an increase in the number of subscribers to the Oncology Interest Group (43% increase from previous year) and preclinical students shadowing in the radiation oncology department. The PBL case was continued in future years for all first-year students and extended to 2 hours to promote additional discussion in response to student and facilitator feedback. CONCLUSIONS: A cancer-specific PBL case facilitated by radiation oncology educators is an effective avenue to integrate radiation oncology into the preclinical curriculum and stimulate interest in oncology among first-year medical students.


Assuntos
Neoplasias Pancreáticas , Radioterapia (Especialidade) , Estudantes de Medicina , Humanos , Aprendizagem Baseada em Problemas/métodos , Currículo
20.
Am J Clin Oncol ; 47(5): 210-216, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38149838

RESUMO

BACKGROUND: This practice parameter was revised collaboratively by the American College of Radiology (ACR), and the American Radium Society (ARS). Timely, accurate, and effective communications are critical to quality and safety in contemporary medical practices. Radiation oncology incorporates the science and technology of complex, integrated treatment delivery and the art of providing care to individual patients. Through written physical and/or electronic reports and direct communication, radiation oncologists convey their knowledge and evaluation regarding patient care, clinical workup, and treatment provided to others in the management of the patient. Applicable practice parameters need to be revised periodically regarding medical record documentation for professional and technical components of services delivered. METHODS: This practice parameter was developed and revised according to the process described under the heading "The Process for Developing ACR Practice Parameters and Technical Standards" on the ACR website ( https://www.acr.org/Clinical-Resources/Practice-Parameters-and-Technical-Standards ) by the Committee on Practice Parameters-Radiation Oncology of the ACR Commission on Radiation Oncology in collaboration with the ARS. Both societies have reviewed and approved the document. RESULTS: This practice parameter addresses radiation oncology communications in general, including (a) medical record, (b) electronic, and (c) doctor-patient communications, as well as specific documentation for radiation oncology reports such as (a) consultation, (b) clinical treatment management notes (including inpatient communication), (c) treatment (completion) summary, and (d) follow-up visits. CONCLUSIONS: The radiation oncologist's participation in the multidisciplinary management of patients is reflected in timely, medically appropriate, and informative communication with patients, caregivers, referring physician, and other members of the health care team. The ACR-ARS Practice Parameter for Communication: Radiation Oncology is an educational tool designed to assist practitioners in providing appropriate communication regarding radiation oncology care for patients.


Assuntos
Comunicação , Radioterapia (Especialidade) , Humanos , Radioterapia (Especialidade)/normas , Relações Médico-Paciente , Sociedades Médicas , Estados Unidos
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