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1.
Ann Surg ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38841851

RESUMO

OBJECTIVE: To investigate how the Siewert classification of gastroesophageal junction adenocarcinomas correlates with genomic profiles. SUMMARY/BACKGROUND DATA: Current staging and treatment guidelines recommend that tumors with an epicenter less than 2 cm into the gastric cardia be treated as esophageal cancers, while tumors with epicenter greater than 2 cm into the cardia be staged and treated as gastric cancers. To date, however, few studies have compared the genomic profiles of the 3 Siewert classification groups to validate this distinction. METHODS: Using targeted tumor sequencing data on patients with adenocarcinoma of the gastroesophageal junction previously treated with surgery at our institution, we compared genomic features across Siewert classification groups. RESULTS: A total of 350 patients were included: 121 had Siewert type I, 170 type II, and 59 type III. Comparisons by Siewert location revealed that Siewert type I and II were primarily characterized as the chromosomal instability (CIN) molecular subtype and displayed Barrett's metaplasia and p53 and cell cycle pathway dysregulation. Siewert type III tumors, by contrast, were more heterogeneous, including higher proportions of microsatellite instability (MSI) and genomically stable (GS) tumors and more frequently displayed ARID1A and somatic CDH1 alterations, signet ring cell features, and poor differentiation. Overall, Siewert type I and II tumors demonstrated greater genomic overlap with lower esophageal tumors, while Siewert type III tumors shared genomic features with gastric tumors. CONCLUSIONS: Overall, our results support recent updates in treatment and staging guidelines. Ultimately, however, molecular rather than anatomic classification may prove more valuable in determining staging, treatment, and prognosis.

2.
Can Commun Dis Rep ; 50(5): 153-157, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38835504

RESUMO

Trichinellosis is a parasitic zoonotic disease transmitted through the consumption of meat from animals infected with Trichinella spp. nematodes. In North America, human trichinellosis is rare and is most commonly acquired through consumption of wild game meat. In July 2022, a hospitalized patient with suspected trichinellosis was reported to the Minnesota Department of Health. One week before symptom onset, the patient and eight other persons shared a meal that included bear meat that had been frozen for 45 days before being grilled and served rare with vegetables that had been cooked with the meat. Investigation identified six trichinellosis cases, including two in persons who consumed only the vegetables. Motile Trichinella larvae were found in remaining bear meat that had been frozen for >15 weeks. Molecular testing identified larvae from the bear meat as Trichinella nativa, a freeze-resistant species. Persons who consume meat from wild game animals should be aware that that adequate cooking is the only reliable way to kill Trichinella parasites and that infected meat can cross-contaminate other foods.

3.
Chest ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38885896

RESUMO

A universal nomenclature of the anatomic extent of lung cancer has been critical for individual patient care as well as research advances. As progress occurs, new details emerge that need to be included in a refined system that aligns with contemporary clinical management issues. The 9th edition TNM classification of lung cancer, which is scheduled to take effect in January of 2025, addresses this need. It is based on a large international database, multidisciplinary input and extensive statistical analyses. Key features of the 9th edition include validation of the significant changes in the T component introduced in the 8th edition, subdivision of N2 after exploration of fundamentally different ways of categorizing the N component, and further subdivision of the M component. This has led to reordering of the TNM combinations included in stage groups, primarily involving stage groups IIA, IIB, IIIA and IIIB. This paper summarizes the analyses and revisions for the TNM classification of lung cancer to familiarize the broader medical community and facilitate implementation of the 9th edition system.

4.
Chem Sci ; 15(22): 8414-8421, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38846390

RESUMO

Insoluble amyloids rich in cross-ß fibrils are observed in a number of neurodegenerative diseases. Depending on the clinicopathology, the amyloids can adopt distinct supramolecular assemblies, termed conformational strains. However, rapid methods to study amyloids in a conformationally specific manner are lacking. We introduce a novel computational method for de novo design of peptides that tile the surface of α-synuclein fibrils in a conformationally specific manner. Our method begins by identifying surfaces that are unique to the conformational strain of interest, which becomes a "target backbone" for the design of a peptide binder. Next, we interrogate structures in the PDB with high geometric complementarity to the target. Then, we identify secondary structural motifs that interact with this target backbone in a favorable, highly occurring geometry. This method produces monomeric helical motifs with a favorable geometry for interaction with the strands of the underlying amyloid. Each motif is then symmetrically replicated to form a monolayer that tiles the amyloid surface. Finally, amino acid sequences of the peptide binders are computed to provide a sequence with high geometric and physicochemical complementarity to the target amyloid. This method was applied to a conformational strain of α-synuclein fibrils, resulting in a peptide with high specificity for the target relative to other amyloids formed by α-synuclein, tau, or Aß40. This designed peptide also markedly slowed the formation of α-synuclein amyloids. Overall, this method offers a new tool for examining conformational strains of amyloid proteins.

5.
6.
Ann Intern Med ; 177(5): JC51, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38710079

RESUMO

SOURCE CITATION: Giamarellos-Bourboulis EJ, Siampanos A, Bolanou A, et al. Clarithromycin for early anti-inflammatory responses in community-acquired pneumonia in Greece (ACCESS): a randomised, double-blind, placebo-controlled trial. Lancet Respir Med. 2024;12:294-304. 38184008.


Assuntos
Antibacterianos , Claritromicina , Infecções Comunitárias Adquiridas , Humanos , Claritromicina/administração & dosagem , Claritromicina/uso terapêutico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Método Duplo-Cego , Administração Oral , Pneumonia/tratamento farmacológico , Masculino , Feminino , Pneumonia Bacteriana/tratamento farmacológico , Pessoa de Meia-Idade , Quimioterapia Combinada
8.
Adv Radiat Oncol ; 9(6): 101500, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38699671

RESUMO

Purpose: We investigated whether pulmonary metastases from historically considered radioresistant primaries would have inferior local control after radiation therapy than those from nonradioresistant nonlung primaries, and whether higher biologically effective dose assuming alpha/beta=10 (BED10) would be associated with superior local control. Methods and Materials: We identified patients treated with radiation therapy for oligometastatic or oligoprogressive pulmonary disease to 1 to 5 lung metastases from nonlung primaries in 2013 to 2020 at a single health care system. Radioresistant primary cancers included colorectal carcinoma, endometrial carcinoma, renal cell carcinoma, melanoma, and sarcoma. Nonradioresistant primary cancers included breast, bladder, esophageal, pancreas, and head and neck carcinomas. The Kaplan-Meier estimator, log-rank test, and multivariable Cox proportional hazards regression were used to compare local recurrence-free survival (LRFS), new metastasis-free survival, progression-free survival, and overall survival. Results: Among 114 patients, 73 had radioresistant primary cancers. The median total dose was 50 Gy (IQR, 50-54 Gy) and the median number of fractions was 5 (IQR, 3-5). Median follow-up time was 59.6 months. One of 41 (2.4%) patients with a nonradioresistant metastasis experienced local failure compared with 18 of 73 (24.7%) patients with radioresistant metastasis (log-rank P = .004). Among radioresistant metastases, 12 of 41 (29.2%) patients with colorectal carcinoma experienced local failure compared with 6 of 32 (18.8%) with other primaries (log-rank P = .018). BED10 ≥100 Gy was associated with decreased risk of local recurrence. On univariable analysis, BED10 ≥100 Gy (hazard ratio [HR], 0.263; 95% CI, 0.105-0.656; P = .004) was associated with higher LRFS, and colorectal primary (HR, 3.060; 95% CI, 1.204-7.777; P = .019) was associated with lower LRFS, though these were not statistically significant on multivariable analysis. Among colorectal primary patients, BED10 ≥100 Gy was associated with higher LRFS (HR, 0.266; 95% CI, 0.072-0.985; P = .047) on multivariable analysis. Conclusions: Local control after radiation therapy was encouraging for pulmonary metastases from most nonlung primaries, even for many of those classically considered to be radioresistant. Those from colorectal primaries may benefit from testing additional strategies, such as resection or systemic treatment concurrent with radiation.

9.
Anal Chem ; 96(21): 8424-8431, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38749922

RESUMO

The elementary steps of the electrocatalytic reduction of S2O82- using the Ru(NH3)63+/2+ redox couple were investigated using scanning electrochemical microscopy (SECM) and steady-state voltammetry (SSV). SECM investigations were carried out in a 0.1 M KCl solution using a 3.5 µm radius carbon ultramicroelectrode (UME) as the SECM tip and a 25 µm radius platinum UME as the substrate electrode. Approach curves were recorded in the positive feedback mode of SECM by reducing Ru(NH3)63+ at the tip electrode and oxidizing Ru(NH3)62+ at the substrate electrode, as a function of the tip-substrate separation and S2O82- concentration. The one-electron reaction between electrogenerated Ru(NH3)62+ and S2O82- yields the unstable S2O83•-, which rapidly dissociates to produce highly oxidizing SO4•-. Because SO4•- is such a strongly oxidizing species, it can be further reduced at both the tip and the substrate, or it can react with Ru(NH3)62+ to regenerate Ru(NH3)63+. SECM approach curves display a complex dependence on the tip-substrate distance, d, due to redox mediation reactions at both the tip and the substrate. Finite element method (FEM) simulations of both SECM approach curves and SSV confirm a previously proposed mechanism for the mediated reduction of S2O82- using the Ru(NH3)63+/2+ redox couple. Our results provide a lower limit for dissociation rate constant of S2O83•- (∼1 × 106 s-1), as well as the rate constants for electron transfer between SO4•- and Ru(NH3)62+ (∼1 × 109 M-1 s-1) and between S2O82- and Ru(NH3)62+ (∼7 × 105 M-1 s-1).

10.
MMWR Morb Mortal Wkly Rep ; 73(20): 456-459, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38781100

RESUMO

Trichinellosis is a parasitic zoonotic disease transmitted through the consumption of meat from animals infected with Trichinella spp. nematodes. In North America, human trichinellosis is rare and is most commonly acquired through consumption of wild game meat. In July 2022, a hospitalized patient with suspected trichinellosis was reported to the Minnesota Department of Health. One week before symptom onset, the patient and eight other persons shared a meal that included bear meat that had been frozen for 45 days before being grilled and served rare with vegetables that had been cooked with the meat. Investigation identified six trichinellosis cases, including two in persons who consumed only the vegetables. Motile Trichinella larvae were found in remaining bear meat that had been frozen for >15 weeks. Molecular testing identified larvae from the bear meat as Trichinella nativa, a freeze-resistant species. Persons who consume meat from wild game animals should be aware that that adequate cooking is the only reliable way to kill Trichinella parasites and that infected meat can cross-contaminate other foods.


Assuntos
Surtos de Doenças , Carne , Triquinelose , Triquinelose/epidemiologia , Triquinelose/diagnóstico , Humanos , Animais , Masculino , Minnesota/epidemiologia , Feminino , Adulto , South Dakota/epidemiologia , Arizona/epidemiologia , Carne/parasitologia , Pessoa de Meia-Idade , Trichinella/isolamento & purificação , Ursidae/parasitologia , Adolescente , Idoso , Adulto Jovem
11.
Adv Radiat Oncol ; 9(4): 101413, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38778819

RESUMO

Purpose: The landmark randomized trial on chest irradiation in extensive disease small cell lung cancer (CREST) demonstrated that consolidative thoracic radiation therapy (cTRT) improved overall (OS) and progression-free survival (PFS) after initial chemotherapy (chemo) in extensive-stage small cell lung cancer, with potentially increased benefit in women compared with men. It is unknown whether similar findings would apply after chemoimmunotherapy became the standard first-line treatment. In this analysis, we report national practice patterns and survival outcomes of cTRT according to patient sex. Methods and Materials: We included patients from de-identified electronic health record-derived database diagnosed with stage IV small cell lung cancer (2014-2021) who completed 4 to 6 cycles of first-line systemic therapy (platinum-doublet chemotherapy or chemoimmunotherapy). We evaluated OS and PFS using multivariable Cox proportional hazards regression with receipt of cTRT as an independent variable and stratified by sex. As a sensitivity analysis, we weighted the models by the inverse probability of receiving cTRT. Results: A total of 1227 patients were included (850 chemotherapy, 377 chemoimmunotherapy). There were no statistically significant differences in baseline characteristics between patients who did and did not receive cTRT. Among women, cTRT was associated with superior OS (adjusted hazard ratio [HR], 0.67; 95% CI, 0.52-0.87) and PFS (HR, 0.63; 95% CI, 0.49-0.82) compared with those not receiving cTRT. Conversely, no OS or PFS benefit with cTRT was observed in men (OS HR, 1.03; 95% CI, 0.80-1.31; PFS HR, 1.12; 95% CI, 0.85-1.47). Findings were similar in weighted analyses. Conclusions: The survival efficacy of cTRT may be moderated by sex, with female patients appearing more likely to benefit than male patients. These findings reflect sex-based survival trends with similar effect sizes to those observed in the CREST trial. Although the underpinnings of this association need to be elucidated, stratification by sex should be considered for randomized-controlled trials studying cTRT in extensive-stage small cell lung cancer.

12.
Nat Chem ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710831

RESUMO

Neptunium is an actinide element sourced from anthropogenic production, and, unlike naturally abundant uranium, its coordination chemistry is not well developed in all accessible oxidation states. High-valent neptunium generally requires stabilization from at least one metal-ligand multiple bond, and departing from this structural motif poses a considerable challenge. Here we report a tetrahedral molecular neptunium(V) complex ([Np5+(NPC)4][B(ArF5)4], 1-Np) (NPC = [NPtBu(pyrr)2]-; tBu = C(CH3)3; pyrr = pyrrolidinyl (N(C2H4)2); B(ArF5)4 = tetrakis(2,3,4,5,6-pentafluourophenyl)borate). Single-crystal X-ray diffraction, solution-state spectroscopy and density functional theory studies of 1-Np and the product of its proton-coupled electron transfer (PCET) reaction, 2-Np, demonstrate the unique bonding that stabilizes this reactive ion and establishes the thermochemical and kinetic parameters of PCET in a condensed-phase transuranic complex. The isolation of this four-coordinate, neptunium(V) complex reveals a fundamental reaction pathway in transuranic chemistry.

13.
JAMA Oncol ; 10(6): 799-806, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38602670

RESUMO

Importance: The treatment of locally advanced non-small cell lung cancer (LA-NSCLC) has been informed by more than 5 decades of clinical trials and other relevant literature. However, controversies remain regarding the application of various radiation and systemic therapies in commonly encountered clinical scenarios. Objective: To develop case-referenced consensus and evidence-based guidelines to inform clinical practice in unresectable LA-NSCLC. Evidence Review: The American Radium Society (ARS) Appropriate Use Criteria (AUC) Thoracic Committee guideline is an evidence-based consensus document assessing various clinical scenarios associated with LA-NSCLC. A systematic review of the literature with evidence ratings was conducted to inform the appropriateness of treatment recommendations by the ARS AUC Thoracic Committee for the management of unresectable LA-NSCLC. Findings: Treatment appropriateness of a variety of LA-NSCLC scenarios was assessed by a consensus-based modified Delphi approach using a range of 3 points to 9 points to denote consensus agreement. Committee recommendations were vetted by the ARS AUC Executive Committee and a 2-week public comment period before official approval and adoption. Standard of care management of good prognosis LA-NSCLC consists of combined concurrent radical (60-70 Gy) platinum-based chemoradiation followed by consolidation durvalumab immunotherapy (for patients without progression). Planning and delivery of locally advanced lung cancer radiotherapy usually should be performed using intensity-modulated radiotherapy techniques. A variety of palliative and radical fractionation schedules are available to treat patients with poor performance and/or pulmonary status. The salvage therapy for a local recurrence after successful primary management is complex and likely requires both multidisciplinary input and shared decision-making with the patient. Conclusions and Relevance: Evidence-based guidance on the management of various unresectable LA-NSCLC scenarios is provided by the ARS AUC to optimize multidisciplinary patient care for this challenging patient population.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/terapia , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/patologia , Consenso , Sociedades Médicas , Estados Unidos , Quimiorradioterapia/normas
14.
J Invertebr Pathol ; 204: 108110, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38631558

RESUMO

Disease is a major threat to the economic, ecological and cultural services provided by wild bivalve populations. Over the past decade anecdotal reports on declining health of native bivalve populations around Aotearoa New Zealand have been supported by increasing observations of mass die-offs. Causes of declining health and mass die-offs of wild bivalves are not clear and could be due to a number of interactive and cumulative factors, including declining water quality, climate change, or disease. Pipi/kokota (Paphies australis) within the Whangarei area (northern New Zealand) have suffered repeated die-offs and declining health since at least 2009. Baseline health data for wild native bivalve populations are scarce making it difficult to identify changes in pathogen infection prevalence and intensity and infer their importance to host health. This research aimed to examine and document the health of pipi in Whangarei with the objective of identifying factors that may contribute to their ill health and lack of population recovery. We sampled pipi from four sites within Whangarei, eight times across two years (total n = 640) to establish a health baseline using histopathology, general bacteriology, and qPCR for the intracellular bacteria Endozoicomonas spp. Three pipi mass die-offs occurred during the sampling window that were opportunistically sampled to compare against the health baseline established using healthy pipi. An increase in bacterial growth and a decrease in the abundance of Endozoicomonas spp. in mortality pipi was observed compared with the health baseline. Establishing a health baseline for pipi from Whangarei provided a benchmark to assess changes in a pipi population experiencing high mortality. Such data can help identify factors contributing to die-offs and to help inform what mitigation, if any, is possible in wild shellfish populations.


Assuntos
Bivalves , Animais , Nova Zelândia , Bivalves/microbiologia , Bivalves/parasitologia
15.
J Am Chem Soc ; 146(17): 12030-12039, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38648269

RESUMO

The complex nature of the f-orbital electronic structures and their interaction with the chemical environment pose significant computational challenges. Advanced computational techniques that variationally include scalar relativities and spin-orbit coupling directly at the molecular orbital level have been developed to address this complexity. Among these, variational relativistic multiconfigurational multireference methods stand out for their high accuracy and systematic improvement in studies of f-block complexes. Additionally, these advanced methods offer the potential for calibrating low-scaling electronic structure methods such as density functional theory. However, studies on the Cl K-edge X-ray absorption spectra of the [Ce(III)Cl6]3- and [Ce(IV)Cl6]2- complexes show that time-dependent density functional theory with approximate exchange-correlation kernels can lead to inaccuracies, resulting in an overstabilization of 4f orbitals and incorrect assessments of covalency. In contrast, approaches utilizing small active space wave function methods may understate the stability of these orbitals. The results herein demonstrate the need for large active space, multireference, and variational relativistic methods in studying f-block complexes.

16.
J Clin Med ; 13(8)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38673682

RESUMO

Background/Objective: Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by lifelong impacts on functional social and daily living skills, and restricted, repetitive behaviors (RRBs). Applied behavior analysis (ABA), the gold-standard treatment for ASD, has been extensively validated. ABA access is hindered by limited availability of qualified professionals and logistical and financial barriers. Scientifically validated, parent-led ABA can fill the accessibility gap by overcoming treatment barriers. This retrospective cohort study examines how our ABA treatment model, utilizing parent behavior technicians (pBTs) to deliver ABA, impacts adaptive behaviors and interfering behaviors (IBs) in a cohort of children on the autism spectrum with varying ASD severity levels, and with or without clinically significant IBs. Methods: Clinical outcomes of 36 patients ages 3-15 years were assessed using longitudinal changes in Vineland-3 after 3+ months of pBT-delivered ABA treatment. Results: Within the pBT model, our patients demonstrated clinically significant improvements in Vineland-3 Composite, domain, and subdomain scores, and utilization was higher in severe ASD. pBTs utilized more prescribed ABA when children initiated treatment with clinically significant IBs, and these children also showed greater gains in their Composite scores. Study limitations include sample size, inter-rater reliability, potential assessment metric bias and schedule variability, and confounding intrinsic or extrinsic factors. Conclusion: Overall, our pBT model facilitated high treatment utilization and showed robust effectiveness, achieving improved adaptive behaviors and reduced IBs when compared to conventional ABA delivery. The pBT model is a strong contender to fill the widening treatment accessibility gap and represents a powerful tool for addressing systemic problems in ABA treatment delivery.

17.
J Am Chem Soc ; 146(15): 10268-10273, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38564671

RESUMO

High-valent cerium complexes of alkyl and benzyl ligands are unprecedented due to the incompatibility of the typically highly oxidizing Ce4+ ion and the reducing alkyl or benzyl ligand. Herein we report the synthesis and isolation of the first tetravalent cerium alkyl and benzyl complexes supported by the tri-tert-butyl imidophosphorane ligand, [NP(tBu)3]1-. The Ce4+ monoiodide complex, [Ce4+I(NP(tert-butyl)3)3] (1-CeI), serves as a precursor to the alkyl and benzyl complexes, [Ce4+(Npt)(NP(tert-butyl)3)3] (2-CeNpt) (Npt = neopentyl, CH2C(CH3)3) and [Ce4+(Bn)(NP(tert-butyl)3)3] (2-CeBn) (Bn = benzyl, CH2Ph). The bonding and structure of these complexes are characterized by single-crystal XRD, NMR and UV-vis-NIR spectroscopy, cyclic voltammetry, and DFT studies.

18.
Cell Rep ; 43(3): 113815, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38428421

RESUMO

Diabetes-associated atherosclerosis involves excessive immune cell recruitment and plaque formation. However, the mechanisms remain poorly understood. Transcriptomic analysis of the aortic intima in Ldlr-/- mice on a high-fat, high-sucrose-containing (HFSC) diet identifies a macrophage-enriched nuclear long noncoding RNA (lncRNA), MERRICAL (macrophage-enriched lncRNA regulates inflammation, chemotaxis, and atherosclerosis). MERRICAL expression increases by 249% in intimal lesions during progression. lncRNA-mRNA pair genomic mapping reveals that MERRICAL positively correlates with the chemokines Ccl3 and Ccl4. MERRICAL-deficient macrophages exhibit lower Ccl3 and Ccl4 expression, chemotaxis, and inflammatory responses. Mechanistically, MERRICAL guides the WDR5-MLL1 complex to activate CCL3 and CCL4 transcription via H3K4me3 modification. MERRICAL deficiency in HFSC diet-fed Ldlr-/- mice reduces lesion formation by 74% in the aortic sinus and 86% in the descending aorta by inhibiting leukocyte recruitment into the aortic wall and pro-inflammatory responses. These findings unveil a regulatory mechanism whereby a macrophage-enriched lncRNA potently inhibits chemotactic responses, alleviating lesion progression in diabetes.


Assuntos
Doenças da Aorta , Aterosclerose , Diabetes Mellitus , Placa Aterosclerótica , RNA Longo não Codificante , Animais , Camundongos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Quimiotaxia , Doenças da Aorta/genética , Doenças da Aorta/metabolismo , Doenças da Aorta/patologia , Aterosclerose/metabolismo , Macrófagos/metabolismo , Diabetes Mellitus/patologia , Camundongos Knockout , Camundongos Endogâmicos C57BL , Receptores de LDL , Placa Aterosclerótica/metabolismo
19.
J Exp Anal Behav ; 121(3): 314-326, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38499477

RESUMO

Resurgence refers to the relapse of a target behavior following the worsening of a source of alternative reinforcement that was made available during response elimination. Most laboratory analyses of resurgence have used a combination of extinction and alternative reinforcement to reduce target behavior. In contingency-management treatments for alcohol use disorder, however, alcohol use is not placed on extinction. Instead, participants voluntarily abstain from alcohol use to access nondrug alternative reinforcers. Inasmuch, additional laboratory research on resurgence following voluntary abstinence is warranted. The present experiment evaluated resurgence of rats' ethanol seeking following voluntary abstinence produced by differential reinforcement of other behavior (DRO). Lever pressing produced ethanol reinforcers during baseline phases. During DRO phases, lever pressing continued to produce ethanol and food reinforcers were delivered according to resetting DRO schedules. Ethanol and food reinforcers were suspended during resurgence test phases to evaluate resurgence following voluntary abstinence. Lever pressing was elevated during baseline phases and occurred at near-zero rates during DRO phases. During the resurgence test phases, lever pressing increased, despite that it no longer produced ethanol. The procedure introduced here may help researchers better understand the variables that affect voluntary abstinence from ethanol seeking and resurgence following voluntary abstinence.


Assuntos
Condicionamento Operante , Comportamento de Procura de Droga , Etanol , Extinção Psicológica , Reforço Psicológico , Animais , Ratos , Masculino , Esquema de Reforço , Autoadministração/psicologia , Recidiva , Ratos Long-Evans
20.
Inorg Chem ; 63(21): 9638-9647, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38446786

RESUMO

A monoanionic phosphoramide ligand is introduced, which forms a series of lanthanum complexes with the ligand in both anionic and neutral forms. Stoichiometric control alone provides monometallic complexes with either two or three phosphoramide ligands. Alternatively, a combination of anionic and neutral proteo ligands featuring intramolecular hydrogen bonding can be obtained. The anionic form of the ligand binds lanthanum as a bi- or monodentate ligand, depending on the steric demand at the metal center, while the protonated ligand binds exclusively through the phosphoramide oxygen donor.

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