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1.
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.

2.
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).

3.
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.

4.
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.

5.
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
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.
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.

9.
JAMA Oncol ; 2024 Apr 11.
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.

10.
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.

11.
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.

12.
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
13.
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
14.
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
15.
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.

16.
Neurooncol Pract ; 11(2): 199-204, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38496920

RESUMO

Background: Isocitrate dehydrogenase (IDH) is commonly mutated (mIDH) in gliomas, and this mutant enzyme produces the oncometabolite 2-hydroxyglutarate (2HG). 2HG promotes gliomagenesis and is implicated in epileptogenesis. Ivosidenib (IVO), a small molecule oral mIDH1 inhibitor, is FDA-approved for mIDH1 newly diagnosed and relapsed/refractory acute myeloid leukemia. Moreover, IVO has efficacy in clinical trials for recurrent mIDH1 gliomas. Given the lack of targeted treatments for gliomas, we initiated off-label IVO for mIDH glioma patients in October 2020. Methods: Retrospectively, we sought to assess early outcomes in our patients and describe their experience on IVO from October 2020 through February 2022. Our objective was to report on the following variables of off-label use of IVO: radiographic response, seizure control, tolerability, and access to the medication. All patients initially received single-agent IVO dosed at 500 mg orally once daily. Results: The cohort age range was 21-74 years. Tumor types included astrocytoma (n = 14) and oligodendroglioma (n = 16), with most being grade 2 (n = 21). The best radiographic response in nonenhancing disease (n = 22) was 12 stable diseases, 5 minor responses, 3 partial responses, and 2 progressive diseases. Seizure frequency was stable to improved for most patients (70%, n = 21). IVO was well-tolerated, with the most common toxicities being diarrhea, elevated creatine kinase, and QTc interval prolongation. Most patients (66.7%, n = 20) received drugs via the patient assistance program, with insurance initially covering a third of patients and with ongoing use, later covering 60%. Conclusions: Targeted therapies like IVO are options for mIDH glioma patients and can provide positive oncologic and neurological outcomes.

17.
Laryngoscope ; 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38411338

RESUMO

OBJECTIVE(S): Describe recent national trends in overall treatment modalities for T1 glottic squamous cell carcinomas (SCC), and identify factors associated with treatment regimens. METHODS: National Cancer Database from 2004-2020 was queried for all patients with glottic cT1N0M0 SCC. Treatment patterns over time were analyzed using the Cochran-Armitage test for trend. Multivariable logistic regressions were used to determine the factors associated with treatment regimens. RESULTS: Of the 22,414 patients identified, most patients received RT only (57%), 21% received surgery only, and 22% received dual-modality treatment ("over-treatment"). Over the time period, there was a decreasing trend in rates of over-treatment for T1 glottic SCC (p < 0.001) and an increasing trend in surgery only (p < 0.001). Treatment in 2016-2018 (OR: 1.168 [1.004 to 1.359]), 2013-2015 (OR: 1.419 [1.221 to 1.648]), 2010-2012 (OR: 1.611 [1.388 to 1.871]), 2007-2009 (OR: 1.682 [1.450 to 1.951]), or 2004-2006 (OR: 1.795 [1.548 to 2.081]) versus 2019-2020 was associated with greater likelihood of over-treatment. T1b tumors were less likely to be over-treated (OR: 0.795 [0.707 to 0.894]) versus T1a tumors, and less likely to receive surgery first (OR: 0.536 [0.485 to 0.592]) versus T1a tumors. CONCLUSION: Over-treatment for T1 glottic SCC has been declining, with increasing rates of surgery only. Year of treatment was significantly associated with the receipt of dual-modality treatment. Finally, patients with T1b disease were more likely to receive RT as the first and only treatment. LEVEL OF EVIDENCE: 3 Laryngoscope, 2024.

18.
Protein Sci ; 33(3): e4898, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38358135

RESUMO

Structural genomics consortia established that protein crystallization is the primary obstacle to structure determination using x-ray crystallography. We previously demonstrated that crystallization propensity is systematically related to primary sequence, and we subsequently performed computational analyses showing that arginine is the most overrepresented amino acid in crystal-packing interfaces in the Protein Data Bank. Given the similar physicochemical characteristics of arginine and lysine, we hypothesized that multiple lysine-to-arginine (KR) substitutions should improve crystallization. To test this hypothesis, we developed software that ranks lysine sites in a target protein based on the redundancy-corrected KR substitution frequency in homologs. This software can be run interactively on the worldwide web at https://www.pxengineering.org/. We demonstrate that three unrelated single-domain proteins can tolerate 5-11 KR substitutions with at most minor destabilization, and, for two of these three proteins, the construct with the largest number of KR substitutions exhibits significantly enhanced crystallization propensity. This approach rapidly produced a 1.9 Å crystal structure of a human protein domain refractory to crystallization with its native sequence. Structures from Bulk KR-substituted domains show the engineered arginine residues frequently make hydrogen-bonds across crystal-packing interfaces. We thus demonstrate that Bulk KR substitution represents a rational and efficient method for probabilistic engineering of protein surface properties to improve crystallization.


Assuntos
Lisina , Proteínas , Humanos , Lisina/química , Cristalização , Proteínas/genética , Aminoácidos/química , Cristalografia por Raios X , Arginina/metabolismo
20.
J Am Chem Soc ; 146(8): 5560-5568, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38373439

RESUMO

There are several reports of compounds containing lanthanide ions in two different formal oxidation states; however, there are strikingly few examples of intervalence charge transfer (IVCT) transitions observed for these complexes, with those few occurrences limited to extended solids rather than molecular species. Herein, we report the synthesis, characterization, and computational analysis for a series of ytterbium complexes including a mixed-valence Yb25+ complex featuring a remarkably short Yb···Yb distance of 2.9507(8) Å. In contrast to recent reports of short Ln···Ln distances attributed to bonding through 5d orbitals, the formally Yb25+ complex presented here displays clear localization of Ln2+ and Ln3+ character and yet still displays an IVCT in the visible spectrum. These results demonstrate the ability to tune the electronic structure of formally mixed oxidation state lanthanide complexes: the high exchange stabilization of the Yb2+ 4f14 configuration disfavors the formation of a 5d1 bonding configuration, and the short metal-metal distance enforced by the ligand framework allows for the first observed lanthanide IVCT in a molecular system.

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