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1.
Nature ; 621(7978): 306-311, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37704765

RESUMO

Nearly all adhesives1,2 are derived from petroleum, create permanent bonds3, frustrate materials separation for recycling4,5 and prevent degradation in landfills. When trying to shift from petroleum feedstocks to a sustainable materials ecosystem, available options suffer from low performance, high cost or lack of availability at the required scales. Here we present a sustainably sourced adhesive system, made from epoxidized soy oil, malic acid and tannic acid, with performance comparable to that of current industrial products. Joints can be cured under conditions ranging from use of a hair dryer for 5 min to an oven at 180 °C for 24 h. Adhesion between metal substrates up to around 18 MPa is achieved, and, in the best cases, performance exceeds that of a classic epoxy, the strongest modern adhesive. All components are biomass derived, low cost and already available in large quantities. Manufacturing at scale can be a simple matter of mixing and heating, suggesting that this new adhesive may contribute towards the sustainable bonding of materials.

2.
Nature ; 606(7916): 884-889, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35512730

RESUMO

Solid-state spin qubits is a promising platform for quantum computation and quantum networks1,2. Recent experiments have demonstrated high-quality control over multi-qubit systems3-8, elementary quantum algorithms8-11 and non-fault-tolerant error correction12-14. Large-scale systems will require using error-corrected logical qubits that are operated fault tolerantly, so that reliable computation becomes possible despite noisy operations15-18. Overcoming imperfections in this way remains an important outstanding challenge for quantum science15,19-27. Here, we demonstrate fault-tolerant operations on a logical qubit using spin qubits in diamond. Our approach is based on the five-qubit code with a recently discovered flag protocol that enables fault tolerance using a total of seven qubits28-30. We encode the logical qubit using a new protocol based on repeated multi-qubit measurements and show that it outperforms non-fault-tolerant encoding schemes. We then fault-tolerantly manipulate the logical qubit through a complete set of single-qubit Clifford gates. Finally, we demonstrate flagged stabilizer measurements with real-time processing of the outcomes. Such measurements are a primitive for fault-tolerant quantum error correction. Although future improvements in fidelity and the number of qubits will be required to suppress logical error rates below the physical error rates, our realization of fault-tolerant protocols on the logical-qubit level is a key step towards quantum information processing based on solid-state spins.

3.
Nature ; 580(7805): 653-657, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32350464

RESUMO

The aboveground parts of terrestrial plants, collectively called the phyllosphere, have a key role in the global balance of atmospheric carbon dioxide and oxygen. The phyllosphere represents one of the most abundant habitats for microbiota colonization. Whether and how plants control phyllosphere microbiota to ensure plant health is not well understood. Here we show that the Arabidopsis quadruple mutant (min7 fls2 efr cerk1; hereafter, mfec)1, simultaneously defective in pattern-triggered immunity and the MIN7 vesicle-trafficking pathway, or a constitutively activated cell death1 (cad1) mutant, carrying a S205F mutation in a membrane-attack-complex/perforin (MACPF)-domain protein, harbour altered endophytic phyllosphere microbiota and display leaf-tissue damage associated with dysbiosis. The Shannon diversity index and the relative abundance of Firmicutes were markedly reduced, whereas Proteobacteria were enriched in the mfec and cad1S205F mutants, bearing cross-kingdom resemblance to some aspects of the dysbiosis that occurs in human inflammatory bowel disease. Bacterial community transplantation experiments demonstrated a causal role of a properly assembled leaf bacterial community in phyllosphere health. Pattern-triggered immune signalling, MIN7 and CAD1 are found in major land plant lineages and are probably key components of a genetic network through which terrestrial plants control the level and nurture the diversity of endophytic phyllosphere microbiota for survival and health in a microorganism-rich environment.


Assuntos
Arabidopsis/genética , Arabidopsis/microbiologia , Redes Reguladoras de Genes/genética , Componentes Aéreos da Planta/genética , Componentes Aéreos da Planta/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/prevenção & controle , Arabidopsis/imunologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Morte Celular , Meio Ambiente , Firmicutes/genética , Firmicutes/isolamento & purificação , Genes de Plantas/genética , Genótipo , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Homeostase , Microbiota/genética , Microbiota/fisiologia , Mutação , Fenótipo , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Imunidade Vegetal/genética , Folhas de Planta/genética , Folhas de Planta/microbiologia , Proteobactérias/genética , Proteobactérias/isolamento & purificação
4.
Proc Natl Acad Sci U S A ; 120(42): e2309688120, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37819984

RESUMO

Whether supervised or unsupervised, human and machine learning is usually characterized as event-based. However, learning may also proceed by systems alignment in which mappings are inferred between entire systems, such as visual and linguistic systems. Systems alignment is possible because items that share similar visual contexts, such as a car and a truck, will also tend to share similar linguistic contexts. Because of the mirrored similarity relationships across systems, the visual and linguistic systems can be aligned at some later time absent either input. In a series of simulation studies, we considered whether children's early concepts support systems alignment. We found that children's early concepts are close to optimal for inferring novel concepts through systems alignment, enabling agents to correctly infer more than 85% of visual-word mappings absent supervision. One possible explanation for why children's early concepts support systems alignment is that they are distinguished structurally by their dense semantic neighborhoods. Artificial agents using these structural features to select concepts proved highly effective, both in environments mirroring children's conceptual world and those that exclude the concepts that children commonly acquire. For children, systems alignment and event-based learning likely complement one another. Likewise, artificial systems can benefit from incorporating these developmental principles.


Assuntos
Linguística , Semântica , Humanos , Criança , Simulação por Computador , Características de Residência
5.
Immunity ; 44(4): 875-88, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27096318

RESUMO

Gut microbiota profoundly affect gut and systemic diseases, but the mechanism whereby microbiota affect systemic diseases is unclear. It is not known whether specific microbiota regulate T follicular helper (Tfh) cells, whose excessive responses can inflict antibody-mediated autoimmunity. Using the K/BxN autoimmune arthritis model, we demonstrated that Peyer's patch (PP) Tfh cells were essential for gut commensal segmented filamentous bacteria (SFB)-induced systemic arthritis despite the production of auto-antibodies predominantly occurring in systemic lymphoid tissues, not PPs. We determined that SFB, by driving differentiation and egress of PP Tfh cells into systemic sites, boosted systemic Tfh cell and auto-antibody responses that exacerbated arthritis. SFB induced PP Tfh cell differentiation by limiting the access of interleukin 2 to CD4(+) T cells, thereby enhancing Tfh cell master regulator Bcl-6 in a dendritic cell-dependent manner. These findings showed that gut microbiota remotely regulated a systemic disease by driving the induction and egress of gut Tfh cells.


Assuntos
Artrite/imunologia , Diferenciação Celular/imunologia , Movimento Celular/imunologia , Microbioma Gastrointestinal/imunologia , Nódulos Linfáticos Agregados/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Autoanticorpos/imunologia , Doenças Autoimunes/imunologia , Linfócitos B/imunologia , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/imunologia , Células Dendríticas/imunologia , Interleucina-2/imunologia , Subunidade alfa de Receptor de Interleucina-2/genética , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Nódulos Linfáticos Agregados/citologia , Proteínas Proto-Oncogênicas c-bcl-6 , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T Auxiliares-Indutores/citologia
6.
J Immunol ; 210(12): 2029-2037, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37163328

RESUMO

The intrinsic and acquired resistance to PD-1/PD-L1 immune checkpoint blockade is an important challenge for patients and clinicians because no reliable tool has been developed to predict individualized response to immunotherapy. In this study, we demonstrate the translational relevance of an ex vivo functional assay that measures the tumor cell killing ability of patient-derived CD8 T and NK cells (referred to as "cytotoxic lymphocytes," or CLs) isolated from the peripheral blood of patients with renal cell carcinoma. Patient-derived PBMCs were isolated before and after nephrectomy from patients with renal cell carcinoma. We compared the efficacy of U.S. Food and Drug Administration (FDA)-approved PD-1/PD-L1 inhibitors (pembrolizumab, nivolumab, atezolizumab) and a newly developed PD-L1 inhibitor (H1A Ab) in eliciting cytotoxic function. CL activity was improved at 3 mo after radical nephrectomy compared with baseline, and it was associated with higher circulating levels of tumor-reactive effector CD8 T cells (CD11ahighCX3CR1+GZMB+). Treatment of PBMCs with FDA-approved PD-1/PD-L1 inhibitors enhanced tumor cell killing activity of CLs, but a differential response was observed at the individual-patient level. H1A demonstrated superior efficacy in promoting CL activity compared with FDA-approved PD-1/PD-L1 inhibitors. PBMC immunophenotyping by mass cytometry revealed enrichment of effector CD8 T and NK cells in H1A-treated PBMCs and immunosuppressive regulatory T cells in atezolizumab-treated samples. Our study lays the ground for future investigation of the therapeutic value of H1A as a next-generation immune checkpoint inhibitor and the potential of measuring CTL activity in PBMCs as a tool to predict individual response to immune checkpoint inhibitors in patients with advanced renal cell carcinoma.


Assuntos
Antineoplásicos , Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Antígeno B7-H1 , Receptor de Morte Celular Programada 1 , Leucócitos Mononucleares , Antineoplásicos/farmacologia , Linfócitos T Reguladores , Neoplasias Renais/tratamento farmacológico , Nefrectomia , Linfócitos T CD8-Positivos
7.
Nature ; 576(7787): 411-415, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31853078

RESUMO

Nuclear magnetic resonance (NMR) is a powerful method for determining the structure of molecules and proteins1. Whereas conventional NMR requires averaging over large ensembles, recent progress with single-spin quantum sensors2-9 has created the prospect of magnetic imaging of individual molecules10-13. As an initial step towards this goal, isolated nuclear spins and spin pairs have been mapped14-21. However, large clusters of interacting spins-such as those found in molecules-result in highly complex spectra. Imaging these complex systems is challenging because it requires high spectral resolution and efficient spatial reconstruction with sub-ångström precision. Here we realize such atomic-scale imaging using a single nitrogen vacancy centre as a quantum sensor, and demonstrate it on a model system of 27 coupled 13C nuclear spins in diamond. We present a multidimensional spectroscopy method that isolates individual nuclear-nuclear spin interactions with high spectral resolution (less than 80 millihertz) and high accuracy (2 millihertz). We show that these interactions encode the composition and inter-connectivity of the cluster, and develop methods to extract the three-dimensional structure of the cluster with sub-ångström resolution. Our results demonstrate a key capability towards magnetic imaging of individual molecules and other complex spin systems9-13.

8.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38041253

RESUMO

Closed-loop direct brain stimulation is a promising tool for modulating neural activity and behavior. However, it remains unclear how to optimally target stimulation to modulate brain activity in particular brain networks that underlie particular cognitive functions. Here, we test the hypothesis that stimulation's behavioral and physiological effects depend on the stimulation target's anatomical and functional network properties. We delivered closed-loop stimulation as 47 neurosurgical patients studied and recalled word lists. Multivariate classifiers, trained to predict momentary lapses in memory function, triggered the stimulation of the lateral temporal cortex (LTC) during the study phase of the task. We found that LTC stimulation specifically improved memory when delivered to targets near white matter pathways. Memory improvement was largest for targets near white matter that also showed high functional connectivity to the brain's memory network. These targets also reduced low-frequency activity in this network, an established marker of successful memory encoding. These data reveal how anatomical and functional networks mediate stimulation's behavioral and physiological effects, provide further evidence that closed-loop LTC stimulation can improve episodic memory, and suggest a method for optimizing neuromodulation through improved stimulation targeting.


Assuntos
Imageamento por Ressonância Magnética , Memória Episódica , Humanos , Encéfalo/fisiologia , Rememoração Mental/fisiologia , Mapeamento Encefálico
9.
Annu Rev Psychol ; 75: 215-240, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-37562499

RESUMO

Similarity and categorization are fundamental processes in human cognition that help complex organisms make sense of the cacophony of information in their environment. These processes are critical for tasks such as recognizing objects, making decisions, and forming memories. In this review, we provide an overview of the current state of knowledge on similarity and psychological spaces, discussing the theories, methods, and empirical findings that have been generated over the years. Although the concept of similarity has important limitations, it plays a key role in cognitive modeling. The review surfaces three key themes. First, similarity and mental representations are merely two sides of the same coin, existing as a similarity-representation duality that defines a psychological space. Second, both the brain's mental representations and the study of mental representations are made possible by exploiting second-order isomorphism. Third, similarity analysis has near-universal applicability across all levels of cognition, providing a common research language.


Assuntos
Cognição , Idioma , Humanos
10.
Lancet Oncol ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38942046

RESUMO

BACKGROUND: The standard of care for patients with intermediate-to-high risk renal cell carcinoma is partial or radical nephrectomy followed by surveillance. We aimed to investigate use of nivolumab before nephrectomy followed by adjuvant nivolumab in patients with high-risk renal cell carcinoma to determine recurrence-free survival compared with surgery only. METHODS: In this open-label, randomised, phase 3 trial (PROSPER EA8143), patients were recruited from 183 community and academic sites across the USA and Canada. Eligible patients were aged 18 years or older with an Eastern Cooperative Oncology Group performance status of 0-1, with previously untreated clinical stage T2 or greater or Tany N+ renal cell carcinoma of clear cell or non-clear cell histology planned for partial or radical nephrectomy. Selected patients with oligometastatic disease, who were disease free at other disease sites within 12 weeks of surgery, were eligible for inclusion. We randomly assigned (1:1) patients using permuted blocks (block size of 4) within stratum (clinical TNM stage) to either nivolumab plus surgery, or surgery only followed by surveillance. In the nivolumab group, nivolumab 480 mg was administered before surgery, followed by nine adjuvant doses. The primary endpoint was investigator-reviewed recurrence-free survival in patients with renal cell carcinoma assessed in all randomly assigned patients regardless of histology. Safety was assessed in all randomly assigned patients who started the assigned protocol treatment. This trial is registered with ClinicalTrials.gov, NCT03055013, and is closed to accrual. FINDINGS: Between Feb 2, 2017, and June 2, 2021, 819 patients were randomly assigned to nivolumab plus surgery (404 [49%]) or surgery only (415 [51%]). 366 (91%) of 404 patients assigned to nivolumab plus surgery and 387 (93%) of 415 patients assigned to surgery only group started treatment. Median age was 61 years (IQR 53-69), 248 (30%) of 819 patients were female, 571 (70%) were male, 672 (88%) were White, and 77 (10%) were Hispanic or Latino. The Data and Safety Monitoring Committee stopped the trial at a planned interim analysis (March 25, 2022) because of futility. Median follow-up was 30·4 months (IQR 21·5-42·4) in the nivolumab group and 30·1 months (21·9-41·8) in the surgery only group. 381 (94%) of 404 patients in the nivolumab plus surgery group and 399 (96%) of 415 in the surgery only group had renal cell carcinoma and were included in the recurrence-free survival analysis. As of data cutoff (May 24, 2023), recurrence-free survival was not significantly different between nivolumab (125 [33%] of 381 had recurrence-free survival events) versus surgery only (133 [33%] of 399; hazard ratio 0·94 [95% CI 0·74-1·21]; one-sided p=0·32). The most common treatment-related grade 3-4 adverse events were elevated lipase (17 [5%] of 366 patients in the nivolumab plus surgery group vs none in the surgery only group), anaemia (seven [2%] vs nine [2%]), increased alanine aminotransferase (ten [3%] vs one [<1%]), abdominal pain (four [1%] vs six [2%]), and increased serum amylase (nine [2%] vs none). 177 (48%) patients in the nivolumab plus surgery group and 93 (24%) in the surgery only group had grade 3-5 adverse events due to any cause, the most common of which were anaemia (23 [6%] vs 19 [5%]), hypertension (27 [7%] vs nine [2%]), and elevated lipase (18 [5%] vs six [2%]). 48 (12%) of 404 patients in the nivolumab group and 40 (10%) of 415 in the surgery only group died, of which eight (2%) and three (1%), respectively, were determined to be treatment-related. INTERPRETATION: Perioperative nivolumab before nephrectomy followed by adjuvant nivolumab did not improve recurrence-free survival versus surgery only followed by surveillance in patients with high-risk renal cell carcinoma. FUNDING: US National Institutes of Health National Cancer Institute and Bristol Myers Squibb.

11.
Am J Physiol Renal Physiol ; 326(3): F352-F368, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38095025

RESUMO

Our research has shown that interventions producing a state of ketosis are highly effective in rat, mouse, and cat models of polycystic kidney disease (PKD), preventing and partially reversing cyst growth and disease progression. The ketone ß-hydroxybutyrate (BHB) appears to underlie this effect. In addition, we have demonstrated that naturally formed microcrystals within kidney tubules trigger a renoprotective response that facilitates tubular obstruction clearance in healthy animals but, alternatively, leads to cyst formation in PKD. The administration of citrate prevents microcrystal formation and slows PKD progression. Juvenile Cy/+ rats, a nonorthologous PKD model, were supplemented from 3 to 8 wk of age with water containing titrated BHB, citrate, or in combination to find minimal effective and optimal dosages, respectively. Adult rats were given a reduced BHB/citrate combination or equimolar control K/NaCl salts from 8 to 12 wk of age. In addition, adult rats were placed in metabolic cages following BHB, citrate, and BHB/citrate administration to determine the impact on mineral, creatinine, and citrate excretion. BHB or citrate alone effectively ameliorates disease progression in juvenile rats, decreasing markers of cystic disease and, in combination, producing a synergistic effect. BHB/citrate leads to partial disease regression in adult rats with established cystic disease, inhibiting cyst formation and kidney injury. BHB/citrate confers benefits via multiple mechanisms, increases creatinine and citrate excretion, and normalizes mineral excretion. BHB and citrate are widely available and generally recognized as safe compounds and, in combination, exhibit high promise for supporting kidney health in polycystic kidney disease.NEW & NOTEWORTHY Combining ß-hydroxybutyrate (BHB) and citrate effectively slows and prevents cyst formation and expansion in young Cy/+ rats using less BHB and citrate than when used alone, demonstrating synergy. In adult rats, the combination causes a partial reversal of existing disease, reducing cyst number and cystic area, preserving glomerular health, and decreasing markers of kidney injury. Our results suggest a safe and feasible strategy for supporting kidney health in polycystic kidney disease (PKD) using a combination of BHB and citrate.


Assuntos
Cistos , Doenças Renais Policísticas , Animais , Ratos , Ácido 3-Hidroxibutírico/farmacologia , Citratos/farmacologia , Citratos/uso terapêutico , Ácido Cítrico , Creatinina , Modelos Animais de Doenças , Progressão da Doença , Minerais , Doenças Renais Policísticas/tratamento farmacológico , Doenças Renais Policísticas/metabolismo
12.
Cancer ; 130(9): 1642-1649, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38180804

RESUMO

INTRODUCTION: Programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) blockade has changed the landscape of treatment for metastatic urothelial cancer, but single-agent cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) blockade in metastatic urothelial cancer has been underexplored. A prior phase 2 trial of tremelimumab in PD-1/PD-L1-blockade naive patients with metastatic urothelial cancer revealed activity comparable to that observed with PD-1/PD-L1 blockade raising the hypothesis that these classes of immune checkpoint inhibitors might be non-cross-resistant. METHODS: The current phase 2 trial treated patients with PD-1/PD-L1 blockade-resistant metastatic urothelial cancer with single-agent tremelimumab (750 mg intravenously every 28 days for up to 7 cycles). The primary end point was objective response rate. RESULTS: Twenty-six patients were enrolled and 24 patients were evaluable for response. The objective response rate was 8.3%, composed of a total of two partial responses that lasted 10.9 and 24.0 months. Stable disease was observed in another 20.8% of patients, with a median duration of stable disease of 5.4 months. Diarrhea occurred in 15 patients (58%), elevated hepatic transaminases occurred in seven patients (27%), and adrenal insufficiency occurred in two patients (8%); one patient died after experiencing immune-related hepatitis. CONCLUSIONS: High dose CTLA-4 blockade in patients with PD-1/PD-L1-resistant metastatic urothelial cancer has modest activity and is associated with treatment-related toxicity similar to prior reports.


Assuntos
Anticorpos Monoclonais Humanizados , Antígeno B7-H1 , Carcinoma de Células de Transição , Humanos , Anticorpos Monoclonais Humanizados/uso terapêutico , Carcinoma de Células de Transição/tratamento farmacológico , Antígeno CTLA-4 , Receptor de Morte Celular Programada 1 , Inibidores de Checkpoint Imunológico/uso terapêutico
13.
Cancer ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38959291

RESUMO

BACKGROUND: Bladder cancer with divergent differentiation (BCDD) comprises a heterogenous group of tumors with a poor prognosis, and differential expression of nectin-4 and programmed death ligand-1 (PD-L1) has been reported in BCDD. Importantly, nectin-4 expression in bladder cancer is associated with response to enfortumab vedotin, and PD-L1 expression is associated with responses to immune checkpoint inhibitors (ICIs). METHODS: The authors conducted a retrospective review identifying 117 patients with advanced or metastatic BCDD who were treated at Winship Cancer Institute from 2011 to 2021. They performed immunohistochemistry staining for nectin-4 and PD-L1 expression by histologic subtype as well as genomic analysis of these patients, including RNA sequencing, whole-exome sequencing, and fusion detection analysis as well as a subgroup genomic analysis of patients with BCDD who received ICIs. RESULTS: The results indicated that nectin-4 expression was highest in the groups who had the squamous and plasmacytoid subtypes, whereas the group that had the sarcomatoid subtype (70.8%) had the highest proportion of PD-L1-positive patients. Genomic analysis yielded several key findings, including a 50% RB1 mutation rate in patients who had small cell BCDD, targetable PIK3CA mutations across multiple subtypes of BCDD, and significantly higher expression of TEC in responders to ICIs. CONCLUSIONS: In this study, the authors identified clinically relevant data on nectin-4 and PD-L1 expression in patients with rare bladder tumors. They also identified several novel findings in the genomic analysis that highlight the role of precision medicine in this population of patients. Larger, prospective studies are needed to validate these hypothesis-generating data.

14.
J Urol ; 212(2): 331-341, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38813884

RESUMO

PURPOSE: The AUA guidelines introduced a new risk group stratification system based primarily on tumor stage and grade to guide surveillance for patients treated surgically for localized renal cell carcinoma (RCC). We sought to evaluate the predictive ability of these risk groups using progression-free survival (PFS) and cancer-specific survival (CSS), and to compare their performance to that of our published institutional risk models. MATERIALS AND METHODS: We queried our Nephrectomy Registry to identify adults treated with radical or partial nephrectomy for unilateral, M0, clear cell RCC, or papillary RCC from 1980 to 2012. The AUA stratification does not apply to other RCC subtypes as tumor grading for other RCC, such as chromophobe, is not routinely performed. PFS and CSS were estimated using the Kaplan-Meier method. Predictive abilities were evaluated using C indexes from Cox proportional hazards regression models. RESULTS: A total of 3191 patients with clear cell RCC and 633 patients with papillary RCC were included. For patients with clear cell RCC, C indexes for the AUA risk groups and our model were 0.780 and 0.815, respectively (P < .001) for PFS, and 0.811 and 0.857, respectively (P < .001), for CSS. For patients with papillary RCC, C indexes for the AUA risk groups and our model were 0.775 and 0.751, respectively (P = .002) for PFS, and 0.830 and 0.803, respectively (P = .2) for CSS. CONCLUSIONS: The AUA stratification is a parsimonious system for categorizing RCC that provides C indexes of about 0.80 for PFS and CSS following surgery for localized clear cell and papillary RCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Nefrectomia , Humanos , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/cirurgia , Carcinoma de Células Renais/mortalidade , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Neoplasias Renais/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Medição de Risco/métodos , Nefrectomia/métodos , Idoso , Estudos Retrospectivos , Estadiamento de Neoplasias , Sistema de Registros , Guias de Prática Clínica como Assunto , Adulto , Taxa de Sobrevida
15.
J Urol ; : 101097JU0000000000004124, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935793

RESUMO

PURPOSE: AUA guidelines prioritize nephron sparing in patients with preexisting chronic kidney disease (CKD). However, few studies analyze long-term renal function in patients with preoperative severe CKD who undergo extirpative renal surgery. Herein, we compare the hazard of progression to end-stage kidney disease (ESKD) following partial nephrectomy (PN) and radical nephrectomy (RN) among patients with preoperative severe CKD. MATERIALS AND METHODS: Patients with stage 4 CKD who underwent PN or RN from 1970 to 2018 were identified. A multivariable Fine-Gray subdistribution hazard model was employed to assess associations with progression to ESKD accounting for the competing risk of death. RESULTS: A total of 186 patients with stage 4 CKD underwent PN (n = 71; 38%) or RN (n = 115; 62%) for renal neoplasms with median follow-up of 6.9 years (interquartile range 3.8-14.1). On multivariable analyses adjusting for competing risk of death, the subdistribution hazard ratio (SHR) for older age at surgery (SHR for 5-year increase 0.81; 95% CI 0.73-0.91; P < .001) and higher preoperative estimated glomerular filtration rate (SHR for 5-unit increase 0.63; 95% CI 0.47-0.84; P = .002) was associated with lower hazard of progression to ESKD. There was no significant difference in hazard of ESKD between PN and RN (SHR 0.82; 95% CI 0.50-1.33; P = .4). CONCLUSIONS: Among patients with preoperative severe CKD, higher preoperative estimated glomerular filtration rate was associated with lower hazard of progression to ESKD after extirpative surgery for renal neoplasms. We did not observe a significant difference in overall hazard for developing ESKD between PN and RN.

16.
New Phytol ; 241(2): 715-731, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37932881

RESUMO

Heat stress interrupts physiological thermostability and triggers biochemical responses that are essential for plant survival. However, there is limited knowledge on the speed plants adjust to heat in hours and days, and which adjustments are crucial. Tropical-subtropical rainforest tree species (Polyscias elegans) were heated at 40°C for 5 d, before returning to 25°C for 13 d of recovery. Leaf heat tolerance was quantified using the temperature at which minimal chl a fluorescence sharply rose (Tcrit ). Tcrit , metabolites, heat shock protein (HSP) abundance and membrane lipid fatty acid (FA) composition were quantified. Tcrit increased by 4°C (48-52°C) within 2 h of 40°C exposure, along with rapid accumulation of metabolites and HSPs. By contrast, it took > 2 d for FA composition to change. At least 2 d were required for Tcrit , HSP90, HSP70 and FAs to return to prestress levels. The results highlight the multi-faceted response of P. elegans to heat stress, and how this response varies over the scale of hours to days, culminating in an increased level of photosynthetic heat tolerance. These responses are important for survival of plants when confronted with heat waves amidst ongoing global climate change.


Assuntos
Termotolerância , Proteínas de Choque Térmico/metabolismo , Plantas/metabolismo , Floresta Úmida , Temperatura , Árvores/metabolismo , Clima Tropical
17.
Neurobiol Learn Mem ; 212: 107941, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38768684

RESUMO

Categorization requires a balance of mechanisms that can generalize across common features and discriminate against specific details. A growing literature suggests that the hippocampus may accomplish these mechanisms by using fundamental mechanisms like pattern separation, pattern completion, and memory integration. Here, we assessed the role of the rodent dorsal hippocampus (HPC) in category learning by combining inhibitory DREADDs (Designer Receptors Exclusively Activated by Designer Drugs) and simulations using a neural network model. Using touchscreens, we trained rats to categorize distributions of visual stimuli containing black and white gratings that varied along two continuous dimensions. Inactivating the dorsal HPC impaired category learning and generalization, suggesting that the rodent HPC plays an important role during categorization. Hippocampal inactivation had no effect on a control discrimination task that used identical trial procedures as the categorization tasks, suggesting that the impairments were specific to categorization. Model simulations were conducted with variants of a neural network to assess the impact of selective deficits on category learning. The hippocampal inactivation groups were best explained by a model that injected random noise into the computation that compared the similarity between category stimuli and existing memory representations. This model is akin to a deficit in mechanisms of pattern completion, which retrieves similar memory representations using partial information.


Assuntos
Hipocampo , Animais , Hipocampo/fisiologia , Ratos , Masculino , Ratos Long-Evans , Aprendizagem por Discriminação/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Generalização Psicológica/fisiologia
18.
J Nutr ; 154(4): 1414-1427, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38159813

RESUMO

BACKGROUND: Evidence-based practice (EBP) promotes shared decision-making between clinicians and patients. OBJECTIVE: The aim was to determine EBP competencies among nutrition professionals and students reported in the literature. METHODS: We conducted a systematic review by searching Medline, Embase, CINAHL, ERIC, CENTRAL, ProQuest Dissertations and Theses Global, BIOSIS Citation Index, and clinicaltrials.gov up to March 2023. Eligible primary studies had to assess one of the 6 predefined EBP competencies: formulating clinical questions; searching literature for best evidence; assessing studies for methodological quality; effect size; certainty of evidence for effects; and determining the applicability of study results considering patient values and preferences. Two reviewers independently screened articles and extracted data, and results were summarized for each EBP competency. RESULTS: We identified 12 eligible cross-sectional survey studies, comprising 1065 participants, primarily registered dietitians, across 6 countries, with the majority assessed in the United States (n = 470). The reporting quality of the survey studies was poor overall, with 43% of items not reported. Only 1 study (8%) explicitly used an objective questionnaire to assess EBP competencies. In general, the 6 competencies were incompletely defined or reported (e.g., it was unclear what applicability and critical appraisal referred to and what study designs were appraised by the participants). Two core competencies, interpreting effect size and certainty of evidence for effects, were not assessed. CONCLUSIONS: The overall quality of study reports was poor, and the questionnaires were predominantly self-perceived, as opposed to objective assessments. No studies reported on competencies in interpreting effect size or certainty of evidence, competencies essential for optimizing clinical nutrition decision-making. Future surveys should objectively assess core EBP competencies using sensible, specific questionnaires. Furthermore, EBP competencies need to be standardized across dietetic programs to minimize heterogeneity in the training, understanding, evaluation, and application among dietetics practitioners. This study was registered at PROSPERO as CRD42022311916.


Assuntos
Prática Clínica Baseada em Evidências , Estudantes , Humanos , Estudos Transversais , Prática Clínica Baseada em Evidências/educação , Prática Clínica Baseada em Evidências/métodos , Inquéritos e Questionários
19.
Inorg Chem ; 63(4): 1938-1946, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38232376

RESUMO

The production of ceramics from uranium coordination compounds can be achieved through thermal processing if an excess amount of the desired atoms (i.e., C or N), or reactive gaseous products (e.g., methane or nitrogen oxide) is made available to the reactive uranium metal core via decomposition/fragmentation of the surrounding ligand groups. Here, computational thermodynamic approaches were utilized to identify the temperatures necessary to produce uranium metal from some starting compounds─UI4(TMEDA)2, UCl4(TMEDA)2, UCl3(pyridine)x, and UI3(pyridine)4. Experimentally, precursors were irradiated by a laser under various gaseous environments (argon, nitrogen, and methane) creating extreme reaction conditions (i.e., fast heating, high temperature profile >2000 °C, and rapid cooling). Despite the fast dynamics associated with laser irradiation, the central uranium atom reacted with the thermal decomposition products of the ligands yielding uranium ceramics. Residual gas analysis identified vaporized products from the laser irradiation, and the final ceramic products were characterized by powder X-ray diffraction. The composition of the uranium precursor as well as the gaseous environment had a direct impact on the production of the final phases.

20.
Ann Pharmacother ; : 10600280231222465, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38288555

RESUMO

BACKGROUND: The COVID-19 pandemic has led to a rapid, exponential increase in hospitalizations and morbidity/mortality. In November 2020, the Food and Drug Administration (FDA) issued Emergency Use Authorizations (EUAs) permitting administration of the first monoclonal antibodies (mAb) for outpatient treatment of COVID-19. Early data showed a reduction in COVID-19-related hospitalizations with few adverse events. However, since these treatments are only authorized under an EUA, real-world data are minimal. OBJECTIVE: To assess efficacy and safety of mAbs in a veteran population. METHODS: This retrospective study analyzed veterans at the Ralph H. Johnson Veterans Affairs Health Care System with mild-moderate COVID-19 and screened for mAb eligibility between December 1, 2020, and October 31, 2021. The primary outcome was hospitalizations and/or emergency department (ED) visits within 30 days. Secondary outcomes included 30-day mortality and post-COVID-19 conditions. Adverse events were also evaluated. Outcomes were compared between mAb-treated patients and eligible veterans who were not treated. RESULTS: There were 296 and 275 veterans in the mAb and control groups, respectively. No statistically significant difference was found for the primary outcome overall (25.7% vs 25.1%; P = 0.87), nor for COVID-19-related return visits or hospitalizations (13.9% v. 16%; P = 0.4). However, the mAb group had more return ED visits (P = 0.35), and the control group had significantly more hospitalizations (P = 0.02). Vaccinated veterans who received an mAb had fewer return visits and hospitalizations (P = 0.01). More mAb-treated veterans experienced post-COVID-19 conditions. No difference in mortality was found. Four nonsevere adverse events occurred after the mAb therapy. CONCLUSION AND RELEVANCE: Overall, the mAbs appeared safe and effective. Sicker, higher-risk mAb-treated veterans faired similarly to less-sick, high-risk veterans not treated. Those who were vaccinated seemed to benefit the most from mAb therapy. Future prospective studies with more matched groups are needed to assess full benefits and risks of mAbs shown to neutralize the predominant variants.

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