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1.
Nature ; 598(7879): 39-48, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34616053

RESUMO

Mechanical mechanisms have been used to process information for millennia, with famous examples ranging from the Antikythera mechanism of the Ancient Greeks to the analytical machines of Charles Babbage. More recently, electronic forms of computation and information processing have overtaken these mechanical forms, owing to better potential for miniaturization and integration. However, several unconventional computing approaches have recently been introduced, which blend ideas of information processing, materials science and robotics. This has raised the possibility of new mechanical computing systems that augment traditional electronic computing by interacting with and adapting to their environment. Here we discuss the use of mechanical mechanisms, and associated nonlinearities, as a means of processing information, with a view towards a framework in which adaptable materials and structures act as a distributed information processing network, even enabling information processing to be viewed as a material property, alongside traditional material properties such as strength and stiffness. We focus on approaches to abstract digital logic in mechanical systems, discuss how these systems differ from traditional electronic computing, and highlight the challenges and opportunities that they present.

2.
Nature ; 585(7823): 102-106, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32848245

RESUMO

Accumulating evidence indicates that gut microorganisms have a pathogenic role in autoimmune diseases, including in multiple sclerosis1. Studies of experimental autoimmune encephalomyelitis (an animal model of multiple sclerosis)2,3, as well as human studies4-6, have implicated gut microorganisms in the development or severity of multiple sclerosis. However, it remains unclear how gut microorganisms act on the inflammation of extra-intestinal tissues such as the spinal cord. Here we show that two distinct signals from gut microorganisms coordinately activate autoreactive T cells in the small intestine that respond specifically to myelin oligodendrocyte glycoprotein (MOG). After induction of experimental autoimmune encephalomyelitis in mice, MOG-specific CD4+ T cells are observed in the small intestine. Experiments using germ-free mice that were monocolonized with microorganisms from the small intestine demonstrated that a newly isolated strain in the family Erysipelotrichaceae acts similarly to an adjuvant to enhance the responses of T helper 17 cells. Shotgun sequencing of the contents of the small intestine revealed a strain of Lactobacillus reuteri that possesses peptides that potentially mimic MOG. Mice that were co-colonized with these two strains showed experimental autoimmune encephalomyelitis symptoms that were more severe than those of germ-free or monocolonized mice. These data suggest that the synergistic effects that result from the presence of these microorganisms should be considered in the pathogenicity of multiple sclerosis, and that further study of these microorganisms may lead to preventive strategies for this disease.


Assuntos
Encefalomielite Autoimune Experimental/microbiologia , Microbioma Gastrointestinal/imunologia , Inflamação/patologia , Medula Espinal/patologia , Linfócitos T/imunologia , Linfócitos T/patologia , Animais , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Encefalomielite Autoimune Experimental/prevenção & controle , Feminino , Vida Livre de Germes , Inflamação/imunologia , Intestino Delgado/imunologia , Intestino Delgado/microbiologia , Intestino Delgado/patologia , Limosilactobacillus reuteri/química , Limosilactobacillus reuteri/imunologia , Limosilactobacillus reuteri/patogenicidade , Masculino , Camundongos , Esclerose Múltipla/imunologia , Esclerose Múltipla/microbiologia , Esclerose Múltipla/patologia , Glicoproteína Mielina-Oligodendrócito/química , Glicoproteína Mielina-Oligodendrócito/imunologia , Medula Espinal/imunologia , Células Th17/imunologia , Células Th17/patologia
3.
Proc Natl Acad Sci U S A ; 120(17): e2206975120, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37068259

RESUMO

Living bio-nano systems for artificial photosynthesis are of growing interest. Typically, these systems use photoinduced charge transfer to provide electrons for microbial metabolic processes, yielding a biosynthetic solar fuel. Here, we demonstrate an entirely different approach to constructing a living bio-nano system, in which electrogenic bacteria respire semiconductor nanoparticles to support nanoparticle photocatalysis. Semiconductor nanocrystals are highly active and robust photocatalysts for hydrogen (H2) evolution, but their use is hindered by the oxidative side of the reaction. In this system, Shewanella oneidensis MR-1 provides electrons to a CdSe nanocrystalline photocatalyst, enabling visible light-driven H2 production. Unlike microbial electrolysis cells, this system requires no external potential. Illuminating this system at 530 nm yields continuous H2 generation for 168 h, which can be lengthened further by replenishing bacterial nutrients.


Assuntos
Compostos de Cádmio , Pontos Quânticos , Compostos de Selênio , Shewanella , Pontos Quânticos/química , Compostos de Cádmio/química , Hidrogênio/metabolismo , Compostos de Selênio/química , Compostos de Selênio/metabolismo , Shewanella/metabolismo
4.
Mol Psychiatry ; 29(4): 1114-1127, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38177353

RESUMO

The discovery that subanesthetic doses of (R, S)-ketamine (ketamine) and (S)-ketamine (esketamine) rapidly induce antidepressant effects and promote sustained actions following drug clearance in depressed patients who are treatment-resistant to other therapies has resulted in a paradigm shift in the conceptualization of how rapidly and effectively depression can be treated. Consequently, the mechanism(s) that next generation antidepressants may engage to improve pathophysiology and resultant symptomology are being reconceptualized. Impaired excitatory glutamatergic synapses in mood-regulating circuits are likely a substantial contributor to the pathophysiology of depression. Metaplasticity is the process of regulating future capacity for plasticity by priming neurons with a stimulation that alters later neuronal plasticity responses. Accordingly, the development of treatment modalities that specifically modulate the duration, direction, or magnitude of glutamatergic synaptic plasticity events such as long-term potentiation (LTP), defined here as metaplastogens, may be an effective approach to reverse the pathophysiology underlying depression and improve depression symptoms. We review evidence that the initiating mechanisms of pharmacologically diverse rapid-acting antidepressants (i.e., ketamine mimetics) converge on consistent downstream molecular mediators that facilitate the expression/maintenance of increased synaptic strength and resultant persisting antidepressant effects. Specifically, while the initiating mechanisms of these therapies may differ (e.g., cell type-specificity, N-methyl-D-aspartate receptor (NMDAR) subtype-selective inhibition vs activation, metabotropic glutamate receptor 2/3 antagonism, AMPA receptor potentiation, 5-HT receptor-activating psychedelics, etc.), the sustained therapeutic mechanisms of putative rapid-acting antidepressants will be mediated, in part, by metaplastic effects that converge on consistent molecular mediators to enhance excitatory neurotransmission and altered capacity for synaptic plasticity. We conclude that the convergence of these therapeutic mechanisms provides the opportunity for metaplasticity processes to be harnessed as a druggable plasticity mechanism by next-generation therapeutics. Further, targeting metaplastic mechanisms presents therapeutic advantages including decreased dosing frequency and associated diminished adverse responses by eliminating the requirement for the drug to be continuously present.


Assuntos
Antidepressivos , Ketamina , Plasticidade Neuronal , Humanos , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Plasticidade Neuronal/efeitos dos fármacos , Ketamina/farmacologia , Ketamina/uso terapêutico , Animais , Depressão/tratamento farmacológico , Potenciação de Longa Duração/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapses/efeitos dos fármacos , Sinapses/metabolismo
5.
Immunity ; 45(2): 389-401, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27521269

RESUMO

CD8(+) T cells recognizing tumor-specific antigens are detected in cancer patients but are dysfunctional. Here we developed a tamoxifen-inducible liver cancer mouse model with a defined oncogenic driver antigen (SV40 large T-antigen) to follow the activation and differentiation of naive tumor-specific CD8(+) T (TST) cells after tumor initiation. Early during the pre-malignant phase of tumorigenesis, TST cells became dysfunctional, exhibiting phenotypic, functional, and transcriptional features similar to dysfunctional T cells isolated from late-stage human tumors. Thus, T cell dysfunction seen in advanced human cancers may already be established early during tumorigenesis. Although the TST cell dysfunctional state was initially therapeutically reversible, it ultimately evolved into a fixed state. Persistent antigen exposure rather than factors associated with the tumor microenvironment drove dysfunction. Moreover, the TST cell differentiation and dysfunction program exhibited features distinct from T cell exhaustion in chronic infections. Strategies to overcome this antigen-driven, cell-intrinsic dysfunction may be required to improve cancer immunotherapy.


Assuntos
Antígenos Transformantes de Poliomavirus/imunologia , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/imunologia , Imunoterapia Adotiva/métodos , Neoplasias Hepáticas/imunologia , Animais , Carcinogênese , Diferenciação Celular , Células Cultivadas , Senescência Celular , Modelos Animais de Doenças , Humanos , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/terapia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Tamoxifeno , Microambiente Tumoral
6.
J Immunol ; 211(9): 1426-1437, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37712758

RESUMO

Allogeneic hematopoietic stem cell transplantation (alloSCT) is, in many clinical settings, the only curative treatment for acute myeloid leukemia (AML). The clinical benefit of alloSCT greatly relies on the graft-versus-leukemia (GVL) effect. However, AML relapse remains the top cause of posttransplant death; this highlights the urgent need to enhance GVL. Studies of human GVL have been hindered by the lack of optimal clinically relevant models. In this article, we report, the successful establishment of a novel (to our knowledge) humanized GVL model system by transplanting clinically paired donor PBMCs and patient AML into MHC class I/II knockout NSG mice. We observed significantly reduced leukemia growth in humanized mice compared with mice that received AML alone, demonstrating a functional GVL effect. Using this model system, we studied human GVL responses against human AML cells in vivo and discovered that AML induced T cell depletion, likely because of increased T cell apoptosis. In addition, AML caused T cell exhaustion manifested by upregulation of inhibitory receptors, increased expression of exhaustion-related transcription factors, and decreased T cell function. Importantly, combined blockade of human T cell-inhibitory pathways effectively reduced leukemia burden and reinvigorated CD8 T cell function in this model system. These data, generated in a highly clinically relevant humanized GVL model, not only demonstrate AML-induced inhibition of alloreactive T cells but also identify promising therapeutic strategies targeting T cell depletion and exhaustion for overcoming GVL failure and treating AML relapse after alloSCT.

7.
J Infect Dis ; 230(1): e189-e198, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39052729

RESUMO

BACKGROUND: Streptococcus pneumoniae serotype 3 remains a problem globally. Malawi introduced 13-valent pneumococcal conjugate vaccine (PCV13) in 2011, but there has been no direct protection against serotype 3 carriage. We explored whether vaccine escape by serotype 3 is due to clonal expansion of a lineage with a competitive advantage. METHODS: The distribution of serotype 3 Global Pneumococcal Sequence Clusters (GPSCs) and sequence types (STs) globally was assessed using sequences from the Global Pneumococcal Sequencing Project. Whole-genome sequences of 135 serotype 3 carriage isolates from Blantyre, Malawi (2015-2019) were analyzed. Comparative analysis of the capsule locus, entire genomes, antimicrobial resistance, and phylogenetic reconstructions were undertaken. Opsonophagocytosis was evaluated using serum samples from vaccinated adults and children. RESULTS: Serotype 3 GPSC10-ST700 isolates were most prominent in Malawi. Compared with the prototypical serotype 3 capsular polysaccharide locus sequence, 6 genes are absent, with retention of capsule polysaccharide biosynthesis. This lineage is characterized by increased antimicrobial resistance and lower susceptibility to opsonophagocytic killing. CONCLUSIONS: A serotype 3 variant in Malawi has genotypic and phenotypic characteristics that could enhance vaccine escape and clonal expansion after post-PCV13 introduction. Genomic surveillance among high-burden populations is essential to improve the effectiveness of next-generation pneumococcal vaccines.


Assuntos
Cápsulas Bacterianas , Filogenia , Infecções Pneumocócicas , Vacinas Pneumocócicas , Sorogrupo , Streptococcus pneumoniae , Humanos , Vacinas Pneumocócicas/imunologia , Vacinas Pneumocócicas/administração & dosagem , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/imunologia , Streptococcus pneumoniae/classificação , Infecções Pneumocócicas/prevenção & controle , Infecções Pneumocócicas/microbiologia , Infecções Pneumocócicas/imunologia , Cápsulas Bacterianas/imunologia , Cápsulas Bacterianas/genética , Malaui , Adulto , Sequenciamento Completo do Genoma , Pré-Escolar , Criança , Vacinas Conjugadas/imunologia , Masculino , Genoma Bacteriano , Feminino , Adulto Jovem , Lactente , Genótipo , Portador Sadio/microbiologia
8.
J Neurosci ; 43(6): 1038-1050, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36596696

RESUMO

Ketamine is a well-characterized NMDA receptor (NMDAR) antagonist, although the relevance of this pharmacology to its rapid (within hours of administration) antidepressant actions, which depend on mechanisms convergent with strengthening of excitatory synapses, is unclear. Activation of synaptic NMDARs is necessary for the induction of canonical long-term potentiation (LTP) leading to a sustained expression of increased synaptic strength. We tested the hypothesis that induction of rapid antidepressant effects requires NMDAR activation, by using behavioral pharmacology, western blot quantification of hippocampal synaptoneurosomal protein levels, and ex vivo hippocampal slice electrophysiology in male mice. We found that ketamine exerts an inverted U-shaped dose-response in antidepressant-sensitive behavioral tests, suggesting that an excessive NMDAR inhibition can prevent ketamine's antidepressant effects. Ketamine's actions to induce antidepressant-like behavioral effects, up-regulation of hippocampal AMPAR subunits GluA1 and GluA2, as well as metaplasticity measured ex vivo using electrically-stimulated LTP, were abolished by pretreatment with other non-antidepressant NMDAR antagonists, including MK-801 and CPP. Similarly, the antidepressant-like actions of other putative rapid-acting antidepressant drugs (2R,6R)-hydroxynorketamine (ketamine metabolite), MRK-016 (GABAAα5 negative allosteric modulator), and LY341495 (mGlu2/3 receptor antagonist) were blocked by NMDAR inhibition. Ketamine acted synergistically with an NMDAR positive allosteric modulator to exert antidepressant-like behavioral effects and activation of the NMDAR subunit GluN2A was necessary and sufficient for such relevant effects. We conclude rapid-acting antidepressant compounds share a common downstream NMDAR-activation dependent effector mechanism, despite variation in initial pharmacological targets. Promoting NMDAR signaling or other approaches that enhance NMDAR-dependent LTP-like synaptic potentiation may be an effective antidepressant strategy.SIGNIFICANCE STATEMENT The anesthetic and antidepressant drug ketamine is well-characterized as an NMDA receptor (NMDAR) antagonist; though, the relevance and full impact of this pharmacology to its antidepressant actions is unclear. We found that NMDAR activation, which occurs downstream of their initial actions, is necessary for the beneficial effects of ketamine and several other putative antidepressant compounds. As such, promoting NMDAR signaling, or other approaches that enhance NMDAR-dependent long-term potentiation (LTP)-like synaptic potentiation in vivo may be an effective antidepressant strategy directly, or acting synergistically with other drug or interventional treatments.


Assuntos
Ketamina , Masculino , Camundongos , Animais , Ketamina/farmacologia , N-Metilaspartato , Receptores de N-Metil-D-Aspartato/metabolismo , Depressão/tratamento farmacológico , Antidepressivos/farmacologia
9.
J Am Chem Soc ; 146(23): 16184-16193, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38814893

RESUMO

Coupling molecules to a quantized radiation field inside an optical cavity has shown great promise to modify chemical reactivity. In this work, we show that the ground-state selectivity of the electrophilic bromination of nitrobenzene can be fundamentally changed by strongly coupling the reaction to the cavity, generating ortho- or para-substituted products instead of the meta product. Importantly, these are products that are not obtained from the same reaction outside the cavity. A recently developed ab initio approach was used to theoretically compute the relative energies of the cationic Wheland intermediates, which indicate the kinetically preferred bromination site for all products. Performing an analysis of the ground-state electron density for the Wheland intermediates inside and outside the cavity, we demonstrate how strong coupling induces reorganization of the molecular charge distribution, which in turn leads to different bromination sites directly dependent on the cavity conditions. Overall, the results presented here can be used to understand cavity induced changes to ground-state chemical reactivity from a mechanistic perspective as well as to directly connect frontier theoretical simulations to state-of-the-art, but realistic, experimental cavity conditions.

10.
J Neurophysiol ; 131(1): 64-74, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38050689

RESUMO

(2R,6R)-Hydroxynorketamine (HNK) is a ketamine metabolite that shows rapid antidepressant-like effects in preclinical studies and lacks the adverse N-methyl-d-aspartate receptor (NMDAR) inhibition-related properties of ketamine. Investigating how (2R,6R)-HNK exerts its antidepressant actions may be informative in the design of novel pharmacotherapies with improved safety and efficacy. We sought to identify the molecular substrates through which (2R,6R)-HNK induces functional changes at excitatory synapses, a prevailing hypothesis for how rapid antidepressant effects are initiated. We recorded excitatory postsynaptic potentials in hippocampal slices from male Wistar Kyoto rats, which have impaired hippocampal plasticity and are resistant to traditional antidepressants. (2R,6R)-HNK (10 µM) led to a rapid potentiation of electrically evoked excitatory postsynaptic potentials at Schaffer collateral CA1 stratum radiatum synapses. This potentiation was associated with a decrease in paired pulse facilitation, suggesting an increase in the probability of glutamate release. The (2R,6R)-HNK-induced potentiation was blocked by inhibiting either cyclic adenosine monophosphate (cAMP) or its downstream target, cAMP-dependent protein kinase (PKA). As cAMP is a potent regulator of brain-derived neurotrophic factor (BDNF) release, we assessed whether (2R,6R)-HNK exerts this acute potentiation through a rapid increase in cAMP-dependent BDNF-TrkB signaling. We found that the cAMP-PKA-dependent potentiation was not dependent on TrkB activation by BDNF, which functionally delimits the acute synaptic effects of (2R,6R)-HNK from its sustained BDNF-dependent actions in vivo. These results suggest that, by potentiating glutamate release via cAMP-PKA signaling, (2R,6R)-HNK initiates acute adaptations in fast excitatory synaptic transmission that promote structural plasticity leading to maintained antidepressant action.NEW & NOTEWORTHY Ketamine is a rapid-acting antidepressant and its preclinical effects are mimicked by its (2R,6R)-(HNK) metabolite. We found that (2R,6R)-HNK initiates acute adaptations in fast excitatory synaptic transmission by potentiating glutamate release via cAMP-PKA signaling at hippocampal Schaffer collateral synapses. This cAMP-PKA-dependent potentiation was not dependent on TrkB activation by BDNF, which functionally delimits the rapid synaptic effects of (2R,6R)-HNK from its sustained BDNF-dependent actions that are thought to maintain antidepressant action in vivo.


Assuntos
Ketamina , Ratos , Animais , Masculino , Ketamina/farmacologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Antidepressivos/metabolismo , Antidepressivos/farmacologia , Hipocampo/metabolismo , Ácido Glutâmico/metabolismo
11.
Nat Mater ; 22(12): 1453-1462, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37620646

RESUMO

Robots have components that work together to accomplish a task. Colloids are particles, usually less than 100 µm, that are small enough that they do not settle out of solution. Colloidal robots are particles capable of functions such as sensing, computation, communication, locomotion and energy management that are all controlled by the particle itself. Their design and synthesis is an emerging area of interdisciplinary research drawing from materials science, colloid science, self-assembly, robophysics and control theory. Many colloidal robot systems approach synthetic versions of biological cells in autonomy and may find ultimate utility in bringing these specialized functions to previously inaccessible locations. This Perspective examines the emerging literature and highlights certain design principles and strategies towards the realization of colloidal robots.

12.
Ann Surg Oncol ; 31(3): 1447-1454, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37907701

RESUMO

BACKGROUND: Colorectal cancer (CRC) is the second leading cause of cancer-related mortality in the United States (US); however, there are limited data on location of death in patients who die from CRC. We examined the trends in location of death and determinants in patients dying from CRC in the US. METHODS: We utilized the Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research database to extract nationwide data on underlying cause of death as CRC. A multinomial logistic regression was performed to assess associations between clinico-sociodemographic characteristics and location of death. RESULTS: There were 850,750 deaths due to CRC from 2003 to 2019. There was a gradual decrease in deaths in hospital, nursing home, or outpatient facility/emergency department over time and an increase in deaths at home and in hospice. Relative to White decedents, Black, Asian, and American Indian/Alaska Native decedents were less likely to die at home and in hospice compared with hospitals. Individuals with lower educational status also had a lower risk of dying at home or in hospice compared with in hospitals. CONCLUSIONS: The gradual shift in location of death of patients who die of CRC from institutionalized settings to home and hospice is a promising trend and reflects the prioritization of patient goals for end-of-life care by healthcare providers. However, there are existing sociodemographic disparities in access to deaths at home and in hospice, which emphasizes the need for policy interventions to reduce health inequity in end-of-life care for CRC.


Assuntos
Neoplasias Colorretais , Cuidados Paliativos na Terminalidade da Vida , Hospitais para Doentes Terminais , Assistência Terminal , Humanos , Estados Unidos , Casas de Saúde
13.
Cephalalgia ; 44(6): 3331024241259452, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38870368

RESUMO

BACKGROUND: There is no defined preventive treatment protocol for persistent post-craniotomy headache. In several small case series and individual case reports onabotulinumtoxinA injected into the craniotomy scar has shown possible efficacy. What is lacking is long term follow-up and if focusing on the cranial suture lines along with the craniotomy scar can enhance improvement and provide more sustained benefit. METHODS: Retrospective chart review with case series. RESULTS: Four patients (three women, one man) with ICHD-3 defined persistent post craniotomy headache were treated using a novel onabotulinumtoxinA injection protocol. All the patients presented with continuous head pain of moderate to severe intensity. All had severe allodynia on the side of their craniotomy. All had significant reduction in quality of life. Our application of onabotulinumtoxinA involved injection into both the surgical scar and the transected/irritated cranial suture lines noted on neuroimaging and physical examination. With treatment all patients demonstrated significant benefit including a reduction in daily pain intensity (75%-100%), developing periods of pain freedom (2-7 days per week) and having a dramatic improvement in quality of life (close to 100% in all). The benefit was sustained for at least five years of follow-up. CONCLUSION: From our case series it appears that injection not only along the painful craniotomy scar but into the involved cranial suture lines provides positive efficacy and sustained improvement in patients with persistent post craniotomy headache.


Assuntos
Toxinas Botulínicas Tipo A , Cicatriz , Craniotomia , Humanos , Feminino , Craniotomia/efeitos adversos , Toxinas Botulínicas Tipo A/administração & dosagem , Toxinas Botulínicas Tipo A/uso terapêutico , Masculino , Pessoa de Meia-Idade , Adulto , Estudos Retrospectivos , Seguimentos , Suturas Cranianas/cirurgia , Resultado do Tratamento
14.
Pharmacol Res ; 203: 107163, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38569982

RESUMO

Current cancer therapy can be effective, but the development of drug resistant disease is the usual outcome. These drugs can eliminate most of the tumor burden but often fail to eliminate the rare, "Drug Tolerant Persister" (DTP) cell subpopulations in residual tumors, which can be referred to as "Persister" cells. Therefore, novel therapeutic agents specifically targeting or preventing the development of drug-resistant tumors mediated by the remaining persister cells subpopulations are needed. Since approximately ninety percent of cancer-related deaths occur because of the eventual development of drug resistance, identifying, and dissecting the biology of the persister cells is essential for the creation of drugs to target them. While there remains uncertainty surrounding all the markers identifying DTP cells in the literature, this review summarizes the drugs and therapeutic approaches that are available to target the persister cell subpopulations expressing the cellular markers ATP-binding cassette sub-family B member 5 (ABCB5), CD133, CD271, Lysine-specific histone demethylase 5 (KDM5), and aldehyde dehydrogenase (ALDH). Persister cells expressing these markers were selected as the focus of this review because they have been found on cells surviving following drug treatments that promote recurrent drug resistant cancer and are associated with stem cell-like properties, including self-renewal, differentiation, and resistance to therapy. The limitations and obstacles facing the development of agents targeting these DTP cell subpopulations are detailed, with discussion of potential solutions and current research areas needing further exploration.


Assuntos
Antineoplásicos , Resistencia a Medicamentos Antineoplásicos , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Animais , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Tolerância a Medicamentos , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genética
15.
J Surg Res ; 295: 268-273, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38048750

RESUMO

INTRODUCTION: Whether neoadjuvant chemoradiation for locally advanced rectal cancer (LARC) induces secondary cancers is controversial. This retrospective cohort study describes the incidence of secondary cancers in LARC patients. METHODS: We compared 364 LARC patients who received conventional (50.4 Gy) or short course neoadjuvant radiation (25 Gy x 5 fractions) followed by resection to 142 patients with surgically resected rectal cancer who did not receive radiation at a single institution from 2004 to 2018. Secondary cancer was defined as any nonmetastatic noncolorectal malignancy diagnosed via biopsy or definitive imaging criteria at least 6 mo after completion of neoadjuvant therapy or after resection in the comparison group. RESULTS: Among the neoadjuvant radiation group (364 patients, 40% female, age 61 ± 13 y), 32 patients developed 34 (9.3%) secondary cancers. Three cases involved a pelvic organ. Among the comparison group (142 patients, 39% female, age 64 ± 15 y), 15 patients (10.6%) developed a secondary cancer. Five cases involved pelvic organs. Secondary cancer incidence did not differ between groups. Latency period to secondary cancer diagnosis was 6.7 ± 4.3 y. Patients who received radiation underwent longer median follow-up (6.8 versus 4.5 y, P < 0.01) and were significantly less likely to develop a pelvic organ cancer (odds ratio 0.18; 95% confidence interval, 0.04-0.83; P = 0.02). No genetic mutations or cancer syndromes were identified among patients with secondary cancers. CONCLUSIONS: Neoadjuvant chemoradiation is not associated with increased secondary cancer risk in LARC patients and may have a local protective effect on pelvic organs, especially prostate. Ongoing follow-up is critical to continue risk assessment.


Assuntos
Terapia Neoadjuvante , Neoplasias Retais , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Terapia Neoadjuvante/efeitos adversos , Terapia Neoadjuvante/métodos , Incidência , Estudos Retrospectivos , Quimiorradioterapia/efeitos adversos , Quimiorradioterapia/métodos , Neoplasias Retais/terapia , Neoplasias Retais/tratamento farmacológico , Estadiamento de Neoplasias , Resultado do Tratamento
16.
Future Oncol ; 20(19): 1333-1349, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38597742

RESUMO

Aim: Cost-effectiveness analysis (CEA) was performed to compare axicabtagene ciloleucel (axi-cel) with tisagenlecleucel (tisa-cel) and lisocabtagene (liso-cel) for treatment of relapsed or refractory large B-cell lymphoma in adult patients after ≥2 lines of therapy in Japan. Materials & methods: Cost-effectiveness analysis was conducted using the partition survival mixture cure model based on the ZUMA-1 trial and adjusted to the JULIET and TRANSCEND trials using matching-adjusted indirect comparisons. Results & conclusion: Axi-cel was associated with greater incremental life years (3.13 and 2.85) and incremental quality-adjusted life-years (2.65 and 2.24), thus generated lower incremental direct medical costs (-$976.29 [-¥137,657] and -$242.00 [-¥34,122]), compared with tisa-cel and liso-cel. Axi-cel was cost-effective option compared with tisa-cel and liso-cel from a Japanese payer's perspective.


[Box: see text].


Assuntos
Análise Custo-Benefício , Anos de Vida Ajustados por Qualidade de Vida , Humanos , Japão/epidemiologia , Masculino , Feminino , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/economia , Linfoma Difuso de Grandes Células B/mortalidade , Antígenos CD19/economia , Antígenos CD19/imunologia , Antígenos CD19/uso terapêutico , Receptores de Antígenos de Linfócitos T/uso terapêutico , Imunoterapia Adotiva/economia , Imunoterapia Adotiva/métodos , Pessoa de Meia-Idade , Adulto , Vacinas Anticâncer/economia , Vacinas Anticâncer/administração & dosagem , Idoso , Produtos Biológicos/economia , Produtos Biológicos/uso terapêutico , Análise de Custo-Efetividade
17.
J Chem Phys ; 161(1)2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38953450

RESUMO

The generation of exciton-polaritons through strong light-matter interactions represents an emerging platform for exploring quantum phenomena. A significant challenge in colloidal nanocrystal-based polaritonic systems is the ability to operate at room temperature with high fidelity. Here, we demonstrate the generation of room-temperature exciton-polaritons through the coupling of CdSe nanoplatelets (NPLs) with a Fabry-Pérot optical cavity, leading to a Rabi splitting of 74.6 meV. Quantum-classical calculations accurately predict the complex dynamics between the many dark state excitons and the optically allowed polariton states, including the experimentally observed lower polariton photoluminescence emission, and the concentration of photoluminescence intensities at higher in-plane momenta as the cavity becomes more negatively detuned. The Rabi splitting measured at 5 K is similar to that at 300 K, validating the feasibility of the temperature-independent operation of this polaritonic system. Overall, these results show that CdSe NPLs are an excellent material to facilitate the development of room-temperature quantum technologies.

18.
J Pers ; 92(2): 530-547, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37208805

RESUMO

INTRODUCTION: Humanistic psychologists have conceptualized a tendency among humans to experience continual open-ended psychological growth. This study aims to measure the rate at which one grows psychologically using a novel growth curve modeling approach that addresses previous limitations. We also examine the effects of nine potential contributors to growth identified from the literature. METHOD: Throughout the freshman year, 556 college students responded six times. Increments of growth were added up to create cumulative growth, which was then fit to a growth curve model to produce an estimate of the growth rate. The growth rate was then regressed on the Time 1 predictors to examine their unique effects. RESULTS: Models fit well. Five predictors significantly predicted the growth rate after controlling for the average of other predictors. When all predictors were entered simultaneously, three predictors (hope, meaning, and personal growth initiative) showed significant unique effects. The growth rate predicted well-being and satisfaction at Time 6. CONCLUSION: We successfully measured the rate of psychological growth and examined its antecedents. Follow-up analyses suggested that the predictors not showing unique effects may indirectly predict growth rates via the proximal role of the three significant predictors, an idea that awaits future corroboration using within-individual designs.


Assuntos
Desenvolvimento Psicológico , Estudantes , Humanos , Estudos Longitudinais
19.
Proc Natl Acad Sci U S A ; 118(27)2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34210794

RESUMO

As it becomes possible to simulate increasingly complex neural networks, it becomes correspondingly important to model the sensory information that animals actively acquire: the biomechanics of sensory acquisition directly determines the sensory input and therefore neural processing. Here, we exploit the tractable mechanics of the well-studied rodent vibrissal ("whisker") system to present a model that can simulate the signals acquired by a full sensor array actively sampling the environment. Rodents actively "whisk" ∼60 vibrissae (whiskers) to obtain tactile information, and this system is therefore ideal to study closed-loop sensorimotor processing. The simulation framework presented here, WHISKiT Physics, incorporates realistic morphology of the rat whisker array to predict the time-varying mechanical signals generated at each whisker base during sensory acquisition. Single-whisker dynamics were optimized based on experimental data and then validated against free tip oscillations and dynamic responses to collisions. The model is then extrapolated to include all whiskers in the array, incorporating each whisker's individual geometry. Simulation examples in laboratory and natural environments demonstrate that WHISKiT Physics can predict input signals during various behaviors, currently impossible in the biological animal. In one exemplary use of the model, the results suggest that active whisking increases in-plane whisker bending compared to passive stimulation and that principal component analysis can reveal the relative contributions of whisker identity and mechanics at each whisker base to the vibrissotactile response. These results highlight how interactions between array morphology and individual whisker geometry and dynamics shape the signals that the brain must process.


Assuntos
Comportamento Animal/fisiologia , Modelos Neurológicos , Tato/fisiologia , Animais , Estimulação Física , Ratos , Transdução de Sinais , Fatores de Tempo , Vibrissas/fisiologia
20.
Aging Ment Health ; : 1-6, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38533723

RESUMO

OBJECTIVES: This study sought to (1) identify the percentage of high-risk substance use or substance use disorder (SUD) and (2) examine the factors associated with high-risk substance use or SUD in adults aged 50 years and older receiving mental health treatment with a primary delirium or dementia diagnosis. METHOD: This study used 7 years (2013-2019) of national administrative data on community mental health center patients aged 50 years and older with a primary delirium or dementia diagnosis receiving treatment in the United States (U.S.). To examine factors associated with the dependent variable (high-risk substance use or SUD), a multivariable binary logistic regression model was utilized. RESULTS: The sample included 77,509 individuals who were mostly aged 65 years and older (69.7%), and did not have co-occurring high-risk substance use or SUD (90.1%). Receiving treatment in a U.S. region other than the Northeast, being younger, male, not non-Hispanic White, and having multiple mental health diagnoses had greater odds of co-occurring high-risk substance use or SUD. CONCLUSION: One in ten persons in this sample having high-risk substance use or SUD highlights the clinical necessity for screening and subsequent treatment for co-occurring high-risk substance use among persons receiving treatment for a neurocognitive disorder.

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