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1.
Cell ; 182(5): 1125-1139.e18, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32822574

RESUMO

Maternal decidual NK (dNK) cells promote placentation, but how they protect against placental infection while maintaining fetal tolerance is unclear. Here we show that human dNK cells highly express the antimicrobial peptide granulysin (GNLY) and selectively transfer it via nanotubes to extravillous trophoblasts to kill intracellular Listeria monocytogenes (Lm) without killing the trophoblast. Transfer of GNLY, but not other cell death-inducing cytotoxic granule proteins, strongly inhibits Lm in human placental cultures and in mouse and human trophoblast cell lines. Placental and fetal Lm loads are lower and pregnancy success is greatly improved in pregnant Lm-infected GNLY-transgenic mice than in wild-type mice that lack GNLY. This immune defense is not restricted to pregnancy; peripheral NK (pNK) cells also transfer GNLY to kill bacteria in macrophages and dendritic cells without killing the host cell. Nanotube transfer of GNLY allows dNK to protect against infection while leaving the maternal-fetal barrier intact.


Assuntos
Antígenos de Diferenciação de Linfócitos T/imunologia , Bactérias/imunologia , Movimento Celular/imunologia , Células Matadoras Naturais/imunologia , Trofoblastos/imunologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Feminino , Células HeLa , Humanos , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Placenta/imunologia , Placenta/microbiologia , Gravidez , Ratos , Células THP-1 , Trofoblastos/microbiologia
2.
Annu Rev Neurosci ; 45: 223-247, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35259917

RESUMO

Breathing is a vital rhythmic motor behavior with a surprisingly broad influence on the brain and body. The apparent simplicity of breathing belies a complex neural control system, the breathing central pattern generator (bCPG), that exhibits diverse operational modes to regulate gas exchange and coordinate breathing with an array of behaviors. In this review, we focus on selected advances in our understanding of the bCPG. At the core of the bCPG is the preBötzinger complex (preBötC), which drives inspiratory rhythm via an unexpectedly sophisticated emergent mechanism. Synchronization dynamics underlying preBötC rhythmogenesis imbue the system with robustness and lability. These dynamics are modulated by inputs from throughout the brain and generate rhythmic, patterned activity that is widely distributed. The connectivity and an emerging literature support a link between breathing, emotion, and cognition that is becoming experimentally tractable. These advances bring great potential for elucidating function and dysfunction in breathing and other mammalian neural circuits.


Assuntos
Respiração , Centro Respiratório , Animais , Encéfalo , Emoções , Mamíferos , Centro Respiratório/fisiologia
3.
Proc Natl Acad Sci U S A ; 121(35): e2401134121, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39163335

RESUMO

In recent years, self-assembly has emerged as a powerful tool for fabricating functional materials. Since self-assembly is fundamentally determined by the particle interactions in the system, if we can gain full control over these interactions, it would open the door for creating functional materials by design. In this paper, we exploit capillary interactions between colloidal particles at liquid interfaces to create two-dimensional (2D) materials where particle interactions and self-assembly can be fully programmed using particle shape alone. Specifically, we consider colloidal particles which are polygonal plates with homogeneous surface chemistry and undulating edges as this particle geometry gives us precise and independent control over both short-range hard-core repulsions and longer-range capillary interactions. To illustrate the immense potential provided by our system for programming self-assembly, we use minimum energy calculations and Monte Carlo simulations to show that polygonal plates with different in-plane shapes (hexagons, truncated triangles, triangles, squares) and edge undulations of different multipolar order (hexapolar, octopolar, dodecapolar) can be used to create a rich variety of 2D structures, including hexagonal close-packed, honeycomb, Kagome, and quasicrystal lattices. Since the required particle shapes can be readily fabricated experimentally, we can use our colloidal system to control the entire process chain for materials design, from initial design and fabrication of the building blocks, to final assembly of the emergent 2D material.

4.
Proc Natl Acad Sci U S A ; 121(31): e2404229121, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39052836

RESUMO

The distinct human leukocyte antigen (HLA) class I expression pattern of human extravillous trophoblasts (EVT) endows them with unique tolerogenic properties that enable successful pregnancy. Nevertheless, how this process is elaborately regulated remains elusive. Previously, E74 like ETS transcription factor 3 (ELF3) was identified to govern high-level HLA-C expression in EVT. In the present study, ELF3 is found to bind to the enhancer region of two adjacent NOD-like receptor (NLR) genes, NLR family pyrin domain-containing 2 and 7 (NLRP2, NLRP7). Notably, our analysis of ELF3-deficient JEG-3 cells, a human choriocarcinoma cell line widely used to study EVT biology, suggests that ELF3 transactivates NLRP7 while suppressing the expression of NLRP2. Moreover, we find that NLRP2 and NLRP7 have opposing effects on HLA-C expression, thus implicating them in immune evasion at the maternal-fetal interface. We confirmed that NLRP2 suppresses HLA-C levels and described a unique role for NLRP7 in promoting HLA-C expression in JEG-3. These results suggest that these two NLR genes, which arose via gene duplication in primates, are fine-tuned by ELF3 yet have acquired divergent functions to enable proper expression levels of HLA-C in EVT, presumably through modulating the degradation kinetics of IkBα. Targeting the ELF3-NLRP2/NLRP7-HLA-C axis may hold therapeutic potential for managing pregnancy-related disorders, such as recurrent hydatidiform moles and fetal growth restriction, and thus improve placental development and pregnancy outcomes.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas Reguladoras de Apoptose , Trofoblastos Extravilosos , Antígenos HLA-C , Trofoblastos , Feminino , Humanos , Gravidez , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Linhagem Celular Tumoral , Regulação da Expressão Gênica , Antígenos HLA-C/metabolismo , Antígenos HLA-C/genética , Proteínas Proto-Oncogênicas c-ets/metabolismo , Proteínas Proto-Oncogênicas c-ets/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Trofoblastos/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo
5.
Proc Natl Acad Sci U S A ; 121(41): e2408315121, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39361645

RESUMO

The peptidoglycan pathway represents one of the most successful antibacterial targets with the last critical step being the flipping of carrier lipid, undecaprenyl phosphate (C55-P), across the membrane to reenter the pathway. This translocation of C55-P is facilitated by DedA and DUF368 domain-containing family membrane proteins via unknown mechanisms. Here, we employ native mass spectrometry to investigate the interactions of UptA, a member of the DedA family of membrane protein from Bacillus subtilis, with C55-P, membrane phospholipids, and cell wall-targeting antibiotics. Our results show that UptA, expressed and purified in Escherichia coli, forms monomer-dimer equilibria, and binds to C55-P in a pH-dependent fashion. Specifically, we show that UptA interacts more favorably with C55-P over shorter-chain analogs and membrane phospholipids. Moreover, we demonstrate that lipopeptide antibiotics, amphomycin and aspartocin D, can directly inhibit UptA function by out-competing the substrate for the protein binding, in addition to their propensity to form complex with free C55-P. Overall, this study shows that UptA-mediated translocation of C55-P is potentially mediated by pH and anionic phospholipids and provides insights for future development of antibiotics targeting carrier lipid recycling.


Assuntos
Antibacterianos , Bacillus subtilis , Proteínas de Bactérias , Fosfatos de Poli-Isoprenil , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/metabolismo , Antibacterianos/farmacologia , Antibacterianos/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Fosfatos de Poli-Isoprenil/metabolismo , Lipopeptídeos/farmacologia , Lipopeptídeos/metabolismo , Proteínas de Membrana/metabolismo , Ligação Proteica , Escherichia coli/metabolismo , Escherichia coli/efeitos dos fármacos
6.
J Biol Chem ; 300(9): 107644, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39122012

RESUMO

Cdc14 phosphatases are related structurally and mechanistically to protein tyrosine phosphatases (PTPs) but evolved a unique specificity for phosphoSer-Pro-X-Lys/Arg sites primarily deposited by cyclin-dependent kinases. This specialization is widely conserved in eukaryotes. The evolutionary reconfiguration of the Cdc14 active site to selectively accommodate phosphoSer-Pro likely required modification to the canonical PTP catalytic cycle. While studying Saccharomyces cerevisiae Cdc14, we discovered a short sequence in the disordered C terminus, distal to the catalytic domain, which mimics an optimal substrate. Kinetic analyses demonstrated this pseudosubstrate binds the active site and strongly stimulates rate-limiting phosphoenzyme hydrolysis, and we named it "substrate-like catalytic enhancer" (SLiCE). The SLiCE motif is found in all Dikarya fungal Cdc14 orthologs and contains an invariant glutamine, which we propose is positioned via substrate-like contacts to assist orientation of the hydrolytic water, similar to a conserved active site glutamine in other PTPs that Cdc14 lacks. AlphaFold2 predictions revealed vertebrate Cdc14 orthologs contain a conserved C-terminal alpha helix bound to the active site. Although apparently unrelated to the fungal sequence, this motif also makes substrate-like contacts and has an invariant glutamine in the catalytic pocket. Altering these residues in human Cdc14A and Cdc14B demonstrated that it functions by the same mechanism as the fungal motif. However, the fungal and vertebrate SLiCE motifs were not functionally interchangeable, illuminating potential active site differences during catalysis. Finally, we show that the fungal SLiCE motif is a target for phosphoregulation of Cdc14 activity. Our study uncovered evolution of an unusual stimulatory pseudosubstrate motif in Cdc14 phosphatases.


Assuntos
Motivos de Aminoácidos , Domínio Catalítico , Proteínas Tirosina Fosfatases , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/enzimologia , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Tirosina Fosfatases/química , Proteínas Tirosina Fosfatases/genética , Humanos , Especificidade por Substrato , Catálise , Sequência de Aminoácidos , Cinética , Proteínas de Ciclo Celular
7.
J Cell Sci ; 136(14)2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37334742

RESUMO

Cisplatin is an effective platinum-based chemotherapeutic with several side effects, including ototoxicity. Cochlear cells have low rates of proliferation yet are highly susceptible to cisplatin. We hypothesised that cisplatin ototoxicity might be caused by cisplatin-protein interactions rather than cisplatin-DNA interactions. Two known cisplatin-binding proteins are involved in the stress granule (SG) response. SGs are a pro-survival mechanism involving formation of transient ribonucleoprotein complexes during stress. We examined the effects of cisplatin on SG dynamics and composition in cell lines derived from the cochlea and retinal pigment epithelium. Cisplatin-induced SGs are significantly diminished in size and quantity compared to arsenite-induced SGs and are persistent after 24 h recovery. Additionally, cisplatin pre-treated cells were unable to form a typical SG response to subsequent arsenite stress. Cisplatin-induced SGs had significant reductions in the sequestration of eIF4G and the proteins RACK1 and DDX3X. Live-cell imaging of Texas Red-conjugated cisplatin revealed its localisation to SGs and retention for at least 24 h. We show cisplatin-induced SGs have impaired assembly, altered composition and are persistent, providing evidence of an alternate mechanism for cisplatin-induced ototoxicity via an impaired SG response.


Assuntos
Arsenitos , Ototoxicidade , Humanos , Cisplatino/farmacologia , Arsenitos/toxicidade , Arsenitos/metabolismo , Ototoxicidade/metabolismo , Grânulos de Estresse , Grânulos Citoplasmáticos/metabolismo
8.
Brain ; 147(5): 1856-1870, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38146224

RESUMO

Alterations in the extracellular matrix are common in patients with epilepsy and animal models of epilepsy, yet whether they are the cause or consequence of seizures and epilepsy development is unknown. Using Theiler's murine encephalomyelitis virus (TMEV) infection-induced model of acquired epilepsy, we found de novo expression of chondroitin sulfate proteoglycans (CSPGs), a major extracellular matrix component, in dentate gyrus (DG) and amygdala exclusively in mice with acute seizures. Preventing the synthesis of CSPGs specifically in DG and amygdala by deletion of the major CSPG aggrecan reduced seizure burden. Patch-clamp recordings from dentate granule cells revealed enhanced intrinsic and synaptic excitability in seizing mice that was significantly ameliorated by aggrecan deletion. In situ experiments suggested that dentate granule cell hyperexcitability results from negatively charged CSPGs increasing stationary cations on the membrane, thereby depolarizing neurons, increasing their intrinsic and synaptic excitability. These results show increased expression of CSPGs in the DG and amygdala as one of the causal factors for TMEV-induced acute seizures. We also show identical changes in CSPGs in pilocarpine-induced epilepsy, suggesting that enhanced CSPGs in the DG and amygdala may be a common ictogenic factor and potential therapeutic target.


Assuntos
Tonsila do Cerebelo , Proteoglicanas de Sulfatos de Condroitina , Giro Denteado , Convulsões , Animais , Giro Denteado/metabolismo , Tonsila do Cerebelo/metabolismo , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Camundongos , Convulsões/metabolismo , Masculino , Theilovirus , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Camundongos Knockout , Agrecanas/metabolismo , Neurônios/metabolismo
9.
J Neurosci ; 43(2): 240-260, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36400528

RESUMO

The preBötzinger Complex (preBötC) encodes inspiratory time as rhythmic bursts of activity underlying each breath. Spike synchronization throughout a sparsely connected preBötC microcircuit initiates bursts that ultimately drive the inspiratory motor patterns. Using minimal microcircuit models to explore burst initiation dynamics, we examined the variability in probability and latency to burst following exogenous stimulation of a small subset of neurons, mimicking experiments. Among various physiologically plausible graphs of 1000 excitatory neurons constructed using experimentally determined synaptic and connectivity parameters, directed Erdos-Rényi graphs with a broad (lognormal) distribution of synaptic weights best captured the experimentally observed dynamics. preBötC synchronization leading to bursts was regulated by the efferent connectivity of spiking neurons that are optimally tuned to amplify modest preinspiratory activity through input convergence. Using graph-theoretic and machine learning-based analyses, we found that input convergence of efferent connectivity at the next-nearest neighbor order was a strong predictor of incipient synchronization. Our analyses revealed a crucial role of synaptic heterogeneity in imparting exceptionally robust yet flexible preBötC attractor dynamics. Given the pervasiveness of lognormally distributed synaptic strengths throughout the nervous system, we postulate that these mechanisms represent a ubiquitous template for temporal processing and decision-making computational motifs.SIGNIFICANCE STATEMENT Mammalian breathing is robust, virtually continuous throughout life, yet is inherently labile: to adapt to rapid metabolic shifts (e.g., fleeing a predator or chasing prey); for airway reflexes; and to enable nonventilatory behaviors (e.g., vocalization, breathholding, laughing). Canonical theoretical frameworks-based on pacemakers and intrinsic bursting-cannot account for the observed robustness and flexibility of the preBötzinger Complex rhythm. Experiments reveal that network synchronization is the key to initiate inspiratory bursts in each breathing cycle. We investigated preBötC synchronization dynamics using network models constructed with experimentally determined neuronal and synaptic parameters. We discovered that a fat-tailed (non-Gaussian) synaptic weight distribution-a manifestation of synaptic heterogeneity-augments neuronal synchronization and attractor dynamics in this vital rhythmogenic network, contributing to its extraordinary reliability and responsiveness.


Assuntos
Neurônios , Centro Respiratório , Animais , Centro Respiratório/fisiologia , Reprodutibilidade dos Testes , Neurônios/fisiologia , Respiração , Mamíferos
10.
J Neurosci ; 43(17): 3144-3158, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-36973013

RESUMO

The meaning of words in natural language depends crucially on context. However, most neuroimaging studies of word meaning use isolated words and isolated sentences with little context. Because the brain may process natural language differently from how it processes simplified stimuli, there is a pressing need to determine whether prior results on word meaning generalize to natural language. fMRI was used to record human brain activity while four subjects (two female) read words in four conditions that vary in context: narratives, isolated sentences, blocks of semantically similar words, and isolated words. We then compared the signal-to-noise ratio (SNR) of evoked brain responses, and we used a voxelwise encoding modeling approach to compare the representation of semantic information across the four conditions. We find four consistent effects of varying context. First, stimuli with more context evoke brain responses with higher SNR across bilateral visual, temporal, parietal, and prefrontal cortices compared with stimuli with little context. Second, increasing context increases the representation of semantic information across bilateral temporal, parietal, and prefrontal cortices at the group level. In individual subjects, only natural language stimuli consistently evoke widespread representation of semantic information. Third, context affects voxel semantic tuning. Finally, models estimated using stimuli with little context do not generalize well to natural language. These results show that context has large effects on the quality of neuroimaging data and on the representation of meaning in the brain. Thus, neuroimaging studies that use stimuli with little context may not generalize well to the natural regime.SIGNIFICANCE STATEMENT Context is an important part of understanding the meaning of natural language, but most neuroimaging studies of meaning use isolated words and isolated sentences with little context. Here, we examined whether the results of neuroimaging studies that use out-of-context stimuli generalize to natural language. We find that increasing context improves the quality of neuro-imaging data and changes where and how semantic information is represented in the brain. These results suggest that findings from studies using out-of-context stimuli may not generalize to natural language used in daily life.


Assuntos
Compreensão , Semântica , Humanos , Feminino , Compreensão/fisiologia , Encéfalo/fisiologia , Idioma , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos
11.
J Am Chem Soc ; 146(4): 2345-2350, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38241031

RESUMO

Archangiumide is the first known macrolide natural product comprising an endocyclic allene. For the ring strain that this linear substructure might entail, it was planned to unveil the allene at a very late stage of the projected total synthesis; in actual fact, this was achieved as the last step of the longest linear sequence by using an otherwise globally deprotected substrate. This unconventional timing was made possible by a gold catalyzed rearrangement of a macrocyclic propargyl benzyl ether derivative that uses a -PMB group as latent hydride source to unveil the signature cycloallene; the protecting group therefore gains a strategic role beyond its mere safeguarding function. Although the gold catalyzed reaction per se is stereoablative, the macrocyclic frame of the target was found to impose high selectivity and a stereoconvergent character on the transformation. The required substrate was formed by ring closing alkyne metathesis (RCAM) with the aid of a new air-stable molybdenum alkylidyne catalyst.

12.
N Engl J Med ; 384(19): 1789-1799, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33979487

RESUMO

BACKGROUND: Official recommendations differ regarding tympanostomy-tube placement for children with recurrent acute otitis media. METHODS: We randomly assigned children 6 to 35 months of age who had had at least three episodes of acute otitis media within 6 months, or at least four episodes within 12 months with at least one episode within the preceding 6 months, to either undergo tympanostomy-tube placement or receive medical management involving episodic antimicrobial treatment. The primary outcome was the mean number of episodes of acute otitis media per child-year (rate) during a 2-year period. RESULTS: In our main, intention-to-treat analysis, the rate (±SE) of episodes of acute otitis media per child-year during a 2-year period was 1.48±0.08 in the tympanostomy-tube group and 1.56±0.08 in the medical-management group (P = 0.66). Because 10% of the children in the tympanostomy-tube group did not undergo tympanostomy-tube placement and 16% of the children in the medical-management group underwent tympanostomy-tube placement at parental request, we conducted a per-protocol analysis, which gave corresponding episode rates of 1.47±0.08 and 1.72±0.11, respectively. Among secondary outcomes in the main analysis, results were mixed. Favoring tympanostomy-tube placement were the time to a first episode of acute otitis media, various episode-related clinical findings, and the percentage of children meeting specified criteria for treatment failure. Favoring medical management was children's cumulative number of days with otorrhea. Outcomes that did not show substantial differences included the frequency distribution of episodes of acute otitis media, the percentage of episodes considered to be severe, and antimicrobial resistance among respiratory isolates. Trial-related adverse events were limited to those included among the secondary outcomes of the trial. CONCLUSIONS: Among children 6 to 35 months of age with recurrent acute otitis media, the rate of episodes of acute otitis media during a 2-year period was not significantly lower with tympanostomy-tube placement than with medical management. (Funded by the National Institute on Deafness and Other Communication Disorders and others; ClinicalTrials.gov number, NCT02567825.).


Assuntos
Antibacterianos/uso terapêutico , Ventilação da Orelha Média , Otite Média/tratamento farmacológico , Otite Média/cirurgia , Doença Aguda , Antibacterianos/efeitos adversos , Pré-Escolar , Farmacorresistência Bacteriana , Feminino , Humanos , Lactente , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Masculino , Otite Média com Derrame , Qualidade de Vida , Recidiva
13.
J Vasc Surg ; 79(2): 305-315.e3, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37913944

RESUMO

OBJECTIVE: Carotid artery stenting (CAS) for heavily calcified lesions is controversial due to concern for stent failure and increased perioperative stroke risk. However, the degree to which calcification affects outcomes is poorly understood, particularly in transcarotid artery revascularization (TCAR). With the precipitous increase in TCAR use and its expansion to standard surgical-risk patients, we aimed to determine the impact of lesion calcification on CAS outcomes to ensure its safe and appropriate use. METHODS: We identified patients in the Vascular Quality Initiative who underwent first-time transfemoral CAS (tfCAS) and TCAR between 2016 and 2021. Patients were stratified into groups based on degree of lesion calcification: no calcification, 1% to 50% calcification, 51% to 99% calcification, and 100% circumferential calcification or intraluminal protrusion. Outcomes included in-hospital and 1-year composite stroke/death, as well as individual stroke, death, and myocardial infarction outcomes. Logistic regression was used to evaluate associations between degree of calcification and these outcomes. RESULTS: Among 21,860 patients undergoing CAS, 28% patients had no calcification, 34% had 1% to 50% calcification, 35% had 51% to 99% calcification, and 3% had 100% circumferential calcification/protrusion. Patients with 51% to 99% and circumferential calcification/protrusion had higher odds of in-hospital stroke/death (odds ratio [OR], 1.3; 95% confidence interval [CI], 1.02-1.6; P = .034; OR, 1.9; 95% CI, 1.1-2.9; P = .004, respectively) compared with those with no calcification. Circumferential calcification was also associated with increased risk for in-hospital myocardial infarction (OR, 3.5; 95% CI, 1.5-8.0; P = .003). In tfCAS patients, only circumferential calcification/protrusion was associated with higher in-hospital stroke/death odds (OR, 2.0; 95% CI, 1.2-3.4; P = .013), whereas for TCAR patients, 51% to 99% calcification was associated with increased odds of in-hospital stroke/death (OR, 1.5; 95% CI, 1.1-2.2; P = .025). At 1 year, circumferential calcification/protrusion was associated with higher odds of ipsilateral stroke/death (12.4% vs 6.6%; hazard ratio, 1.64; P = .002). CONCLUSIONS: Among patients undergoing CAS, there is an increased risk of in-hospital stroke/death for lesions with >50% calcification or circumferential/protruding plaques. Increasing severity of carotid lesion calcification is a significant risk factor for stroke/death in patients undergoing CAS, regardless of approach.


Assuntos
Estenose das Carótidas , Procedimentos Endovasculares , Infarto do Miocárdio , Acidente Vascular Cerebral , Humanos , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/terapia , Procedimentos Endovasculares/efeitos adversos , Medição de Risco , Stents/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Estudos Retrospectivos , Acidente Vascular Cerebral/etiologia , Fatores de Risco , Infarto do Miocárdio/etiologia , Artéria Femoral , Artérias Carótidas
14.
J Vasc Surg ; 79(5): 1142-1150.e2, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38190927

RESUMO

OBJECTIVE: The aim of this study was to report the results of a prospective, single-arm, registry-based study assessing the safety and performance of a paclitaxel drug-coated balloon (DCB) for the treatment of superficial femoral artery (SFA) or popliteal artery in-stent restenosis (ISR) in a United States population. METHODS: We conducted a prospective, non-randomized, multi-center, single-arm, post-market registry of the IN.PACT Admiral DCB for the treatment of ISR lesions in the SFA or popliteal artery at 43 sites within the Society for Vascular Surgery (SVS) Vascular Quality Initiative (VQI) Registry from December 2016 to January 2020. Clinical outcomes were assessed at 12, 24, and 36 months. The primary endpoint was target lesion revascularization at 12 months. Secondary endpoints included technical success, target vessel revascularization, major limb amputation, and all-cause mortality. Results are presented as survival probabilities based on Kaplan-Meier survival estimates. RESULTS: Patients (N = 300) were 58% male, with a mean age of 68 ± 10 years. Diabetes was present in 56%, 80% presented with claudication, and 20% with rest pain. Lesions included ISR of the SFA in 68%, SFA-popliteal in 26%, and popliteal arteries in 7%. The mean lesion length was 17.8 ± 11.8 cm. Lesions were categorized as occlusions in 43% (mean occluded length, 16 ± 10 cm). TASC type was A (17%), B (29%), C (38%), and D (15%). Technical success was 99%. Re-stenting was performed in 5% and thrombolysis in 0.6% of patients. Kaplan-Meier estimates for freedom from target lesion revascularization were 90%, 72%, and 62% at 12, 24, and 36 months. Freedom from target vessel revascularization was 88%, 68%, and 59% and freedom from major target limb amputation was 99.6%, 98.9%, and 98.9%, respectively, at 12, 24, and 36 months. Survival was 95%, 89%, and 85% at 12, 24, and 36 months. CONCLUSIONS: This post-market registry-based study shows promising results in treating femoral-popliteal ISR with paclitaxel DCB in comparison to the results of plain balloon angioplasty reported in the literature. These results demonstrate the ability of the SVS VQI to conduct post-market evaluation of peripheral devices in partnership with industry and federal regulators.


Assuntos
Angioplastia com Balão , Reestenose Coronária , Doença Arterial Periférica , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Artéria Femoral/diagnóstico por imagem , Artéria Poplítea/diagnóstico por imagem , Paclitaxel/efeitos adversos , Estudos Prospectivos , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/terapia , Salvamento de Membro , Fatores de Tempo , Constrição Patológica , Sistema de Registros , Materiais Revestidos Biocompatíveis , Resultado do Tratamento
15.
J Vasc Surg ; 79(3): 695-703, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37939746

RESUMO

OBJECTIVE: The optimal management of patients with asymptomatic carotid stenosis (AsxCS) is enduringly controversial. We updated our 2021 Expert Review and Position Statement, focusing on recent advances in the diagnosis and management of patients with AsxCS. METHODS: A systematic review of the literature was performed up to August 1, 2023, using PubMed/PubMed Central, EMBASE and Scopus. The following keywords were used in various combinations: "asymptomatic carotid stenosis," "carotid endarterectomy" (CEA), "carotid artery stenting" (CAS), and "transcarotid artery revascularization" (TCAR). Areas covered included (i) improvements in best medical treatment (BMT) for patients with AsxCS and declining stroke risk, (ii) technological advances in surgical/endovascular skills/techniques and outcomes, (iii) risk factors, clinical/imaging characteristics and risk prediction models for the identification of high-risk AsxCS patient subgroups, and (iv) the association between cognitive dysfunction and AsxCS. RESULTS: BMT is essential for all patients with AsxCS, regardless of whether they will eventually be offered CEA, CAS, or TCAR. Specific patient subgroups at high risk for stroke despite BMT should be considered for a carotid revascularization procedure. These patients include those with severe (≥80%) AsxCS, transcranial Doppler-detected microemboli, plaque echolucency on Duplex ultrasound examination, silent infarcts on brain computed tomography or magnetic resonance angiography scans, decreased cerebrovascular reserve, increased size of juxtaluminal hypoechoic area, AsxCS progression, carotid plaque ulceration, and intraplaque hemorrhage. Treatment of patients with AsxCS should be individualized, taking into consideration individual patient preferences and needs, clinical and imaging characteristics, and cultural, ethnic, and social factors. Solid evidence supporting or refuting an association between AsxCS and cognitive dysfunction is lacking. CONCLUSIONS: The optimal management of patients with AsxCS should include BMT for all individuals and a prophylactic carotid revascularization procedure (CEA, CAS, or TCAR) for some asymptomatic patient subgroups, additionally taking into consideration individual patient needs and preference, clinical and imaging characteristics, social and cultural factors, and the available stroke risk prediction models. Future studies should investigate the association between AsxCS with cognitive function and the role of carotid revascularization procedures in the progression or reversal of cognitive dysfunction.


Assuntos
Estenose das Carótidas , Endarterectomia das Carótidas , Procedimentos Endovasculares , Acidente Vascular Cerebral , Humanos , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/cirurgia , Medição de Risco , Resultado do Tratamento , Endarterectomia das Carótidas/efeitos adversos , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Procedimentos Endovasculares/efeitos adversos , Stents/efeitos adversos , Estudos Retrospectivos
16.
Chem Res Toxicol ; 37(5): 757-770, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38625865

RESUMO

Per- and polyfluoroalkyl substances (PFAS) are known for their high environmental persistence and potential toxicity. The presence of PFAS has been reported in many dairy products. However, the mechanisms underlying the accumulation of PFAS in these products remain unclear. Here, we used native mass spectrometry and molecular dynamics simulations to probe the interactions between 19 PFAS of environmental concern and two isoforms of the major bovine whey protein ß-lactoglobulin (ß-LG). We observed that six of these PFAS bound to both protein isoforms with low- to mid-micromolar dissociation constants. Based on quantitative, competitive binding experiments with endogenous ligands, PFAS can bind orthosterically and preferentially to ß-LG's hydrophobic ligand-binding calyx. ß-Cyclodextrin can also suppress binding of PFAS to ß-LG owing to the ability of ß-cyclodextrin to directly sequester PFAS from solution. This research sheds light on PFAS-ß-LG binding, suggesting that such interactions could impact lipid-fatty acid transport in bovine mammary glands at high PFAS concentrations. Furthermore, our results highlight the potential use of ß-cyclodextrin in mitigating PFAS binding, providing insights toward the development of strategies to reduce PFAS accumulation in dairy products and other biological systems.


Assuntos
Fluorocarbonos , Lactoglobulinas , Leite , Animais , Lactoglobulinas/metabolismo , Lactoglobulinas/química , Bovinos , Leite/química , Leite/metabolismo , Fluorocarbonos/química , Fluorocarbonos/metabolismo , Simulação de Dinâmica Molecular , beta-Ciclodextrinas/química , beta-Ciclodextrinas/metabolismo , Sítios de Ligação , Ligação Proteica
17.
Br J Clin Pharmacol ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38529693

RESUMO

Pharmacovigilance is defined by the World Health Organization as "the science and activities relating to the detection, assessment, understanding and prevention of adverse effects or any other medicine/vaccine related problem". Pharmacovigilance studies are critical for detecting and assessing adverse events of medicines that may not have been observed in clinical trials. This activity is especially important in older people who are often excluded from clinical trials as they have multiple chronic conditions and use multiple medicines for longer durations than the clinical trials. In this narrative review we describe innovative methods in pharmacovigilance studies of medicines in older people that leverage the increasing availability of digital health technologies, electronic health records and real-world health data to identify and quantify medication related harms in older people.

18.
Chem Rev ; 122(8): 7327-7385, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-34449207

RESUMO

Small molecule drug discovery has been propelled by the continual development of novel scientific methodologies to occasion therapeutic advances. Although established biophysical methods can be used to obtain information regarding the molecular mechanisms underlying drug action, these approaches are often inefficient, low throughput, and ineffective in the analysis of heterogeneous systems including dynamic oligomeric assemblies and proteins that have undergone extensive post-translational modification. Native mass spectrometry can be used to probe protein-small molecule interactions with unprecedented speed and sensitivity, providing unique insights into polydisperse biomolecular systems that are commonly encountered during the drug discovery process. In this review, we describe potential and proven applications of native MS in the study of interactions between small, drug-like molecules and proteins, including large multiprotein complexes and membrane proteins. Approaches to quantify the thermodynamic and kinetic properties of ligand binding are discussed, alongside a summary of gas-phase ion activation techniques that have been used to interrogate the structure of protein-small molecule complexes. We additionally highlight some of the key areas in modern drug design for which native mass spectrometry has elicited significant advances. Future developments and applications of native mass spectrometry in drug discovery workflows are identified, including potential pathways toward studying protein-small molecule interactions on a whole-proteome scale.


Assuntos
Descoberta de Drogas , Proteoma , Descoberta de Drogas/métodos , Espectrometria de Massas/métodos , Proteínas de Membrana , Termodinâmica
19.
Artigo em Inglês | MEDLINE | ID: mdl-38981933

RESUMO

PURPOSE: The COVID-19 pandemic brought with it significant social, economic and health uncertainties. These were proposed to impact young people more compared to adults, leading adolescents to report more mental health problems during the pandemic. The current study examined whether differences in cognitive risk (tolerance of uncertainty) and protective (psychological flexibility) factors accounted for age-related differences in depression and anxiety. METHODS: These associations were investigated in the COVID-19 Risks Across the Lifespan (CORAL) cohort (N = 2280, 11-89 years). RESULTS: The results showed that adolescents experienced greater intolerance of uncertainty and lower psychological flexibility compared to adults and older adults. Tolerance of uncertainty did not account for age-related differences in depression or anxiety. However, psychological flexibility conferred more protective advantage for anxiety in adults compared to adolescents. CONCLUSION: The observed age-related differences in risk and protective factors advance our understanding of developmental vulnerabilities to depression and anxiety. Implications for mental health interventions in the context of future pandemics are discussed.

20.
Proc Natl Acad Sci U S A ; 118(47)2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34785597

RESUMO

Zika virus (ZIKV) during pregnancy infects fetal trophoblasts and causes placental damage and birth defects including microcephaly. Little is known about the anti-ZIKV cellular immune response at the maternal-fetal interface. Decidual natural killer cells (dNK), which directly contact fetal trophoblasts, are the dominant maternal immune cells in the first-trimester placenta, when ZIKV infection is most hazardous. Although dNK express all the cytolytic molecules needed to kill, they usually do not kill infected fetal cells but promote placentation. Here, we show that dNK degranulate and kill ZIKV-infected placental trophoblasts. ZIKV infection of trophoblasts causes endoplasmic reticulum (ER) stress, which makes them dNK targets by down-regulating HLA-C/G, natural killer (NK) inhibitory receptor ligands that help maintain tolerance of the semiallogeneic fetus. ER stress also activates the NK activating receptor NKp46. ZIKV infection of Ifnar1 -/- pregnant mice results in high viral titers and severe intrauterine growth restriction, which are exacerbated by depletion of NK or CD8 T cells, indicating that killer lymphocytes, on balance, protect the fetus from ZIKV by eliminating infected cells and reducing the spread of infection.


Assuntos
Células Matadoras Naturais/imunologia , Trofoblastos/imunologia , Infecção por Zika virus/imunologia , Zika virus/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Feminino , Feto/imunologia , Antígenos HLA-C , Tolerância Imunológica , Camundongos , Placenta/imunologia , Placentação , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Receptores KIR
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