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1.
Nanomaterials (Basel) ; 13(22)2023 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-37999327

RESUMO

Zeolites and zeolitic imidazolate frameworks (ZIFs) are crystalline aluminosilicates with porous structure, which are closely linked with nanomaterials. They are characterized by enhanced ion exchange capacity, physical-chemical stability, thermal stability and biocompatibility, making them a promising material for dental applications. This review aimed to provide an overview of the application of zeolites and ZIFs in dentistry. The common zeolite compounds for dental application include silver zeolite, zinc zeolite, calcium zeolite and strontium zeolite. The common ZIFs for dental application include ZIF-8 and ZIF-67. Zeolites and ZIFs have been employed in various areas of dentistry, such as restorative dentistry, endodontics, prosthodontics, implantology, periodontics, orthodontics and oral surgery. In restorative dentistry, zeolites and ZIFs are used as antimicrobial additives in dental adhesives and restorative materials. In endodontics, zeolites are used in root-end fillings, root canal irritants, root canal sealers and bone matrix scaffolds for peri-apical diseases. In prosthodontics, zeolites can be incorporated into denture bases, tissue conditioners, soft denture liners and dental prostheses. In implantology, zeolites and ZIFs are applied in dental implants, bone graft materials, bone adhesive hydrogels, drug delivery systems and electrospinning. In periodontics, zeolites can be applied as antibacterial agents for deep periodontal pockets, while ZIFs can be embedded in guided tissue regeneration membranes and guided bone regeneration membranes. In orthodontics, zeolites can be applied in orthodontic appliances. Additionally, for oral surgery, zeolites can be used in oral cancer diagnostic marker membranes, maxillofacial prosthesis silicone elastomer and tooth extraction medicines, while ZIFs can be incorporated to osteogenic glue or used as a carrier for antitumour drugs. In summary, zeolites have a broad application in dentistry and are receiving more attention from clinicians and researchers.

2.
J Biol Chem ; 299(11): 105350, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37832874

RESUMO

Wnt signaling plays a key role in the mature CNS by regulating trafficking of NMDA-type glutamate receptors and intrinsic properties of neurons. The Wnt receptor ROR2 has been identified as a necessary component of the neuronal Wnt5a/Ca2+ signaling pathway that regulates synaptic and neuronal function. Since ROR2 is considered a pseudokinase, its mechanism for downstream signaling upon ligand binding has been controversial. It has been suggested that its role is to function as a coreceptor of a G-protein-coupled Wnt receptor of the Frizzled family. We show that chemically induced homodimerization of ROR2 is sufficient to recapitulate key signaling events downstream of receptor activation in neurons, including PKC and JNK kinases activation, elevation of somatic and dendritic Ca2+ levels, and increased trafficking of NMDARs to synapses. In addition, we show that homodimerization of ROR2 induces phosphorylation of the receptor on Tyr residues. Point mutations in the conserved but presumed nonfunctional ATP-binding site of the receptor prevent its phosphorylation, as well as downstream signaling. This suggests an active kinase domain. Our results indicate that ROR2 can signal independently of Frizzled receptors to regulate the trafficking of a key synaptic component. Additionally, they suggest that homodimerization can overcome structural conformations that render the tyrosine kinase inactive. A better understanding of ROR2 signaling is crucial for comprehending the regulation of synaptic and neuronal function in normal brain processes in mature animals.


Assuntos
Receptores Órfãos Semelhantes a Receptor Tirosina Quinase , Via de Sinalização Wnt , Animais , Cálcio/metabolismo , Sinalização do Cálcio , Receptores Frizzled/genética , Receptores Frizzled/metabolismo , Neurônios/metabolismo , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/genética , Receptores Acoplados a Proteínas G/metabolismo , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Proteína Wnt-5a/metabolismo , Dimerização
3.
Br J Anaesth ; 130(5): 567-572, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36868965

RESUMO

BACKGROUND: Postoperative cognitive dysfunction (POCD) is a concern after anaesthesia and surgery, but preoperative discussion of neurocognitive risks with older patients rarely occurs. Anecdotal experiences of POCD are common in the popular media and may inform patient perspectives. However, the degree of alignment between lay and scientific perspectives on POCD is not known. METHODS: We performed inductive qualitative thematic analysis on website user comments publicly submitted under an article entitled, 'The hidden long-term risks of surgery: "It gives people's brains a hard time"', published by the UK-based news source The Guardian in April 2022. RESULTS: We analysed 84 comments from 67 unique users. Themes that emerged from user comments included the importance of functional impact ('Couldn't work … even reading was a struggle'), attribution to a range of causes but particularly the use of general, rather than consciousness-preserving, anaesthesia techniques ('side effects aren't fully understood'), and inadequate preparation and response by healthcare providers ('I would have benefited by being warned'). CONCLUSIONS: There is misalignment between professional and lay understandings of POCD. Lay people emphasise subjective and functional impact of symptoms, and express beliefs about the role of anaesthetics in causing POCD. Some patients and caregivers affected by POCD report feeling abandoned by medical providers. In 2018, new nomenclature for postoperative neurocognitive disorders was published, which better aligns with lay perspectives by including subjective complaints and functional decline. Further studies based on newer definitions and public messaging may improve concordance between different understandings of this postoperative syndrome.


Assuntos
Anestesia , Anestésicos , Complicações Cognitivas Pós-Operatórias , Humanos , Complicações Cognitivas Pós-Operatórias/etiologia , Complicações Pós-Operatórias/diagnóstico , Encéfalo , Anestesia/efeitos adversos
4.
Cell Rep ; 42(3): 112170, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36842085

RESUMO

Sensory neurons in the neocortex exhibit distinct functional selectivity to constitute the neural map. While neocortical map of the visual cortex in higher mammals is clustered, it displays a striking "salt-and-pepper" pattern in rodents. However, little is known about the origin and basis of the interspersed neocortical map. Here we report that the intricate excitatory neuronal kinship-dependent synaptic connectivity influences precise functional map organization in the mouse primary visual cortex. While sister neurons originating from the same neurogenic radial glial progenitors (RGPs) preferentially develop synapses, cousin neurons derived from amplifying RGPs selectively antagonize horizontal synapse formation. Accordantly, cousin neurons in similar layers exhibit clear functional selectivity differences, contributing to a salt-and-pepper architecture. Removal of clustered protocadherins (cPCDHs), the largest subgroup of the diverse cadherin superfamily, eliminates functional selectivity differences between cousin neurons and alters neocortical map organization. These results suggest that developmental neuronal origin regulates neocortical map formation via cPCDHs.


Assuntos
Neocórtex , Camundongos , Animais , Neocórtex/fisiologia , Protocaderinas , Neurônios/fisiologia , Sinapses , Células Ependimogliais , Mamíferos
5.
Front Bioeng Biotechnol ; 10: 959335, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36329705

RESUMO

Integration of mechanical cues in conventional 2D or 3D cell culture platforms is an important consideration for in vivo and ex vivo models of lung health and disease. Available commercial and published custom-made devices are frequently limited in breadth of applications, scalability, and customization. Herein we present a technical report on an open-source, cell and tissue (CaT) stretcher, with modularity for different in vitro and ex vivo systems, that includes the following features: 1) Programmability for modeling different breathing patterns, 2) scalability to support low to high-throughput experimentation, and 3) modularity for submerged cell culture, organ-on-chips, hydrogels, and live tissues. The strategy for connecting the experimental cell or tissue samples to the stretching device were designed to ensure that traditional biomedical outcome measurements including, but not limited to microscopy, soluble mediator measurement, and gene and protein expression remained possible. Lastly, to increase the uptake of the device within the community, the system was built with economically feasible and available components. To accommodate diverse in vitro and ex vivo model systems we developed a variety of chips made of compliant polydimethylsiloxane (PDMS) and optimized coating strategies to increase cell adherence and viability during stretch. The CaT stretcher was validated for studying mechanotransduction pathways in lung cells and tissues, with an increase in alpha smooth muscle actin protein following stretch for 24 h observed in independent submerged monolayer, 3D hydrogel, and live lung tissue experiments. We anticipate that the open-source CaT stretcher design will increase accessibility to studies of the dynamic lung microenvironment through direct implementation by other research groups or custom iterations on our designs.

6.
Front Med (Lausanne) ; 9: 1071348, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36714130

RESUMO

Genomic medicine, an emerging medical discipline, applies the principles of evolution, developmental biology, functional genomics, and structural genomics within clinical care. Enabling widespread adoption and integration of genomic medicine into clinical practice is key to achieving precision medicine. We delineate a biological framework defining diagnostic utility of genomic testing and map the process of genomic medicine to inform integration into clinical practice. This process leverages collaboration and collective cognition of patients, principal care providers, clinical genomic specialists, laboratory geneticists, and payers. We detail considerations for referral, triage, patient intake, phenotyping, testing eligibility, variant analysis and interpretation, counseling, and management within the utilitarian limitations of health care systems. To reduce barriers for clinician engagement in genomic medicine, we provide several decision-making frameworks and tools and describe the implementation of the proposed workflow in a prototyped electronic platform that facilitates genomic care. Finally, we discuss a vision for the future of genomic medicine and comment on areas for continued efforts.

7.
Mov Disord ; 36(6): 1332-1341, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33847406

RESUMO

BACKGROUND: Abnormal oscillatory neural activity in the beta-frequency band (13-35 Hz) is thought to play a role in Parkinson's disease (PD); however, increasing evidence points to alterations in high-frequency ranges (>100 Hz) also having pathophysiological relevance. OBJECTIVES: Studies have found that power in subthalamic nucleus (STN) high-frequency oscillations is increased with dopaminergic medication and during voluntary movements, implicating these brain rhythms in normal basal ganglia function. The objective of this study was to investigate whether similar signaling occurs in the internal globus pallidus (GPi), a nucleus increasingly used as a target for deep brain stimulation (DBS) for PD. METHODS: Spontaneous and movement-related GPi field potentials were recorded from DBS leads in 5 externalized PD patients on and off dopaminergic medication, as well as from 3 rhesus monkeys before and after the induction of parkinsonism with the neurotoxin 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine. RESULTS: In the parkinsonian condition, we identified a prominent oscillatory peak centered at 200-300 Hz that increased during movement. In patients the magnitude of high-frequency oscillation modulation was negatively correlated with bradykinesia. In monkeys, high-frequency oscillations were mostly absent in the naive condition but emerged after the neurotoxin 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine. In patients, spontaneous high-frequency oscillations were significantly attenuated on-medication. CONCLUSIONS: Our findings provide evidence in support of the hypothesis that exaggerated, movement-modulated high-frequency oscillations in the GPi are pathophysiological features of PD. These findings suggest that the functional role(s) of high-frequency oscillations may differ between the STN and GPi and motivate additional investigations into their relationship to motor control in normal and diseased states.


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson , Núcleo Subtalâmico , Biomarcadores , Globo Pálido , Humanos , Doença de Parkinson/terapia
8.
Sci Rep ; 11(1): 231, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420199

RESUMO

Alcohol use disorder exhausts substantial social and economic costs, with recent dramatic increases in female problem drinking. Thus, it is critically important to understand signaling differences underlying alcohol consumption across the sexes. Orexin-1 receptors (Ox1Rs) can strongly promote motivated behavior, and we previously identified Ox1Rs within nucleus accumbens shell (shell) as crucial for driving binge intake in higher-drinking male mice. Here, shell Ox1R inhibition did not alter female mouse alcohol drinking, unlike in males. Also, lower dose systemic Ox1R inhibition reduced compulsion-like alcohol intake in both sexes, indicating that female Ox1Rs can drive some aspects of pathological consumption, and higher doses of systemic Ox1R inhibition (which might have more off-target effects) reduced binge drinking in both sexes. In contrast to shell Ox1Rs, inhibiting shell calcium-permeable AMPA receptors (CP-AMPARs) strongly reduced alcohol drinking in both sexes, which was specific to alcohol since this did not reduce saccharin intake in either sex. Our results together suggest that the shell critically regulates binge drinking in both sexes, with shell CP-AMPARs supporting intake in both sexes, while shell Ox1Rs drove drinking only in males. Our findings provide important new information about sex-specific and -general mechanisms that promote binge alcohol intake and possible targeted therapeutic interventions.


Assuntos
Consumo Excessivo de Bebidas Alcoólicas/metabolismo , Núcleo Accumbens/metabolismo , Receptores de Orexina/metabolismo , Receptores de AMPA/metabolismo , Animais , Feminino , Masculino , Camundongos , Caracteres Sexuais
9.
Eur Heart J Cardiovasc Imaging ; 19(3): 339-346, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28387860

RESUMO

Aims: Prolonged central circulation transit time (TT) has long been associated with heart failure (HF) and left ventricular (LV) dysfunction. In this study, we assessed the central circulation TT using cardiovascular magnetic resonance imaging (CMR) in patients with HF of preserved ejection fraction (HFpEF) and of reduced EF (HFrEF) and investigated its relation to haemodynamics. Methods and results: Fifty eight prospectively recruited volunteers underwent CMR. TT was taken as the time between the peaks of time-intensity curves from first pass perfusion images and normalized to cardiac cycle length intervals. Left ventricular ejection fraction was 55 ± 3%, 57 ± 7%, and 28 ± 10% in control (N = 10), HFpEF (N = 20), and HFrEF (N = 28), respectively (P < 0.001). Global central TT from right atrium to ascending aorta was significantly prolonged in patients with HFrEF [17 ± 5 cardiac cycles (cc)] and HFpEF (12 ± 3 cc) when compared to the normal controls (8 ± 1 cc) (P < 0.001). Regional TT was also prolonged in HF patients between right atrium and pulmonary artery (PA), PA and left atrium (LA), and LA and ascending aorta (all P-value < 0.001) with the longest delay seen between PA and LA. Among 48 HF patients, 28 underwent same day cardiac catheterization. Multivariate regression analysis suggested while reduced left and right ventricular EF were the strongest correlates for HFrEF increased pulmonary capillary wedge (PCWP) and reduced PA oxygen saturation were the strongest correlates for HFpEF. Conclusions: Global and regional central TT can be assessed in the first pass perfusion imaging. Prolonged normalized global TT correlates with reduced EF in HFrEF and increased PCWP in HFpEF.


Assuntos
Baixo Débito Cardíaco/diagnóstico por imagem , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Imagem Cinética por Ressonância Magnética/métodos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Adulto , Idoso , Velocidade do Fluxo Sanguíneo/fisiologia , Baixo Débito Cardíaco/fisiopatologia , Estudos de Coortes , Intervalos de Confiança , Feminino , Hemodinâmica/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Estudos Prospectivos , Análise de Onda de Pulso , Medição de Risco , Volume Sistólico/fisiologia
10.
Minn Med ; 97(5): 47-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24941596

RESUMO

There is little data on the long-term health outcomes of patients with neurological conditions treated at long-term acute care specialty hospitals. In order to learn more about these patients and the most effective way to care for them, Bethesda Hospital in St. Paul created a neuroscience research registry. The registry's target population is patients with complex neurological conditions such as aneurysm or intracranial bleed, stroke, seizures, delirium and confusion and traumatic brain injury. This article describes the development of the registry, which has enrolled 857 patients thus far, and what is being learned about those patients.


Assuntos
Pesquisa Biomédica , Encefalopatias/terapia , Neurociências , Sistema de Registros , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Minnesota , Prognóstico , Adulto Jovem
11.
J Cardiovasc Magn Reson ; 15: 99, 2013 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-24168103

RESUMO

BACKGROUND: Left atrial volume (LAV) and emptying fraction (LAEF) are phasic during cardiac cycle. Their relationships to left ventricular end diastolic pressure (LVEDP) have not been fully defined. METHODS: Forty one patients undergoing clinically indicated left heart catheterization were recruited for same day cardiovascular magnetic resonance (CMR). LAV and LAEF were assessed in cine images using biplane area and length method. Three phasic LAV was assessed at LV end systole (LAV(max)), LV end diastole (LAV(min)) and late LV diastole prior to LA contraction (LAV(ac)). LAEF was assessed as global LAEF (LAEF(Total)), passive (LAEF(Passive)) and active LAEF (LAEF(Contractile)). The relationships of phasic LAV and LAEF to LVEDP were assessed using Receiver operating characteristic comparing areas under the curves (AUC). RESULTS: The mean age of the patients was 59 years. A history of heart failure was present in 16 (39%) with NYHA functional class III or IV in 8 (20%) patients. Average LV ejection fraction was 49 ± 16% ranging from 10% to 74% and LVEDP by catheterization 14 ± 8 mmHg ranging from 4 mmHg to 32 mmHg. LAV(min) had the strongest association with LVEDP elevation (>12 mmHg) (AUC 0.765, p = 0.002), as compared to LAV(max) (AUC 0.677, p = 0.074) and LAV(ac) (AUC 0.735, p = 0.008). Among three phasic LAEF assessed, LAEF(Total) had the closest association with LVEDP elevation (AUC 0.780, p = 0.001), followed by LAEF(Contractile) (AUC 0.698, p = 0.022) and LAEF(Passive) (AUC 0.656, p = 0.077). CONCLUSIONS: Increased LAV(min) and decreased LAEF(Total) have the best performance in identifying elevated LVEDP among three phasic LAV and LAEF analyzed. Future studies should further characterize LA phasic indices in clinical outcomes.


Assuntos
Função do Átrio Esquerdo , Cardiopatias/diagnóstico , Imagem Cinética por Ressonância Magnética , Função Ventricular Esquerda , Pressão Ventricular , Adulto , Idoso , Área Sob a Curva , Cateterismo Cardíaco , Feminino , Cardiopatias/fisiopatologia , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Volume Sistólico , Fatores de Tempo
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