Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 663
Filtrar
1.
Sci Rep ; 14(1): 11845, 2024 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-38782941

RESUMO

Tardigrades are renowned for their ability to survive a wide array of environmental stressors. In particular, tardigrades can curl in on themselves while losing a significant proportion of their internal water content to form a structure referred to as a tun. In surviving varying conditions, tardigrades undergo distinct morphological transformations that could indicate different mechanisms of stress sensing and tolerance specific to the stress condition. Methods to effectively distinguish between morphological transformations, including between tuns induced by different stress conditions, are lacking. Herein, an approach for discriminating between tardigrade morphological states is developed and utilized to compare sucrose- and CaCl2-induced tuns, using the model species Hypsibius exemplaris. A novel approach of shadow imaging with confocal laser scanning microscopy enabled production of three-dimensional renderings of Hys. exemplaris in various physiological states resulting in volume measurements. Combining these measurements with qualitative morphological analysis using scanning electron microscopy revealed that sucrose- and CaCl2-induced tuns have distinct morphologies, including differences in the amount of water expelled during tun formation. Further, varying the concentration of the applied stressor did not affect the amount of water lost, pointing towards water expulsion by Hys. exemplaris being a controlled process that is adapted to the specific stressors.


Assuntos
Cloreto de Cálcio , Sacarose , Animais , Cloreto de Cálcio/farmacologia , Microscopia Confocal/métodos , Estresse Fisiológico , Invertebrados , Microscopia Eletrônica de Varredura
2.
Adv Healthc Mater ; : e2303815, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38648653

RESUMO

RNA ligands of retinoic acid-inducible gene I (RIG-I) are a promising class of oligonucleotide therapeutics with broad potential as antiviral agents, vaccine adjuvants, and cancer immunotherapies. However, their translation has been limited by major drug delivery barriers, including poor cellular uptake, nuclease degradation, and an inability to access the cytosol where RIG-I is localized. Here this challenge is addressed by engineering nanoparticles that harness covalent conjugation of 5'-triphospate RNA (3pRNA) to endosome-destabilizing polymers. Compared to 3pRNA loaded into analogous nanoparticles via electrostatic interactions, it is found that covalent conjugation of 3pRNA improves loading efficiency, enhances immunostimulatory activity, protects against nuclease degradation, and improves serum stability. Additionally, it is found that 3pRNA could be conjugated via either a disulfide or thioether linkage, but that the latter is only permissible if conjugated distal to the 5'-triphosphate group. Finally, administration of 3pRNA-polymer conjugates to mice significantly increases type-I interferon levels relative to analogous carriers that use electrostatic 3pRNA loading. Collectively, these studies have yielded a next-generation polymeric carrier for in vivo delivery of 3pRNA, while also elucidating new chemical design principles for covalent conjugation of 3pRNA with potential to inform the further development of therapeutics and delivery technologies for pharmacological activation of RIG-I.

3.
Child Abuse Negl ; 152: 106752, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38555714

RESUMO

BACKGROUND: Narrative practice increases children's productivity in forensic interviews, and one recommended topic is the child's last birthday, though interviewers have raised concerns about its productivity. STUDY 1 OBJECTIVE: Study 1 surveyed forensic interviewers' use of and attitudes about the birthday narrative. PARTICIPANTS AND SETTING: Participants included 170 forensic interviewers who subscribed to a webinar promoting use of the birthday narrative (Mage = 43 years, SD = 10.2, 94 % female). RESULTS: Over half (55 %) of interviewers reported that they rarely/never asked about children's birthdays, and non-users were especially likely to view the birthday narrative as never/rarely productive. Although interviewers viewed memory difficulties as more likely to occur with the birthday narrative than other practice topics (the child's likes, the child's day), non-users did not view memory difficulties, reluctance, generic reports, or religious objections as especially problematic. Open-ended responses identified negative experiences with the birthday as an additional concern, and interviewers' recommended wording of the prompts suggested suboptimal questioning strategies. STUDY 2 OBJECTIVE: Study 2 assessed the use of the birthday narrative in forensic interviews. PARTICIPANTS AND SETTING: The sample included 350 forensic interviews with 4- to 12-year-old children (Mage = 8.85, SD = 2.59). RESULTS: Only 4 % of children failed to recall substantive information if interviewers persisted, though another 11 % failed when interviewers stopped persisting. Invitations were more effective than other question types, especially among older children. 21 % of children mentioned a negative detail during their narrative. CONCLUSIONS: Interviewers' skepticism about the birthday narrative may be due to suboptimal questioning and sensitivity to occasional failures and negative information.


Assuntos
Narração , Humanos , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Criança , Psiquiatria Legal/métodos , Entrevista Psicológica/métodos
4.
ACS Nano ; 18(9): 6845-6862, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38386282

RESUMO

Immune checkpoint blockade (ICB) has revolutionized cancer treatment and led to complete and durable responses, but only for a minority of patients. Resistance to ICB can largely be attributed to insufficient number and/or function of antitumor CD8+ T cells in the tumor microenvironment. Neoantigen targeted cancer vaccines can activate and expand the antitumor T cell repertoire, but historically, clinical responses have been poor because immunity against peptide antigens is typically weak, resulting in insufficient activation of CD8+ cytotoxic T cells. Herein, we describe a nanoparticle vaccine platform that can overcome these barriers in several ways. First, the vaccine can be reproducibly formulated using a scalable confined impingement jet mixing method to coload a variety of physicochemically diverse peptide antigens and multiple vaccine adjuvants into pH-responsive, vesicular nanoparticles that are monodisperse and less than 100 nm in diameter. Using this approach, we encapsulated synergistically acting adjuvants, cGAMP and monophosphoryl lipid A (MPLA), into the nanocarrier to induce a robust and tailored innate immune response that increased peptide antigen immunogenicity. We found that incorporating both adjuvants into the nanovaccine synergistically enhanced expression of dendritic cell costimulatory markers, pro-inflammatory cytokine secretion, and peptide antigen cross-presentation. Additionally, the nanoparticle delivery increased lymph node accumulation and uptake of peptide antigen by dendritic cells in the draining lymph node. Consequently, nanoparticle codelivery of peptide antigen, cGAMP, and MPLA enhanced the antigen-specific CD8+ T cell response and delayed tumor growth in several mouse models. Finally, the nanoparticle platform improved the efficacy of ICB immunotherapy in a murine colon carcinoma model. This work establishes a versatile nanoparticle vaccine platform for codelivery of peptide neoantigens and synergistic adjuvants to enhance responses to cancer vaccines.


Assuntos
Vacinas Anticâncer , Nanopartículas , Neoplasias , Humanos , Animais , Camundongos , Linfócitos T CD8-Positivos , Receptor 4 Toll-Like , Nanovacinas , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Antígenos , Peptídeos , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/uso terapêutico , Imunoterapia/métodos , Camundongos Endogâmicos C57BL , Microambiente Tumoral
5.
PLoS One ; 19(1): e0295062, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38232097

RESUMO

Tardigrades, commonly known as 'waterbears', are eight-legged microscopic invertebrates renowned for their ability to withstand extreme stressors, including high osmotic pressure, freezing temperatures, and complete desiccation. Limb retraction and substantial decreases to their internal water stores results in the tun state, greatly increasing their ability to survive. Emergence from the tun state and/or activity regain follows stress removal, where resumption of life cycle occurs as if stasis never occurred. However, the mechanism(s) through which tardigrades initiate tun formation is yet to be uncovered. Herein, we use chemobiosis to demonstrate that tardigrade tun formation is mediated by reactive oxygen species (ROS). We further reveal that tuns are dependent on reversible cysteine oxidation, and that this reversible cysteine oxidation is facilitated by the release of intracellular reactive oxygen species (ROS). We provide the first empirical evidence of chemobiosis and map the initiation and survival of tardigrades via osmobiosis, chemobiosis, and cryobiosis. In vivo electron paramagnetic spectrometry suggests an intracellular release of reactive oxygen species following stress induction; when this release is quenched through the application of exogenous antioxidants, the tardigrades can no longer survive osmotic stress. Together, this work suggests a conserved dependence of reversible cysteine oxidation across distinct tardigrade cryptobioses.


Assuntos
Cisteína , Tardígrados , Animais , Espécies Reativas de Oxigênio , Invertebrados , Congelamento
6.
Nature ; 621(7980): 716-722, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37758891

RESUMO

Einstein's general theory of relativity from 19151 remains the most successful description of gravitation. From the 1919 solar eclipse2 to the observation of gravitational waves3, the theory has passed many crucial experimental tests. However, the evolving concepts of dark matter and dark energy illustrate that there is much to be learned about the gravitating content of the universe. Singularities in the general theory of relativity and the lack of a quantum theory of gravity suggest that our picture is incomplete. It is thus prudent to explore gravity in exotic physical systems. Antimatter was unknown to Einstein in 1915. Dirac's theory4 appeared in 1928; the positron was observed5 in 1932. There has since been much speculation about gravity and antimatter. The theoretical consensus is that any laboratory mass must be attracted6 by the Earth, although some authors have considered the cosmological consequences if antimatter should be repelled by matter7-10. In the general theory of relativity, the weak equivalence principle (WEP) requires that all masses react identically to gravity, independent of their internal structure. Here we show that antihydrogen atoms, released from magnetic confinement in the ALPHA-g apparatus, behave in a way consistent with gravitational attraction to the Earth. Repulsive 'antigravity' is ruled out in this case. This experiment paves the way for precision studies of the magnitude of the gravitational acceleration between anti-atoms and the Earth to test the WEP.

7.
Nanoscale ; 15(39): 16016-16029, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37753868

RESUMO

The clinical translation of many biomolecular therapeutics has been hindered by undesirable pharmacokinetic (PK) properties, inadequate membrane permeability, poor endosomal escape and cytosolic delivery, and/or susceptibility to degradation. Overcoming these challenges merits the development of nanoscale drug carriers (nanocarriers) to improve the delivery of therapeutic cargo. Herein, we implement a flash nanoprecipitation (FNP) approach to produce nanocarriers of diverse vesicular morphologies by using various molecular weight PEG-bl-DEAEMA-co-BMA (PEG-DB) polymers. We demonstrated that FNP can produce uniform (PDI < 0.1) particles after 5 impingements, and that by varying the copolymer hydrophilic mass fraction, FNP enables access to a diverse variety of nanoarchitectures including micelles, unilamellar vesicles (polymersomes), and multi-compartment vesicles (MCVs). We synthesized a library of 2 kDa PEG block copolymers, with DEAEMA-co-BMA second block molecular weights of 3, 6, 12, 15, 20, and 30 kDa. All formulations were both pH responsive, endosomolytic, and capable of loading and cytosolically delivering small negatively charged molecules - albeit to different degrees. Using a B16.F10 melanoma model, we showcased the therapeutic potential of a lead FNP formulated PEG-DB nanocarrier, encapsulating the cyclic dinucleotide (CDN) cGAMP to activate the stimulator of interferon genes (STING) pathway in a therapeutically relevant context. Collectively, these data demonstrate that an FNP process can be used to formulate pH-responsive nanocarriers of diverse morphologies using a PEG-DB polymer system. As FNP is an industrially scalable process, these data address the critical translational challenge of producing PEG-DB nanoparticles at scale. Furthermore, the diverse morphologies produced may specialize in the delivery of distinct biomolecular cargos for other therapeutic applications, implicating the therapeutic potential of this platform in an array of disease applications.


Assuntos
Nanopartículas , Polímeros , Polímeros/química , Portadores de Fármacos/química , Nanopartículas/química , Micelas , Endossomos/metabolismo , Polietilenoglicóis/química
8.
Curr Opin Psychol ; 52: 101640, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37442080

RESUMO

Opposing theories posited that young adult substance use during the COVID-19 pandemic would decline due to restricted access and social engagement or increase due to efforts to cope with rising distress, loneliness, and isolation. Peer-reviewed global longitudinal studies found (a) overall declines in commonly used substances in 2020 with some rebounding in 2021; (b) individual differences in this pattern, with declines linked to factors limiting access and increases to pre-existing risk; and (c) under-developed evidence to evaluate increased coping-related use. Given potential links between surging mental health disorders and substance use, further surveillance and wider dissemination of substance use programming is needed, particularly for vulnerable individuals and settings.


Assuntos
COVID-19 , Transtornos Relacionados ao Uso de Substâncias , Humanos , Adulto Jovem , Pandemias , Adaptação Psicológica , Individualidade
9.
J Med Imaging (Bellingham) ; 10(Suppl 1): S11910, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37206907

RESUMO

Purpose: Hindsight bias-where people falsely believe they can accurately predict something once they know about it-is a pervasive decision-making phenomenon, including in the interpretation of radiological images. Evidence suggests it is not only a decision-making phenomenon but also a visual perception one, where prior information about an image enhances our visual perception of the contents of that image. The current experiment investigates to what extent expert radiologists perceive mammograms with visual abnormalities differently when they know what the abnormality is (a visual hindsight bias), above and beyond being biased at a decision level. Approach: N=40 experienced mammography readers were presented with a series of unilateral abnormal mammograms. After each case, they were asked to rate their confidence on a 6-point scale that ranged from confident mass to confident calcification. We used the random image structure evolution method, where the images repeated in an unpredictable order and with varied noise, to ensure any biases were visual, not cognitive. Results: Radiologists who first saw an original image with no noise were more accurate in the max noise level condition [area under the curve (AUC)=0.60] than those who first saw the degraded images (AUC=0.55; difference: p=0.005), suggesting that radiologists' visual perception of medical images is enhanced by prior visual experience with the abnormality. Conclusions: Overall, these results provide evidence that expert radiologists experience not only decision level but also visual hindsight bias, and have potential implications for negligence lawsuits.

10.
J Dairy Sci ; 106(6): 3884-3899, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37105877

RESUMO

Our objective was to determine the effect of addition of dipotassium phosphate (DKP) at 3 different thermal treatments on color, viscosity, and sensory properties of 7.5% milk protein-based beverages during 15 d of storage at 4°C. Micellar casein concentrate (MCC) and milk protein concentrate (MPC) containing about 7.5% protein were produced from pasteurized skim milk using a 3×, 3-stage ceramic microfiltration process and a 3×, 3-stage polymeric ultrafiltration membrane process, respectively. The MCC and MPC were each split into 6 batches, based on thermal process and addition of DKP. The 6 batches were no postfiltration heat treatment with added DKP (0.15%), no postfiltration heat without added DKP (0%), postfiltration high-temperature, short time (HTST) with DKP, postfiltration HTST without DKP, postfiltration direct steam injection with DKP, and postfiltration direct steam injection without DKP. The 6 MCC milk-based beverages and the 6 MPC milk-based beverages were stored at 4°C. Viscosity, color, and sensory properties were determined over 15 d of refrigerated storage. MCC- and MPC-based beverages at 7.5% protein with and without 0.15% added dipotassium phosphate were successfully run through an HTST and direct steam injection thermal process. The 7.5% protein MCC-based beverage contained a higher calcium and phosphorus content (2,425 and 1,583 mg/L, respectively) than the 7.5% protein MPC-based beverages (2,141 and 1,338 mg/L, respectively). Pasteurization (HTST) had very little effect on beverage particle size distribution, whereas direct steam injection thermal processing produced protein aggregates with medians in the range of 10 and 175 µm for MPC beverages. A population of casein micelles at about 0.15 µm was found in both MCC- and MPC-based beverages. Larger particles in the 175-µm range were not detected in the MCC beverages. In general, the apparent viscosity (AV) of MCC beverages was higher than MPC beverages. Added DKP increased the AV of both MCC- and MPC-based beverages, while increasing heat treatment decreased AV. The AV of beverages with DKP increased during 15 d of 4°C of storage for both MCC and MPC, whereas there was very little change in AV during storage without DKP and a similar effect was observed for sensory viscosity scores. The L value of beverages was higher with higher heat treatment, but DKP addition decreased L value and sensory opacity greatly. Sulfur-eggy flavors were detected in MPC beverages, but not MCC-based beverages.


Assuntos
Caseínas , Proteínas do Leite , Animais , Proteínas do Leite/análise , Viscosidade , Temperatura Alta , Vapor , Micelas , Fosfatos , Bebidas/análise , Manipulação de Alimentos
11.
Ir Med J ; 116(No.1): 10, 2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36916759

RESUMO

The virtual fracture clinic (VFC) enables the safe, cost-effective delivery of high-quality patient-centred fracture care, whilst reducing hospital footfall. Within our institution, an Outreach VFC was launched, accepting a pre-defined range of trauma referrals from the outreach centre's emergency department (ED). The initial nine months' worth of cases referred to the Outreach VFC were assessed. The injury pattern, time to review, treatment plan and discharge destination of each referred patient were examined. A total of 822 patients were referred to the Outreach VFC during its initial nine months in operation. Owing to COVID-19-related alterations in the patient pathway, 58.1% of patients were referred on to fracture clinic/ED, with 34.4% of patients being referred for physiotherapy input. 44.9% of patients were reviewed at the Outreach VFC within 72 hours of ED presentation, with 88.6% of patients reviewed within 7 days. The Outreach VFC pilot initiative saved the Dublin Midlands Hospitals Group approximately €83,022 over nine months. The Outreach VFC model represents a novel approach to trauma care delivery with advantages for patient and hospital alike. Rural communities serve to benefit from its future implementation and the remote management of orthopaedic trauma. The Outreach VFC model provides a means of delivering safe and timely orthopaedic care whilst maintaining high levels of patient satisfaction.


Assuntos
COVID-19 , Fraturas Ósseas , Humanos , Fraturas Ósseas/terapia , Instituições de Assistência Ambulatorial , Satisfação do Paciente , Encaminhamento e Consulta
12.
Child Maltreat ; 28(3): 407-416, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36724093

RESUMO

This study examined 379 4- to 12-year-old children's answers to any/some and other yes-no questions in forensic interviews about sexual abuse (N = 10,041). Yes-no questions that include the terms any/some (e.g., "Did he say anything?") often implicitly ask for elaboration when the answer is yes ("What did he say?"). However, children may give unelaborated responses to yes-no questions, fail to recognize implicit requests, and falsely respond "no." As predicted, children gave more wh- elaborations in response to any/some questions than other yes-no questions, but younger children elaborated less often than older children. Also as predicted, children responded "no" more often to any/some questions than to other yes-no questions, and more often to "any" than to "some" questions. "No" responses were also more common when children were asked potentially vague anything/something questions and else/other/different questions. The results highlight the potential risks of asking children any/some questions.


Assuntos
Abuso Sexual na Infância , Criança , Pré-Escolar , Humanos , Abuso Sexual na Infância/diagnóstico
13.
Child Maltreat ; 28(1): 55-65, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35025692

RESUMO

Forensic interviewers are taught to pair yes-no questions with open-ended requests for recall in order to reduce the likelihood that they will be misled by false "yes" responses. However, yes-no questions may elicit false "no" responses. Questioning 112 6- to 11-year-old maltreated children about three innocuous events (outside activities, yesterday, last birthday), this study compared the productivity of paired yes-no questions about perceptions, conversations, and actions involving the hands and mouth (e.g., "Did you say anything?") with wh-questions (e.g., "What did you say?"). The wh-questions presupposed that children had content to provide, but did not specify that content. Children were twice as likely to deny content and half as likely to provide novel information when interviewers asked them yes-no questions. Younger children were more inclined than older children to deny content and give unelaborated "yes" responses. The results support further research into the potential for suppositional wh-questions to increase child witnesses' productivity.


Assuntos
Abuso Sexual na Infância , Maus-Tratos Infantis , Criança , Humanos , Adolescente , Comunicação , Rememoração Mental , Registros
14.
Child Maltreat ; 28(2): 275-285, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35623629

RESUMO

Adolescents tend to be neglected in research examining child sexual abuse (CSA) interviews, yet are often said to be particularly reluctant. This study examined reluctance among 119 10- to 17-year-old females questioned about suspected CSA (n = 25,942 responses), utilizing a scheme identifying previously overlooked types of reluctance in commercially sexually exploited (CSE) youth. In contrast to the CSE youth in a prior study, in which 26% of responses were reluctant, only 8% of CSA victims' responses expressed reluctance. Reluctance was unrelated to age, abuse characteristics, and don't know (IDK) responding. Greater reluctance (but not IDK responding) was related to disclosure of fewer characteristics of abuse. Virtually all youth (93%) had disclosed prior to the interview, in contrast to previous studies examining reluctance among adolescent victims of internet-initiated sexual abuse and CSE. The way in which abuse is discovered may better explain reluctance than the age of the alleged victims.


Assuntos
Abuso Sexual na Infância , Maus-Tratos Infantis , Vítimas de Crime , Feminino , Criança , Adolescente , Humanos , Abuso Sexual na Infância/diagnóstico , Emoções , Revelação , Comportamento Sexual
15.
Child Maltreat ; 28(2): 265-274, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35607755

RESUMO

Forensic interviewers ask children broad input-free recall questions about individual episodes in order to elicit complete narratives, often asking about "the first time," "the last time," and "one time." An overlooked problem is that the word "time" is potentially ambiguous, referring both to a particular episode and to conventional temporal information. We examined 191 6-9-year-old maltreated children's responses to questions about recent events varying the wording of the invitations, either asking children to "tell me about" or "tell me what happened" one time/the first time/the last time the child experienced recent recurrent events. Additionally, half of the children were asked a series of "when" questions about recurrent events before the invitations. Children were several times more likely to provide exclusively conventional temporal information to "tell me about" invitations compared to "tell me what happened" invitations, and asking "when" questions before the invitations increased children's tendency to give exclusively conventional temporal information. Children who answered a higher proportion of "when" questions with conventional temporal information were also more likely to do so in response to the invitations. The results suggest that children may often fail to provide narrative information because they misinterpret invitations using the word "time."


Assuntos
Abuso Sexual na Infância , Maus-Tratos Infantis , Humanos , Criança , Rememoração Mental , Narração
16.
Appl Dev Sci ; 26(4): 679-688, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36339797

RESUMO

Forensic interviewers are encouraged to elicit a practice narrative from children in order to train them to answer free recall questions with narrative information. Although asking children about their last birthday has been recommended, concerns have been raised that many children will have nothing to report. This study asked 994 4- to 9-year-old maltreated and non-maltreated children to recall their last birthday. Although a fair number of children initially failed to recall information (9%), virtually all children recalled information with persistent encouragement (99%). Younger children and maltreated children were less responsive and spoke less, but nevertheless, 93% of the youngest children (4-year-olds) and 97% of maltreated children recalled information with persistent encouragement. The results suggest that children's failures to recall information about birthdays are predominantly attributable to a failure to provide additional support.

17.
Vision Res ; 201: 108123, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36193605

RESUMO

The input from the two eyes is combined in the brain. In this combination, the relative strength of the input from each eye is determined by the ocular dominance. Recent work has shown that this dominance can be temporarily shifted. Covering one eye with an eye patch for a few hours makes its contribution stronger. It has been proposed that this shift can be enhanced by exercise. Here, we test this hypothesis using a dichoptic surround suppression task, and with exercise performed according to American College of Sport Medicine guidelines. We measured detection thresholds for patches of sinusoidal grating shown to one eye. When an annular mask grating was shown simultaneously to the other eye, thresholds were elevated. The difference in the elevation found in each eye is our measure of relative eye dominance. We made these measurements before and after 120 min of monocular deprivation (with an eye patch). In the control condition, subjects rested during this time. For the exercise condition, 30 min of exercise were performed at the beginning of the patching period. This was followed by 90 min of rest. We find that patching results in a shift in ocular dominance that can be measured using dichoptic surround suppression. However, we find no effect of exercise on the magnitude of this shift. We further performed a meta-analysis on the four studies that have examined the effects of exercise on the dominance shift. Looking across these studies, we find no evidence for such an effect.


Assuntos
Dominância Ocular , Visão Monocular , Humanos , Plasticidade Neuronal , Exercício Físico , Olho , Privação Sensorial , Visão Binocular
18.
Catal Sci Technol ; 12: 3804-3816, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35965882

RESUMO

Contiguous metal foams offer a multitude of advantages over conventional powders as supports for nanostructured heterogeneous catalysts; most critically a preformed 3-D porous framework ensuring full directional coverage of supported catalyst, and intrinsic ease of handling and recyclability. Nonetheless, metal foams remain comparatively underused in thermal catalysis compared to more conventional supports such as amorphous carbon, metal oxides, zeolites and more recently MOFs. Herein, we demonstrate a facile preparation of highly-reactive, robust, and easy to handle Ni foam-supported Cu-based metal catalysts. The highly sustainable synthesis requires no specialized equipment, no surfactants or additive redox reagents, uses water as solvent, and CuCl2(H2O)2 as precursor. The resulting material seeds as well-separated micro-crystalline Cu2(OH)3Cl evenly covering the Ni foam. Calcination above 400 °C transforms the Cu2(OH)3Cl to highly porous CuO. All materials display promising activity towards the reduction of 4-nitrophenol and methyl orange. Notably, our leading CuO-based material displays 4-nitrophenol reduction activity comparable with very reactive precious-metal based systems. Recyclability studies highlight the intrinsic ease of handling for the Ni foam support, and our results point to a very robust, highly recyclable catalyst system.

19.
Trials ; 23(1): 581, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35858894

RESUMO

BACKGROUND: Cerebrospinal fluid (CSF) leakage is a frequent and challenging complication in neurosurgery, especially in the posterior fossa, with a prevalence of 8%. It is associated with substantial morbidity and increased healthcare costs. A novel dural sealant patch (LIQOSEAL) was developed for watertight dural closure. The objective of this study is to clinically assess the safety and effectiveness of LIQOSEAL as a means of reducing intra- as well as postoperative CSF leakage in patients undergoing elective posterior fossa intradural surgery with a dural closure procedure compared to the best currently available dural sealants. METHODS: We will conduct a two-arm, randomized controlled, multicenter study with a 90-day follow-up. A total of 228 patients will be enrolled in 19 sites, of which 114 will receive LIQOSEAL and 114 an FDA-approved PEG sealant. The composite primary endpoint is defined as intraoperative CSF leakage at PEEP 20 cm H2O, percutaneous CSF leakage within 90 days of, wound infection within 90 days of or pseudomeningocele of more than 20cc on MRI or requiring intervention. We hypothesize that the primary endpoint will not be reached by more than 10 patients (9%) in the investigational arm, which will demonstrate non-inferiority of LIQOSEAL compared to control. DISCUSSION: This trial will evaluate whether LIQOSEAL is non-inferior to control as a means of reducing CSF leakage and safety TRIAL REGISTRATION: ClinicalTrials.gov NCT04086550 . Registered on 11 September 2019.


Assuntos
Vazamento de Líquido Cefalorraquidiano , Dura-Máter , Vazamento de Líquido Cefalorraquidiano/diagnóstico , Vazamento de Líquido Cefalorraquidiano/etiologia , Vazamento de Líquido Cefalorraquidiano/prevenção & controle , Dura-Máter/cirurgia , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Humanos , Estudos Multicêntricos como Assunto , Procedimentos Neurocirúrgicos/efeitos adversos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/cirurgia , Período Pós-Operatório , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
J Am Chem Soc ; 144(26): 11870-11877, 2022 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-35731921

RESUMO

Radical-mediated transformations have emerged as powerful methods for the synthesis of rare and unnatural branched, deoxygenated, and isomeric sugars. Here, we describe a radical-mediated axial-to-equatorial alcohol epimerization method to transform abundant glycans into rare isomers. The method delivers highly predictable and selective reaction outcomes that are complementary to other sugar isomerization methods. The synthetic utility of isomer interconversion is showcased through expedient glycan synthesis, including one-step glycodiversification. Mechanistic studies reveal that both site- and diastereoselectivities are achieved by highly selective H atom abstraction of equatorially disposed α-hydroxy C-H bonds.


Assuntos
Carboidratos , Açúcares , Carboidratos/química , Hexoses , Isomerismo , Polissacarídeos/química , Açúcares/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...