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1.
Clin Radiol ; 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39443240

RESUMO

AIMS: To investigate radiology staff perceptions of an AI tool for chest radiography triage, flagging findings suspicious for lung cancer to expedite same-day CT chest examination studies. MATERIALS AND METHODS: Surveys were distributed to all radiology staff at three time points: at pre-implementation, one month and also seven months post-implementation of artificial intelligence (AI). Survey questions captured feedback on AI use and patient impact. RESULTS: Survey response rates at the three time periods were 23.1% (45/195), 14.9% (29/195) and 27.2% (53/195), respectively. Most respondents initially anticipated AI to be time-saving for the department and patient (50.8%), but this shifted to faster follow-up care for patients after AI implementation (51.7%). From the free text comments, early apprehension about job role changes evolved into frustration regarding technical integration challenges after implementation. This later transitioned to a more balanced view of recognised patient benefits versus minor ongoing logistical issues by the late post-implementation stage. There was majority disagreement across all survey periods that AI could be considered to be used autonomously (53.3-72.5%), yet acceptance grew for personal AI usage if staff were to be patients themselves (from 31.1% pre-implementation to 47.2% post-implementation). CONCLUSION: Successful AI integration in radiology demands active staff engagement, addressing concerns to transform initial mixed excitement and resistance into constructive adaptation. Continual feedback is vital for refining AI deployment strategies, ensuring its beneficial and sustainable incorporation into clinical care pathways.

2.
Small ; 19(33): e2300659, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37072896

RESUMO

Controlling diamond structures with nanometer precision is fundamentally challenging owing to their extreme and far-from-equilibrium synthetic conditions. State-of-the-art techniques, including detonation, chemical vapor deposition, mechanical grinding, and high-pressure-high-temperature synthesis, yield nanodiamond particles with a broad distribution of sizes. Despite many efforts, the direct synthesis of nanodiamonds with precisely controlled diameters remains elusive. Here the geochemistry-inspired synthesis of sub-5 nm nanodiamonds with sub-nanometer size deviation is described. High-pressure-high-temperature treatment of uniform iron carbide nanoparticles embedded in iron oxide matrices yields nanodiamonds with tunable diameters down to 2.13 and 0.22 nm standard deviation. A self-limiting, redox-driven, and diffusion-controlled solid-state reaction mechanism is proposed and supported by in situ X-ray diffraction, ex situ characterizations, and computational modeling. This work provides a unique mechanism for the precise control of nanostructured diamonds under extreme conditions and paves the road for the full realization of their potential in emerging technologies.

3.
Phys Rev Lett ; 130(13): 132502, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37067317

RESUMO

The new isotope ^{241}U was synthesized and systematic atomic mass measurements of nineteen neutron-rich Pa-Pu isotopes were performed in the multinucleon transfer reactions of the ^{238}U+^{198}Pt system at the KISS facility. The present experimental results demonstrate the crucial role of the multinucleon transfer reactions for accessing unexplored neutron-rich actinide isotopes toward the N=152 shell gap in this region of nuclides.

4.
Phys Rev Lett ; 130(1): 012501, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36669221

RESUMO

The atomic masses of ^{55}Sc, ^{56,58}Ti, and ^{56-59}V have been determined using the high-precision multireflection time-of-flight technique. The radioisotopes have been produced at RIKEN's Radioactive Isotope Beam Factory (RIBF) and delivered to the novel designed gas cell and multireflection system, which has been recently commissioned downstream of the ZeroDegree spectrometer following the BigRIPS separator. For ^{56,58}Ti and ^{56-59}V, the mass uncertainties have been reduced down to the order of 10 keV, shedding new light on the N=34 shell effect in Ti and V isotopes by the first high-precision mass measurements of the critical species ^{58}Ti and ^{59}V. With the new precision achieved, we reveal the nonexistence of the N=34 empirical two-neutron shell gaps for Ti and V, and the enhanced energy gap above the occupied νp_{3/2} orbit is identified as a feature unique to Ca. We perform new Monte Carlo shell model calculations including the νd_{5/2} and νg_{9/2} orbits and compare the results with conventional shell model calculations, which exclude the νg_{9/2} and the νd_{5/2} orbits. The comparison indicates that the shell gap reduction in Ti is related to a partial occupation of the higher orbitals for the outer two valence neutrons at N=34.


Assuntos
Nêutrons , Titânio
5.
Clin Exp Dermatol ; 47(2): 335-342, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34431555

RESUMO

BACKGROUND: Hidradenitis suppurativa (HS) is a devastating chronic inflammatory skin disease with frequent recurrences. Various systemic treatments and procedures have been used but the efficacy of fractional microneedling radiofrequency (FMR) has not been reported. AIM: To evaluate the clinical and histological efficacy of FMR in the treatment of HS lesions. METHODS: An 8-week, prospective, split-body, unblinded study was conducted, which enrolled 10 adult patients with mild to moderate HS to receive 3 sessions of FMR treatment biweekly. HS severity was assessed using the number and type of lesions, HS Physician Global Assessment (HS-PGA) and the modified Sartorius score (mSS). Skin biopsies were performed on participants to assess change in inflammation before and after FMR. RESULTS: Severity of HS was significantly reduced on the FMR-treated side of the body, but not on the control side. Inflammatory HS lesions were significantly reduced after 4 weeks, while HS-PGA and mSS were significantly decreased after 6 weeks. Immunohistochemistry staining showed decreased expression of inflammatory markers including neutrophil elastases, interleukin (IL)-8 and IL-17, tumour necrosis factor-α, transforming growth factor-ß1 and matrix metalloproteinases. CONCLUSION: FMR may be a viable treatment option for mild to moderate HS.


Assuntos
Hidradenite Supurativa/terapia , Terapia por Radiofrequência/métodos , Adolescente , Adulto , Idade de Início , Feminino , Hidradenite Supurativa/imunologia , Hidradenite Supurativa/patologia , Humanos , Interleucinas/análise , Masculino , Metaloproteinases da Matriz/análise , Agulhas , Projetos Piloto , Estudos Prospectivos , Terapia por Radiofrequência/instrumentação , Resultado do Tratamento , Fator de Necrose Tumoral alfa/análise
6.
J Eur Acad Dermatol Venereol ; 36(8): 1171-1177, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35246887

RESUMO

Anti-drug antibodies (ADAs) can form with certain biological medications, but their clinical significance is not fully understood. ADA formation in psoriasis patients treated with IL-23 inhibitors was evaluated, looking at the incidence of ADAs, impact on clinical outcomes and association with adverse events. A systematic search of PubMed, Cochrane and Embase databases yielded 318 articles, which were manually reviewed. A total of 19 articles met the eligibility criteria. The incidence of ADAs with the IL-23 inhibitors was as follows: 4.1-14.7% with guselkumab, 141-31% with risankizumab and 6.51-18% with tildrakizumab. The incidence of neutralizing antibodies ranged from 01-0.6% with guselkumab, 21-16% with risankizumab and 2.5 to 3.2% with tildrakizumab. There was no evidence of reduced efficacy of psoriasis treatment with ADA presence alone. However, some studies found a reduction in clinical response with high ADA titres or with the presence of neutralizing antibodies. A few studies reported that patients with ADAs to guselkumab and risankizumab had a higher incidence of injection site reactions (ISRs). There do not appear to be other adverse events associated with ADAs with IL-23 inhibitors. Testing for presence of ADAs alone in this patient group does not appear to be predictive of treatment response. Clinically, it may be more productive to test for neutralizing antibodies or ADA titre values, although further investigation is required to show a definitive correlation.


Assuntos
Inibidores de Interleucina , Psoríase , Anticorpos Neutralizantes/uso terapêutico , Humanos , Interleucina-23 , Psoríase/tratamento farmacológico
7.
J Dairy Sci ; 105(3): 2301-2314, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34955263

RESUMO

The objective of this experiment was to evaluate the effects of supplementing a rumen-protected source of Met, N-acetyl-l-methionine (NALM), on lactational performance and nitrogen metabolism in early- to mid-lactation dairy cows. Sixty multiparous Holstein dairy cows in early lactation (27 ± 4.3 d in milk, SD) were assigned to 4 treatments in a randomized complete block design. Cows were blocked by actual milk yield. Treatments were as follows: (1) no NALM (control); (2) 15 g/d of NALM (NALM15); (3) 30 g/d of NALM (NALM30); and (4) 45 g/d of NALM (NALM45). Diets were formulated using a Cornell Net Carbohydrate and Protein System (CNCPS) v.6.5 model software to meet or exceed nutritional requirements of lactating dairy cows producing 42 kg/d of milk and to undersupply metabolizable Met (control) or supply incremental amounts of NALM. The digestible Met (dMet) supply for control, NALM15, NALM30, and NALM45 were 54.7, 59.8, 64.7, and 72.2 g/d, respectively. The supply of dMet was 88, 94, 104, and 115% of dMet requirement for control, NALM15, NALM30, and NALM45, respectively. Milk yield data were collected, dry matter intake (DMI) was measured daily, and milk samples were collected twice per week for 22 wk. Blood, ruminal fluid, urine, and fecal samples were collected during the covariate period and during wk 4, 8, and 16. Data were analyzed using the GLIMMIX procedure of SAS (SAS Institute) using covariates in the model for all variables except body weight. Linear, quadratic, and cubic contrasts were also tested. Treatments did not affect DMI, milk yield, and milk component concentration and yield; however, feed efficiency expressed as milk yield per DMI and 3.5% fat-corrected milk per DMI were quadratically affected, with greater response observed for NALM15 and NALM30 compared with control. Acetate proportion linearly increased, whereas propionate proportion linearly decreased with NALM supplementation. Blood urea nitrogen linearly decreased with NALM supplementation. Total plasma essential AA concentrations were quadratically affected, as greater values were observed for control and NALM45 than other treatments. Plasma Met concentration was quadratically affected as lower levels were observed with NALM15, whereas Met concentrations increased with NALM45 compared with control. Nitrogen utilization efficiency and apparent total-tract nutrient digestibility were not affected by treatment. Supplementation of NALM at 15 or 30 g/head per day resulted in the greatest improvements in feed efficiency without affecting N metabolism of early- to mid-lactation dairy cows.


Assuntos
Lactação , Rúmen , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Suplementos Nutricionais , Feminino , Lactação/fisiologia , Metionina , Leite/metabolismo , Rúmen/metabolismo
8.
J Dairy Sci ; 105(1): 313-328, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34756433

RESUMO

Two experiments were conducted to investigate the production effects of N-acetyl-l-methionine (NALM; experiment 1) and to estimate its bioavailability (BA) and rumen escape (RE; experiment 2), respectively, in lactating dairy cows. In experiment 1, 18 multiparous Holstein cows were used in a replicated, 3 × 3 Latin square design experiment with three 28-d periods. Treatments were (1) basal diet estimated to supply 45 g/d digestible Met (dMet) or 1.47% of metabolizable protein (MP; control), (2) basal diet top-dressed with 32 g/d of NALM to achieve dMet supply of 2.2% of MP, and (3) basal diet top-dressed with 56 g/d of NALM to achieve dMet supply of 2.6% of MP. The NALM treatments supplied estimated 17 and 29 g/d dMet from NALM, respectively, based on manufacturer's specifications. In experiment 2, 4 rumen-cannulated lactating Holstein cows were used in a 4 × 4 Latin square design experiment with four 12-d periods. A 12-d period for baseline data collection and 4 d for determination of RE of NALM preceded the Latin square experiment. For determination of RE, 30 g of NALM were dosed into the rumen simultaneously with Cr-EDTA (used as a rumen fluid kinetics marker) and samples of ruminal contents were collected at 0 (before dosing), 1, 2, 4, 6, 8, 10, 14, 18, and 24 h after dosing. Rumen escape of NALM was calculated using the estimated passage rate based on the measured Cr rate of disappearance. Bioavailability of abomasally dosed NALM was determined using the area under the curve of plasma Met concentration technique. Two doses of l-Met (providing 7.5 and 15 g of dMet) and 2 doses of NALM (11.2 and 14.4 g of dMet) were separately pulse-dosed into the abomasum of the cows and blood was collected from the jugular vein for Met concentration analysis at 0 (before dosing), 1, 2, 4, 6, 8, 10, 12, 14, 18, and 24 h after dosing. Supplementation of NALM did not affect DMI, milk yield, feed efficiency, or milk protein and lactose concentrations and yields in experiment 1. Milk fat concentration and energy-corrected milk yield decreased linearly with NALM dose. Plasma Met concentration was not affected by NALM dose. The estimated relative BA of abomasally dosed NALM (experiment 2) was 50% when dosed at 14.4 g/cow (11.2 g/d dMet from NALM) and 24% when dosed at 28.8 g/cow (14.4 g/d dMet from NALM). The estimated RE of NALM was 19% based on the measured kp of Cr at 11%/h. The total availability of ingested NALM was estimated at 9.5% for the lower NALM dose when taking into account RE (19%) and bioavailability in the small intestine (50%). Overall, NALM supplementation to mid-lactation dairy cows fed a MP-adequate basal diet below NRC (2001) recommendations (45 g/d or 1.47% Met of MP) decreased milk fat and energy-corrected milk yields but did not affect milk or milk true protein yields. Further evaluation of BA of NALM at different doses is warranted. In addition, intestinal conversion of NALM to Met needs additional investigation to establish a possible saturation of the enzyme aminoacylase I at higher NALM doses.


Assuntos
Ração Animal , Lactação , Ração Animal/análise , Animais , Disponibilidade Biológica , Bovinos , Dieta/veterinária , Proteínas Alimentares/metabolismo , Suplementos Nutricionais , Feminino , Metionina/metabolismo , Rúmen/metabolismo
9.
Rhinology ; 60(3): 188-199, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35901492

RESUMO

BACKGROUND: Olfactory dysfunction is a cardinal symptom of COVID-19 infection, however, studies assessing long-term olfactory dysfunction are limited and no randomised-controlled trials (RCTs) of early olfactory training have been conducted. METHODOLOGY: We conducted a prospective, multi-centre study consisting of baseline psychophysical measurements of smell and taste function. Eligible participants were further recruited into a 12-week RCT of olfactory training versus control (safety information). Patient-reported outcomes were measured using an electronic survey and BSIT at baseline and 12 weeks. An additional 1-year follow-up was open to all participants. RESULTS: 218 individuals with a sudden loss of sense of smell of at least 4-weeks were recruited. Psychophysical smell loss was observed in only 32.1%; 63 participants were recruited into the RCT. The absolute difference in BSIT improvement after 12 weeks was 0.45 higher in the intervention arm. 76 participants completed 1-year follow-up; 10/19 (52.6%) of participants with an abnormal baseline BSIT test scored below the normal threshold at 1-year, and 24/29 (82.8%) had persistent parosmia. CONCLUSIONS: Early olfactory training may be helpful, although our findings are inconclusive. Notably, a number of individuals who completed the 1-year assessment had persistent smell loss and parosmia at 1-year. As such, both should be considered important entities of long-Covid and further studies to improve management are highly warranted.


Assuntos
COVID-19 , Transtornos do Olfato , Humanos , Olfato , COVID-19/complicações , Anosmia/etiologia , Treinamento Olfativo , Transtornos do Olfato/etiologia , Transtornos do Olfato/diagnóstico
10.
J Am Chem Soc ; 143(7): 2660-2664, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33502185

RESUMO

While nanoscale mimics of peroxidase have been extensively developed over the past decade or so, their catalytic efficiency as a key parameter has not been substantially improved in recent years. Herein, we report a class of highly efficient peroxidase mimic-nickel-platinum nanoparticles (Ni-Pt NPs) that consist of nickel-rich cores and platinum-rich shells. The Ni-Pt NPs exhibit a record high catalytic efficiency with a catalytic constant (Kcat) as high as 4.5 × 107 s-1, which is ∼46- and 104-fold greater than the Kcat values of conventional Pt nanoparticles and natural peroxidases, respectively. Density functional theory calculations reveal that the unique surface structure of Ni-Pt NPs weakens the adsorption of key intermediates during catalysis, which boosts the catalytic efficiency. The Ni-Pt NPs were applied to an immunoassay of a carcinoembryonic antigen that achieved an ultralow detection limit of 1.1 pg/mL, hundreds of times lower than that of the conventional enzyme-based assay.

11.
Ann Oncol ; 32(4): 552-559, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33352201

RESUMO

BACKGROUND: Current treatment options for peripheral T-cell lymphomas (PTCLs) in the relapsed/refractory setting are limited and demonstrate modest response rates with rare achievement of complete response (CR). PATIENTS AND METHODS: This phase I/II study (NCT03052933) investigated the safety and efficacy of copanlisib, a phosphatidylinositol 3-kinase-α/-δ inhibitor, in combination with gemcitabine in 28 patients with relapsed/refractory PTCL. Patients received escalating doses of intravenous copanlisib on days 1, 8, and 15, administered concomitantly with fixed-dose gemcitabine (1000 mg/m2 on days 1 and 8) in 28-day cycles. RESULTS: Dose-limiting toxicity was not observed in the dose-escalation phase and 60 mg copanlisib was selected for phase II evaluation. Twenty-five patients were enrolled in phase II of the study. Frequent grade ≥3 adverse events (AEs) included transient hyperglycemia (57%), neutropenia (45%), thrombocytopenia, (37%), and transient hypertension (19%). However, AEs were manageable, and none were fatal. The overall response rate was 72% with a CR rate of 32%. Median duration of response was 8.2 months, progression-free survival was 6.9 months, and median overall survival was not reached. Combination treatment produced a greater CR rate in patients with angioimmunoblastic T-cell lymphoma than those with PTCL-not otherwise specified (55.6% versus 15.4%, respectively, P = 0.074) and progression-free survival was significantly longer (13.0 versus 5.1 months, respectively, P = 0.024). In an exploratory gene mutation analysis of 24 tumor samples, TSC2 mutation was present in 25% of patients and occurred exclusively in responders. CONCLUSION: The combination of copanlisib and gemcitabine is a safe and effective treatment option in relapsed/refractory PTCLs and represents an important new option for therapy in this rare group of patients.


Assuntos
Linfoma de Células T Periférico , Desoxicitidina/análogos & derivados , Humanos , Recidiva Local de Neoplasia/tratamento farmacológico , Pirimidinas , Quinazolinas , Resultado do Tratamento , Gencitabina
12.
Mol Genet Metab ; 132(4): 234-243, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33642210

RESUMO

BACKGROUND: Recent years have witnessed a considerable increase in clinical trials of new investigational agents for Fabry disease (FD). Several trials investigating different agents are currently in progress; however, lack of standardisation results in challenges to interpretation and comparison. To facilitate the standardisation of investigational programs, we have developed a common framework for future clinical trials in FD. METHODS AND FINDINGS: A broad consensus regarding clinical outcomes and ways to measure them was obtained via the Delphi methodology. 35 FD clinical experts from 4 continents, representing 3389 FD patients, participated in 3 rounds of Delphi procedure. The aim was to reach a consensus regarding clinical trial design, best treatment comparator, clinical outcomes, measurement of those clinical outcomes and inclusion and exclusion criteria. Consensus results of this initiative included: the selection of the adaptative clinical trial as the ideal study design and agalsidase beta as ideal comparator treatment due to its longstanding use in FD. Renal and cardiac outcomes, such as glomerular filtration rate, proteinuria and left ventricular mass index, were prioritised, whereas neurological outcomes including cerebrovascular and white matter lesions were dismissed as a primary or secondary outcome measure. Besides, there was a consensus regarding the importance of patient-related outcomes such as general quality of life, pain, and gastrointestinal symptoms. Also, unity about lysoGb3 and Gb3 tissue deposits as useful surrogate markers of the disease was obtained. The group recognised that cardiac T1 mapping still has potential but requires further development before its widespread introduction in clinical trials. Finally, patients with end-stage renal disease or renal transplant should be excluded unless a particular group for them is created inside the clinical trial. CONCLUSION: This consensus will help to shape the future of clinical trials in FD. We note that the FDA has, coincidentally, recently published draft guidelines on clinical trials in FD and welcome this contribution.


Assuntos
Ensaios Clínicos como Assunto , Terapia de Reposição de Enzimas , Doença de Fabry/tratamento farmacológico , Rim/metabolismo , Adulto , Consenso , Técnica Delphi , Doença de Fabry/genética , Doença de Fabry/metabolismo , Doença de Fabry/patologia , Feminino , Globosídeos/uso terapêutico , Glicolipídeos/uso terapêutico , Humanos , Isoenzimas/genética , Rim/efeitos dos fármacos , Rim/patologia , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Esfingolipídeos/uso terapêutico , Resultado do Tratamento , Triexosilceramidas/uso terapêutico , alfa-Galactosidase/genética
13.
J Neuropsychiatry Clin Neurosci ; 33(3): 225-229, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33706533

RESUMO

OBJECTIVE: The investigators examined the presence of disrupted sleep in acquired brain injury (ABI) and the utility of a mobile health program, MySleepScript, as an effective clinical tool to detect sleep disturbances. METHODS: A cross-sectional pilot study of MySleepScript, a customizable electronic battery of validated sleep questionnaires, was conducted. Participants were recruited at the Acquired Brain Injury Clinic at Johns Hopkins Bayview Medical Center. RESULTS: Sixty-eight adults with ABI (mean age, 46.3 years [SD=14.8]) participated in the study, with a mean completion time of 16.6 minutes (SD=5.4). Time to completion did not differ on individual completion or staff assistance. The mean score on the Pittsburgh Sleep Quality Index was 9.2 (SD=4.7); 83.9% of individuals had poor sleep quality (defined as a score >5). Insomnia Severity Index scores indicated moderate to severe insomnia in 45% of participants; 36.5% of participants screened positive for symptoms concerning sleep apnea, while 39.3% of individuals screened positive for restless legs syndrome. CONCLUSIONS: Poor sleep quality was highly prevalent in this ABI cohort. MySleepScript may be an effective method of assessing for sleep disturbance in ABI. Further efforts to identify sleep disorders in this patient population should be pursued to optimize ABI management.


Assuntos
Lesões Encefálicas/complicações , Computadores de Mão , Transtornos do Sono-Vigília , Estudos de Coortes , Estudos Transversais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Encaminhamento e Consulta , Síndrome das Pernas Inquietas/diagnóstico , Distúrbios do Início e da Manutenção do Sono/diagnóstico , Transtornos do Sono-Vigília/diagnóstico , Transtornos do Sono-Vigília/epidemiologia , Inquéritos e Questionários , Estados Unidos/epidemiologia
14.
J Am Chem Soc ; 142(16): 7480-7486, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32239925

RESUMO

To discover the nonlinear optical (NLO) materials with strong second harmonic generation (SHG), the design of NLO-active molecular units with large polarization is considered as a common strategy. Herein, we propose that the local structural distortion induced with vacancies, apart from the NLO-active units, can be employed to improve the NLO effect in solids as well. Accordingly, a new tungsten bronze (TB) oxide, Pb2(Pb0.15Li0.7□0.15)Nb5O15 (□ representing vacancies), is successfully designed and prepared, which exhibits a strong SHG response of 39 times that of KH2PO4. The detailed analysis reveals that the local structural distortions enhanced by the vacancies in PLN strengthen the local dipole moments of neighboring NbO6 octahedra, and thus significantly prompt the SHG effect. Moreover, a series of new TB compounds with large NLO effects are discovered by this molecular design strategy, which are perspectives for new NLO materials synthesis.

15.
Electrophoresis ; 41(7-8): 630-637, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31709550

RESUMO

In this work, we present a step-by-step workflow for the fabrication of 2D hexagonal boron nitride (h-BN) nanopores which are then used to sense holo-human serum transferrin (hSTf) protein at pH ∼8 under applied voltages ranging from +100 mV to +800 mV. 2D nanopores are often used for DNA, however, there is a great void in the literature for single-molecule protein sensing and this, to the best of our knowledge, is the first time where h-BN-a material with large band-gap, low dielectric constant, reduced parasitic capacitance and minimal charge transfer induced noise-is used for protein profiling. The corresponding ΔG (change in pore conductance due to analyte translocation) profiles showed a bimodal Gaussian distribution where the lower and higher ΔG distributions were attributed to (pseudo-) folded and unfolded conformations respectively. With increasing voltage, the voltage induced unfolding increased (evident by decrease in ΔG) and plateaued after ∼400 mV of applied voltage. From the ΔG versus voltage profile corresponding to the pseudo-folded state, we calculated the molecular radius of hSTf, and was found to be ∼3.1 nm which is in close concordance with the literature reported value of ∼3.25 nm.


Assuntos
Compostos de Boro/química , Técnicas Eletroquímicas/métodos , Nanoporos , Transferrina/química , Desenho de Equipamento , Humanos , Conformação Proteica , Termodinâmica , Titânio , Transferrina/análise
16.
Phys Rev Lett ; 124(22): 226403, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32567905

RESUMO

Light can be strongly confined in subwavelength spatial regions through the interaction with plasmons, the collective electronic modes appearing in metals and semiconductors. This confinement, which is particularly important in the terahertz spectral region, amplifies light-matter interaction and provides a powerful mechanism for efficiently generating nonlinear optical phenomena. These effects are particularly relevant in graphene and topological insulators, where massless Dirac fermions show a naturally nonlinear optical behavior in the terahertz range. The strong interaction scenario has been considered so far from the point of view of light. In this Letter, we investigate instead the effect of strong interaction on the plasmon itself. In particular, we will show that Dirac plasmons in Bi_{2}Se_{3} topological insulator are strongly renormalized when excited by high-intensity terahertz radiation by displaying a huge red-shift down to 60% of its characteristic frequency. This opens the road towards tunable terahertz nonlinear optical devices based on topological insulators.

17.
Phys Rev Lett ; 125(19): 192505, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33216598

RESUMO

Mass-separated ^{187}Ta_{114} in a high-spin isomeric state has been produced for the first time by multinucleon transfer reactions, employing an argon gas-stopping cell and laser ionization. Internal γ rays revealed a T_{1/2}=7.3±0.9 s isomer at 1778±1 keV, which decays through a rotational band with perturbations associated with the approach to a prolate-oblate shape transition. Model calculations show less influence from triaxiality compared to heavier elements in the same mass region. The isomer-decay reduced E2 hindrance factor f_{ν}=27±1 supports the interpretation that axial symmetry is approximately conserved.

18.
Eur Radiol ; 30(3): 1378-1384, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31776746

RESUMO

More than half of us will need a magnetic resonance imaging (MRI) scan in our lifetimes. MRI is an unmatched diagnostic test for an expanding range of indications including neurological and musculoskeletal disorders, cancer diagnosis, and treatment planning. Unfortunately, patients with cardiac pacemakers or defibrillators have historically been prevented from having MRI because of safety concerns. This results in delayed diagnoses, more invasive investigations, and increased cost. Major developments have addressed this-newer devices are designed to be safe in MRI machines under specific conditions, and older legacy devices can be scanned provided strict protocols are followed. This service however remains difficult to deliver sustainably worldwide: MRI provision remains grossly inadequate because patients are less likely to be referred, and face difficulties accessing services even when referred. Barriers still exist but are no longer technical. These include logistical hurdles (poor cardiology and radiology interaction at physician and technician levels), financial incentives (re-imbursement is either absent or fails to acknowledge the complexity), and education (physicians self-censor MRI requests). This article therefore highlights the recent changes in the clinical, logistical, and regulatory landscape. The aim of the article is to enable and encourage healthcare providers and local champions to build MRI services urgently for cardiac device patients, so that they may benefit from the same access to MRI as everyone else. KEY POINTS: • There is now considerable evidence that MRI can be provided safely to patients with cardiac implantable electronic devices (CIEDs). However, the volume of MRI scans delivered to patients with CIEDs is fifty times lower than that of the estimated need, and patients are approximately fifty times less likely to be referred. • Because scans for this patient group are frequently for cancer diagnosis and treatment planning, MRI services need to develop rapidly, but the barriers are no longer technical. • New services face logistical, educational, and financial hurdles which can be addressed effectively to establish a sustainable service at scale.


Assuntos
Competência Clínica , Contraindicações de Procedimentos , Desfibriladores Implantáveis , Comunicação Interdisciplinar , Imageamento por Ressonância Magnética/métodos , Marca-Passo Artificial , Encaminhamento e Consulta , Mecanismo de Reembolso , Cardiologia , Eletrônica , Desenho de Equipamento , Disparidades em Assistência à Saúde , Humanos , Radiologia
19.
Clin Radiol ; 75(8): 641.e19-641.e27, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32291081

RESUMO

AIM: To assess the predictive value of preoperative residual mammographic microcalcifications for residual tumours after neoadjuvant chemotherapy (NAC) for breast cancer. MATERIALS AND METHODS: This single-centre retrospective study included breast cancer patients who underwent NAC and demonstrated suspicious microcalcifications within or near the tumour bed on mammography from June 2015 to August 2018. The residual microcalcifications and remnant lesion on magnetic resonance imaging (MRI) were correlated with histopathological findings of residual tumours and immunohistochemical markers. RESULTS: A total of 96 patients were included. Ten patients achieved pathological complete response (pCR) and previous suspicious microcalcifications were associated with benign pathology in 10.4% (10/96) of the patients. In the remaining 86 patients who did not achieve pCR, 61.5% (59/96) of the residual microcalcifications were associated with invasive or in situ carcinoma and 28.1% (27/96) with benign pathology. Hormone receptor-positive (HR+) patients had the highest proportion of residual malignant microcalcifications compared to HR- patients (48.9% versus 13.5%, respectively; p=0.019). MRI correlated better than residual microcalcifications on mammography in predicting residual tumour extent in all subtypes (ICC=0.709 versus 0.365). MRI also showed higher correlation with residual tumour size for the HR-/HER2+ and HR-/HER2- subtype (ICC=0.925 and 0.876, respectively). CONCLUSION: The extent of microcalcifications on mammography after NAC did not correlate with the extent of residual cancer in 38.5% of women. Regardless of the extent of microcalcifications, residual tumour extent on MRI after NAC and molecular subtype could be an accurate tool in evaluating residual cancer after NAC.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/diagnóstico , Mama/diagnóstico por imagem , Calcinose/diagnóstico , Mamografia/métodos , Cuidados Pré-Operatórios/métodos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante
20.
Neoplasma ; 67(2): 259-266, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31777263

RESUMO

Nasopharyngeal carcinoma (NPC) is a rare form of the head and neck cancer of the epithelial lining of the nasopharynx and exhibits the highest metastatic rate among head and neck cancers. Underlying mechanisms of metastasis remain largely unknown. Here, we explored whether Notch1 affects the invasion and metastasis of NPC cells. In vitro migration and invasion capacities were evaluated after the knockdown of Notch1 expression in NPC cells. To investigate the role of Notch1 in in vivo metastasis, we examined the metastatic ability to the lungs following administration of cancer cells via mouse tail vein. The expression of epithelial-mesenchymal transition (EMT) markers associated with Notch1-mediated metastasis was investigated, and their roles in metastasis and relationship with Notch1 expression were investigated. Suppression of Notch1 expression increased the ability of NPC cells to invade Matrigel in vitro. Knockdown of Notch1 expression in NPC cells resulted in extensive lung metastasis in a mouse model and increased the mRNA expression of Slug in NPC cells. Slug-specific RNA interference resulted in the loss of the metastatic and invasion capacities in Notch1-suppressed NPC cells. These findings show that Notch1 has a significant suppressive role in the regulation of metastasis in NPCs, suggestive of its prudent use in clinical trials.


Assuntos
Neoplasias Pulmonares/secundário , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/patologia , Receptor Notch1/genética , Fatores de Transcrição da Família Snail/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Camundongos , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/genética , Invasividade Neoplásica , Metástase Neoplásica , Interferência de RNA
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