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1.
Nanomaterials (Basel) ; 14(2)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38251172

RESUMO

This study investigated the effect of temperature on the aspect-ratio etching of SiO2 in CF4/H2/Ar plasma using patterned samples of a 200 nm trench in a low-temperature reactive-ion etching system. Lower temperatures resulted in higher etch rates and aspect ratios for SiO2. However, the plasma property was constant with the chuck temperature, indicated by the line intensity ratio from optical emission spectroscopy monitoring of the plasma. The variables obtained from the characterization of the etched profile for the 200 nm trench after etching were analyzed as a function of temperature. A reduction in the necking ratio affected the etch rate and aspect ratio of SiO2. The etching mechanism of the aspect ratio etching of SiO2 was discussed based on the results of the surface composition at necking via energy-dispersive X-ray spectroscopy with temperature. The results suggested that the neutral species reaching the etch front of SiO2 had a low sticking coefficient. The bowing ratio decreased with lowering temperature, indicating the presence of directional ions during etching. Therefore, a lower temperature for the aspect ratio etching of SiO2 could achieve a faster etch rate and a higher aspect ratio of SiO2 via the reduction of necking than higher temperatures.

2.
J Neurosci Res ; 102(1): e25271, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38284837

RESUMO

Similar to the human brain, Drosophila glia may well be divided into several subtypes that each carries out specific functions. Glial GPCRs play key roles in crosstalk between neurons and glia. Drosophila Lgr4 (dLgr4) is a human relaxin receptor homolog involved in angiogenesis, cardiovascular regulation, collagen remodeling, and wound healing. A recent study suggests that ilp7 might be the ligand for Lgr4 and regulates escape behavior of Drosophila larvae. Here we demonstrate that Drosophila Lgr4 expression in glial cells, not neurons, is necessary for early development, adult behavior, and lifespan. Reducing the Lgr4 level in glial cells disrupts Drosophila development, while knocking down other LGR family members in glia has no impact. Adult-specific knockdown of Lgr4 in glia but not neurons reduce locomotion, male reproductive success, and animal longevity. The investigation of how glial expression of Lgr4 contributes to this behavioral alteration will increase our understanding of how insulin signaling via glia selectively modulates neuronal activity and behavior.


Assuntos
Proteínas de Drosophila , Drosophila , Neuroglia , Receptores Acoplados a Proteínas G , Animais , Masculino , Encéfalo , Neurônios , Receptores de Neuropeptídeos , Receptores Acoplados a Proteínas G/genética , Proteínas de Drosophila/genética
3.
J Microbiol Biotechnol ; 33(11): 1495-1505, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37482801

RESUMO

The western honeybee Apis mellifera L., a vital crop pollinator and producer of honey and royal jelly, faces numerous threats including diseases, chemicals, and mite infestations, causing widespread concern. While extensive research has explored the link between gut microbiota and their hosts. However, the impact of Varroa destructor infestation remains understudied. In this study, we employed massive parallel amplicon sequencing assays to examine the diversity and structure of gut microbial communities in adult bee groups, comparing healthy (NG) and Varroa-infested (VG) samples. Additionally, we analyzed Varroa-infested hives to assess the whole body of larvae. Our results indicated a notable prevalence of the genus Bombella in larvae and the genera Gillamella, unidentified Lactobacillaceae, and Snodgrassella in adult bees. However, no statistically significant difference was observed between NG and VG. Furthermore, our PICRUSt analysis demonstrated distinct KEGG classification patterns between larval and adult bee groups, with larvae displaying a higher abundance of genes involved in cofactor and vitamin production. Notably, despite the complex nature of the honeybee bacterial community, methanogens were found to be present in low abundance in the honeybee microbiota.


Assuntos
Microbioma Gastrointestinal , Microbiota , Infestações por Ácaros , Varroidae , Animais , Abelhas , Infestações por Ácaros/epidemiologia , Larva , Microbiota/genética , Microbioma Gastrointestinal/genética
4.
PLoS Genet ; 19(5): e1010753, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37216404

RESUMO

Males have finite resources to spend on reproduction. Thus, males rely on a 'time investment strategy' to maximize their reproductive success. For example, male Drosophila melanogaster extends their mating duration when surrounded by conditions enriched with rivals. Here we report a different form of behavioral plasticity whereby male fruit flies exhibit a shortened duration of mating when they are sexually experienced; we refer to this plasticity as 'shorter-mating-duration (SMD)'. SMD is a plastic behavior and requires sexually dimorphic taste neurons. We identified several neurons in the male foreleg and midleg that express specific sugar and pheromone receptors. Using a cost-benefit model and behavioral experiments, we further show that SMD behavior exhibits adaptive behavioral plasticity in male flies. Thus, our study delineates the molecular and cellular basis of the sensory inputs required for SMD; this represents a plastic interval timing behavior that could serve as a model system to study how multisensory inputs converge to modify interval timing behavior for improved adaptation.


Assuntos
Drosophila melanogaster , Feromônios , Animais , Masculino , Drosophila melanogaster/genética , Paladar , Comportamento Sexual Animal/fisiologia , Reprodução , Drosophila
5.
Br J Hosp Med (Lond) ; 84(1): 1-5, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36708343

RESUMO

Vertebral osteomyelitis is a condition that predominantly affects older men with chronic comorbidities, such as diabetes, renal and hepatic failure, or immunosuppression. Symptoms develop insidiously and a high index of suspicion is required to diagnose the condition; this is achieved through serological testing and imaging. The mainstay of treatment is long-term antibiotic therapy, lasting a minimum of 6 weeks; however, surgical debridement with stabilisation is required when conservative treatment is proving ineffective and infection progresses. It is critically important that sufficient treatment is provided for those experiencing vertebral osteomyelitis, as not doing so could lead to severe neurological compromise and death.


Assuntos
Discite , Osteomielite , Masculino , Humanos , Adulto , Idoso , Antibacterianos/uso terapêutico , Osteomielite/diagnóstico , Osteomielite/terapia
6.
Int Orthop ; 47(2): 573-584, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36496548

RESUMO

INTRODUCTION: Accurate implant positioning, tailored to the phenotype and unique biomechanics of each patient is the single most important objective in achieving stability in THA and maximise range of motion. The spine-pelvis-hip construct functions as a single unit adapting to postural changes. It is widely accepted in the literature that no universaltarget exists and variations in spinopelvic mobility mandate adjustments to the surgical plan; thus bringing to the fore the concept of personalised, functional component positioning. METHODS: This manuscript aims to outline the challenges posed by spinopelvic imbalance and present a reproducible, stepwise approach to achieve functional-component positioning. We also present the one-year functional outcomes and Patient Reported Outcome Measures of a prospective cohort operated with this technique. RESULTS AND CONCLUSION: Robotic-arm assisted Total Hip Arthroplasty has facilitated enhanced planning based on the patient's phenotype and evidence suggests it results in more reproducible and accurate implant positioning. Preservation of offset, avoiding leg-length discrepancy, accurate restoration of the centre of rotation and accomplishing the combinedversion target are very important parameters in Total Hip Arthroplasty that affect post-operative implant longevity, patient satisfaction and clinical outcomes.


Assuntos
Artroplastia de Quadril , Procedimentos Cirúrgicos Robóticos , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/métodos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Procedimentos Cirúrgicos Robóticos/métodos , Estudos Prospectivos , Satisfação do Paciente , Pelve
7.
Medicina (Kaunas) ; 58(11)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36363573

RESUMO

Robotic-arm-assisted total hip arthroplasty (RoTHA) offers the opportunity to improve the implant positioning and restoration of native hip mechanics. The concept of individualised, functional implant positioning and how it relates to spinopelvic imbalance is an important yet rather novel consideration in THA. There is mounting evidence that a significant percentage of dislocations occur within the perceived "safe zones"; hence, in the challenging subset of patients with a stiff spinopelvic construct, it is imperative to employ individualised component positioning based on the patients' phenotype. Restoring the native centre of rotation, preserving offset, achieving the desired combined anteversion and avoiding leg length inequality are all very important surgeon-controlled variables that have been shown to be associated with postoperative outcomes. The latest version of the software has a feature of virtual range of motion (VROM), which preoperatively identifies potential dynamic causes of impingement that can cause instability. This review presents the workflow of RoTHA, especially focusing on pragmatic solutions to tackle the challenge of spinopelvic imbalance. Furthermore, it presents an overview of the existing evidence concerning RoTHA and touches upon future direction.


Assuntos
Artroplastia de Quadril , Procedimentos Cirúrgicos Robóticos , Fluxo de Trabalho , Braço , Amplitude de Movimento Articular
8.
Rev Sci Instrum ; 93(10): 103521, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319369

RESUMO

A laboratory-scale experiment was conducted to reproduce plasma with properties similar to re-entry plasma and measure the plasma density using a microwave reflectometer system. To reproduce a similar re-entry plasma, a high-temperature refractory anode vacuum arc plasma method was used among arc plasma discharge methods, and arc plasma having high temperature, high speed, and high-density plasma characteristics was discharged inside a vacuum chamber. A hot refractory anode made of tungsten was used to show high-temperature plasma characteristics, and high-density plasma characteristics were demonstrated using re-evaporation around the anode. In addition, high-speed plasma characteristics were exhibited using a brass cathode. This kind of arc plasma discharge has a high temperature and is characterized by high fluctuation. It was determined that a microwave reflectometer system with good spatial resolution and non-invasiveness would be suitable to measure plasma with these characteristics. The reflection coefficient was measured using a reflector system by comparing the voltage between the traveling wave applied to the plasma and the reflected wave reflected by the plasma, and the technique of analyzing the plasma density using the difference between these reflection coefficients was used. In this study, the plasma density according to the pressure change was typically measured as 1012-1013 cm-3, which showed a similar tendency to the result of measuring the actual re-entry plasma density.

9.
Gels ; 8(2)2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35200458

RESUMO

Carbon nanotubes (CNTs), having either metallic or semiconducting properties depending on their chirality, are advanced materials that can be used for different devices and materials (e.g., fuel cells, transistors, solar cells, reinforced materials, and medical materials) due to their excellent electrical conductivity, mechanical strength, and thermal conductivity. Single-walled CNTs (SWNTs) have received special attention due to their outstanding electrical and optical properties; however, the inability to selectively synthesize specific types of CNTs has been a major obstacle for their commercialization. Therefore, researchers have studied different methods for the separation of SWNTs based on their electrical and optical properties. Gel chromatography methods enable the large-scale separation of metallic/semiconducting (m/s) SWNTs and single-chirality SWNTs with specific bandgaps. The core principle of gel chromatography-based SWNT separation is the interaction between the SWNTs and gels, which depends on the unique electrical properties of the former. Controlled pore glass, silica gel, agarose-based gel, and allyl dextran-based gel have been exploited as mediums for gel chromatography. In this paper, the interaction between SWNTs and gels and the different gel chromatography-based SWNT separation technologies are introduced. This paper can serve as a reference for researchers who plan to separate SWNTs with gel chromatography.

10.
Cureus ; 13(11): e19374, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34925980

RESUMO

Pediatric ankle and wrist fractures are very common injuries encountered by orthopedic departments. The National Institute of Clinical Excellence has published guidelines that should be adhered to when treating these common fractures. This audit included 560 patients that have sustained wrist and ankle fractures between 2008 and 2019 at Queen Elizabeth Hospital Burton (QHB) that required surgical management. The results show that 99.7% (478/479) wrist fractures and 70.8% (57/81) of ankle fractures received surgical management within the timeframe outlined by NICE. This audit has shown that QHB has been successfully treating wrist fractures within the guidelines set by NICE but has failed to meet the standards for ankle fractures.

11.
Medicina (Kaunas) ; 57(8)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34440950

RESUMO

Background and Objectives: The current options for acute pain control of vertebral compression fracture include hard brace, vertebroplasty, early surgery, and analgesic injection. We hypothesize that the gray ramus communicans nerve block (GRNB) controls the acute pain experienced during vertebral compression fractures. This study assessed the time course of pain control after injection and evaluated the risk factors affecting pain control failure. Materials and methods: Sixty-three patients (24 male, 66.19 ± 15.17 y) with a thoracolumbar vertebral fracture at the T10-L5 spine, who presented to our hospital from November 2018 to October 2019, were included in this retrospective cohort study. GRNB was performed within 1 week of the trauma. The patients were followed up on days 3, 14, 30, 90, and 180 and assessed with the serial visual analog scale (VAS, resting and motion), Oswestry Low Back Disability (ODI) questionnaire, and Roland-Morris Disability Questionnaire (RDQ). The failure group was defined by the need for an additional block or cement injection after a single GRNB. The failure group's risk factors, such as body mass index, initial thoracolumbar injury classification and severity score, Kummel's disease, age, bone marrow density (BMD), and underlying disease, were analyzed. Results: The motion VAS score improved from preoperative to three months post-procedure, but the resting VAS was affected by the procedure for only three days. The quality of life index improved at postoperative six months. A lower BMD was the only risk that affected treatment failure in the logistic regression analysis (p = 0.0038). Conclusion: The effect of GRNB was maintained even at three months after trauma based on motion VAS results. The only risk factor identified for GRNB failure was lower BMD.


Assuntos
Dor Aguda , Fraturas por Compressão , Bloqueio Nervoso , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Fraturas por Compressão/complicações , Fraturas por Compressão/cirurgia , Humanos , Masculino , Fraturas por Osteoporose/cirurgia , Qualidade de Vida , Estudos Retrospectivos , Fraturas da Coluna Vertebral/complicações , Fraturas da Coluna Vertebral/cirurgia , Resultado do Tratamento
12.
Br J Hosp Med (Lond) ; 82(7): 1-6, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34338018

RESUMO

Lateral condyle fracture of the humerus is the second most common paediatric elbow fracture and is often missed, which can result in severe consequences including malunion, growth arrest and tardy ulnar nerve palsy. The difficulty in managing this fracture stems from a lack of awareness and the often subtle findings on radiographs. Patients can also present with quite vague symptoms; clinicians who do not have a high index of suspicion may not investigate beyond the initial clinical assessment and could miss vital cues. This article provides a guide to managing this common paediatric fracture, from initial presentation to definitive treatment, and discusses the complications that can ensue if managed incorrectly.


Assuntos
Articulação do Cotovelo , Fraturas do Úmero , Criança , Articulação do Cotovelo/diagnóstico por imagem , Fixação Interna de Fraturas , Humanos , Fraturas do Úmero/diagnóstico por imagem , Fraturas do Úmero/terapia , Úmero , Radiografia
13.
Materials (Basel) ; 14(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199585

RESUMO

The use of NF3 is significantly increasing every year. However, NF3 is a greenhouse gas with a very high global warming potential. Therefore, the development of a material to replace NF3 is required. F3NO is considered a potential replacement to NF3. In this study, the characteristics and cleaning performance of the F3NO plasma to replace the greenhouse gas NF3 were examined. Etching of SiO2 thin films was performed, the DC offset of the plasma of both gases (i.e., NF3 and F3NO) was analyzed, and a residual gas analysis was performed. Based on the analysis results, the characteristics of the F3NO plasma were studied, and the SiO2 etch rates of the NF3 and F3NO plasmas were compared. The results show that the etch rates of the two gases have a difference of 95% on average, and therefore, the cleaning performance of the F3NO plasma was demonstrated, and the potential benefit of replacing NF3 with F3NO was confirmed.

14.
Acta Biomed ; 92(3): e2021200, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34212906

RESUMO

BACKGROUND AND AIM OF THE WORK: In the best of our knowledge there is not yet in the literature a measurement able to assess post reduction stability of distal radius fractures. AIM: to study the relationship between our newly introduced Pacetti's line, anatomical reduction of DRFs and post-reduction stability of fractures. METHODS: Patients/Participants: 230 patients (122men, 108women) who sustained a dorsally displaced distal radius fracture. Close reduction procedures attempted; below elbow cast applied. FOLLOW-UP: Pacetti's line used on true AP and lateral view xrays after reduction and casting (T0) and at 7-14 days (T1-T2). MAIN OUTCOME MEASUREMENTS: Assessment and prediction of early displacement of DRFs. RESULTS: The Pacetti's line intersected the lunate bone in 162 cases (70.4%) after anatomical reduction, of which 20.4% (N=33) lost anatomical reduction. Cramer's V test: significant relationship between transition of Pacetti's line through the semilunar bone and stability of anatomical reduction at T0 follow-up (p<0.001, Cramer's value=0.83). The Pacetti's line intersected the lunate bone in 119 cases (51.7%) at 7-14 days follow-up. None of patients lost anatomical reduction. Cramer's V test: significant relationship between transition of Pacetti's line through the semilunar bone and stability anatomical reduction at T1 and T2 follow-up (p<0.001, Cramer's value=0.73). CONCLUSIONS: We strongly recommend the use of the Pacetti's line as it seems to provide reliable prediction of further fracture displacement and consequently of definitive management. The Pacetti's line seems to represent a very useful tool providing simple, feasible, efficient and reliable information on DRFs characteristics and natural course.


Assuntos
Osso Semilunar , Fraturas do Rádio , Placas Ósseas , Moldes Cirúrgicos , Fixação Interna de Fraturas , Humanos , Radiografia , Fraturas do Rádio/diagnóstico por imagem
15.
Int J Med Robot ; 17(6): e2308, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34288356

RESUMO

BACKGROUND: The purpose of this study was to compare total blood loss and the risk of receiving a blood transfusion in robotic-assisted total knee arthroplasty (TKA) and unicompartmental knee arthroplasty (UKA) against conventional jig-based techniques. METHODS: Robotic TKA (n = 50) and UKA (n = 50) patients were matched to contemporary controls for TKA (n = 50) and UKA (n = 50) and retrospectively analysed. RESULTS: Robotic TKA patients experienced 23.7% less blood loss compared to conventional TKA patients (911.0 ml vs 1193.7 ml, p < 0.01), and were associated with an 83% relative risk reduction of receiving a transfusion (2% of patients vs 12%, p = 0.02). Robotic UKA patients did not demonstrate less blood loss compared to corresponding controls (821.7 ml vs 854.7 ml, p = 0.69). Both UKA groups received no transfusions. CONCLUSIONS: Robotic surgical systems in TKA reduces blood loss and lowers the risk of requiring a blood transfusion. In UKA, robotic-assisted arthroplasty did not reduce blood loss compared to conventional arthroplasty.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho , Procedimentos Cirúrgicos Robóticos , Artroplastia do Joelho/efeitos adversos , Transfusão de Sangue , Humanos , Articulação do Joelho/cirurgia , Osteoartrite do Joelho/cirurgia , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Resultado do Tratamento
16.
Cureus ; 13(11): e20039, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34993025

RESUMO

Chronic diarrhoea is a common condition that affects up to 5% of the population which heavily affects the quality of life for the patient. The British Society of Gastroenterology guidelines recommend that for those who suffer with chronic diarrhoea, a colonoscopy with a biopsy is recommended to exclude microscopic colitis. This retrospective audit included 147 patients who received endoscopic procedures in 2019 at Walsall Manor Hospital for chronic diarrhoea. The results show that a total of £56,797 was incurred through endoscopic and histological investigation with four patients (2.6%) diagnosed with microscopic colitis. Given the lack of diagnostic yield, there is room for advancement in the current guidelines for managing persistent diarrhoea.

17.
Nat Commun ; 11(1): 3783, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32728021

RESUMO

Current thermochemical methods to generate H2 include gasification and steam reforming of coal and natural gas, in which anthropogenic CO2 emission is inevitable. If biomass is used as a source of H2, the process can be considered carbon-neutral. Seaweeds are among the less studied types of biomass with great potential because they do not require freshwater. Unfortunately, reaction pathways to thermochemically convert salty and wet biomass into H2 are limited. In this study, a catalytic alkaline thermal treatment of brown seaweed is investigated to produce high purity H2 with substantially suppressed CO2 formation making the overall biomass conversion not only carbon-neutral but also potentially carbon-negative. High-purity 69.69 mmol-H2/(dry-ash-free)g-brown seaweed is produced with a conversion as high as 71%. The hydroxide is involved in both H2 production and in situ CO2 capture, while the Ni/ZrO2 catalyst enhanced the secondary H2 formation via steam methane reforming and water-gas shift reactions.


Assuntos
Carbono/isolamento & purificação , Hidrogênio/isolamento & purificação , Energia Renovável , Alga Marinha/química , Álcalis/química , Biomassa , Carbono/química , Catálise , Temperatura Alta , Hidrogênio/química , Vapor
18.
Nanomaterials (Basel) ; 10(2)2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32102300

RESUMO

A hybrid film consisting of zinc oxide nanoparticles (ZnO NPs) and carbon nanotubes (CNTs) is formed on a glass substrate using a simple and swift spin coating process for the use in ultraviolet photodetectors (UV PDs). The incorporation of various types of CNTs into ZnO NPs (ZnO@CNT) enhances the performance of UV PDs with respect to sensitivity, photoresponse, and long-term operation stability when compared with pristine ZnO NP films. In particular, the introduction of single-walled CNTs (SWNTs) exhibits a superior performance when compared with the multiwalled CNTs (MWNTs) because SWNTs can not only facilitate the stability of free electrons generated by the O2 desorption on ZnO under UV irradiation owing to the built-in potential between ZnO and SWNT heterojunctions, but also allow facile and efficient transport pathways for electrons through SWNTs with high aspect ratio and low defect density. Furthermore, among the various SWNTs (arc-discharged (A-SWNT), Hipco (H-SWNT), and CoMoCat (C-SWNT) SWNTs), we demonstrate the ZnO@A-SWNT hybrid film exhibits the best performance because of higher conductivity and aspect ratio in A-SWNTs when compared with those of other types of SWNTs. At the optimized conditions for the ZnO@A-SWNT film (ratio of A-SWNTs and ZnO NPs and electrode distance), ZnO@A-SWNT displays a sensitivity of 4.9 × 103 % with an on/off current ratio of ~104 at the bias of 2 V under the UV wavelength of 365 nm (0.47 mW/cm2). In addition, the stability in long-term operation and photoresponse time are significantly improved by the introduction of A-SWNTs into the ZnO NP film when compared with the bare ZnO NPs film.

19.
J Clin Pharmacol ; 60(2): 264-273, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31465127

RESUMO

Pathologic roles of interleukin (IL)-2, IL-9, and IL-15, have been implicated in multiple T-cell malignancies and autoimmune diseases. BNZ-1 is a selective and simultaneous inhibitor of IL-2, IL-9, and IL-15, which targets the common gamma chain signaling receptor subunit. In this first-in-human study, 18 healthy adults (n = 3/cohort) received an intravenous dose of 0.2, 0.4, 0.8, 1.6, 3.2, or 6.4 mg/kg infused over ≤5 minutes on day 1 and were followed for 30 days for safety and pharmacokinetic/pharmacodynamic sample collection. No dose-limiting toxicities, infusion reactions, or serious or severe treatment-emergent adverse events were observed. Headache was the only treatment-emergent adverse event in >1 subject (n = 3). Peak and total BNZ-1 exposure was generally dose proportional, with a terminal elimination half-life of ∼5 days. Pharmacodynamic effects of BNZ-1 on regulatory T cells (Tregs, IL-2), natural killer (NK) cells (IL-15) and CD8 central memory T cells (Tcm, IL-15) were measured by flow cytometry and used to demonstrate target engagement. For Tregs, 0.2 mg/kg was an inactive dose, while a maximum ∼50% to 60% decrease from baseline was observed on day 4 after doses of 0.4 to 1.6 mg/kg, and higher doses produced an 80% to 93% decrease from baseline on day 15. Similar pharmacodynamic trends were observed for natural killer cells and CD8 Tcm, although decreases in CD8 Tcm were more prolonged. These subpopulations returned to/toward baseline by day 31. T cells (total, CD4, and CD8), B cells, and monocytes were unchanged throughout. These preliminary results suggest that BNZ-1 safely and selectively inhibits IL-2 and IL-15, which results in robust, reversible immunomodulation.


Assuntos
Subunidade gama Comum de Receptores de Interleucina/metabolismo , Interleucina-15/antagonistas & inibidores , Interleucina-2/antagonistas & inibidores , Interleucina-9/antagonistas & inibidores , Peptídeos/efeitos adversos , Peptídeos/farmacocinética , Adulto , Linfócitos B/efeitos dos fármacos , Feminino , Voluntários Saudáveis , Humanos , Infusões Intravenosas , Células Matadoras Naturais/efeitos dos fármacos , Masculino , Peptídeos/administração & dosagem , Linfócitos T/efeitos dos fármacos
20.
J Chem Phys ; 151(14): 144704, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31615236

RESUMO

Colloidal InP quantum dots (QDs) have attracted a surge of interest as environmentally friendly light-emitters in downconversion liquid crystal displays and light-emitting diodes (LEDs). A ZnS shell on InP-based core QDs has helped achieve high photoluminescence (PL) quantum yield (QY) and stability. Yet, due to the difficulty in the growth of a thick ZnS shell without crystalline defects, InP-based core/shell QDs show inferior stability against QY drop compared to Cd chalcogenide precedents, e.g., CdSe/CdS core/thick-shell QDs. In this work, we demonstrate the synthesis of InP-based core/shell QDs coated with an Al-doped ZnS outer shell. QDs with an Al-doped shell exhibit remarkable improvement in thermal and air stability even when the shell thickness is below 2 nm, while the absorption and PL spectra, size, and crystal structure are nearly the same as the case of QDs with a pristine ZnS shell. X-ray photoelectron spectroscopy reveals that Al3+ in Al-doped QDs forms an Al-oxide layer at elevated temperature under ambient atmosphere. The as-formed Al-oxide layer blocks the access of external oxidative species penetrating into QDs and prevents QDs from oxidative degradation. We also trace the chemical pathway of the incorporation of Al3+ into ZnS lattice during the shell growth. Furthermore, we fabricate QD-LEDs using Al-doped and undoped QDs and compare the optoelectronic characteristics and stability.

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