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It is known that glow discharges with a water anode inject and form solvated electrons at the plasma-liquid interface, driving a wide variety of reduction reactions. However, in systems with a water cathode, the production and role of solvated electrons are less clear. Here, we present evidence for the direct detection of solvated electrons produced at the interface of an argon plasma and a water cathode via absorption spectroscopy. We further quantify their yield using the dissociative electron attachment of chloroacetate, measuring a yield of 1.04 ± 0.59 electrons per incident ion, corresponding to approximately 100% faradaic efficiency. Additionally, we estimate a yield of 2.09 ± 0.93 hydroxyl radicals per incident ion. Comparison of this yield with other findings in the literature supports that these hydroxyl radicals are likely formed directly in the liquid phase rather than by diffusion from the vapor phase.
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Aqueous-based synthesis is one of the most popular methods to prepare nanoparticles. In these procedures, surfactants are needed to regulate the growth and final particle size. While there are numerous evidence on the decisive role of surfactants, a quantitative description remains elusive. This study develops a theoretical model to correlate the surfactant activities to particle growth. In the model, the "penetrability" of ions within surfactant layer is used to combine surface reaction and adsorption/desorption processes. The penetrability was then directly correlated to surfactant size. The theory was verified by synthesis of iron oxide nanoparticles with series of cationic surfactants. Eight surfactants, with same headgroup and increasing hydrocarbon tail, were employed. The experimental data showed a deterministic correlation between surfactant tails and particle size. The experimental correlation between surfactant length and particle size was predicted by the model. The modeling results verify the role of surfactant as capping agent during particle growth. More importantly, it provides a theoretical framework to control particle size in wet synthesis.
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Potato virus A (PVA) is a plant-infecting RNA virus that produces flexible particles with a high aspect ratio. PVA has been investigated extensively for its infection biology, however, its potential to serve as a nanopatterning platform remains unexplored. Here, we study the liquid crystal and interfacial self-assembly behavior of PVA particles. Furthermore, we generate nanopatterned surfaces using self-assembled PVA particles through three different coating techniques: drop-casting, drop-top deposition and flow-coating. The liquid crystal phase of PVA solution visualized by polarized optical microscopy revealed a chiral nematic phase in water, while in pH 8 buffer it produced a nematic phase. This allowed us to produce thin films with either randomly or anisotropically oriented cylindrical nanopatterns using drop-top and flow-coating methods. Overall, this study explores the self-assembly process of PVA in different conditions, establishing a starting point for PVA self-assembly research and contributing a virus-assisted fabrication technique for nanopatterned surfaces.
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Potyvirus , MicroscopíaRESUMEN
High-energy tibial fractures often present with associated soft tissue injuries, including neuro-vascular damage, complicating the treatment decision. A 33-year-old male presented with Gustilo Anderson type IIIA fracture of the left distal tibia and fibula with associated closed calcaneus fracture and tibial nerve transection. Amputation was discussed, but the decision was made for limb salvage with nerve allograft. The patient displayed satisfactory functional recovery at 29 months postoperatively without need for major revision, grafting, arthrodesis, or amputation. This case report provides an example of successful limb salvage utilizing tibial nerve allograft in a complex high-energy lower extremity injury. Level of Evidence: IV.
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Fracturas Abiertas , Fracturas de la Tibia , Lesiones del Sistema Vascular , Masculino , Humanos , Adulto , Recuperación del Miembro/efectos adversos , Fracturas de la Tibia/diagnóstico por imagen , Fracturas de la Tibia/cirugía , Tibia/cirugía , Peroné/cirugía , Peroné/lesiones , Lesiones del Sistema Vascular/cirugía , Amputación Quirúrgica , Resultado del Tratamiento , Estudios Retrospectivos , Fracturas Abiertas/cirugía , Fracturas Abiertas/complicacionesRESUMEN
BACKGROUND: Single-port laparoscopic surgery has been described for various colorectal conditions. Here, we report the first 4 single-port laparoscopic sigmoid colostomies for fecal diversion. METHODS: A 1.5-cm-round incision was made on the skin at a previously marked colostomy site. A wound retractor was inserted and an access platform with four 5-mm trocars was attached to the wound retractor. The sigmoid colon was mobilized using electrocautery, laparoscopic scissors, or an advanced bipolar device. A standard Brooke colostomy was created through the initial skin incision. RESULTS: Four elective single-port laparoscopic diverting colostomies were performed. Indications included obstructing colon and rectal cancers and intractable Crohn's proctitis. The average operative time was 73 minutes (range, 53-105), and blood loss was minimal (<50 mL). There were no intraoperative complications. Three of 4 patients received oral analgesia, and one patient received patient-controlled intravenous analgesia postoperatively. The average time to passage of flatus was 1 day. Diet was advanced either on the day of surgery or on postoperative day 1. The length of hospital stay ranged from 0 to 15 days. CONCLUSION: Single-port laparoscopic sigmoid colostomy is an effective technique that allows full intra-abdominal visualization and colonic mobilization while eliminating the need for additional skin incisions other than the colostomy site itself.
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Colon Sigmoide/cirugía , Colostomía/métodos , Enfermedades Gastrointestinales/cirugía , Laparoscopía , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades del Colon/cirugía , Enfermedad de Crohn/cirugía , Femenino , Humanos , Obstrucción Intestinal/cirugía , Masculino , Persona de Mediana Edad , Observación , Proctitis/cirugía , Neoplasias del Recto/cirugía , Resultado del TratamientoRESUMEN
The human liver is enriched in NK cells which are potent effectors of the innate immune system. We have determined that liver NK cells freshly isolated from surgical specimens from patients with hepatic malignancy have less cytolytic activity than autologous blood NK cells. This difference was due to a higher proportion of CD16(-) NK cells in the liver and reduced cytotoxicity by CD16(+) liver NK cells compared with their blood counterparts. CD16(+) liver NK cells had similar expression of activating NK receptors and had similar intracellular granzyme B and perforin content compared with CD16(+) blood NK cells. CD16(+) liver NK cells contained a reduced fraction of cells with inhibitory killer Ig-like receptors specific for self-MHC class I (self-killer Ig-related receptor (KIR)) and an increased fraction of self-KIR(neg)NKG2A(pos) and self-KIR(neg)NKG2A(neg) cells. Using single-cell analysis of intracellular IFN-gamma production and cytotoxicity assays, we determined that CD16(+) liver NK cells expressing self-KIR were more responsive to target cells than those cells that did not express self-KIR molecules. CD16(+) liver NK cells gained cytolytic function when stimulated with IL-2 or cultured with LPS or poly(I:C)-activated autologous liver Kupffer cells. Thus, the human liver contains NK cell subsets which have reduced effector function, but under appropriate inflammatory conditions become potent killers.
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Citotoxicidad Inmunológica , Células Asesinas Naturales/inmunología , Hígado/inmunología , Receptores KIR/análisis , Autoinmunidad , Células Sanguíneas/inmunología , Humanos , Inmunidad Innata , Receptores de IgGRESUMEN
The liver is believed to promote tolerance, which may be beneficial due to its constant exposure to foreign Ags from the portal circulation. Although dendritic cells (DCs) are critical mediators of immune responses, little is known about human liver DCs. We compared freshly purified liver DCs from surgical specimens with autologous blood DCs. Liver and blood DCs were equally immature, but had distinct subset compositions. BDCA-1(+) DCs represented the most prevalent liver DC subset, whereas the majority of peripheral blood DCs were CD16(+). Upon TLR4 ligation, blood DCs secreted multiple proinflammatory cytokines, whereas liver DCs produced substantial amounts of IL-10. Liver DCs induced less proliferation of allogeneic T cells both in a primary MLR and after restimulation. Similarly, Ag-specific CD4(+) T cells were less responsive to restimulation when initially stimulated by autologous liver DCs rather than blood DCs. In addition, liver DCs generated more suppressive CD4(+)CD25(+)FoxP3(+) T regulatory cells and IL-4-producing Th2 cells via an IL-10-dependent mechanism. Our findings are critical to understanding hepatic immunity and demonstrate that human liver DCs promote immunologic hyporesponsiveness that may contribute to hepatic tolerance.
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Células Dendríticas/inmunología , Tolerancia Inmunológica/inmunología , Hígado/inmunología , Activación de Linfocitos/inmunología , Linfocitos T/inmunología , Presentación de Antígeno/inmunología , Citocinas/biosíntesis , Citometría de Flujo , Humanos , Hígado/citología , Prueba de Cultivo Mixto de LinfocitosRESUMEN
Block copolymer (BCP) thin films prepared by dip-coating are increasingly investigated, owing to the many promising application areas, the facility, and the industrial scalability of this technique. Yet, the effect of different dip-coating parameters on BCP nanostructure formation is still underdeveloped and the results of previous literature are limited to a few block copolymers. Here, we study the effect of the withdrawal rate and solvent selectivity on the morphology evolution of dip-coated polystyrene-b-poly(ethylene oxide) thin films by applying a wide range of dip-coating speeds and altering the volume ratio of the tetrahydrofuran-water solvent system. The dip-coated films were characterized using atomic force microscopy and ellipsometry. The nanodomain morphology, its feature sizes, its spanning, and the degree of ordering were investigated with regard to different dip-coating parameters. Notably, we have obtained a hexagonally packed BCP pattern with long-range order without the need for post-annealing processes. Overall, a solid understanding of the parameters affecting the formed surface patterns and their interplay was attained and explained, extending the knowledge of this field to more materials.
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We demonstrate a compact silicon photonic crystal Mach-Zehnder interferometer operating in the self-collimation regime. By tailoring the photonic band structure such as to produce self-collimated beams, it is possible to design beam splitters and mirrors and combine these to a 20 x 20 microm(2) format. With transmission spectroscopy we find a pronounced unidirectional optical output, the output ratio being as high as 25 at the self-collimation wavelength. Furthermore, the self-collimated beams and the unidirectionality are clearly observed in real space using near-field and far-field optical microscopy. Interpretation of the optical data is strongly supported by different types of simulations.
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BACKGROUND: People with Parkinson disease (PD) have difficulty initiating internally generated movements. We have shown that computer-based cognitive training can improve movement initiation. However, little is known about the optimal duration of training. OBJECTIVES: To determine the optimal training duration for computer-based neurorehabilitation of internally represented movement initiation in people with PD. METHODS: Nineteen PD and twenty-one age-matched control participants, ages 50-85 years, were included in analysis of pre- and post-training evaluation and 30 training sessions. Computer training consisted of cued and un-cued movement trials. The presentation of a cue (a combination of numbers on either the right, left or both sides of the screen) indicated that participants should respond by typing the numbers. Successful cued trials were followed by un-cued trials consisting of a green filled circle. Participants re-enter the cued sequence, thus producing an internally represented (IR) movement. The training was adaptive. Outcome measures were reaction time and error rate, and cumulative sum (CUSUM) analysis was used to identify peak training improvement. RESULTS: Participants with PD were divided into impaired (IPD) and unimpaired (UPD) groups, based on mean control group pre-training performance. All three groups showed improved RT and error rates for IR trials; however, the IPD group demonstrated significantly greater improvement in reaction time. Training was most effective in participants with greater disease severity and duration. Peak day of training improvement for the IPD group was 8 days. CONCLUSION: Optimal training duration was relatively short and the IPD group demonstrated the most gain, indicating that cognitive training should be tailored to individual needs.
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Rehabilitación Neurológica/métodos , Enfermedad de Parkinson/rehabilitación , Anciano , Anciano de 80 o más Años , Humanos , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
UNLABELLED: The liver harbors a diversity of cell types that have been reported to stimulate T cells. Although most hepatic dendritic cells are immature, a small population of CD11c(high) conventional dendritic cells (cDCs) exists that expresses high levels of costimulatory molecules. We sought to determine the relative contribution of cDCs to cross-presentation by the liver. In vitro, liver nonparenchymal cells (NPCs) depleted of cDCs induced only minimal proliferation and activation of antigen-specific CD8(+) T cells when loaded with soluble protein antigen. Using a transgenic mouse with the CD11c promoter driving expression of the human diphtheria toxin receptor, we found that selective depletion of cDCs in vivo reduced the number and activation of antigen-specific CD8(+) T cells in the liver after intravenous administration of soluble protein antigen. Adoptive transfer of DCs, but not CD40 stimulation, restored the hepatic T-cell response. CONCLUSION: Our findings indicate that the ability of the liver to effectively cross-present soluble protein to antigen-specific CD8(+) T cells depends primarily on cDCs. Despite costimulation, other resident liver antigen-presenting cells cannot compensate for the absence of cDCs.
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Reactividad Cruzada/fisiología , Células Dendríticas/fisiología , Hígado/inmunología , Linfocitos T/fisiología , Animales , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ovalbúmina , FenotipoRESUMEN
The liver contains a unique repertoire of immune cells and a particular abundance of NK cells. We have found that CD11c defines a distinct subset of NK cells (NK1.1(+)CD3(-)) in the murine liver whose function was currently unknown. In naïve animals, CD11c(+) liver NK cells displayed an activated phenotype and possessed enhanced effector functions when compared with CD11c(-) liver NK cells. During the innate response to adenovirus infection, CD11c(+) NK cells were the more common IFN-gamma-producing NK cells in the liver, demonstrated enhanced lytic capability, and gained a modest degree of APC function. The mechanism of IFN-gamma production in vivo depended on TLR9 ligation as well as IL-12 and -18. Taken together, our findings demonstrate that CD11c(+) NK cells are a unique subset of NK cells in the murine liver that contribute to the defense against adenoviral hepatitis.
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Adenoviridae/patogenicidad , Antígeno CD11c/análisis , Hepatitis Viral Animal/inmunología , Células Asesinas Naturales/fisiología , Células Asesinas Naturales/virología , Infecciones por Adenoviridae/inmunología , Infecciones por Adenoviridae/prevención & control , Animales , Antígeno CD11c/inmunología , Hepatitis Viral Animal/prevención & control , Interferón gamma/biosíntesis , Interleucina-12/inmunología , Interleucina-12/fisiología , Interleucina-18/inmunología , Interleucina-18/fisiología , Hígado/inmunología , Hígado/virología , Ratones , Receptor Toll-Like 9/fisiologíaRESUMEN
The primary objective of the present study is to investigate the possible effects of ultrasonication time on stability and thermal conductivity of MWCNT-water nanofluid. The samples have been prepared in three different solid concentrations of 0.1, 0.3, and 0.5â¯vol.% applying different ultrasonication times, ranging from 10 to 80â¯min. The stability of the samples has been investigated over 30â¯days after preparation by conducting zeta potential analysis and visual observation. It is found that increasing the ultrasonication time until 60â¯min results in enhancing the stability of the samples in all the solid concentrations while prolonging the ultrasonication time leads to deteriorating the stability. The thermal conductivity of the samples has been experimentally measured over different temperatures ranging from 25 to 60⯰C, and it is found that increasing the solid concentration and temperature results in enhancing the thermal conductivity. Moreover, the effects of ultrasonication time on thermal conductivity have also been studied, and it is found that increasing the ultrasonication time leads to a gentle enhancement in thermal conductivity. The maximum conductivity was achieved by applying 60â¯min ultrasonication. Thus, it is concluded that 60â¯min ultrasonication is the optimum time in which the thermal conductivity and stability reached their highest point.
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The main purpose of the present paper is to improve the performance of the adaptive neuro-fuzzy inference system (ANFIS) in predicting the thermophysical properties of Al2O3-MWCNT/thermal oil hybrid nanofluid through mixing using metaheuristic optimization techniques. A literature survey showed that the use of an artificial neural network (ANN) is the most widely used method, although there are other methods that showed better performance. Moreover, it was found in the literature that artificial intelligence methods have been widely used for predicting the thermal conductivity of nanofluids. Thus, in the present study, genetic algorithms (GAs) and particle swarm optimization (PSO) have been utilized to search and determine the antecedent and consequent parameters of the ANFIS model. Solid concentration and temperature were considered as input variables, and thermal conductivity, dynamic viscosity, heat transfer performance, and pumping power in both the internal laminar and turbulent flow regimes were the outputs. In order to evaluate and compare the performance of the models, two statistical indices of root mean square error (RMSE) and determination coefficient (R) were utilized. Based on the results, both of the models are able to predict the thermophysical properties appropriately. However, the ANFIS-PSO model had a better performance than the ANFIS-GA model. Finally, the studied thermophysical properties were developed by the trained ANFIS-PSO model.
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Whether a freshly isolated immune cell can be equipped with both natural killing and antigen-presenting cell (APC) function has recently become controversial in mice. We sought to probe the existence of a candidate human cell with these properties by searching for cells in healthy subjects that co-express APC surface molecules and NK cell receptors. We have found that CD3(-)CD14(-)CD19(-) mononuclear cells of human blood, spleen, liver, and lymph nodes contain two distinct populations of cells that co-express HLA-DR (DR) and CD56. Circulating CD56(+) cells expressing high levels of DR were phenotypically and functionally similar to conventional CD56(-)dendritic cells (DC). Furthermore, we demonstrate here that a separate cohort of CD56(+) cells that express low levels of DR are NK cells that possess dual function as potent killers endowed with weak APC function.
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Presentación de Antígeno , Citotoxicidad Inmunológica , Células Dendríticas/inmunología , Células Asesinas Naturales/inmunología , Antígeno CD56/análisis , Antígeno CD56/metabolismo , Separación Celular , Células Dendríticas/metabolismo , Antígenos HLA-DR/análisis , Humanos , Células Asesinas Naturales/metabolismo , Subgrupos Linfocitarios/inmunologíaRESUMEN
INTRODUCTION: It is common for men to develop erectile dysfunction after radical prostatectomy. The anatomy of the rat allows the cavernous nerve (CN) to be identified, dissected, and injured in a controlled fashion. Therefore, bilateral CN injury (BCNI) in the rat model is routinely used to study post-prostatectomy erectile dysfunction. AIM: To compare and contrast the available literature on pharmacologic intervention after BCNI in the rat. METHODS: A literature search was performed on PubMed for cavernous nerve and injury and erectile dysfunction and rat. Only articles with BCNI and pharmacologic intervention that could be grouped into categories of immune modulation, growth factor therapy, receptor kinase inhibition, phosphodiesterase type 5 inhibition, and anti-inflammatory and antifibrotic interventions were included. MAIN OUTCOME MEASURES: To assess outcomes of pharmaceutical intervention on erectile function recovery after BCNI in the rat model. The ratio of maximum intracavernous pressure to mean arterial pressure was the main outcome measure chosen for this analysis. RESULTS: All interventions improved erectile function recovery after BCNI based on the ratio of maximum intracavernous pressure to mean arterial pressure results. Additional end-point analysis examined the corpus cavernosa and/or the major pelvic ganglion and CN. There was extreme heterogeneity within the literature, making accurate comparisons between crush injury and therapeutic interventions difficult. CONCLUSIONS: BCNI in the rat is the accepted animal model used to study nerve-sparing post-prostatectomy erectile dysfunction. However, an important limitation is extreme variability. Efforts should be made to decrease this variability and increase the translational utility toward clinical trials in humans. Haney NM, Nguyen HMT, Honda M, et al. Bilateral Cavernous Nerve Crush Injury in the Rat Model: A Comparative Review of Pharmacologic Interventions. Sex Med Rev 2018;6:234-241.
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Modelos Animales de Enfermedad , Disfunción Eréctil , Traumatismos de los Nervios Periféricos , Prostatectomía/efectos adversos , Animales , Disfunción Eréctil/tratamiento farmacológico , Disfunción Eréctil/etiología , Masculino , Traumatismos de los Nervios Periféricos/tratamiento farmacológico , Traumatismos de los Nervios Periféricos/etiología , Ratas , Agentes Urológicos/uso terapéuticoRESUMEN
BACKGROUND: Historically, the lateral extensile approach for calcaneal fracture osteosynthesis has had relatively high rates of wound healing problems. The vascular territory (angiosome) of the lateral foot is now known to be dependent upon the lateral calcaneal branch of the peroneal artery (LCBP artery). We postulated that patency of the LCBP artery may have a profound positive impact on incisional wound healing for calcaneal open reduction and internal fixation (ORIF). METHODS: Ninety consecutive calcaneal fractures that met operative criteria were preoperatively evaluated for the presence of a Doppler signal in the LCBP artery and were followed for the development of wound healing problems. RESULTS: Among these 90 fractures, 85 had a positive preoperative Doppler signal along the course of the LCBP artery (94%) and 5 had no Doppler signal (6%). All patients underwent ORIF via a lateral extensile approach. Overall, incisional wound healing problems occurred in 6 of 90 calcaneal incisions (6.5%). All 5 feet that exhibited an absent Doppler signal in the LCPB artery developed an incisional wound healing complication (5/6, approximately 83%): 2 large apical wounds and 3 major dehiscence/slough. However, among the 84 feet that possessed a positive preoperative Doppler signal in the LCBP artery, there was only 1 (1/84, approximately 1%) incisional wound healing problem (P < .0001, Fischer's exact test). Smokers with a positive Doppler signal in the LCBP artery did not develop a wound healing complication. CONCLUSIONS: This study suggests a strong link to low incisional wound healing complications for the lateral extensile approach to the calcaneus when a preoperative Doppler signal is present in the LCBP artery. We believe this simple examination should be routinely performed prior to calcaneal ORIF. LEVEL OF EVIDENCE: Level III, comparative case series.
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Calcáneo/irrigación sanguínea , Calcáneo/cirugía , Fijación Interna de Fracturas/métodos , Fracturas Óseas/cirugía , Cicatrización de Heridas/fisiología , Adolescente , Adulto , Anciano , Calcáneo/lesiones , Femenino , Fracturas Óseas/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento , Ultrasonografía Doppler , Grado de Desobstrucción VascularRESUMEN
The high rate of mortality in patients with sepsis results from an inappropriately amplified systemic inflammatory response to infection. Toll-like receptors (TLRs) are important for the activation of innate immunity against microbial pathogens. We demonstrate a critical role of TLR9 in the dysregulated immune response and death associated with sepsis. Compared with wild-type (WT) mice, TLR9(-/-) mice exhibited lower serum inflammatory cytokine levels, higher bacterial clearance, and greater survival after experimental peritonitis induced by cecal ligation and puncture (CLP). Protection of TLR9(-/-) mice after CLP was associated with a greater number of peritoneal dendritic cells (DCs) and granulocytes than in WT controls. Adoptive transfer of TLR9(-/-) DCs was sufficient to protect WT mice from CLP and increased the influx of peritoneal granulocytes. Subsequent experiments with a depleting antibody revealed that granulocytes were required for survival in TLR9(-/-) mice. Remarkably, a single injection of an inhibitory CpG sequence that blocks TLR9 protected WT mice, even when administered as late as 12 h after CLP. Our findings demonstrate that the detrimental immune response to bacterial sepsis occurs via TLR9 stimulation. TLR9 blockade is a potential strategy for the treatment of human sepsis.