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INTRODUCTION: Acute hemorrhagic leukoencephalitis (AHLE), a rare form of acute disseminated encephalomyelitis (ADEM), has a generally poor prognosis. However, significant variation is observed, and even complete recovery has been reported. The recent increase in the frequency of AHLE case reports is possibly contributed by the advent of COVID-19 and may have added to the heterogeneity of cases. METHODS: We report a fatal case of AHLE with a preceding unspecified respiratory infection, then perform a systematic review of AHLE, in an effort to delineate factors that may be associated with an ultimate outcome of severe disability (defined as modified Rankin scale score of 4 or 5) or death. RESULTS: Descriptions of 31 cases of AHLE were found in 21 identified articles, with our case being the 32nd case. The most common antecedent event was an infection (20 patients, 62.5%), with nearly half of these being COVID-19 (9 patients). The majority of patients had a subacute progression (1 to 10 days) from onset to clinical nadir. We found that an altered mental status (AMS) and a Glasgow Coma Scale (GCS) score of less than 12 were associated with a final outcome of severe disability or death. An abnormal upgoing plantar response was associated with a final outcome of death. COVID-19 and its vaccines were not associated with either outcome. CONCLUSION: AMS, depressed GCS, and an upgoing plantar response at presentation may be associated with a poor outcome in AHLE. Our findings may serve as a springboard to much-needed research into the stratification of AHLE.
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Developing an efficient heterogeneous photocatalyst for environmental remediation and treatment strategies using visible light harvesting processes is promising but challenging. Herein, Cd1-xCuxS materials have been synthesized and characterized by precise analytical tools. Cd1-xCuxS materials exhibited excellent photocatalytic activity for direct Red 23 (DR-23) dye degradation in visible light irradiation. The operational parameters, like dopant concentration, photocatalyst dose, pH, and initial concentration of dye were investigated during the process. The photocatalytic degradation process follows pseudo-first-order kinetics. As compared to other tested materials, 5% Cu doped CdS material revealed superior photocatalytic performance for the degradation of DR-23 (k = 13.96 × 10-3 min-1). Transient absorption spectroscopy, EIS, PL, and transient photocurrent indicated that adding copper to the CdS matrix improved the separation of photo-generated charge carriers by lowering the recombination rate. Spin-trapping experiments recognized the photodegradation primarily based on secondary redox products, i.e., hydroxyl and superoxide radicals. According to by Mott-Schottky curves, photocatalytic mechanism and photo-generated charge carrier density were elucidated regarding dopant-induced valence and conduction bands shifting. Thermodynamic probability of radical formation in line with the altered redox potentials by Cu doping has been discussed in the mechanism. The identification of intermediates by mass spectrometry study also showed a plausible breakdown mechanism for DR-23. Moreover, samples treated with nanophotocatalyst displayed excellent results when tested for water quality metrics such as DO, TDS, BOD, and COD. Developed nanophotocatalyst shows high recyclability with superior heterogeneous nature. 5% Cu-doped CdS also exhibit strong photocatalytic activity for the degradation of colourless pollutant bisphenol A (BPA) under visible light (k = 8.45 × 10-3 min-1). The results of this study offer exciting opportunities to alter semiconductors' electronic band structures for visible-light-induced photocatalytic activity for wastewater treatment.
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Cobre , Nanoporos , Cobre/química , Cádmio , Espécies Reativas de Oxigênio , Luz , Recombinação Genética , CatáliseRESUMO
Integration host factor (IHF) is a nucleoid-associated protein involved in DNA packaging, integration of viral DNA and recombination. IHF binds with nanomolar affinity to duplex DNA containing a 13 bp consensus sequence, inducing a bend of ~160° upon binding. We determined that IHF binds to DNA Four-way or Holliday junctions (HJ) with high affinity regardless of the presence of the consensus sequence, signifying a structure-based mechanism of recognition. Junctions, important intermediates in DNA repair and homologous recombination, are dynamic and can adopt either an open or stacked conformation, where the open conformation facilitates branch migration and strand exchange. Using ensemble and single molecule Förster resonance energy transfer (FRET) methods, we investigated IHF-induced changes in the population distribution of junction conformations and determined that IHF binding shifts the population to the open conformation. Further analysis of smFRET dynamics revealed that even in the presence of protein, the junctions remain dynamic as fast transitions are observed for the protein-bound open state. Protein binding alters junction conformational dynamics, as cross correlation analyses reveal the protein slows the transition rate at 1 mM Mg2+ but accelerates the transition rate at 10 mM Mg2+. Stopped flow kinetic experiments provide evidence for two binding steps, a rapid, initial binding step followed by a slower step potentially associated with a conformational change. These measurements also confirm that the protein remains bound to the junction during the conformer transitions and further suggest that the protein forms a partially dissociated state that allows junction arms to be dynamic. These findings, which demonstrate that IHF binds HJs with high affinity and stabilizes junctions in the open conformation, suggest that IHF may play multiple roles in the processes of integration and recombination in addition to stabilizing bacterial biofilms.
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DNA Cruciforme , Transferência Ressonante de Energia de Fluorescência , DNA Cruciforme/genética , Fatores Hospedeiros de Integração/genética , Fatores Hospedeiros de Integração/química , Fatores Hospedeiros de Integração/metabolismo , Conformação de Ácido Nucleico , DNA ViralRESUMO
PURPOSE: To evaluate the effect of brimonidine tartrate 0.025% ophthalmic solution on pupil size under scotopic conditions in healthy adults METHODS: Pupil size was measured in 56 eyes of 28 volunteer participants using a pupillometer under scotopic conditions. Age, gender, and iris color were recorded. Subjects using any ophthalmic medications other than artificial tears were excluded. The pupil size was subsequently measured again under scotopic conditions 60 min after instillation of brimonidine tartrate 0.025% ophthalmic solution. RESULTS: Statistically significant miosis was seen after instillation of brimonidine tartrate 0.025% (p = 0.04). Average pupil size prior to brimonidine 0.025% instillation was 7.28 ± 1.05 mm, and average pupil size after instillation of brimonidine 0.025% was 6.36 ± 1.68 mm, a reduction of - 23.7% in pupil area. Subjects with light irides demonstrated a greater miotic effect than subjects with dark irides (1.55 mm vs. 0.67 mm, p < 0.0001), with a pupil area reduction of - 37.6% and - 17.4%, respectively. The amount of miosis was independent of initial pupil size. CONCLUSIONS: Brimonidine tartrate 0.025% causes significant miosis in scotopic settings, although the effect is not as great in darker colored eyes. Further studies are needed to determine the latency and duration of the effect and whether the amount of miosis is clinically significant.
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Pupila , Quinoxalinas , Adulto , Tartarato de Brimonidina , Humanos , Lubrificantes Oftálmicos , Mióticos , Soluções OftálmicasRESUMO
A 55-year-old man presented with unilateral orbital inflammation and no light perception vision. Imaging revealed infiltrative enhancement of the optic nerve, orbit, and intracranial tissue. The case was suspicious for invasive fungal disease, but ultimate workup and orbital biopsy revealed granulomatosis with polyangiitis. The patient's inflammation resolved with corticosteroid and rituximab therapy. Granulomatosis with polyangiitis is a systemic vasculitis that can mimic a number of orbital pathologies.
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Aspergilose/diagnóstico , Infecções Oculares Fúngicas/diagnóstico , Granulomatose com Poliangiite/diagnóstico , Doenças Orbitárias/diagnóstico , Sinusite/diagnóstico , Aspergilose/microbiologia , Aspergillus flavus/isolamento & purificação , Biópsia , Diagnóstico Diferencial , Quimioterapia Combinada , Infecções Oculares Fúngicas/microbiologia , Glucocorticoides/uso terapêutico , Granulomatose com Poliangiite/tratamento farmacológico , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doenças Orbitárias/tratamento farmacológico , Doenças Orbitárias/microbiologia , Rituximab/uso terapêutico , Sinusite/microbiologiaAssuntos
Academias e Institutos/normas , Extração de Catarata/normas , Catarata/patologia , Atenção à Saúde/normas , Oftalmologia/organização & administração , Padrões de Prática Médica/normas , Adulto , Humanos , Refração Ocular/fisiologia , Fatores de Risco , Inquéritos e Questionários , Resultado do Tratamento , Transtornos da Visão/reabilitação , Acuidade Visual/fisiologiaRESUMO
We report experimental observation of intrinsic Bloch-mode emission from a 3D tungsten photonic crystal at low thermal excitation. After the successful removal of conventional metallic emission (normal emission), it is possible to make an accurate comparison of the Bloch-mode and the normal emission. For all biases, we found that the emission intensity of the Bloch-mode is higher than that of the normal emission. The Bloch-mode emission also exhibits a slower dependence on [Formula: see text] than that of the normal emission. The observed higher emission intensity and a different T-dependence is attributed to Bloch-mode assisted emission where emitters have been located into a medium having local density of states different than the isotropic case. Furthermore, our finite-difference time-domain (FDTD) simulation shows the presence of localized spots at metal-air boundaries and corners, having intense electric field. The enhanced plasmonic field and local non-equilibrium could induce a strong thermally stimulated emission and may be the cause of our unusual observation.
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PURPOSE: To comprehensively investigate spectral domain optical coherence tomography features associated with Type 3 neovascularization and determine the prevalence of each feature and to develop an updated staging system for Type 3 neovascularization based on spectral domain optical coherence tomography findings. METHODS: The authors retrospectively analyzed 34 eyes with new-onset Type 3 neovascularization. Spectral domain optical coherence tomography images at onset of Type 3 neovascularization, immediately after the first injection, and at the final quiescent visit were analyzed for the presence of specific optical coherence tomography features. In addition, when available, optical coherence tomography images from the visit before onset were studied. RESULTS: Among 18 eyes with preonset optical coherence tomography, 77.8% had preexisting intraretinal hyperreflective foci (precursor lesion). In the same group of eyes, 44.4% and 27.8% exhibited outer plexiform layer disruption and outer plexiform layer downward deflection, respectively. At the onset of detectable Type 3 neovascularization, all 34 eyes demonstrated a hyperreflective focus with cystoid macular edema and 85.3% exhibited disruption of the retinal pigment epithelium. Serous pigment epithelial detachment and subretinal fluid were present in 67.6% and 23.5% of eyes at onset, respectively. The rate of cystoid macular edema decreased from 100% to 17.6% after a single injection. At the final quiescent visit, focal atrophy at the site of Type 3 lesions, as evidenced by outer retinal and retinal pigment epithelium disruption developed in 88.2% and 52.9% of eyes, respectively. CONCLUSION: An updated staging system of Type 3 lesions was developed based on spectral domain optical coherence tomography findings. A precursor stage consists of a punctate hyperreflective focus in the outer retina. The subtle detection of associated outer plexiform layer disruption and downward deflection may indicate that this precursor lesion is more likely to progress to an active Type 3 neovascular lesion. Stage 1 consists of a larger intraretinal hyperreflective lesion associated with cystoid macular edema but without outer retinal disruption. Stage 2 is notable for outer retinal disruption that occurs with retinal pigment epithelium disruption in most of the cases. Stage 3 is defined by an intraretinal hyperreflective lesion that extends through the retinal pigment epithelium to vascularize a drusenoid pigment epithelial detachment creating a serous component of the pigment epithelial detachment.
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Edema Macular/diagnóstico por imagem , Epitélio Pigmentado da Retina/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Edema Macular/patologia , Masculino , Pessoa de Meia-Idade , Epitélio Pigmentado da Retina/patologia , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos , Acuidade VisualRESUMO
We report some striking results on thermal radiation properties of a resonantly coupled cavity photonic crystal (PhC) at elevated temperatures (T = 400-900 K). We experimentally found that at resonant wavelengths, λ = 1.1, 1.64, 2.85 µm, the PhC emission is spectrally selective, quasi-coherent, directional, and shows significant deviation from Planck's blackbody law at equilibrium. The presence of non-equilibrium effects, driven by strong thermal excitation and cavity resonance, may be the major cause for our experimental observation.
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The possibility for controlling both the probe-field optical gain and absorption, as well as photon conversion by a surface-plasmon-polariton near field is explored for a quantum dot located above a metal surface. In contrast to the linear response in the weak-coupling regime, the calculated spectra show an induced optical gain and a triply-split spontaneous emission peak resulting from the interference between the surface-plasmon field and the probe or self-emitted light field in such a strongly-coupled nonlinear system. Our result on the control of the mediated photon-photon interaction, very similar to the 'gate' control in an optical transistor, may be experimentally observable and applied to ultra-fast intrachip/interchip optical interconnects, improvement in the performance of fiber-optic communication networks, and developments of optical digital computers and quantum communications.
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The unprecedented ability of metallic subwavelength structures to confine and concentrate light into subwavelength spaces has led to new physics and exploration of novel devices. In this Letter, we demonstrate a 20 times enhancement of intersubband photoresponse in a InAs quantum dot (QD) system due to evanescently coupled plasmonic field. The resulting enhancement is accompanied by significant narrowing of photoresponse linewidth. The strong enhancement is attributed to efficient coupling of incident field to surface modes and to QDs, the presence of polarization-dependent absorption from QDs, and a fairly strong plasmon-QD interaction.
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In patients with lung adenocarcinoma, angiogenesis-altering drugs can alter the appearance of leptomeningeal metastasis on magnetic resonance imaging (MRI) scans. In the ventral brainstem, this can manifest as a unique, linear, non-enhancing T2-hyperintense signal.
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We report what is to our knowledge the first observation of the effect of parallel-to-interface-refraction (PIR) in a three-dimensional, simple-cubic photonic-crystal. PIR is an acutely negative refraction of light inside a photonic-crystal, leading to light-bending by nearly 90 deg over broad wavelengths (λ). The consequence is a longer path length of light in the medium and an improved light absorption beyond the Lambertian limit. As an illustration of the effect, we show near-unity total absorption (≥98%) in λ=520-620 nm and an average absorption of ~94% over λ=400-700 nm for our α-Si:H photonic-crystal sample of an equivalent bulk thickness of tË=450 nm. Furthermore, we have achieved an ultra-wide angular acceptance of light over θ=0°-80°. This demonstration opens up a new door for light trapping and near-unity solar absorption over broad λs and wide angles.
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We report a direct observation of a quasi-coherent thermal emission from a heated three-dimensional photonic-crystal sample. While the sample was under Joule heating, we observed multiple oscillations in its emission interferogram and deduced a coherent length of L(coh)â (20-40) µm, 5-10 times longer than that of a blackbody at comparable wavelengths. The observed, relatively long coherent length is attributed to coupling of thermal emission into lossy Bloch modes that oscillate coherently over a distance determined by decay length and the slow light nature of Bloch modes at the band-edges.
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BACKGROUND/OBJECTIVES: We provide global averages and standard deviations for ocular biometry-axial length (AL), corneal radius of curvature (CR), anterior chamber depth (ACD), lens thickness (LT), white to white (WTW), and central corneal thickness (CT). We hope a better understanding of normal and abnormal values will help clinicians gain further insight into their surgical outcomes, especially for off-target eyes. SUBJECTS/METHODS: We searched the MEDLINE database using keywords "axial length, corneal power, anterior chamber depth, lens thickness, white to white, and corneal thickness." We included studies that reported averages and standard deviations on eye biometry for at least 1300 eyes. Global weighted averages and standard deviations were calculated using the Cochrane method. RESULTS: Fourteen studies were included, originating from Asia (Japan, Singapore, Myanmar, Iran, South Korea, China), Europe (Germany, United Kingdom, Portugal), Australia, and North America (United States). Global ocular biometry metrics were: AL-23.49 mm ± 1.35 mm, CR-7.69 mm ± 0.28 mm, ACD-3.10 mm ± 0.47 mm, WTW-11.80 mm ± 0.42 mm, LT-4.37 mm ± 0.43 mm, and CT-544 µm ± 38 µm. Total eyes per value ranged from 19,538 to 90,814. CONCLUSIONS: We report global ocular biometry averages and standard deviations. No eyes were from studies in Africa or South America, highlighting the need to publish eye biometry data from these continents. We hope that promoting a deeper understanding of biometry values will help clinicians gain insight into surgical outcomes and drive innovations in lens calculations.
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Comprimento Axial do Olho , Cristalino , Humanos , Comprimento Axial do Olho/anatomia & histologia , Córnea/anatomia & histologia , Coleta de Dados , Biometria/métodos , Câmara Anterior/anatomia & histologia , Refração OcularRESUMO
We describe the first case of anti-CV2 paraneoplastic polyneuropathy associated with lung adenocarcinoma. Our patient presented with progressive unsteadiness and numbness involving bilateral upper and lower limbs. He had symmetrical length-dependent lower motor neuron pattern of weakness and numbness involving both small and large fibres with prominent sensory ataxia. An extended workup for the polyneuropathy involving a serum paraneoplastic antineuronal antibody panel showed a positive reaction for anti-CV2 antibody. CT scan of the thorax, abdomen and pelvis revealed a right upper lung nodule and histopathological examination of the nodule revealed lung adenocarcinoma. He was scheduled for chemotherapy following his discharge and there was improvement of his sensorimotor polyneuropathy following his chemotherapy.
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Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Polineuropatia Paraneoplásica , Masculino , Humanos , Polineuropatia Paraneoplásica/etiologia , Hipestesia , Adenocarcinoma de Pulmão/complicações , Neurônios Motores/patologia , Neoplasias Pulmonares/patologia , AutoanticorposRESUMO
We describe a case of infiltrative optic neuropathy with hypertrophic pachymeningitis noted on MRI of the brain, presenting a diagnostic dilemma with a wide variety of differential diagnoses to consider. Our patient is a middle-aged woman with a 20-year history of migranous-sounding headaches who was incidentally found to have worsening vision in her left eye during a routine driving test visual acuity check. Neurological examination revealed a left grade III relative afferent pupillary defect and a central scotoma with red desaturation. Subsequent MRI of her brain and anterior visual pathway revealed features suggestive of an infiltrative left optic neuropathy with hypertrophic pachymeningitis. An extended workup including diagnostic lumbar puncture and blood tests for possible autoimmune, infective and neoplastic causes proved unyielding. Eventually, an endoscopic transsphenoidal biopsy helped to clinch the diagnosis of a (meningothelial subtype) WHO grade 1 meningioma as the cause of her clinical and radiological presentation.
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Neoplasias Meníngeas , Meningioma , Meningite , Doenças do Nervo Óptico , Pessoa de Meia-Idade , Feminino , Humanos , Meningioma/diagnóstico , Meningioma/diagnóstico por imagem , Doenças do Nervo Óptico/etiologia , Doenças do Nervo Óptico/complicações , Meningite/complicações , Meningite/diagnóstico , Transtornos da Visão/etiologia , Hipertrofia/complicações , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/diagnóstico por imagemRESUMO
In this study, we demonstrated the synthesis of potassium chloride (KCl)-incorporated graphitic carbon nitride, (g-C3N4, CN) with varying amounts of N-vacancies and pyridinic-N as well as enhanced Lewis basicity, via a single-step thermal polymerization by tailoring the precursors of melamine and urea for carbon oxide (CO2) capture. Melamine, as a precursor, undergoes a phase transformation into melam and triazine-rich g-C3N4, whereas the addition of urea polymerizes the mixture to form melem and heptazine-rich g-C3N4 (CN11). Owing to the abundance of pyridinic-N and the high surface area, CN11 adsorbed higher amounts of CO2 (44.52 µmol m-2 at 25 °C and 1 bar of CO2) than those reported for other template-free carbon materials. Spectroscopic analysis revealed that the enhanced CO2 adsorption is due to the presence of pyridinic-N and Lewis basic sites on the surface. The intermediates of CO2adsorption, including carbonate and bicarbonate species, attached to the CN samples were identified using in-situ Fourier-transform infrared spectroscopy (FTIR). This work provides insights into the mechanism of CO2 adsorption by comparing the structural features of the synthesized KCl-incorporated g-C3N4 samples. CN11, with an excellent CO2 uptake capacity, is viewed as a promising candidate for CO2 capture and storage.
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Dióxido de Carbono , Ureia , Cloreto de Potássio , Dióxido de Carbono/química , Adsorção , Ureia/química , Triazinas/químicaRESUMO
Despite the modern boost, developing a new photocatalytic system for the reduction of aldehydes is still challenging due to their high negative reduction potential. Herein, we have used a metal-free photoinduced electron-transfer system based on a cheap and readily available organic dye eosin Y (EY), graphene oxide (GO), and ammonium oxalate (AO) for photocatalytic reduction of structurally diverse aldehydes under sustainable conditions. The protocol shows remarkable selectivity for the photocatalytic reduction of aldehydes over ketones. The decisive interaction of GO and AO with the various states of EY (ground, singlet, triplet, and radical anions), which are responsible for the commencement of the reaction, was examined by various theoretical, optical, electrochemical, and photo-electrochemical studies. The synergetic system of GO, EY, and AO is appropriate for enhancing the separation efficiency of visible-light-induced charge carriers. GO nanosheets act as an electron reservoir to accept and transport photogenerated electrons from the photocatalytic system to the reactant. The reduction of the GO during the process ruled out the back transfer of photoexcited charges. Control experiments explained that the reaction involves two stages: electron transfer and protonation. This process eliminates the necessity of precious-metal-based photocatalysts or detrimental sacrificial agents and overcomes the redox potential limitations for the photoreduction of aldehydes.
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Sulfide-based solid-state lithium-ion batteries (SSLIB) have attracted a lot of interest globally in the past few years for their high safety and high energy density over the traditional lithium-ion batteries. However, sulfide electrolytes (SEs) are moisture-sensitive which pose significant challenges in the material preparation and cell manufacturing. To the best of our knowledge, there is no tool available to probe the types and the strength of the basic sites in sulfide electrolytes, which is crucial for understanding the moisture stability of sulfide electrolytes. Herein, we propose a new spectral probe with the Lewis base indicator BBr3 to probe the strength of Lewis basic sites on various sulfide electrolytes by 11B solid-state NMR spectroscopy (11B-NMR). The active sulfur sites and the corresponding strength of the sulfide electrolytes are successfully evaluated by the proposed Lewis base probe. The probed strength of the active sulfur sites of a sulfide electrolyte is consistent with the results of DFT (density functional theory) calculation and correlated with the H2S generation rate when the electrolyte was exposed in moisture atmosphere. This work paves a new way to investigate the basicity and moisture stability of the sulfide electrolytes.