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1.
BMC Neurol ; 24(1): 276, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39123191

RESUMO

BACKGROUND: Recognizing the predictors of poor short-term prognosis after first-line immunotherapy in patients with anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is essential for individualized treatment strategy. The objective of this study was to ascertain the factors that forecast short-term prognosis in patients with anti-NMDAR encephalitis, develop a prognostic prediction model, and authenticate its efficacy in an external validation cohort. Further, all patients were followed-up long-term to assess the factors of long-term outcome and relapses. METHODS: A prospective enrollment of patients diagnosed with anti-NMDAR encephalitis was conducted across five clinical centers in China from June 2014 to Mar 2022. The enrolled patients were divided into the derivation and validation sets based on enrollment time. The short-term prognostic model was visualized using a nomogram. Further, all patients were followed-up long-term to assess the factors of long-term outcome. RESULTS: This study found that poor short-term prognosis was a risk factor for poor long-term outcome (6-month prognosis, OR 29.792, 95%CI 6.507-136.398, p < 0.001; 12-month prognosis, OR 15.756, 95%CI 3.384-73.075, p < 0.001; 24-month prognosis, OR 5.500, 95%CI 1.045-28.955, p = 0.044). Abnormal behavior or cognitive dysfunction (OR 8.57, 95%CI 1.48-49.79, p = 0.017), consciousness impairment (OR19.32, 95%CI 3.03-123.09, p = 0.002), autonomic dysfunction or central hypoventilation (OR 5.66, 95%CI 1.25-25.75, p = 0.025), CSF pleocytosis (OR 4.33, 95%CI 1.48-12.65, p = 0.007), abnormal EEG (OR 5.48, 95% CI 1.09-27.54, p = 0.039) were independent predictors for a poor short-term prognosis after first-line immunotherapy. A nomogram that incorporated those factors showed good discrimination and calibration abilities. The area under the curve (AUC) for the prognostic model were 0.866 (95%CI: 0.798-0.934) with a sensitivity of 0.761 and specificity of 0.869. CONCLUSION: We established and validated a prognostic model that can provide individual prediction of short-term prognosis after first-line immunotherapy for patients with anti-NMDAR encephalitis. This practical prognostic model may help neurologists to predict the short-term prognosis early and potentially assist in adjusting appropriate treatment timely.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato , Humanos , Encefalite Antirreceptor de N-Metil-D-Aspartato/diagnóstico , Masculino , Feminino , Prognóstico , Adulto , China/epidemiologia , Adulto Jovem , Adolescente , Estudos Prospectivos , Criança , Pessoa de Meia-Idade , Nomogramas , Seguimentos , População do Leste Asiático
2.
Nano Lett ; 23(18): 8505-8514, 2023 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-37695636

RESUMO

Considerable efforts have been made to develop nanoparticle-based magnetic resonance contrast agents (CAs) with high relaxivity. The prolonged rotational correlation time (τR) induced relaxivity enhancement is commonly recognized, while the effect of the water coordination numbers (q) on the relaxivity of nanoparticle-based CAs gets less attention. Herein, we first investigated the relationship between T1 relaxivity (r1) and q in manganese-based hybrid micellar CAs and proposed a strategy to enhance the relaxivity by increasing q. Hybrid micelles with different ratios of amphiphilic manganese complex (MnL) and DSPE-PEG2000 were prepared, whose q values were evaluated by Oxygen-17-NMR spectroscopy. Micelles with lower manganese doping density exhibit increased q and enhanced relaxivity, corroborating the conception. In vivo sentinel lymph node (SLN) imaging demonstrates that DSPE-PEG/MnL micelles could differentiate metastatic SLN from inflammatory LN. Our strategy makes it feasible for relaxivity enhancement by modulating q, providing new approaches for the structural design of high-performance hybrid micellar CAs.


Assuntos
Micelas , Água , Manganês/química , Linfografia , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Meios de Contraste/química
3.
Angew Chem Int Ed Engl ; 63(8): e202315599, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38169100

RESUMO

Polypeptides, as natural polyelectrolytes, are assembled into tailored proteins to integrate chromophores and catalytic sites for photosynthesis. Mimicking nature to create the water-soluble nanoassemblies from synthetic polyelectrolytes and photocatalytic molecular species for artificial photosynthesis is still rare. Here, we report the enhancement of the full-spectrum solar-light-driven H2 production within a supramolecular system built by the co-assembly of anionic metalloporphyrins with cationic polyelectrolytes in water. This supramolecular photocatalytic system achieves a H2 production rate of 793 and 685 µmol h-1 g-1 over 24 h with a combination of Mg or Zn porphyrin as photosensitizers and Cu porphyrin as a catalyst, which is more than 23 times higher than that of free molecular controls. With a photosensitizer to catalyst ratio of 10000 : 1, the highest H2 production rate of >51,700 µmol h-1 g-1 with a turnover number (TON) of >1,290 per molecular catalyst was achieved over 24 h irradiation. The hierarchical self-assembly not only enhances photostability through forming ordered stackings of the metalloporphyrins but also facilitates both energy and electron transfer from antenna molecules to catalysts, and therefore promotes the photocatalysis. This study provides structural and mechanistic insights into the self-assembly enhanced photostability and catalytic performance of supramolecular photocatalytic systems.

4.
Neurol Sci ; 44(7): 2465-2474, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36781561

RESUMO

OBJECTIVE: To detect the alteration of regulatory B cells (Bregs), follicular helper T cells (Tfh), and regulatory T cells (Tregs) frequencies in patients with anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis. Analyze their association with clinical severity and activity, and explore the effects of different immunotherapies on those immune cell subsets. METHODS: We enrolled 21 patients with anti-NMDAR encephalitis, 22 patients with neuromyelitis optica spectrum disorder (NMOSD), 14 patients with idiopathic intracranial hypertension (IIH), and 20 healthy controls (HC) in our study. The frequencies of various immune cell subsets were determined using flow cytometry. RESULTS: Compared to patients with IIH and HC, the frequencies of CD24hiCD38hi transitional B cells as well as Tregs were significantly lower while the frequency of Tfh was significantly higher in patients with anti-NMDAR encephalitis. The frequency of CD24hiCD38hi transitional B cells was significantly lower in the acute stage than in the recovery stage, and was negatively correlated with the modified Rankin scale (mRS) and the clinical assessment scale for autoimmune encephalitis (CASE). The frequency of CD24hiCD38hi transitional B cells at the last follow-up after rituximab (RTX) treatment was significantly higher than those treated with oral immunosuppressants or untreated. There was no clear difference between anti-NMDAR encephalitis and NMOSD in the above immune cell subsets. CONCLUSION: We suggested that the frequencies of CD24hiCD38hi transitional B cells and Tregs were decreased while the frequency of Tfh was increased in patients with anti-NMDAR encephalitis. CD24hiCD38hi transitional B cells frequency may be a potential indicator to estimate the disease activity and severity.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato , Linfócitos B Reguladores , Neuromielite Óptica , Humanos , Encefalite Antirreceptor de N-Metil-D-Aspartato/terapia , Células T Auxiliares Foliculares , Citometria de Fluxo , Linfócitos T Reguladores
5.
Angew Chem Int Ed Engl ; 62(48): e202311224, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37840434

RESUMO

Fluorescent materials with high brightness play a crucial role in the advancement of various technologies such as bioimaging, photonics, and OLEDs. While significant efforts are dedicated to designing new organic dyes with improved performance, enhancing the brightness of existing dyes holds equal importance. In this study, we present a simple supramolecular strategy to develop ultrabright cyanine-based fluorescent materials by addressing long-standing challenges associated with cyanine dyes, including undesired cis-trans photoisomerization and aggregation-caused quenching. Supra-cyanines are obtained by incorporating cyanine moieties in a cyclic peptide-based supramolecular scaffold, and exhibit high fluorescence quantum yields (up to 50 %) in both solution and in the solid state. These findings offer a versatile approach for constructing highly emissive cyanine-based supramolecular materials.

6.
J Neuroophthalmol ; 42(2): e523-e525, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35482897

RESUMO

ABSTRACT: We report a case of pendular seesaw nystagmus caused by bitemporal hemianopia; the nystagmus disappeared while in darkness as previously described, but it also disappeared with monocular occlusion, which indicates the pivotal role of binocular vision in the pathogenesis.


Assuntos
Nistagmo Patológico , Hemianopsia , Humanos , Nistagmo Patológico/diagnóstico , Nistagmo Patológico/etiologia , Nistagmo Patológico/patologia , Visão Binocular
7.
J Neuroophthalmol ; 40(1): 30-36, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32045392

RESUMO

OBJECTIVE: The primary aim of this study was to describe clinical features of Chinese sporadic Leber hereditary optic neuropathy (LHON) caused by rare primary mitochondrial DNA (mtDNA) mutations. METHODS: We characterized a Chinese patient cohort with rare primary mtDNA mutations at Beijing Tongren Hospital between 2015 and 2018. The clinical features of these patients were retrospectively recorded and analyzed. RESULTS: Sixteen patients with LHON who had the selected rare primary mutations, including m.4171C>A (3 patients), m.10197G>A (1 patient), m.14459G>A (4 patients), and m.14502T>C (8 patients), were evaluated. The mean age at disease onset was 15 ± 6 years, and the male to female ratio was 15:1. Of 32 eyes of all patients, 75% (24/32) had a worst Snellen best-corrected visual acuity ≤0.1 (worse than 20/200), while 67% (2/3) who were carrying the m.4171C>A mutation experienced significant visual improvement. In addition, 40% (2/5) of patients with LHON carrying only m.14502T>C mutation had only mild visual impairment. Isolated manifestations of LHON was present in 94% (15/16) of all patients; 1 patient with the m.14459G>A mutation had LHON plus dystonia. Brain MRI T2 short tau inversion recovery sequences demonstrated optic atrophy in 62.5% (10/16); increased T2 signal in the optic nerve was found in 38% (6/16) of patients. The patient with LHON plus dystonia demonstrated optic atrophy and increased T2 signal in basal ganglia. CONCLUSION: Patients with LHON and rare primary mutations have diverse clinical phenotypes. Those with the m.4171C>A mutation are more likely to have a good visual prognosis, while the m.14502T>C mutation may play a synergistic role in disease onset. Increased signal in the optic nerve on MRI is not rare, and this feature should not exclude LHON as the potential cause for optic neuropathy.


Assuntos
DNA Mitocondrial/genética , Mutação , Atrofia Óptica Hereditária de Leber/diagnóstico , Fenótipo , Adolescente , Adulto , Povo Asiático/genética , Criança , Pré-Escolar , China , Feminino , Humanos , Masculino , Atrofia Óptica Hereditária de Leber/genética , Estudos Retrospectivos , Adulto Jovem
8.
Langmuir ; 35(40): 13100-13109, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31513421

RESUMO

Many commercially and industrially important materials aggregate to form nanoscale mass-fractal structures. Unlike hard aggregates such as fumed silica, aqueous pigment-based inks consist of weakly bound nanoparticles stabilized by a surfactant. These soft aggregates can easily break apart and re-form balancing mixing energy and the reduction in surface energy with clustering or aggregation. Rapid thermal motion of small elemental crystallites leads to dense clusters or primary particles. The larger primary particles have slower thermal motion and aggregate into ramified mass fractals to form a dual-level hierarchical structure. It is proposed that the hierarchical structure relies on subtle and competitive equilibria between the different hierarchical structural levels. A new hierarchical thermodynamics model by Vogtt is used. Pigment yellow 14 and pigment blue 15:3 as surfactant-stabilized aqueous dispersions were employed to explore the thermodynamics of nanoparticle hierarchical equilibria. It was demonstrated that reversible nanoparticle aggregation can be described solely by the change in free energy of dissociation and the change in free energy of mixing in the context of a subunit being removed from a cluster. The hierarchical thermodynamics is dominated by the solubility of the dispersing surfactant. At the cloud point for the surfactant, primary particles approach the size of an elemental particle and the degree of aggregation becomes very large. The results indicate that subtle and reproducible control over pigment hierarchical structure and size is possible through thermal equilibration, manipulation of the surfactant properties, and elemental crystallite size.

9.
Soft Matter ; 15(4): 642-655, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30608505

RESUMO

We combine mechanical rheometry, diffusing wave spectroscopy (DWS), and small angle neutron scattering (SANS) with a simulation model, the "pointer algorithm", to obtain characteristic lengths and time constants for wormlike micelle (WLM) solutions over a range of salt concentrations encompassing the transition from unentangled to entangled solutions. The solutions contain sodium lauryl ethylene glycol sulfate (SLE1S), cocamidopropyl betaine (CAPB), and NaCl. The pointer algorithm is extended to include relaxation of unentangled micelles, allowing micelle parameters to be extracted from the rheology of partially entangled solutions. DWS provides the data at high frequency needed to determine micelle persistence length accurately. From pointer algorithm fits to rheology, we observe a salt-induced rapid change in micellar length as the solution enters the well-entangled regime and a weaker growth with surfactant concentration consistent with mean-field theory. At a lower surfactant concentration, micelle length and persistence length from SANS are roughly consistent with values from rheology once the lower surfactant concentration used in SANS is accounted for. This is, to our knowledge, the first time that quantitative comparisons of structural features including micelle length are made between rheology and SANS. Finally, scaling laws for micelle diffusion and recombination times indicate that micelle kinetics are reaction controlled leading to mean-field recombination with surrounding micelles over the entire range of concentration of interest except at very low and very high surfactant concentrations where either short micelles or branched micelle clusters are dominant.

10.
BMC Ophthalmol ; 19(1): 124, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31174513

RESUMO

BACKGROUND: To analyze the clinical features and prognosis of the visual loss resulted from inhalational methanol poisoning in 8 Chinese patients. METHODS: Eight consecutive patients seen at the Beijing Tongren Hospital of Capital Medical University, Beijing, China between January 2003 to August 2017, with complains of vision loss in both eyes, identified as inhalational methanol poisoning. Detailed medical history was extracted. All patients underwent optic nerve and brain magnetic resonance imaging (MRI) scan, laboratory tests, and visual function analysis. Treatment protocols were large dosage of methylprednisolone and B vitamins over 3 months. Patients were seen at 3-month intervals until a year. RESULTS: Eight patients with optic neuropathy caused by inhalation toxicity of methanol were under observation, whose methanol-contact time spans were form 4 days to 5 years for occupational exposure. All the patients had acute onset, transient systemic symptoms on early stage, both eyes involved with severe visual impairment (visual acuity 0.1 or even worse). Retrobulbar optic nerves (ONs) were the major sites involved. Optic nerve MRI scan showed increased signal of bilateral ONs in the orbit and the canal parts, with enhancement. After treatment, the visual function of these patients got improved in different degree in a year follow-up, but not satisfactorily. CONCLUSIONS: Inhalational methanol toxicity may lead to serious damage to ON in a process of chronic intoxication with acute attack, and with poor prognosis.


Assuntos
Metanol/intoxicação , Nervo Óptico/efeitos dos fármacos , Transtornos da Visão/induzido quimicamente , Acuidade Visual/fisiologia , Doença Aguda , Administração por Inalação , Adulto , Encéfalo/diagnóstico por imagem , Doença Crônica , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Metanol/administração & dosagem , Pessoa de Meia-Idade , Nervo Óptico/patologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Solventes/intoxicação , Transtornos da Visão/diagnóstico , Transtornos da Visão/fisiopatologia , Acuidade Visual/efeitos dos fármacos , Adulto Jovem
11.
J Neuroophthalmol ; 39(1): 56-59, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-29554000

RESUMO

OBJECTIVE: To assess quality of life (QoL) measures in Chinese Leber hereditary optic neuropathy (LHON) patients with the G11778A mutation. METHODS: Chinese LHON patients with the G11778A mutation were prospectively evaluated using the Visual Function Index (VF-14) at 6 months, 1 year, and 3 years after the involvement of the second eye. Patients who completed the VF-14 at all 3 follow-up time designations were included in the analysis. RESULTS: Fifty-five patients met the inclusion criteria. The median age of patients when their vision was bilaterally affected was 16.3 years old (interquartile range: 13.9-18.3 years). In our patient cohort, 89.1% (n = 49) were male, and the ratio of males to females was 8.2:1. The median logMAR visual acuity was 2.0 (interquartile range: 1.0-2.6). The mean VF-14 scores of patients with LHON at 6-month, 1-year, and 3-year follow-ups were 18.0 ± 19.2 (range 0-85.4), 19.9 ± 20.0 (range 0-85.4), and 20.7 ± 20.2 (range 0-85.4), and the differences were statistically significant (P < 0.001). VF-14 score at 6 months was significantly correlated with visual acuity of the better eye (P < 0.001) but not with age of onset (P = 0.43). Overall, the QoL improvement was significantly correlated with age of onset (P = 0.006) but not with visual acuity of the better eye (P = 0.134). Several abilities were significantly improved at the 1-year follow-up compared with the 6-month follow-up, including seeing steps, curbs, or stairs (P < 0.01), doing handiwork (P < 0.05), playing sports (P < 0.05), cooking (P < 0.01), and watching television (P < 0.05). When these scores were further compared between 1- and 3-year follow-ups, only scores for cooking (P < 0.05) and watching television (P < 0.05) were higher at the 3-year follow-up than that at the 1-year follow-up. No changes were found during the follow-up for reading small print, reading a newspaper or book, or reading signs. CONCLUSIONS: Our results indicate that although most of our Chinese LHON patients with the G11778A mutation had permanent central visual loss, visual-related quality of life improved over time, especially in younger patients.


Assuntos
DNA Mitocondrial/genética , Mutação , Atrofia Óptica Hereditária de Leber/genética , Qualidade de Vida , Acuidade Visual , Adolescente , China/epidemiologia , Análise Mutacional de DNA , Progressão da Doença , Feminino , Seguimentos , Humanos , Incidência , Masculino , Atrofia Óptica Hereditária de Leber/diagnóstico , Atrofia Óptica Hereditária de Leber/epidemiologia , Disco Óptico/patologia , Linhagem , Estudos Prospectivos , Fatores de Tempo , Tomografia de Coerência Óptica
12.
Langmuir ; 34(46): 13956-13964, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30351052

RESUMO

The free scission energy is the thermodynamic parameter that governs the contour length of wormlike micelles (WLMs). It is the contour length and the propensity to coil and entangle that determine the viscoelastic properties of this commercially important substance class. The free scission energy Δ Fsc and the associated change in enthalpy Δ Hsc and entropy Δ Ssc on scission have been determined for a mixed anionic/zwitterionic surfactant system (sodium laureth sulfate and cocamidopropyl betaine) at various salt concentrations (3-5 wt % NaCl). Both enthalpy Δ Hsc and entropy Δ Ssc changes decrease linearly with increasing NaCl concentration. At NaCl concentrations above 4 wt %, Δ Ssc even adopts negative values. The term TΔ Ssc decreases more rapidly than Δ Hsc around room temperature and causes the observed elongation of WLMs upon addition of NaCl. It is suggested that Δ Ssc is initially positive due to fewer bound counterions per surfactant molecule at end caps compared to the intact, cylindrical parts before scission, leading to a net release of ions upon scission. Negative values of Δ Ssc are attributed to hydrophobic hydration occurring at the end caps at high salt concentrations. 23Na NMR measurements indicate the presence of immobilized ions, supporting a previously proposed ion-cloud model based on neutron scattering results.

13.
Langmuir ; 33(8): 1872-1880, 2017 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-28135107

RESUMO

Wormlike micelles (WLMs) are nanoscale, self-assembled components of many products from shampoos to fracking fluids due to their viscoelasticity. Their rheological behavior is largely governed by the contour length of the micelles and the concomitant propensity of the micelles to overlap and entangle. The large contour lengths, on the order of micrometers, is the result of a delicate balance between the scission enthalpy of the wormlike micelles on the one hand and entropic factors such as the mixing entropy of dispersion, the ordering of water molecules and counterions, and the mobility of branch points on the other hand. The structure and contour length of wormlike micelles assembled from sodium laureth-1-sulfate was determined at various temperatures using small-angle neutron scattering. The results allow the calculation of the enthalpy and entropy as well as the free energy of scission and are employed to critically evaluate the common methods to determine micellar scission energy from mean-field theory. Interesting behavior is observed when comparing branched and unbranched WLMs that may reflect on mechanistic differences in chain scission.

14.
Langmuir ; 33(49): 14029-14037, 2017 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-29144144

RESUMO

Particle dispersions, such as pigment-based inks, comprise weakly bound, milled nanoparticles. The properties of these pigments depend on both their chemical composition and a rather complex structural hierarchy which emerges from these dispersions. The emergence of structure under semidilute conditions is related to the structure of the dilute particles, the particle spacing (mesh size), processing history, and the interaction potential. Kinetic simulations could predict such emergence using these input parameters. In this paper, organic pigments are studied as an example of the importance of emergent structure to predict properties such as brilliance and opacity. Organic pigments are used to impart color to commercial inks, plastics, coatings, and cosmetics. In many cases, dilute pigments are mass fractal structures consisting of aggregated nanoparticles held together by weak van der Waals forces. In water, surfactant is added to create a pigment dispersion (an ink). The final properties of a pigment emerge from a complex interplay between aggregation and dispersion of aggregates as a function of concentration. Samples of the organic pigment yellow 14, PY14, were milled to four primary particle sizes to study the effect on structural emergence. The interaction between surfactant-stabilized PY14 aggregates in an aqueous medium was quantified by the second virial coefficient, A2, which reflects long-range interactions. The degree of aggregation is associated with short-range attractive interactions between primary particles. In this series of pigments, the degree of aggregation increases dramatically with reduction in primary particle size. Concurrently, the second-order virial coefficient, A2, increases reflecting stronger long-range repulsive interactions with particle size. Structural emergence can be understood through the percolation concentration and the filler mesh size. A2 is translated into a repulsive interaction potential for use in dissipative particle dynamics simulations to enable predictive modeling. This description of the interactions between dispersed pigment aggregates allows for a more scientific and predictive approach to understand structural emergence.

15.
Soft Matter ; 13(36): 6068-6078, 2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28782782

RESUMO

Worm-like micelles (WLMs) are nano-scale self-assemblies widely used for viscosity enhancement, for drug delivery, and in personal care products. The stability of WLMs under variable ionic and surfactant concentrations is important to applications of these fascinating materials. In this work it is demonstrated that a virial approach can be used to understand and predict WLM stability. A mixed surfactant system consisting of sodium laureth sulfate and cocoamidopropyl betaine was examined using small-angle neutron scattering. A linear relationship between the second virial coefficient, A2, and the salt to surfactant ratio, Θs-s, is derived and demonstrated. The Θs-s-dependent term is described via association/dissociation kinetics of salt ions between the bulk and an ion cloud surrounding the WLMs yielding, , where Keq is the association/dissociation constant, nsurf is the molar surfactant concentration, b is the molar excluded volume, M the WLM molar mass, Θs-s is the salt-surfactant ratio and Θ is the salt-surfactant ratio where the interactions are solely determined by the excluded volume. The ratio b/M2 is independent of WLM contour length. The exponent ϑ is found to be approximately 5/4 in agreement with polymer scaling laws for the semi-dilute regime in good solvents.

16.
Langmuir ; 31(30): 8228-34, 2015 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-26151726

RESUMO

Wormlike or threadlike structures with local cylindrical geometry are abundantly found in nature and technical products. A thorough structural characterization in the bulk for a whole ensemble, however, is difficult. The inherent semiordered nature of the tortuous large-scale structure and especially the quantification of branching renders an assessment difficult. In the present work we introduce a hybrid function expressing the scattering intensities for X-rays, neutrons, or light in the small-angle regime for this system. The function is termed "hybrid" because it employs terms from different approaches. The large-scale structure is described via a Guinier term as well as a concomitant power-law expression in momentum transfer q taken from the so-called unified function. The local cylindrical shape, however, is taken into account through a form factor for cylinders from rigid-body modeling. In principle, the latter form factor can be replaced by an expression for any other regular body so that the new hybrid function is a versatile tool for studying hierarchical structures assembled from uniform subunits. The appropriateness and capability of the new function for cylindrical structures is exemplified using the example of a wormlike micellar system.


Assuntos
Betaína/análogos & derivados , Dodecilsulfato de Sódio/análogos & derivados , Tensoativos/química , Betaína/química , Micelas , Dodecilsulfato de Sódio/química
17.
Zhonghua Yan Ke Za Zhi ; 51(12): 907-11, 2015 Dec.
Artigo em Zh | MEDLINE | ID: mdl-26888272

RESUMO

OBJECTIVE: To report the clinical characteristics, neuto-imaging and prognosis of cavernous hemangioma of the optic chiasm. METHODS: Retrospective data analysis was conducted in 8 patients from Beijing Tongren Hospital and Beijing Tiantan Hospital. Patients' clinical characteristics, neuroimaging and prognosis were assessed. RESULTS: There were eight patients aging from 16-58 years old including 3 females and 5 males. The median age was 39.5 years. From the time of onset to diagnosis, the shortest time was 25 days and the longest was 2 years and 4 months. Clinical characteristics of 8 cases were analyzed. Among 8 cases, 3 patients had acute course, 3 patient had chronic course with acute exacerbation and 2 patients had chronic course. All patients presented with decreased visual acuity and/or visual field defect and 3 cases had headache. The most common initial manifestation was decreased visual acuity and/or visual field defect (4 cases). Only 4 cases were diagnosed cavernous hemangioma of the optic chiasm before surgery. The hemangioma was total resected in 6 patients and other two got partly removed. Visual function was improved in 4 cases after surgery. MRI showed mixed signal. CONCLUSIONS: All patients presented decreased visual acuity and/or visual field defect, often accompanied with headache. It can be misdiagnosed at early stage. MRI may be helpful to the diagnosis. Complete resection at early stage may improve the visual function.


Assuntos
Hemangioma Cavernoso/diagnóstico , Quiasma Óptico , Neoplasias do Nervo Óptico/diagnóstico , Adolescente , Adulto , Erros de Diagnóstico , Feminino , Hemangioma Cavernoso/complicações , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias do Nervo Óptico/complicações , Prognóstico , Estudos Retrospectivos , Fatores de Tempo , Transtornos da Visão/etiologia , Visão Ocular , Acuidade Visual
18.
J Neuroophthalmol ; 34(2): 169-72, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24423600

RESUMO

Castleman disease is a rare lymphoproliferative disorder that has many presentations ranging from unifocal or multifocal mass lesions to a monoclonal gammopathy. It has features that may overlap with osteosclerotic myeloma or POEMS (polyneuropathy, organomegaly, endocrinopathy, M protein, skin changes) syndrome. We report a patient with papilledema, enlarged lymph nodes, and monoclonal IgG, who subsequently developed a polyneuropathy. Biopsy of enlarged mediastinal lymph nodes confirmed the diagnosis of Castleman disease.


Assuntos
Hiperplasia do Linfonodo Gigante/fisiopatologia , Papiledema/diagnóstico , Adulto , Antineoplásicos/uso terapêutico , Ciclofosfamida/uso terapêutico , Doxorrubicina/uso terapêutico , Feminino , Humanos , Linfonodos/patologia , Imageamento por Ressonância Magnética , Nervo Óptico/diagnóstico por imagem , Nervo Óptico/patologia , Papiledema/tratamento farmacológico , Prednisolona/uso terapêutico , Radiografia , Tomógrafos Computadorizados , Vincristina/uso terapêutico
19.
Heliyon ; 10(12): e33263, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39022043

RESUMO

Background: There is no consensus on the timing of immunotherapeutic strategies for the first-episode anti-myelin oligodendrocyte glycoprotein-IgG (MOG-IgG) associated disorders (MOGAD) presenting with isolated optic neuritis (ON). Objective: To investigate the optimal timing of intravenous methylprednisolone therapy (IVMP) and necessity of immunosuppressive therapy for the first-episode isolated MOG-IgG associated ON (iMOG-ON). Methods: Adult patients with the first-episode iMOG-ON were enrolled. Primary outcomes were best-corrected visual acuity (BCVA) at last follow-up (i.e. final BCVA) and relapse, and their predictors were assessed by multivariate analysis. Results: 62 patients were included. Logistic regression analysis revealed BCVA at the time of IVMP (odds ratio: 0.463 (95 % confidence interval (CI) 0.310-0.714) was a factor predictive of regaining a final BCVA of 0.0 logMAR vision, and its Youden optimal criterion was <0.175 logMAR by plotting the receiver operating characteristic curve. The time-dependent cox proportional hazards model exhibited MMF therapy was not associated with a high likelihood of relapse-free survival (HR = 1.099, 95 % CI 0.892-1.354, P = 0.376) after adjusting for age of onset, gender, and baseline MOG serum titers. Similar analysis exhibited evidently negative association between high MOG-IgG serum titers at baseline and relapse-free survival after adjusting for age of onset, gender, and MMF therapy (HR = 0.339, 95 % CI 0.155-0.741, P = 0.007). Conclusions: During the first episode of iMOG-ON, the optimal timing of IVMP may be a short timeframe before visual acuity decreasing to 0.175 logMAR, and MMF therapy may not be recommended for patients with low MOG-IgG serum titers. Further long-term follow-up studies are required to validate these findings.

20.
Adv Mater ; 36(39): e2406653, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39113338

RESUMO

The solution aggregation structure of conjugated polymers is crucial to the morphology and resultant optoelectronic properties of organic electronics and is of considerable interest in the field. Precise characterizations of the solution aggregation structures of organic photovoltaic (OPV) blends and their temperature-dependent variations remain challenging. In this work, the temperature-dependent solution aggregation structures of three representative high-efficiency OPV blends using small-angle X-ray/neutron scattering are systematically probed. Three cases of solution processing resiliency are elucidated in state-of-the-art OPV blends. The exceptional processing resiliency of high-efficiency PBQx-TF blends can be attributed to the minimal changes in the multiscale solution aggregation structure at elevated temperatures. Importantly, a new parameter, the percentage of acceptors distributed within polymer aggregates (Ф), for the first time in OPV blend solution, establishes a direct correlation between Ф and performance is quantified. The device performance is well correlated with the Kuhn length of the cylinder related to polymer aggregates L1 at the small scale and the Ф at the large scale. Optimal device performance is achieved with L1 at ≈30 nm and Ф within the range of 60 ± 5%. This study represents a significant advancement in the aggregation structure research of organic electronics.

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