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The previously described approach for determination of the relativistic atomic X-ray scattering factors (XRSFs) at the Dirac-Hartree-Fock level [Olukayode et al. (2023). Acta Cryst. A79, 59-79] has been used to evaluate the XRSFs for a total of 318 species including all chemically relevant cations [Greenwood & Earnshaw (1997). Chemistry of the Elements], six monovalent anions (O-, F-, Cl-, Br-, I-, At-), the ns1np3 excited (valence) states of carbon and silicon, and several exotic cations (Db5+, Sg6+, Bh7+, Hs8+ and Cn2+) for which the chemical compounds have been recently identified, thus significantly extending the coverage relative to all the earlier studies. Unlike the data currently recommended by the International Union of Crystallography (IUCr) [Maslen et al. (2006). International Tables for Crystallography, Vol. C, Section 6.1.1, pp. 554-589], which originate from different levels of theory including the non-relativistic Hartree-Fock and correlated methods, as well as the relativistic Dirac-Slater calculations, the re-determined XRSFs come from a uniform treatment of all species within the same relativistic B-spline Dirac-Hartree-Fock approach [Zatsarinny & Froese Fischer (2016). Comput. Phys. Comm. 202, 287-303] that includes the Breit interaction correction and the Fermi nuclear charge density model. While it was not possible to compare the quality of the generated wavefunctions with that from the previous studies due to a lack (to the best of our knowledge) of such data in the literature, a careful comparison of the total electronic energies and the estimated atomic ionization energies with experimental and theoretical values from other studies instils confidence in the quality of the calculations. A combination of the B-spline approach and a fine radial grid allowed for a precise determination of the XRSFs for each species in the entire 0 ≤ sin θ/λ ≤ 6â Å-1 range, thus avoiding the necessity for extrapolation in the 2 ≤ sin θ/λ ≤ 6â Å-1 interval which, as was shown in the first study, may lead to inconsistencies. In contrast to the Rez et al. work [Acta Cryst. (1994), A50, 481-497], no additional approximations were introduced when calculating wavefunctions for the anions. The conventional and extended expansions were employed to produce interpolating functions for each species in both the 0 ≤ sin θ/λ ≤ 2â Å-1 and 2 ≤ sin θ/λ ≤ 6â Å-1 intervals, with the extended expansions offering a significantly better accuracy at a minimal computational overhead. The combined results of this and the previous study may be used to update the XRSFs for neutral atoms and ions listed in Vol. C of the 2006 edition of International Tables for Crystallography.
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In this first of a series of publications, the X-ray scattering factors for neutral atoms are revisited. Using the recently developed DBSR_HF program [Zatsarinny & Froese Fischer (2016). Comput. Phys. Comm. 202, 287-303] the fully relativistic Dirac-Hartree-Fock ground-state wavefunctions for all atoms with Z = 2-118 (He-Og) have been calculated using the extended average level scheme and including both the Breit interaction correction to the electronic motion due to magnetic and retardation effects, and the Fermi distribution function for the description of the nuclear charge density. The comparison of our wavefunctions with those obtained in several previous studies in terms of the total and orbital (spinor) electronic energies, and a number of local and integrated total and orbital properties, confirmed the quality of the generated wavefunctions. The employed dense radial grid combined with the DBSR_HF's B-spline representation of the relativistic one-electron orbitals allowed for a precise integration of the X-ray scattering factors using a newly developed Fortran program SF. Following the established procedure [Maslen et al. (2006). International Tables for Crystallography, Vol. C, Section 6.1.1, pp. 554-589], the resulting X-ray scattering factors have been interpolated in the 0 ≤ sin θ/λ ≤ 2â Å-1 and 2 ≤ sin θ/λ ≤ 6â Å-1 ranges using the recommended analytical functions with both the four- (which is a current convention) and five-term expansions. An exhaustive comparison of the newly generated X-ray scattering factors with the International Union of Crystallography recommended values and those from a number of previous studies showed an overall good agreement and allowed identification of a number of typos and inconsistencies in the recommended quantities. A detailed analysis of the results suggests that the newly derived values may represent an excellent compromise among all the previous studies. The determined conventional interpolating functions for the two sin θ/λ intervals show, on average, the same accuracy as the recommended parametrizations. However, an extension of each expansion by only a single term provides a significant improvement in the accuracy of the interpolated values for an overwhelming majority of the atoms. As such, an updated set of the fully relativistic X-ray scattering factors and the interpolating functions for neutral atoms with Z = 2-118 can be easily incorporated into the existing X-ray diffraction software with only minor modifications. The outcomes of the undertaken research should be of interest to members of the crystallographic community who push the boundaries of the accuracy and precision of X-ray diffraction studies.
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Purpose: Contrast agents applicable for optical coherence tomography (OCT) imaging are rare. The intrascleral aqueous drainage system would be a potential application for a contrast agent, because the aqueous veins are of small diameter and located deep inside the highly scattering sclera. We tested lipid emulsions (LEs) as candidate OCT contrast agents in vitro and ex vivo, including milk and the anesthetic substance Propofol. Methods: Commercial OCT and OCT angiography (OCTA) devices were used. Maximum reflectivity and signal transmission of LE were determined in tube phantoms. Absorption spectra and light scattering was analyzed. The anterior chamber of enucleated porcine eyes was perfused with LEs, and OCTA imaging of the LEs drained via the aqueous outflow tract was performed. Results: All LEs showed a significantly higher reflectivity than water (P < 0.001). Higher milk lipid content was positively correlated with maximum reflectivity and negatively with signal transmission. Propofol exhibited the best overall performance. Due to a high degree of signal fluctuation, OCTA could be applied for detection of LE. Compared with blood, the OCTA signal of Propofol was significantly stronger (P = 0.001). As a proof of concept, time-resolved aqueous angiography of porcine eyes was performed. The three-dimensional (3D) structure and dynamics of the aqueous outflow were significantly different from humans. Conclusions: LEs induced a strong signal in OCT and OCTA. LE-based OCTA allowed the ability to obtain time-resolved 3D datasets of aqueous outflow. Possible interactions of LE with inner eye's structures need to be further investigated before in vivo application.
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Humor Aquoso/fisiologia , Meios de Contraste , Emulsões , Limbo da Córnea/anatomia & histologia , Leite , Propofol , Malha Trabecular/anatomia & histologia , Animais , Angiofluoresceinografia/métodos , Limbo da Córnea/metabolismo , Imagens de Fantasmas , Suínos , Tomografia de Coerência Óptica/métodos , Malha Trabecular/metabolismoRESUMO
PURPOSE: To investigate the feasibility and diagnostic benefit of routinely performed preoperative macular spectral-domain (SD-) optical coherence tomography (OCT) for the detection of macular pathology in patients with normal biomicroscopic funduscopy prior to cataract surgery. METHODS: Prospective, single center study. A total of 162 eyes of 123 consecutive patients referred for cataract surgery with a visual acuity better than 20/100, absence of macular symptoms such as metamorphopsia, no history of previous intravitreal procedures and a normal funduscopic appearance on biomicroscopy underwent an additional SD-OCT-examination prior to cataract surgery. OCT-scans were classified in three categories: normal, degenerative vitreous changes without impact on visual outcome or pathological with potential impact on visual outcome. RESULTS: 80 eyes (49.38%) showed normal OCT-scans. 69 eyes (42.59%) were classified as degenerative vitreous changes without impact on visual outcome and 20 eyes (12.35%) as pathological with potential impact on visual outcome. The indication of cataract surgery or the therapeutic strategy remained unchanged in all patients. In patients with pathological alterations further follow-up examinations were recommended. CONCLUSIONS: Routine SD-OCT-imaging of the macular region in patients prior to cataract surgery was feasible to detect macular pathologies in a considerable number of patients, which remained undiagnosed on biomicroscopic funduscopy. Although OCT-findings did not impact therapeutic strategy in this study, preoperative judgement of the expected visual outcome and patient´s informed consent can improve.
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Catarata/diagnóstico por imagem , Tomografia de Coerência Óptica , Adulto , Idoso , Idoso de 80 Anos ou mais , Catarata/patologia , Extração de Catarata , Membrana Epirretiniana/diagnóstico por imagem , Membrana Epirretiniana/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oftalmoscopia , Estudos Prospectivos , Acuidade VisualRESUMO
This study investigates the impact of impulsivity and the mediating role of disinhibited eating behaviour (DEB) on weight and weight trajectories in a large data set including obese non-treatment seeking individuals (obese control, n = 138) and obese individuals who were either receiving a conventional treatment program (n = 227) or bariatric surgery (n = 123). Data was assessed one, 4 and 9 years after baseline including self-reports for impulsivity and DEB. Results suggest a significant association between impulsivity and body mass index, which is partially mediated by DEB. Longitudinally, the influence of impulsivity on the course of weight after 9 years was fully mediated by DEB in obese control but not in the treatment groups. The results indicate an interplay between impulsivity and DEB with respect to obesity. Further research is needed to clarify how the mediation works and when it exerts its effect, in order to identify those that might profit from a specific (impulsivity-reducing) training. Copyright © 2017 John Wiley & Sons, Ltd and Eating Disorders Association.
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Peso Corporal , Comportamento Alimentar/psicologia , Comportamento Impulsivo , Inibição Psicológica , Obesidade/psicologia , Adulto , Cirurgia Bariátrica , Índice de Massa Corporal , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/cirurgia , Obesidade/terapia , AutorrelatoRESUMO
A Comment on the Letter by Mendoza and Bautista [Phys. Rev. Lett. 118, 163002 (2017)PRLTAO0031-900710.1103/PhysRevLett.118.163002].
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BACKGROUND: Ocular vascular occlusions following intraocular procedures are a rare complication. We report a case series of patients with retinal vascular occlusions or anterior ischemic optic neuropathy (AION) after anterior and posterior segment surgery and demonstrate possible risk factors. METHODS: Observational case series. RESULTS: In ten patients, vascular occlusions were observed within ten weeks after intraocular surgery: branch retinal arterial occlusion (BRAO) (n = 2), central retinal artery occlusion (CRAO) (n = 2), central retinal vein occlusion (CRVO) (n = 1), branch retinal vein occlusion (BRVO) (n = 1), anterior ischemic optic neuropathy (AION) (n = 3), and combined central artery and vein occlusion (n = 1). AION occurred later (27-69 d) than arterial occlusions (14-60 d) or venous occlusions (1-2 d). In all cases, either specific surgical manipulations or general vascular disorders were identified as risk factors. In addition to general cardiovascular risk factors (arterial hypertension n = 6, diabetes mellitus n = 4), internal workup disclosed bilateral stenosis of the carotid arteries (n = 1) and myeloproliferative syndrome (n = 1). CONCLUSION: Vascular occlusions after surgical ocular procedures seem to be more frequent when cardiovascular diseases coexist. Surgical maneuvers and intra- or postoperative pressure changes may act as a triggering mechanism in patients with underlying systemic cardiovascular disorders. Affected patients should undergo thorough internal examination to identify possible underlying diseases.
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PURPOSE: Vascular endothelial growth factor-signaling in human tenon fibroblasts (hTFs) has recently become a target for antifibrotic treatment in glaucoma filtration surgery. The anti-VEGF antibody bevacizumab (BVC) has been shown to increase filtration bleb size. Given the relatively high concentration of BVC needed to obtain an effect, we investigated whether BVC acts through VEGF inhibition or via non-antigen-dependent ways. METHODS: Human tenon fibroblast primary cultures were obtained from strabismus surgery subjects. Under low (0.2%) and high (10%) serum conditions, cells were incubated with BVC, ranibizumab (RNB), aflibercept (AFB), or rituximab (RTX) at different concentrations. Total number of cells and number of dead or proliferating (5-bromo-2-deoxy-uridine-positive) cells were assessed after 24 hours. Concentrations of VEGF-A in cell culture media was measured with ELISA. Intracellular IgG was detected with immunostaining and Western blot analysis. RESULTS: In quiescent hTF culture (0.2% serum) the addition of 5 mg/mL BVC induced widespread cell death. Under proliferative conditions (10% serum), BVC reduced the number of proliferating cells. No such effect was observed with 2.5 mg/mL BVC or with 10 mg/mL AFB or 2.5 mg/mL RNB, although they were equally effective in binding free VEGF-A in the culture media. Instead, the CD20 antibody RTX, which did not bind VEGF, induced hTF death and inhibited proliferation in a BVC-comparable fashion. Bevacizumab, AFB, and RTX were detected intracellularly in a concentration-dependent manner. CONCLUSIONS: The cell death-inducing and antiproliferative effect of 5 mg/mL BVC appeared not to depend on VEGF inhibition. Our data question a direct role of VEGF for hTF survival and proliferation.
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Extreme obesity is associated with severe psychiatric and somatic comorbidity and impairment of psychosocial functioning. Bariatric surgery is the most effective treatment not only with regard to weight loss but also with obesity-associated illnesses. Health-related psychological and psychosocial variables have been increasingly considered as important outcome variables of bariatric surgery. However, the long-term impact of bariatric surgery on psychological and psychosocial functioning is largely unclear. The aim of this study was to evaluate the relationship between the course of weight and psychological variables including depression, anxiety, health-related quality of life (HRQOL), and self-esteem up to 4 years after obesity surgery.By standardized questionnaires prior to (T1) and 1 year (T2), 2 years (T3), and 4 years (T4) after surgery, 148 patients (47 males (31.8 %), 101 females (68.2 %), mean age 38.8 ± 10.2 years) were assessed.On average, participants lost 24.6 % of their initial weight 1 year after surgery, 25.1 % after 2 years, and 22.3 % after 4 years. Statistical analysis revealed significant improvements in depressive symptoms, physical dimension of quality of life, and self-esteem with peak improvements 1 year after surgery. These improvements were largely maintained. Significant correlations between weight loss and improvements in depression, physical aspects of HRQOL (T2, T3, and T4), and self-esteem (T3) were observed.Corresponding to the considerable weight loss after bariatric surgery, important aspects of mental health improved significantly during the 4-year follow-up period. However, parallel to weight regain, psychological improvements showed a slow but not significant decline over time.
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Transtornos de Ansiedade/prevenção & controle , Cirurgia Bariátrica , Transtorno Depressivo/prevenção & controle , Obesidade Mórbida/psicologia , Obesidade Mórbida/cirurgia , Autoimagem , Adulto , Transtornos de Ansiedade/epidemiologia , Índice de Massa Corporal , Estudos de Coortes , Transtorno Depressivo/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida/psicologia , Inquéritos e Questionários , Resultado do Tratamento , Redução de Peso , Adulto JovemRESUMO
BACKGROUND: Mutations of the UDP-N-acetylglucosamine-2-epimerase/N-acetylmannosamine-kinase (GNE)-gene are causally related to GNE myopathy. Yet, underlying pathomechanisms of muscle fibre damage have remained elusive. In sporadic inclusion body myositis (sIBM), the pro-inflammatory cell-stress mediators αB-crystallin and inducible nitric oxide synthase (iNOS) are crucial markers of the disease pathology. METHODS: 10 muscle biopsies from GNE myopathy patients were analyzed for mRNA-expression of markers of cell-stress, inflammation and ß-amyloid and compared to non-myopathic controls. Using double-labeling immunohistochemistry, serial sections of skeletal muscle biopsies were stained for amyloid precursor protein (APP), major histocompatibility complex (MHC)-I, αB-crystallin, neural cell adhesion molecule (NCAM), interleukin (IL)-1ß, ß-amyloid, iNOS, and phosphorylated neurofilament (P-neurofilament) as well as hematoxylin/eosin histochemistry. Corresponding areas of all biopsies with a total of 2,817 muscle fibres were quantitatively assessed for all markers. RESULTS: mRNA-expression of APP, NCAM, iNOS, TNF-α and TGF-ß was higher in GNE myopathy compared to controls, yet this was not statistically significant. The mRNA-expression of APP and αB-crystallin significantly correlated with the expression of several pro-inflammatory and cell-stress-associated markers as NCAM, IL-1ß, TGF-ß, CCL-3, and CCL4. By immunohistochemistry, αB-crystallin and iNOS were co-upregulated and the number of fibres positive for αB-crystallin, NCAM, MHC-I and iNOS significantly correlated with each other. A large fraction of fibres positive for αB-crystallin were double positive for iNOS and vice-versa. Moreover, several fibres with structural abnormalities were positive for αB-crystallin and iNOS. Notably, particularly normal appearing fibres displayed an overexpression of these molecules. CONCLUSIONS: The cell-stress molecules αB-crystallin and iNOS are overexpressed in GNE myopathy muscle and may identify early disease mechanisms. The data help to better understand the pathology of GNE myopathy.