Pion form factor in the Kroll-Lee-Zumino model

The renormalizable Abelian quantum field theory model of Kroll, Lee, and Zumino is used to compute the one-loop vertex corrections to the tree-level, Vector Meson Dominance (VMD) pion form factor. These corrections, together with the known one-loop vacuum polarization contribution, lead to a substantial improvement over VMD. The resulting pion form factor in the space-like region is in excellent agreement with data in the whole range of accessible momentum transfers. The time-like form factor, known to reproduce the Gounaris-Sakurai formula at and near the rho-meson peak, is unaffected by the vertex correction at order $\cal{O}$(g_\rpp^2).Comment: Revised version corrects a misprint in Eq.(1

Global Prevalence of Fuchs Endothelial Corneal Dystrophy (FECD) in Adult Population: A Systematic Review and Meta-Analysis

Purpose. To evaluate the global prevalence of Fuchs endothelial corneal dystrophy (FECD). Design. Systematic review and meta-analysis. Methods. A systematic electronic literature search was conducted on PubMed/MedLine, Cochrane Library, and Google Scholar, in order to select papers analysing the prevalence rate of FECD. Two authors independently conducted the electronic search. After removal of duplicates, title and abstract screening, and full-text analysis, data from selected articles were archived in a customized Excel spreadsheet. Risk of bias assessment was performed using the Joanna Briggs Institute Prevalence Critical Appraisal Tool. Meta-analysis was conducted using R (version 1.4.1106, package "meta"). Results. A total of 6660 eligible articles were retrieved from the initial electronic search. Only 4 original works were included in the qualitative and quantitative analysis. Of the 4746 patients included in this meta-analysis (i.e., 2232 male (M) and 2322 female (F)), we retrieved 269 FECD cases (81 M; 188 F), with a pooled prevalence estimates of 7.33% (95% CI: 4.08-12.8%). Statistically significant gender-related differences in the prevalence of FECD emerged by the analysis (OR: 2.22; 95% CI: 1.66-2.96, p=0.0016). While the total number of people aged >30 years with FECD is nowadays estimated at nearly 300 million, an increase of 41.7% in the number of FECD-affected patients is expected by 2050, when the overall figure is supposed to rise up to 415 million. Conclusion. This study provides a reliable figure of the present and future epidemiological burden of FECD globally, which might be useful for the design of FECD screening, treatment, rehabilitation, and related public health strategies

Combined use of coenzyme Q10 and citicoline: A new possibility for patients with glaucoma

Glaucoma is the leading cause of irreversible blindness worldwide. Several risk factors have been involved in the pathogenesis of the disease. By now, the main treatable risk factor is elevated intraocular pressure. Nevertheless, some patients, whose intraocular pressure is considered in the target level, still experience a progression of the disease. Glaucoma is a form of multifactorial ocular neurodegeneration with complex etiology, pathogenesis, and pathology. New evidence strongly suggests brain involvement in all aspects of this disease. This hypothesis and the need to prevent glaucomatous progression led to a growing interest in the pharmacological research of new neuroprotective, non-IOP-lowering, agents. The aim of this paper is to report evidence of the usefulness of Coenzyme Q10 and Citicoline, eventually combined, in the prevention of glaucomatous neurodegeneration

Automatic Segmentation of Posterior Pole Retinal Layers In Patients with Early Stage Glaucoma Using Spectral Domain Optical Coherence Tomography

Purpose: To measure Ganglion Cell Layer (GCL) and Retinal Nerve Fiber Layer (RNFL) thickness of the retinal posterior pole in patients with early stage primary open-angle glaucoma (POAG) using the new automatic segmentation technology of spectral domain optical coherence tomograph (SD-OCT). Methods: 37 clinical records of patients with early glaucoma (grade 1 to 2 according to the Glaucoma Staging System 2) and 40 age and sex-matched controls were considered in this case-control observational retrospective study. Automated segmentation of GCL and RNFL was performed in one randomly selected eye from the electronic OCT records of each participant using the new Spectralis SD-OCT segmentation technology (Heidelberg Engineering, Inc., Heidelberg, Germany). Thickness of different retinal layers was obtained from each Posterior Pole volumetric scan. Measurements of the peripapillary RNFL thickness (pRNFLt) were also obtained and then compared with those of posterior pole RNFL thickness (ppRNFLt). Results: Both GCL and RNFL were significantly thinner at the retinal posterior pole in the POAG group as compared to the control group (p<0,0001). Furthermore, pRNFLt was significantly thinner in the glaucoma group as opposed to the control group (p<0,0001). Measurements of pRNFLt were significantly correlated with those of the ppRNFLt (Pearson’s coefficient r=0.863). Conclusions: The new Spectralis SD-OCT automatic segmentation tool may be useful in evaluating structural damage in patients with early glaucoma, by providing complementary measurements to the clinical assessment of glaucoma that could be used in conjunction with other relevant parameters in the diagnosis and the evaluation of the progression of the disease

Lax eyelid condition (LEC) and floppy eyelid syndrome (FES) prevalence in obstructive sleep apnea syndrome (OSA) patients: a systematic review and meta-analysis

Purpose: Lax eyelid condition (LEC) and floppy eyelid syndrome (FES) represent two distinct conditions which have been associated with several ocular and systemic comorbidities. The main aim of this systematic review and meta-analysis is to explore the available literature to estimate the prevalence rate of LEC and FES in obstructive sleep apnea (OSA). Methods: The protocol of this systematic review and meta-analysis has been registered in PROSPERO. Four electronic databases (PubMed/MEDLINE, Google Scholar, Cochrane Library, Web of Science) were searched from inception to December 24, 2021. A random intercept logistic regression model was carried out for the analysis of overall proportions. Odds ratio and mean difference were reported as measures of the effect size in the presence of binary and continuous outcomes, respectively. The estimated numbers of LEC/FES patients in OSA were calculated by multiplying the prevalence rate determined by our random-effects model and the corresponding Benjafield et al.’s population prospect. Results: We included 11 studies comprising 1225 OSA patients of whom 431 and 153 affected by LEC and FES, respectively. Our model estimated a pooled prevalence rate for LEC and FES in OSA patients of 40.2% (95%CI: 28.6–53.1%) and of 22.4% (95%CI: 13.8–34.2%), respectively. The number of LEC/FES affected individuals among OSA patients is expected to peak up to 376 and to 210 million, respectively. OSA patients appeared to have a 3.4 (95%CI: 2.2–5.2) and a 3.0 (95%CI: 1.7–5.5) increased risk of developing LEC and FES than the healthy counterpart. Conclusion: Prevalence of LEC and FES is higher in OSA-affected patients compared to controls. More studies are warranted to investigate the mechanisms leading to the development of LEC and/or FES in OSA patients, as well as the feasibility of the adoption of these clinical findings as screening tools for OSA

Subclinical signs of retinal involvement in hereditary angioedema

To explore retinal abnormalities using spectral domain optical coherence tomography (SD‐OCT) and OCT‐angiography (OCT‐A) in a highly selective cohort of patients with type I hereditary angioedema (HAE). This prospective case‐control study included 40 type I HAE patients and 40 age‐/sex‐matched healthy subjects (HC). All participants underwent SD‐OCT‐scanning of retinal posterior pole (PP), peripapillary retinal nerve fiber layer (pRNFL), and optic nerve head (ONH). Superficial/deep capillary density was analyzed by OCT‐A. A total of 80 eyes from 40 HAE and 40 eyes from HC were evaluated. The pRNFL was thicker in HAE than in HC in nasal superior (p &lt; 0.0001) and temporal quadrants (p = 0.0005 left, p = 0.003 right). The ONH thickness in HAE patients was greater than in HC in the nasal (p = 0.008 left, p = 0.01 right), temporal (p = 0.0005 left, p = 0.003 right), temporal inferior (p = 0.007 left, p = 0.0008 right), and global (p = 0.005 left, p = 0.007 right) scans. Compared to HC, HAE showed a lower capillary density in both superficial (p = 0.001 left, p = 0.006 right) and deep (p = 0.008 left, p = 0.004 right) whole images, and superficial (p = 0.03 left) and deep parafoveal (p = 0.007 left, p = 0.005 right) areas. Our findings documented subclinical retinal abnormalities in type I HAE, supporting a potential role of the retinal assessment by SD‐ OCT/OCT‐A as a useful tool in the comprehensive care of HAE patients

Tomografia por impedância elétrica e seus possíveis usos na agropecuária.

bitstream/CNPDIA/10189/1/PA26_98.pd

Lindane and Endosulfan Sulfate Isomers in Crassostrea virginica (Gmelin, 1791) Oyster Populations in Lagoon Systems from Central Gulf of Mexico

The aim of this study was to determine Lindane and Endosulfan Sulfate isomers in Crassostrea virginica oyster populations (Gmelin, 1791) in the Mandinga and Alvarado lagoon systems located in the central Gulf of Mexico. Samples were taken from the main oyster banks of each lagoon system, during the three representative seasons of the region, wet, dry and north winds. By means of free diving, 30 commercial size oysters (7 ± 3 cm) were collected in four oyster banks or stations of the Mandinga lagoon system, totaling 360 organisms, while in the Alvarado lagoon system there were a total of 90 oysters during the annual cycle. Concentration of lindane and endosulfan sulfate isotopes in C. virginica was performed with a gas chromatograph (Thermo Electron Model Trace GC Ultra 115V, Thermo Fisher Scientific Inc©, Monterrey, Nuevo León, México) with an Electron capture detector. Results showed that in the Alvarado Lagoon system mean concentrations of C. virginica oysters for lindane pesticide were 4.11 ± 3.83 ng⋅g-1, whereas for the Mandinga lagoon system, were 8.69 ± 5.15 ng⋅g-1. Endosulfan sulfate showed the highest average concentration in the Mandinga lagoon system with 24.68 ± 1.20 ng ⋅g-1. In addition, the endosulfan sulfate presents differences in its spatial distribution; high concentration levels in the Mandinga lagoon system whereas the lindane heterogeneity at all sampling points in both lagoons. Values of concentrations and relationships between compounds suggest recent contributions that could correspond to the excessive fluctuations of water discharged into the lagoon caused by the atypical rains of the year of sampling. It was concluded that endosulfan sulfate and lindane show concentration in all the points of sampling in both lagoons