Características visuales en el albinismo: Revisión sistemática / Visual characteristics in albinism: Systematic review / Características visuais no albinismo: Uma revisão sistemática

El albinismo es una condición compleja, en muchos casos incapacitante, afectando a muchas personas alrededor del mundo, incluso puede conducir a la muerte. Los problemas visuales más comunes que pueden existir en el albinismo con fotofobia son defectos refractivos con medidas considerables, problemas a nivel de fondo de ojo, fotofobia y translucencia de iris. La realidad actual estima que 1 de cada 10.000 personas tienen albinismo y pueden presentar estos problemas visuales. Objetivo. Identificar las características visuales en cada tipo de albinismo presentados en los estudios de Latinoamérica durante el periodo 2014-2022. Metodología. Se realizó una revisión sistemática. Como criterios de inclusión se tomó en cuenta el año de publicación de las fuentes. Se utilizaron los siguientes descriptores de búsqueda en español y en inglés: "albinismo", "tipos de albinismo" y "complicaciones albinismo", "albinism", "albinism types", "albinism issues". Resultados. Fueron seleccionados 22 artículos obtenidos de Google Académico, revistas como pubmed, scielo, Elsevier, tesis, de los cuales y basado en controles de calidad se analizaron 12 fuentes. Conclusión. La mayoría de estudios describen tratamientos posibles para el albinismo. Se resaltan hallazgos clínicos que destacan las características en los tipos de albinismo como lo son problemas a nivel del nervio óptico como la hipoplasia, y disminución de la agudeza visual, nistagmus y en ocasiones el problema de posición compensatoria de cabeza.

Albinism is a complex condition, in many cases disabling, affecting many people around the world, and can even lead to death. The most common visual problems that may exist in albinism with photophobia are refractive defects with considerable measurements, problems at the fundus level, photophobia and iris translucency. Current reality estimates that 1 in 10,000 people have albinism and may present with these visual problems. Objective. To identify the visual characteristics in each type of albinism presented in studies in Latin America during the period 2014-2022. Methodology. A systematic review was performed. The year of publication of the sources was taken into account as inclusion criteria. The following search descriptors were used in Spanish and English: "albinism", "types of albinism" and "albinism complications", "albinism", "albinism types", "albinism issues". Results. Twenty-two articles obtained from Google Scholar, journals such as pubmed, scielo, Elsevier, theses were selected, from which and based on quality controls 12 sources were analyzed. Conclusion. Most studies describe possible treatments for albinism. Clinical findings that highlight the characteristics in the types of albinism such as problems at the level of the optic nerve as hypoplasia, and decreased visual acuity, nystagmus and sometimes the problem of compensatory head position are highlighted.

O albinismo é uma condição complexa e, em muitos casos, incapacitante, que afeta muitas pessoas em todo o mundo e pode até levar à morte. Os problemas visuais mais comuns que podem existir no albinismo com fotofobia são defeitos de refração de tamanho considerável, problemas no nível do fundo do olho, fotofobia e translucidez da íris. A realidade atual estima que 1 em cada 10.000 pessoas tem albinismo e pode apresentar esses problemas visuais. Objetivo. Identificar as características visuais em cada tipo de albinismo apresentado em estudos na América Latina durante o período de 2014 a 2022. Metodologia. Foi realizada uma revisão sistemática. O ano de publicação das fontes foi levado em consideração como critério de inclusão. Foram usados os seguintes descritores de busca em espanhol e inglês: "albinismo", "tipos de albinismo" e "complicações do albinismo", "albinismo", "tipos de albinismo", "questões de albinismo". Resultados. Foram selecionados 22 artigos do Google Scholar, revistas como pubmed, scielo, Elsevier, teses, dos quais 12 fontes foram analisadas com base em controles de qualidade. Conclusão. A maioria dos estudos descreve possíveis tratamentos para o albinismo. Os achados clínicos destacam as características dos diferentes tipos de albinismo, como problemas no nervo óptico, como hipoplasia, diminuição da acuidade visual, nistagmo e, às vezes, problemas compensatórios na posição da cabeça.

Inhibition of low-density lipoprotein oxidation, antioxidative and bile acid-binding capacities of hydrolyzed proteins from carbohydrase-treated oat bran.

This study investigated the valorization of oat bran and the use of its proteins to generate polypeptides with antioxidant and bile acid-binding properties. Ten protein hydrolysates were prepared by treating cellulase (CPI) or Viscozyme (VPI) protein isolates with five proteases. VPI-pepsin was the best peroxyl radical scavenger (497 ± 6-µM Trolox equivalents [TE]/g) while VPI-Flavourzyme quenched hydroxyl radicals (28 ± 0.6) and VPI-pepsin superoxide anion radicals (45.3 ± 6.6%). Hydrolysates, except those produced with pepsin, dose-dependently chelated iron whereas VPI-Protamex had the best copper-chelating capacity (59.83 ± 1.40%). These antioxidative capacities were important in preventing by 50% in vitro copper-induced oxidation of human low-density lipoprotein. Furthermore, due to their aromatic amino acid contents and hydrophobicity, the hydrolysates bound up to 46.3% the bile acids taurodeoxycholate and taurocholate. PRACTICAL APPLICATIONS: The presence of oxidants in foods can damage food molecules and decrease their quality. They are also known to increase the risk of developing chronic conditions like cardiovascular disease. Finding new antioxidant molecules are therefore useful in the management of chronic diseases. Data from this work showed that hydrolyzed oat bran proteins can be useful in stabilizing commercial oil as they reduced the oxidation of peanut oil. Additionally, the protein hydrolysates not only prevented the oxidation of linoleic, a common component of both vegetable oils and biological cell membranes, they also inhibited the oxidation of human LDL cholesterol and chelated bile acids. These hydrolysates can then be further explored as multifunctional ingredients for the development of stable functional food products with potential beneficial effects on the cardiovascular system.

Conversion from Vancomycin Trough Concentration-Guided Dosing to Area Under the Curve-Guided Dosing Using Two Sample Measurements in Adults: Implementation at an Academic Medical Center.

STUDY OBJECTIVE: The optimal pharmacodynamic parameter for the prediction of efficacy of vancomycin is the area under the concentration-time curve (AUC), and current published data indicate that dosing based on vancomycin trough concentrations is an inaccurate substitute. In this study, our objective was to compare the achievement of therapeutic target attainment after switching from a trough-based to an AUC-based dosing strategy as a part of our institution's vancomycin-per-pharmacy protocol. DESIGN: Prospective observational quality assurance study. SETTING: Academic medical center. PATIENTS: A total of 296 hospitalized adults who received vancomycin and monitoring under our institution's vancomycin-per-pharmacy protocol were included in the analysis. The preimplementation retrospective comparison group consisted of 179 patients in whom vancomycin was initiated using a trough-based dosing strategy between November 22, 2017, and January 22, 2018. The postimplementation group included 117 patients in whom vancomycin was initiated using an AUC-based dosing strategy using two-point sampling between June 19, 2018, and July 19, 2018, after hospital-wide implementation of this protocol on June 19, 2018. MEASUREMENTS AND MAIN RESULTS: AUC values were calculated from two vancomycin concentrations (peak and trough). The primary outcome was achievement of therapeutic AUC values (400-800 mg·hr/L) in the postimplementation group or therapeutic trough level values (10-20 mg/L) in the preimplementation group. Only 98 (55%) of 179 initial trough values were therapeutic in the preimplementation group (trough-only dosing method) versus 86 (73.5%) of 117 initial AUC values in the postimplementation group (AUC-based dosing method) (p=0.0014). A lower proportion of supratherapeutic AUC values was observed in the postimplementation group compared with supratherapeutic trough concentrations in the preimplementation group (1.7% vs 18%, p<0.0001). Overall, 62% of patients with initially therapeutic AUC values had subsequent trough value increases of 25% or greater, occurring at a median of 6 days of vancomycin therapy. Nephrotoxicity occurred in 11% of patients in the preimplementation versus 9.4% in the postimplementation group (p=0.70). CONCLUSION: Compared with a trough concentration-based dosing strategy, AUC-based dosing using two-point sampling improved therapeutic target attainment. Implementation is feasible at any hospital that performs vancomycin peak concentration testing and is a workable alternative to using Bayesian software for estimating AUC. This approach should also be directly compared with AUC-based dosing using Bayesian software.

Functionally Distinct Tendons From Elastin Haploinsufficient Mice Exhibit Mild Stiffening and Tendon-Specific Structural Alteration.

Elastic fibers are present in low quantities in tendon, where they are located both within fascicles near tenocytes and more broadly in the interfascicular matrix (IFM). While elastic fibers have long been known to be significant in the mechanics of elastin-rich tissue (i.e., vasculature, skin, lungs), recent studies have suggested a mechanical role for elastic fibers in tendons that is dependent on specific tendon function. However, the exact contribution of elastin to properties of different types of tendons (e.g., positional, energy-storing) remains unknown. Therefore, this study purposed to evaluate the role of elastin in the mechanical properties and collagen alignment of functionally distinct supraspinatus tendons (SSTs) and Achilles tendons (ATs) from elastin haploinsufficient (HET) and wild type (WT) mice. Despite the significant decrease in elastin in HET tendons, a slight increase in linear stiffness of both tendons was the only significant mechanical effect of elastin haploinsufficiency. Additionally, there were significant changes in collagen nanostructure and subtle alteration to collagen alignment in the AT but not the SST. Hence, elastin may play only a minor role in tendon mechanical properties. Alternatively, larger changes to tendon mechanics may have been mitigated by developmental compensation of HET tendons and/or the role of elastic fibers may be less prominent in smaller mouse tendons compared to the larger bovine and human tendons evaluated in previous studies. Further research will be necessary to fully elucidate the influence of various elastic fiber components on structure-function relationships in functionally distinct tendons.

Chemical Tools of Octopus maya during Crab Predation Are Also Active on Conspecifics.

Octopus maya is a major socio-economic resource from the Yucatán Peninsula in Mexico. In this study we report for the first time the chemical composition of the saliva of O. maya and its effect on natural prey, i.e. the blue crab (Callinectes sapidus), the crown conch snail (Melongena corona bispinosa), as well as conspecifics. Salivary posterior glands were collected from octopus caught by local fishers and extracted with water; this extract paralyzed and predigested crabs when it was injected into the third pereiopod. The water extract was fractionated by membrane ultrafiltration with a molecular weight cut-off of 3 kDa leading to a metabolic phase (>3 kDa) and a neurotoxic fraction (<3 kDa). The neurotoxic fraction injected in the crabs caused paralysis and postural changes. Crabs recovered to their initial condition within two hours, which suggests that the effects of the neurotoxic fraction were reversible. The neurotoxic fraction was also active on O. maya conspecifics, partly paralyzing and sedating them; this suggests that octopus saliva might be used among conspecifics for defense and for reduction of competition. Bioguided separation of the neurotoxic fraction by chromatography led to a paralysis fraction and a relaxing fraction. The paralyzing activity of the saliva was exerted by amino acids, while the relaxing activity was due to the presence of serotonin. Prey-handling studies revealed that O. maya punctures the eye or arthrodial membrane when predating blue crabs and uses the radula to bore through crown conch shells; these differing strategies may help O. maya to reduce the time needed to handle its prey.

Cost-effectiveness of a novel blood-pool contrast agent in the setting of chest pain evaluation in an emergency department.

OBJECTIVE: We evaluated three diagnostic strategies with the objective of comparing the current standard of care for individuals presenting acute chest pain and no history of coronary artery disease (CAD) with a novel diagnostic strategy using an emerging technology (blood-pool contrast agent [BPCA]) to identify the potential benefits and cost reductions. MATERIALS AND METHODS: A decision analytic model of diagnostic strategies and outcomes using a BPCA and a conventional agent for CT angiography (CTA) in patients with acute chest pain was built. The model was used to evaluate three diagnostic strategies: CTA using a BPCA followed by invasive coronary angiography (ICA), CTA using a conventional agent followed by ICA, and ICA alone. RESULTS: The use of the two CTA-based triage tests before ICA in a population with a CAD prevalence of less than 47% was predicted to be more cost-effective than ICA alone. Using the base-case values and a cost premium for BPCA over the conventional CT agent (cost of BPCA ≈ 5× that of a conventional agent) showed that CTA with a BPCA before ICA resulted in the most cost-effective strategy; the other strategies were ruled out by simple dominance. The model strongly depends on the rates of complications from the diagnostic tests included in the model. In a population with an elevated risk of contrast-induced nephropathy (CIN), a significant premium cost per BPCA dose still resulted in the alternative whereby CTA using BPCA was more cost-effective than CTA using a conventional agent. A similar effect was observed for potential complications resulting from the BPCA injection. Conversely, in the presence of a similar complication rate from BPCA, the diagnostic strategy of CTA using a conventional agent would be the optimal alternative. CONCLUSION: BPCAs could have a significant impact in the diagnosis of acute chest pain, in particular for populations with high incidences of CIN. In addition, a BPCA strategy could garner further savings if currently excluded phenomena including renal disease and incidental findings were included in the decision model.

Intravenous delivery of targeted liposomes to amyloid-ß pathology in APP/PSEN1 transgenic mice.

Extracellular amyloid-ß (Aß) plaques and intracellular neurofibrillary tangles constitute the major neuropathological hallmarks of Alzheimer's disease (AD). It is now apparent that parenchymal Aß plaque deposition precedes behavioral signs of disease by several years. The development of agents that can target these plaques may be useful as diagnostic or therapeutic tools. In this study, we synthesized an Aß-targeted lipid conjugate, incorporated it in stealth liposomal nanoparticles and tested their ability to bind amyloid plaque deposits in an AD mouse model. The results show that the particles maintain binding profiles to synthetic Aß aggregates comparable to the free ligand, and selectively bind Aß plaque deposits in brain tissue sections of an AD mouse model (APP/PSEN1 transgenic mice) with high efficiency. When administered intravenously, these long circulating nanoparticles appear to cross the blood-brain barrier and bind to Aß plaque deposits, labeling parenchymal amyloid deposits and vascular amyloid characteristic of cerebral amyloid angiopathy.

Computed tomography imaging of primary lung cancer in mice using a liposomal-iodinated contrast agent.

PURPOSE: To investigate the utility of a liposomal-iodinated nanoparticle contrast agent and computed tomography (CT) imaging for characterization of primary nodules in genetically engineered mouse models of non-small cell lung cancer. METHODS: Primary lung cancers with mutations in K-ras alone (Kras(LA1)) or in combination with p53 (LSL-Kras(G12D);p53(FL/FL)) were generated. A liposomal-iodine contrast agent containing 120 mg Iodine/mL was administered systemically at a dose of 16 µl/gm body weight. Longitudinal micro-CT imaging with cardio-respiratory gating was performed pre-contrast and at 0 hr, day 3, and day 7 post-contrast administration. CT-derived nodule sizes were used to assess tumor growth. Signal attenuation was measured in individual nodules to study dynamic enhancement of lung nodules. RESULTS: A good correlation was seen between volume and diameter-based assessment of nodules (R(2)>0.8) for both lung cancer models. The LSL-Kras(G12D);p53(FL/FL) model showed rapid growth as demonstrated by systemically higher volume changes compared to the lung nodules in Kras(LA1) mice (p<0.05). Early phase imaging using the nanoparticle contrast agent enabled visualization of nodule blood supply. Delayed-phase imaging demonstrated significant differential signal enhancement in the lung nodules of LSL-Kras(G12D);p53(FL/FL) mice compared to nodules in Kras(LA1) mice (p<0.05) indicating higher uptake and accumulation of the nanoparticle contrast agent in rapidly growing nodules. CONCLUSIONS: The nanoparticle iodinated contrast agent enabled visualization of blood supply to the nodules during the early-phase imaging. Delayed-phase imaging enabled characterization of slow growing and rapidly growing nodules based on signal enhancement. The use of this agent could facilitate early detection and diagnosis of pulmonary lesions as well as have implications on treatment response and monitoring.

Data analysis: evaluation of nanoscale contrast agent enhanced CT scan to differentiate between benign and malignant lung cancer in mouse model.

Proposed is a method for statistical analysis for a small sample size, repeated measure experiment with nesting factors. In the original experiment the Student t-test was used for analysis. Using the same data, we modeled the experiment into two groups of mice with benign and malignant primary lung tumors. 4 tumor nodules were selected from each mouse (N= 36). The dependent variables are the volume, diameter, and signal attenuation measured using computed tomography (CT). The measurements are made before injecting the contrast and at 0, 72, and 168 hours after injection. The contrast agent enhances tumor nodule volume and volume differences between benign and malignant tumor nodules measured across time (p < 0.05). The signal attenuation measured across time differentiates between benign and malignant groups (p < 0.05). There is significant correlation between rate of change of volume and diameter of tumor. The advantages of this statistical method are discussed.

Conscious worst case definition for risk assessment, part II: a methodological case study for pesticide risk assessment.

This paper illustrates, by a case study, how to apply the conceptual Worst-Case Definition (WCD) model, developed in the methodological paper in the current journal, by Sørensen et al. (2010-this issue). The case is about eco-toxicological risk assessment of pesticides under Danish conditions. Cumulative aspects are included on a conceptual basis as elements of the worst-case conditions. This defines factors that govern the risk assessment, including location in time and space of risk "hotspots". Two pillars of concern drive the conceptual modelling: (1) What to protect (denoted Protected Units (PUs)) and (2) the reason for increased risk level (denoted Causes of Risks (CRs)). Both PUs and CRs are analysed using hierarchical procedures that facilitate a complete listing of concrete factors governing increased risk for adverse effect due to agricultural usage of pesticide. The factors governing pesticide risk are combined in a context that combines the protection of relevant groupings of organisms with the factors for increased risk level for each of these. Identification of the most important relations between defined types of PUs and CRs is illustrated using expert knowledge. Existing databases are used to form spatial distributed risk indicators as estimators for a selection of important relations between PUs and CRs. This paper illustrates how the WCD model can break down the complex issue of uncertainty into fractions that are more open for evaluations. Finally, it shows application of risk indicators in a multi-criterion analysis using respectively self organizing mapping and partial order technique in a comparative analysis that highlights critical aspects of uncertainty, due to the ambiguity between single risk indicator rankings.

A fuzzy ARTMAP-based quantitative structure-property relationship (QSPR) for the Henry's law constant of organic compounds.

Quantitative structure-property relationships (QSPRs) for estimating a dimensionless Henry's Law constant of organic compounds at 25 degrees C were developed based on a fuzzy ARTMAP and back-propagation neural networks using a heterogeneous set of 495 organic compounds. A set of molecular descriptors developed from PM3 semiempirical MO-theory and topological descriptors (second-order molecular connectivity index) were used as input parameters to the neural networks. Quantum chemical input descriptors included average molecular polarizability, dipole moments (total point charge, total hybridization, and total sum), ionization potential, and heat of formation. The fuzzy ARTMAP/QSPR correlated Henry's Law constant for -6.72

Fuzzy ARTMAP and back-propagation neural networks based quantitative structure-property relationships (QSPRs) for octanol-water partition coefficient of organic compounds.

Quantitative structure-property relationships (QSPRs) for estimating the logarithm octanol/water partition coefficients, logK(ow), at 25 degrees C were developed based on fuzzy ARTMAP and back-propagation neural networks using a heterogeneous set of 442 organic compounds. The set of molecular descriptors were derived from molecular connectivity indices and quantum chemical descriptors calculated from PM3 semiempirical MO-theory. Quantum chemical input descriptors include average polarizability, dipole moments, exchange energy, total electrostatic interaction energy, total two-center energy, and ionization potential. The fuzzy ARTMAP/QSPR performed, for a logK(ow) range of -1.6 to 7.9, with average absolute errors of 0.03 and 0.14 logK(ow) for the overall data and test sets, respectively. The optimal 12-11-1 back-propagation/QSPR model, for the same range of logK(ow), exhibited larger average absolute errors of 0.23 and 0.27 logK(ow) for the test and validation data sets, respectively, over the same range of logK(ow) values. The present results with the fuzzy ARTMAP-based QSPR are encouraging and suggest that high performance logK(ow) QSPR that encompasses a wider range of chemical groups could be developed, following the present approach, by training with a larger heterogeneous data set.

Análisis de las fungurias en seis hospitales venezolanos / Analisys of the fungurias in six hospitals venezuelan

Las infecciones urinarias de etiología micótica están en aumento en las últimas décadas. Para conocer la etiología, frecuencia, enfermedades subyacentes y factores predisponentes asociados a las fungurias en Venezuela, se revisaron protocolizadamente en forma restrospectiva y prospectiva los archivos de los laboratorios de Microbiología clínica de seis hospitales de tres ciudades de Venezuela, por un período de 24 meses. De un total de 23644 urocultivos procesados se aislaron microorganismos en 6128 (26 por ciento), y hongos en 487 (2 por ciento del total y 8 por ciento de los positivos), el 90 por ciento (441) correspondieron a especies de Candida: Candida albicans, 218 (48 por ciento); Candida no albicans, 231 (52 por ciento); dentro de este último grupo se indentificaron hasta especies 95 cepas encontrando con mayor frecuencia, C. tropicalis, 53 por ciento; C. parapsilosis, 11 por ciento; C. guillermondii, 11; C. krusei, 4; C. pseudotropicalis, 4; C. sake, 4; C. ciferrii, 2 por ciento; y otras, 4 por ciento. Con menor frecuencia se aisló Torulopsis glabrata, 17 y levaduras sin identificar, 26. Las enfermedades primarias en 405 pacientes con información fueron: cirugía reciente, 117 (29 por ciento); diabete mellitus, 64 (16 por ciento); cáncer, 50 (12 por ciento); politraumatismos, 36 (9 por ciento); fiebre de origen desconocido, 21 (5 por ciento); SIDA, 13 (3 por ciento); transplante de órganos, 9 (2 por ciento). Los factores predisponentes fueron: antibióticos de amplio espectro, 312 (77 por ciento); catéteres urinarios, 240 (60 por ciento); nutrición parenteral, 123 (30 por ciento); neutropenia, 27 (7 por ciento). Las fungurias representaron un porcentaje importante de los urocultivos positivos en la serie estudiada, los diagnósticos primarios y los factores predisponentes son similares a los encontrados en la literatura