Cerebrospinal fluid β-amyloid and phospho-tau biomarker interactions affecting brain structure in preclinical Alzheimer disease

OBJECTIVE

To assess the relationships between core cerebrospinal fluid (CSF) biomarkers and cortical thickness (CTh) in preclinical Alzheimer disease (AD).

METHODS

In this cross-sectional study, normal controls (n = 145) from the Alzheimer's Disease Neuroimaging Initiative underwent structural 3T magnetic resonance imaging (MRI) and lumbar puncture. CSF β-amyloid1-42 (Aβ) and phospho-tau₁₈₁p (p-tau) levels were measured by Luminex assays. Samples were dichotomized using published cutoffs (Aβ(+) /Aβ(-) and p-tau(+) /ptau(-)). CTh was measured by Freesurfer. CTh difference maps were derived from interaction and correlation analyses. Clusters from the interaction analysis were isolated to analyze the directionality of the interaction by analysis of covariance.

RESULTS

We found a significant biomarker interaction between CSF Aβ and CSF p-tau levels affecting brain structure. Cortical atrophy only occurs in subjects with both Aβ(+) and p-tau(+). The stratified correlation analyses showed that the relationship between p-tau and CTh is modified by Aβ status and the relationship between Aβ and CTh is modified by p-tau status. p-Tau-dependent thinning was found in different cortical regions in Aβ(+) subjects but not in Aβ(-) subjects. Cortical thickening was related to decreasing CSF Aβ values in the absence of abnormal p-tau, but no correlations were found in p-tau(+) subjects.

INTERPRETATION

Our data suggest that interactions between biomarkers in AD result in a 2-phase phenomenon of pathological cortical thickening associated with low CSF Aβ, followed by atrophy once CSF p-tau becomes abnormal. These interactions should be considered in clinical trials in preclinical AD, both when selecting patients and when using MRI as a surrogate marker of efficacy.

[Evaluation of conjunctival epithelium of filtering blebs by impression cytology]

PURPOSE

To study the ocular surface in filtering blebs using impression cytology, comparing the bleb side and areas outside the bleb edges.

METHODS

Twelve filtering blebs of 8 patients were included: 4 cases of trabeculectomy without mitomycin C (MMC), 6 cases of trabeculectomy with MMC, and 2 cases of non-penetrating glaucoma surgery. Impression cytology specimens were taken from filtering blebs as well as outside the bleb area. A classification scale from 0 to 3 was used to describe the distribution of epithelial cells and the density of goblet cells. Grade 0 indicated cohesive epithelial cells and abundant goblet cells; and the grade 3 indicated loss of epithelial cohesion and absence of goblet cells.

RESULTS

The mean grade of cytology in filtering blebs was 2.4 ± 0.9, and in the outside bleb area of 0.8 ± 0.3 (P<.001). These differences were independent of the use of MMC (P=.48). The large majority (83%) of filtering blebs showed a decrease in epithelial cohesion and absence of goblet cells. Outside the bleb area, 100% of the cases had cohesive epithelial cells with different grades of goblet cells.

CONCLUSION

The conjunctival epithelium overlying the filtering blebs showed significant changes that consisted of increased intercellular spaces and loss of goblet cells. These increased intercellular spaces could explain the trans-epithelial pathway of aqueous humor. The least amount of mucin due to loss of goblet cells could contribute to increase the risk of infection in filtering blebs.

Randomised, double-blind and placebo-controlled study of the effect of a synbiotic dairy product on orocecal transit time in healthy adult women

OBJECTIVE

To evaluate oro-cecal intestinal transit time (ITT) before and after administration of a dairy product containing Bifidobacterium BB12, Lactobacillus casei CRL 431 and fiber in healthy women.

METHODS

A prospective, randomised, double-blind and cross-over study with a 4-phase design (run-in: time 0 [T0], two intervention periods: time 1 [T1] and time 3 [T3] and a wash-out: time 2, [T2]) was performed. Participants were asked about bowel movement and fiber consumption. ITT was assessed by the carmine red dye method.

RESULTS

Mean age was 40.7 years (n = 102 healthy women; 83 completed the study). In women with initial ITT (IITT) ≥ 48 h consuming the synbiotic product, mean IITT and final ITT (FITT) was 86.9 ± 38.5 h and 51.2 ± 29.8 h (-40.9%), as compared to women consuming the control yoghurt (IITT, 80.8 ± 31.7 h; FITT, 69.5 ± 31.5 h; -13.8%) (p = 0.001). IITT in women with functional constipation consuming the control yoghurt was 57.0 ± 30.0 h; such figure increased 2.8 h after yoghurt consumption (FITT, 59.8 ± 3 0.2 h; +4.9%). Conversely, IITT in women who received the synbiotic yoghurt was 69.0 ± 49.6 h, with a -27.5% decrease 19 h later (FITT, 50.0 ± 27.5 h; p = 0.023). Enteric lactic flora stabilization was significantly higher in women who initially consumed the synbiotic product (p < 0.1).

CONCLUSION

ITT decreased significantly after consumption of the synbiotic product. Such beneficial effect was more evident in women with IITT ≥ 48 h and with functional constipation.

Non-invasive in vivo dermatopathology: identification of reflectance confocal microscopic correlates to specific histological features seen in melanocytic neoplasms

BACKGROUND

Reflectance confocal microscopy (RCM) allows for non-invasive, in vivo evaluation of skin lesions and it has been extensively applied in skin oncology although systematic studies on nevi characterization are still lacking.

OBJECTIVE

The aim of this study was to determine whether reliable RCM correlates to histological features used to diagnose melanocytic neoplasms exist.

METHODS

We blindly evaluated the RCM and histological features of 64 melanocytic neoplasms (19 non-dysplastic nevi, 27 dysplastic nevi, 14 melanomas) and analysed the data using Spearman's rho calculation.

RESULTS

Many histological features can be identified using RCM. Elongated rete ridges corresponded on RCM to edge papillae, whereas flattened rete ridges to several features which involve dermal-epidermal junction disruption. Bridging of junctional nesting (JN) corresponded on RCM to both JN with irregular size/shape and JN with short interconnections. While we could reliably identify dermal melanocytes, the RCM features did not reliably distinguish between benign and concerning dermal melanocytic arrangements, suggesting further refinement of dermal melanocytic RCM features is needed.

CONCLUSION

Reliable correlates for epidermal and junctional histological features used to diagnose melanocytic neoplasms are identifiable on RCM, suggesting harnessing histological criteria may be a reasonable method to move beyond the algorithmic approach.

Confocal microscopy patterns in nonmelanoma skin cancer and clinical applications

Reflectance confocal microscopy is currently the most promising noninvasive diagnostic tool for studying cutaneous structures between the stratum corneum and the superficial reticular dermis. This tool gives real-time images parallel to the skin surface; the microscopic resolution is similar to that of conventional histology. Numerous studies have identified the main confocal features of various inflammatory skin diseases and tumors, demonstrating the good correlation of these features with certain dermatoscopic patterns and histologic findings. Confocal patterns and diagnostic algorithms have been shown to have high sensitivity and specificity in melanoma and nonmelanoma skin cancer. Possible present and future applications of this noninvasive technology are wide ranging and reach beyond its use in noninvasive diagnosis. This tool can also be used, for example, to evaluate dynamic skin processes that occur after UV exposure or to assess tumor response to noninvasive treatments such as photodynamic therapy. We explain the characteristic confocal features found in the main nonmelanoma skin tumors and discuss possible applications for this novel diagnostic technique in routine dermatology practice.

Evaluación del sistema de información rutinaria de la Estrategia Sanitaria de Prevención VIH/sida en un Hospital III-1

Introducción: La OMS y el sistema de información rutinaria en Salud (PRIMS) proponen la existencia de tres determinantes en los sistemas de información en salud (SIRS): los de comportamiento, técnicos, y organizacionales /ambientales, que requieren tener calidad para buen desempeño. Objetivos: Evaluar el sistema de información en Salud (SIRS) del Programa de ITS/VIH/sida en un hospital nivel III-1 de una zona de alta prevalencia. Diseño: Estudio descriptivo. Institución: Instituto de Medicina Tropical Daniel A. Carrión, Facultad de Medicina, UNMSM. Participantes: Personal de Salud involucrado y una muestra representativa de las dos últimas semanas registros del parte diario e historia clínica de las actividades de la ESNPC ITS-VIH/sida. Intervenciones: Se usó herramientas estandarizadas para evaluar estos determinantes. Resultados: Determinantes organizacionales: 60% percibe promoción del uso de la información, 54% su uso en la toma de decisiones, 63% la usó en la resolución de problemas, 52% señaló que recibe retroalimentación, 53% que existe apoyo por la gestión. Calidad técnica: 0,26% omisión de dato; no se encontró inconsistencia de datos en el parte diario; sin embargo, la discordancia entre el parte diario con la Historia clínica fue 52% en edad y 30% en diagnóstico. Competencias: la brecha de lo observado con respecto a lo esperado fue 60% y entre lo autocalificado y lo observado 20%. Conclusiones: El desempeño del SIRS es débil en sus componentes organizacionales, técnicos y del desempeño, debido a registros manuales y datos repetidos en diferentes formularios. Se necesita capacitación para registro, análisis estadístico y su utilización para la toma de decisiones.

Dietary intake of polyphenols and major food sources in an institutionalised elderly population

BACKGROUND

Polyphenols are bioactive compounds widely found in fruit, vegetables and beverages of plant origin. Epidemiological studies have suggested an association between polyphenol intake and health; antioxidant, anti-inflammatory, anti-carcinogenic and other bioactivities may contribute to these beneficially protective effects. To date, most epidemiological studies describing polyphenol intake have been limited by the information available in nutrient databases. The present study aimed to determine the total and individual polyphenol intake among institutionalised elderly people living in Asturias (North of Spain) and to identify the major dietary sources of polyphenol classes and subclasses.

METHODS

The study sample comprised 304 subjects with a mean age of 73.2 years for men and 76.8 years for women. Dietary intake was assessed by means of a food frequency questionnaire. Phenol content was estimated from the Phenol-Explorer database, as developed at the French National Institute for Agricultural Research. The contribution of each food to the total and subgroup intake of polyphenols was calculated as a percentage.

RESULTS

Except for flavonones, total polyphenol intake, groups and subgroups, was higher in men than women. The main polyphenol groups contributing to total polyphenol intake were flavonoids (62%) and phenolic acids (35.5%). We identified red wine, coffee, apples, oranges and green beans as the major food sources providing total polyphenol intake. Flavonoid and lignan intake was lower for those aged >80 years. Smoking habit, red wine consumption, physical activity and a Mediterranean diet score were associated with a greater polyphenol intake.

CONCLUSIONS

The present study provides information on polyphenol intake in an elderly Mediterranean population with a level of detail that has not been achieved previously. The identification of age and lifestyle factors associated with the intake of polyphenols may be useful in future studies regarding polyphenols.

Cognitive neurorehabilitation based on interactive video technology

Cognitive impairment is the main cause of disability in developed societies. New interactive technologies help therapists in neurorehabilitation in order to increase patients' autonomy and quality of life. This work proposes Interactive Video (IV) as a technology to develop cognitive rehabilitation tasks based on Activities of Daily Living (ADL). ADL cognitive task has been developed and integrated with eye-tracking technology for task interaction and patients' performance monitoring.