Cognitive Speed in Neurodegenerative Disease: Comparing Mean Rate and Inconsistency Within and Across the Alzheimer's and Lewy Body Spectra in the COMPASS-ND Study.

Background: Alzheimer's disease (AD) and Lewy body disease (LBD) are characterized by early and gradual worsening perturbations in speeded cognitive responses. Objective: Using simple and choice reaction time tasks, we compared two indicators of cognitive speed within and across the AD and LBD spectra: mean rate (average reaction time across trials) and inconsistency (within person variability). Methods: The AD spectrum cohorts included subjective cognitive impairment (SCI, n = 28), mild cognitive impairment (MCI, n = 121), and AD (n = 45) participants. The LBD spectrum included Parkinson's disease (PD, n = 32), mild cognitive impairment in PD (PD-MCI, n = 21), and LBD (n = 18) participants. A cognitively unimpaired (CU, n = 39) cohort served as common benchmark. We conducted multivariate analyses of variance and discrimination analyses. Results: Within the AD spectrum, the AD cohort was slower and more inconsistent than the CU, SCI, and MCI cohorts. The MCI cohort was slower than the CU cohort. Within the LBD spectrum, the LBD cohort was slower and more inconsistent than the CU, PD, and PD-MCI cohorts. The PD-MCI cohort was slower than the CU and PD cohorts. In cross-spectra (corresponding cohort) comparisons, the LBD cohort was slower and more inconsistent than the AD cohort. The PD-MCI cohort was slower than the MCI cohort. Discrimination analyses clarified the group difference patterns. Conclusions: For both speed tasks, mean rate and inconsistency demonstrated similar sensitivity to spectra-related comparisons. Both dementia cohorts were slower and more inconsistent than each of their respective non-dementia cohorts.

Data-driven approaches to executive function performance and structure in aging: Integrating person-centered analyses and machine learning risk prediction.

Objective: Executive function (EF) performance and structure in nondemented aging are frequently examined with variable-centered approaches. Person-centered analytics can contribute unique information about classes of persons by simultaneously considering EF performance and structure. The risk predictors of these classes can then be determined by machine learning technology. Using data from the Victoria Longitudinal Study we examined two goals: (a) detect different underlying subgroups (or classes) of EF performance and structure and (b) test multiple risk predictors for best discrimination of these detected subgroups. Method: We used a classification sample (n = 778; Mage = 71.42) for the first goal and a prediction subsample (n = 570; Mage = 70.10) for the second goal. Eight neuropsychological measures represented three EF dimensions (inhibition, updating, shifting). Fifteen predictors represented five domains (genetic, functional, lifestyle, mobility, demographic). Results: First, we observed two distinct classes: (a) lower EF performance and unidimensional structure (Class 1) and (b) higher EF performance and multidimensional structure (Class 2). Second, Class 2 was predicted by younger age, more novel cognitive activity, more education, lower body mass index, lower pulse pressure, female sex, faster balance, and more physical activity. Conclusions: Data-driven modeling approaches tested the possibility of an EF aging class that displayed both preserved EF performance levels and sustained multidimensional structure. The two observed classes differed in both performance level (lower, higher) and structure (unidimensional, multidimensional). Machine learning prediction analyses showed that the higher performing and multidimensional class was associated with multiple brain health-related protective factors. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Visual Analytics for Hypothesis-Driven Exploration in Computational Pathology.

Recent advances in computational and algorithmic power are evolving the field of medical imaging rapidly. In cancer research, many new directions are sought to characterize patients with additional imaging features derived from radiology and pathology images. The emerging field of Computational Pathology targets the high-throughput extraction and analysis of the spatial distribution of cells from digital histopathology images. The associated morphological and architectural features allow researchers to quantify and characterize new imaging biomarkers for cancer diagnosis, prognosis, and treatment decisions. However, while the image feature space grows, exploration and analysis become more difficult and ineffective. There is a need for dedicated interfaces for interactive data manipulation and visual analysis of computational pathology and clinical data. For this purpose, we present IIComPath, a visual analytics approach that enables clinical researchers to formulate hypotheses and create computational pathology pipelines involving cohort construction, spatial analysis of image-derived features, and cohort analysis. We demonstrate our approach through use cases that investigate the prognostic value of current diagnostic features and new computational pathology biomarkers.

Integrating Three Characteristics of Executive Function in Non-Demented Aging: Trajectories, Classification, and Biomarker Predictors.

OBJECTIVE: With longitudinal executive function (EF) data from the Victoria Longitudinal Study, we investigated three research goals pertaining to key characteristics of EF in non-demented aging: (a) examining variability in EF longitudinal trajectories, (b) establishing trajectory classes, and (c) identifying biomarker predictors discriminating these classes. METHOD: We used a trajectory analyses sample (n = 781; M age = 71.42) for the first and second goals and a prediction analyses sample (n = 570; M age = 70.10) for the third goal. Eight neuropsychological EF measures were used as indicators of three EF dimensions: inhibition, updating, and shifting. Data-driven classification analyses were applied to the full trajectory distribution. Machine learning prediction analyses tested 15 predictors from genetic, functional, lifestyle, mobility, and demographic risk domains. RESULTS: First, we observed: (a) significant variability in EF trajectories over a 40-year band of aging and (b) significantly variable patterns of EF decline. Second, a four-class EF trajectory model was observed, characterized with classes differentiated by an algorithm of level and slope information. Third, the highest group class was discriminated from lowest by several prediction factors: more education, more novel cognitive activity, lower pulse pressure, younger age, faster gait, lower body mass index, and better balance. CONCLUSION: First, with longitudinal variability in EF aging, the data-driven approach showed that long-term trajectories can be differentiated into separable classes. Second, prediction analyses discriminated class membership by a combination of multiple biomarkers from demographic, lifestyle, functional, and mobility domains of risk for brain and cognitive aging decline.

Scanning electron microscopy of superficial defects in Twisted files and Reciproc nickel-titanium files after use in extracted molars.

AIM: To evaluate the usage and superficial defects in size 25, 0.08 taper Twisted files (TF) and R25 Reciproc files after root canal instrumentation. METHODOLOGY: One hundred and twenty mandibular molars with root canal curvature, ranging from 15° to 30° and a 4-5 mm radius, were randomly divided into two groups according to single-file instrumentation: size 25, 0.08 taper TF or R25 files. A total of fifteen files per group were evaluated before and after three, six, nine and 12 uses. The instruments were fixed in custom-made holders and photographed using scanning electron microscopy at ×260 to ×1200 magnifications. The presence of superficial defects (plastic deformation, microcracks, fracture, craters, disruption of the cutting edges and blunt edges) was scored from the pre- and post-usage photographs. Chi-squared test was used to analyse differences after usages in both groups individually. Two-way anova was used to analyse differences between both instruments. The level of significance for all analyses was 5%. RESULTS: Superficial defects were observed after the instrumentation of six root canals in the TF group and after the instrumentation of nine root canals in the R25 group. Plastic deformation and disruption of cutting edges were the prevalent defects observed in the TF group, and craters and blunt edges were observed in R25 files. The presence of defects was significantly increased with successive usages in both groups (P < 0.05), but TF had more superficial defects than R25 files (P < 0.001). Dentine debris was observed on all instruments. No instruments fractured. CONCLUSIONS: Instrumentation was possible for six root canals with TF files and nine root canals with R25 files before the presence of superficial defects appeared. Differences in the prevalence and development of superficial defects were observed between the TF and R25 files.

Quistes y tumores de maxilar en niños / Cysts and maxillary tumors in children

Presentamos una revisión clínica,patológica y terapeútica realizada en el hospital del Cáncer,centro de referencia de patología tumoral del país,en el lapso de 17 años(1980-1997)Se estudiaron 39 casos de quistes y tumores del maxilar,cuyos diagnósticos fueron:Quistes dentígeros 7,granuloma reparativo 4,ameloblastoma 4,fibrodisplasia 4,linfoma de Burkitt 9,sarcoma de Ewing 2,hemangiomas 2,mixoma 2,carcinoma mucoepidermoide 1,osteosarcoma 1,tumor de células germinales 1,fibroma osificante 1 y exostósis ósea 1.Todos los pacientes recibieron tratamiento quirúrgico,además de quimioterapia y radioterapia coaduvante en los tumores malignos.Los quistes y tumores benignos tuvieran buena evolución,no así algunos tumores malignos que pese al tratamiento recibido presentaron progresión de la enfermedad

Quistes y tumores de maxilar en niños / Cysts and maxillary tumors in children

Presentamos una revisión clínica,patológica y terapeútica realizada en el hospital del Cáncer,centro de referencia de patología tumoral del país,en el lapso de 17 años(1980-1997)Se estudiaron 39 casos de quistes y tumores del maxilar,cuyos diagnósticos fueron:Quistes dentígeros 7,granuloma reparativo 4,ameloblastoma 4,fibrodisplasia 4,linfoma de Burkitt 9,sarcoma de Ewing 2,hemangiomas 2,mixoma 2,carcinoma mucoepidermoide 1,osteosarcoma 1,tumor de células germinales 1,fibroma osificante 1 y exostósis ósea 1.Todos los pacientes recibieron tratamiento quirúrgico,además de quimioterapia y radioterapia coaduvante en los tumores malignos.Los quistes y tumores benignos tuvieran buena evolución,no así algunos tumores malignos que pese al tratamiento recibido presentaron progresión de la enfermedad

[Clinical and hematological changes in calves infected with Anaplasma marginale]. / Cambios clínicos y hematológicos en becerros infectados con Anaplasma marginale.

Clinical and hematological changes of six Anaplasma marginale (isolated Zulia) inoculated calves (experimental group) and four healthy calves (control group) were studied during twenty and eighty days before and after infection, respectively. The behavior of the four calves used as control group was stable and no significant changes in the parameters analyzed was observed. The experimental group developed the three typical phases of illness. During the prepatent phase, which lasted a mean of 21.2 +/- 2.56 days, the animals were asymptomatic and no significant changes in the hematological values occurred, but a remarkable transitory decrease in number of lymphocytes from 6.5 x 10(6) to 3.3 x 10(6) cells/ml. The infection during the acute phase produced a highly severe effect in two animals, a severe effect in three animals and a mild effect in one. The effects observed were the following: 1) a fast decrease in haematocrite, ranging from 6 to 10%; 2) values of parasitaemia varied from 15 to 48%; 3) a greater body temperature than the control animals (40.5 vs. 38.5 degrees C); 4) a elevated heart frequency, from 60 to 110 beats/min; 5) an increase in the concentration of neotrophiles from 10 x 10(6) to 13 x 10(6) cells/ml; 6) The number of monocytes also augmented from 3 x 10(6) to 6 x 10(6) cells/ml; and 7) an important decrease of weight gain. The natural course of infection was interrupted with oxytetracycline when the haematocrite of the animal lowered to values less or equal to 10%. Then, the animals showed a rapid recovery with an undetectable parasitaemia and concomitant return to basal line of the rest of the parameters.

Monitoreo Cardiopulmonar en Endoscopia Digestiva Alta

La morbimortalidad asociada a la endoscopia digestiva esta en el 0.09 por ciento originada en complicaciones por trauma sobre el tubo digestivo o por premedicacion; sin embargo, poco se conocen sus efectos cardiovasculares y ventilatorios para poder establecer grupos o factores de riesgo, especialmente a la altura de Bogotá, donde los valores de PaO2 son más bajos y su rango es más estrecho. Se realizó un estudio prospectivo en 34 pacientes a quienes se practicó endoscopia alta con monitoría continua de frecuencia respiratoria, saturación de oxígeno por oximetría de oreja, presión media arterial y electrocardiografía continua, preendoscopica, durante el procedimiento y en reposo

Incontinencia pigmenti (Bloch-Sulzberger) asociada a Síndrome de Klippel Feil / Incontinentia pigmenti asociated with Klippel Feil Syndrome

Se presenta el caso de una I.P. asociada a S. de K.F. en una niña de 16 años. Se señalan todas las anomalías que tienen en común ambas entidades y la posibilidad de que algunos casos de la literatura tengan este tipo de asociación no detectado a causa de la corta edad de los pacientes que hace difícil la identificación del cuello corto o del pterigium colli característico del síndrome de K.F. (AU)

Incontinencia pigmenti (Bloch-Sulzberger) asociada a Síndrome de Klippel Feil / Incontinentia pigmenti asociated with Klippel Feil Syndrome

Se presenta el caso de una I.P. asociada a S. de K.F. en una niña de 16 años. Se señalan todas las anomalías que tienen en común ambas entidades y la posibilidad de que algunos casos de la literatura tengan este tipo de asociación no detectado a causa de la corta edad de los pacientes que hace difícil la identificación del cuello corto o del pterigium colli característico del síndrome de K.F.

Sobre una curiosa forma de queratodermia punteada / An interesting form of keratodermia punteada

Se presenta un caso de queratodermia punteada no familiar que por su clínica o su histopatología no se ajusta a ninguno de los casos descriptos en la literatura (AU)

Sobre una curiosa forma de queratodermia punteada / An interesting form of keratodermia punteada

Se presenta un caso de queratodermia punteada no familiar que por su clínica o su histopatología no se ajusta a ninguno de los casos descriptos en la literatura

Suppression of humoral immunity and lymphocyte responsiveness during experimental Trypanosoma cruzi infections.

Ratones C3H/He y C57B1/6 inoculados con 500 tripomastigotes de la cepa Y de T.cruzi muestran durante la fase aguda de la enfermedad, parasitemia, aumento del bazo y ganglios linfaticos asi como parasitos intracelulares en el corazon. Analisis de las celulas presentes en ganglios linfaticos y bazo presenta aumento de celulas IgM e IgG. Cuando la esplenomegalia es mayor, alrededor del dia 17 postinfeccion, los linfocitos esplenicos mostraron un descenso marcado en la respuesta a mitogenos de celulas B y T, antigenos de T. cruzi y celulas formadoras de placas contra globulos rojos de carnero. Celulas de bazo o celulas esplenicas adherentes a plastico, obtenidas de ratones durante la fase aguda de la infeccion suprimen la respuesta a mitogenos de linfocitos normales. Durante la fase cronica, desaparece la parasitemia, los parasitos intracelulares en el corazon y disminuye la esplenomegalia. Estos cambios preceden a la recuperacion de la respuesta a mitogenos y antigenos de T.cruzi en linfocitos esplenicos de C57B1/6.Esta recuperacion es solo parcial en C3H/He, los cuales son mas sensibles a la infeccion. Tambien se encuentra recuperacion de la respuesta humoral durante la fase cronica

Angioqueratoma circunscripto neviforme (Fabry II). / Angiokeratoma circunscriptum naeviformis (Fabry II)

Se presenta el caso de un nino de 5 anos de edad, con angioqueratoma circunscripto neviforme situado en raiz y cara anterior del musculo izquierdo.La histopatologia es caracteristica, con vasos muy superficiales dilatados y un hemangioma cavernoso en la profundidad. Es interesante destacar que el nino padecia epilepsia desde los 5 meses de edad, ya que ambas afecciones porian estar relacionadas

Surco nasal transverso. / Tranversal nasal groove

Se presentan seis casos de surco nasal transverso, en jovenes de 17 a 29 anos de edad y se hace alguna consideracion sobre su probable origen

Correlacion topografica entre las lineas del hombre y las de algunos mamiferos interpigmentarias. / Topographical correlation between the man lineas and some interpigmentary mammals

Se recuerdan las lineas interpigmentarias que presenta el hombre y cuya distribucion no corresponde en todos los casos a dermatomas ni a lineas de Voight. Se estudia la correlacion topografica entre estas lineas y las que aparecen en algunos mamiferos.Vista esta coincidencia, pueden considerarse a las lineas del hombre como uma regresion atavica que repite en el caracteres ya encontrados en animales inferiores.Se aventura la hipotesis de que por su disposicion estas zonas pueden haberse originado como una proteccion natural contra la radiacion solar

Complejo formado por ictiosis, retinitis pigmentaria, obesidad y polidactilia. Consideraciones sobre su diagnostico diferencial. / Complex formed by ichthyosis, pigmentary retinitis, obesity and polydactyly.Considerations on its differential diagnosis

Se presenta el caso de un complejo en una joven de 16 anos que presentaba ictiosis simple, retinitis pigmentaria, polidactilia, nanismo y obesidad.Se resume el diagnostico diferencial con otros sindromes que se asemejan por la presencia en todos ellos de ictiosis y lesiones oculares