Gravitational lensing model degeneracies: Is steepness all-important?

In gravitational lensing, steeper mass profiles generically produce longer time delays but smaller magnifications, without necessarily changing the image positions or magnification ratios between different images. This is well known. We find in this paper, however, that even if steepness is fixed, time delays can still have significant model dependence, which we attribute to shape modeling degeneracies. This conclusion follows from numerical experiments with models of 35 galaxy lenses. We suggest that varying and twisting ellipticities, features that are explored by pixelated lens models but not so far by parametric models, have an important effect on time delays.Comment: To appear in Ap

Relación entre pastura (Axonopus catarinensi), lapso de suplementación y crecimiento de vaquillonas en sistema silvopastoril

Pantiu, A.J.; Capellari, A.; Giménez L.I.: Relación entre pastura (Axonopus catarinensi), lapso de suplementación y crecimiento de vaquillonas en sistema silvopastoril. Rev. vet. 26: 1, 22-26, 201

Evaluación del desempeño reproductivo en vacas y vaquillonas cruza índica con protocolo convencional y J-Synch

The objective of this study was evaluate the reproductive performance of índics cross cows and heifers with a conventional protocol and prolonged proestrus in a breeding system at Chaco. Were used 264 cows without calf and 236 heifers with body condition 4 to 6 (scale 1-9). On day 0 a device with 0.5 g of progesterone (DIB) and 2 mg of estradiol benzoate was applied. Animals were randomly distributed into 2 groups: a) conventional: day 8: DIB was withdrawn, D-Cloprostenol (PG) (150μg) and estradiol cypionate (0.5 mg) were administered. Artificial insemination (AI) was performed 48 to 54 hours after withdrawal DIB. b) J-Synch: day 6 DIB was withdrawn, PG (150 μg) and equine chorionic gonadotropin (eCG) (300 or 400 IU) were applied in heifers and cows respectively. The sacro-coccygeal region was painted to determine estrus manifestation, performing AI on the unpainted ones at 60 h and 72 hand in those that were still painted at 72 h in addition to AI buserelin acetate (10 μg) was applied. Ultrasonography diagnosis was made 40 days post-AI. Using Chi 2 test were compared the effect of treatment (conventional vs. J-Synch without eCG) and category (heifer and cow) on the rates of pregnancy and in J-Synch (without vs. with eCG) in addition to estrus manifestation. No association was found between treatments evaluated with reproductive performance with pregnancies of 43% vs 54% in cows and 59% vs 51% in heifers with conventional and J-Synch respectively. In J-Synch of 52 and 56% in cows (54 vs 62%) and heifers (51 vs 50%) without and with eCG respectively. The general pregnancy was 55% in animals that showed estrus and 44% in those that did not. In conclusion, the cows had a tendency to perform better with J-Synch where the use of eCG had no influence on pregnancy.El objetivo de este estudio fue evaluar el desempeño reproductivo en vacas y vaquillonas cruza índica con protocolo convencional y de proestro alargado, en un sistema de cría de Chaco. Se utilizaron 264 vacas secas y 236 vaquillonas, con condición corporal 4 a 6 (escala 1-9). El día 0 se aplicó dispositivo con 0,5 g de progesterona (DIB) y 2 mg de benzoato de estradiol. Los animales se distribuyeron aleatoriamente en 2 grupos: a) convencional (día 8) se retiró DIB, administrándose D-Cloprostenol (PG) (150 μg) y cipionato de estradiol (0,5 mg). La inseminación artificial (IA) se realizó de 48 a 54 h del retiro, b) J-Synch: día 6 se retiró DIB, aplicándose PG (150 μg) y gonadotrofina coriónica equina (eCG: 300 y 400 UI) en vaquillonas y vacas, respectivamente. Se pintó la región sacrocoxígea para determinar manifestación de celo, inseminando a las 60 h y 72 h a las despintadas y en las que seguían pintadas a las 72 h además de IA se aplicó acetato de buserelina (10μg). El diagnóstico por ultrasonografía se efectuó 40 días post-IA. Mediante prueba Chi 2, 3 se comparó el efecto tratamiento (convencional vs J-Synch sin eCG) y categoría (vaquillona y vaca) sobre el porcentaje de preñez y en J-Synch (sin vs con eCG), además de manifestación de celo. No se encontró asociación de los tratamientos evaluados con el desempeño reproductivo, con preñeces del 43% vs 54% en vacas y en vaquillonas del 59% vs 51% con convencional y J-Synch, respectivamente. En J-Synch de 52 y 56%, en vacas (54 vs 62%) y vaquillonas (51 vs 50%) sin y con eCG, respectivamente. La preñez general fue de 55% en animales que manifestaron celo y 44% en aquellos que no lo hicieron. Como conclusión las vacas tuvieron una tendencia a desempeñarse mejor con J-Synch, donde la utilización de eCG no tuvo influencias sobre la preñez

Calidad de carne de novillos 3/8 Braford producidos en Chaco, Argentina

El objetivo del trabajo fue determinar caracteres de calidad de carne en novillos Braford 3/8 producidos en la Provincia de Chaco, Argentina, aplicando tecnología de empaque a fin de evaluar el efecto de la maduración sobre dicho producto. Se evaluaron novillos Braford 3/8 de 2, 4 y 6 dientes, terminados sobre pasturas cultivadas con suplementación estratégica. Se analizaron 4 periodos de maduración: 0, 7, 14 y 21 días en muestras del músculo Longisimus dorsi envasadas al vacío. El color se evaluó por el sistema CIELab, terneza por la cizalla de Warner Braztler, capacidad de retención de agua por porcentajes de pérdidas por cocción y se realizó el análisis proximal para determinar humedad, proteína, grasa y cenizas de las muestras. Para el procesamiento estadístico de los valores de color, retención de agua y terneza, se utilizó el análisis de la variancia en un diseño experimental completamente aleatorizado. Las medias fueron comparadas posteriormente por el test de Duncan. Los datos obtenidos del análisis proximal se analizaron mediante estadística descriptiva. No se registraron diferencias en la luminosidad, índice de rojo e índice de amarillo de la carne para ninguno de los diferentes períodos de maduración (p>0,05). La terneza a los 7 días de maduración fue significativamente inferior que a los 0, 14 y 21 días (p<0,05), al igual que las pérdidas por cocción (p><0,0001). Los análisis químicos revelaron una carne con mediana humedad (72±1,19%), alto tenor proteico (23,08±0,61%) y moderada cantidad de grasa intramuscular (3,27±0,63%), caracteres que se adaptan a los requerimientos actuales del mercado consumidor. Palabras clave: novillo, carne, calidad, maduración, color, retención de agua, terneza. Abstract Rébak, G.I.; Ynsaurralde, A.E.; Capellari, A.; Prester, N.; Vázquez, L.: Meat quality of 3/8 Braford steers bred in Chaco, Argentina. Rev. vet. 23: 2, 95-99, 2012. The aim of this study was to determine meat quality traits in 3/8 Braford steers bred in Chaco, Argentina, using packaging technology to assess the effect of maturation on the product. Braford 3/8 bulls of 2, 4 and 6 teeth finished on cultivated pastures with strategic supplementation, were eval><0,05), al igual que las pérdidas por cocción (p<0,0001). Los análisis químicos revelaron una carne con mediana humedad (72±1,19%), alto tenor proteico (23,08±0,61%) y moderada cantidad de grasa intramuscular (3,27±0,63%), caracteres que se adaptan a los requerimientos actuales del mercado consumidor

Co-occurrence of amyotrophic lateral sclerosis and Leber's hereditary optic neuropathy: is mitochondrial dysfunction a modifier?

N

Diagnostic value of plasma p-tau181, NfL, and GFAP in a clinical setting cohort of prevalent neurodegenerative dementias

Background: Increasing evidence supports the use of plasma biomarkers of neurodegeneration and neuroinflammation to screen and diagnose patients with dementia. However, confirmatory studies are required to demonstrate their usefulness in the clinical setting. Methods: We evaluated plasma and cerebrospinal fluid (CSF) samples from consecutive patients with frontotemporal dementia (FTD) (n = 59), progressive supranuclear palsy (PSP) (n = 31), corticobasal syndrome (CBS) (n = 29), dementia with Lewy bodies (DLB) (n = 49), Alzheimer disease (AD) (n = 97), and suspected non-AD physiopathology (n = 51), as well as plasma samples from 60 healthy controls (HC). We measured neurofilament light chain (NfL), phospho-tau181 (p-tau181), and glial fibrillary acid protein (GFAP) using Simoa (all plasma biomarkers and CSF GFAP), CLEIA (CSF p-tau181), and ELISA (CSF NfL) assays. Additionally, we stratified patients according to the A/T/N classification scheme and the CSF α-synuclein real-time quaking-induced conversion assay (RT-QuIC) results. Results: We found good correlations between CSF and plasma biomarkers for NfL (rho = 0.668, p < 0.001) and p-tau181 (rho = 0.619, p < 0.001). Plasma NfL was significantly higher in disease groups than in HC and showed a greater increase in FTD than in AD [44.9 (28.1–68.6) vs. 21.9 (17.0–27.9) pg/ml, p < 0.001]. Conversely, plasma p-tau181 and GFAP levels were significantly higher in AD than in FTD [3.2 (2.4–4.3) vs. 1.1 (0.7–1.6) pg/ml, p < 0.001; 404.7 (279.7–503.0) vs. 198.2 (143.9–316.8) pg/ml, p < 0.001]. GFAP also allowed discriminating disease groups from HC. In the distinction between FTD and AD, plasma p-tau181 showed better accuracy (AUC 0.964) than NfL (AUC 0.791) and GFAP (AUC 0.818). In DLB and CBS, CSF amyloid positive (A+) subjects had higher plasma p-tau181 and GFAP levels than A− individuals. CSF RT-QuIC showed positive α-synuclein seeding activity in 96% DLB and 15% AD patients with no differences in plasma biomarker levels in those stratified by RT-QuIC result. Conclusions: In a single-center clinical cohort, we confirm the high diagnostic value of plasma p-tau181 for distinguishing FTD from AD and plasma NfL for discriminating degenerative dementias from HC. Plasma GFAP alone differentiates AD from FTD and neurodegenerative dementias from HC but with lower accuracy than p-tau181 and NfL. In CBS and DLB, plasma p-tau181 and GFAP levels are significantly influenced by beta-amyloid pathology

Dementia-related genetic variants in an Italian population of early-onset Alzheimer’s disease

Early-onset Alzheimer’s disease (EOAD) is the most common form of early-onset dementia. Although three major genes have been identified as causative, the genetic contribution to the disease remains unsolved in many patients. Recent studies have identified pathogenic variants in genes representing a risk factor for developing Alzheimer’s disease (AD) and in causative genes for other degenerative dementias as responsible for EOAD. To study them further, we investigated a panel of candidate genes in 102 Italian EOAD patients, 45.10% of whom had a positive family history and 21.74% with a strong family history of dementia. We found that 10.78% of patients carried pathogenic or likely pathogenic variants, including a novel variant, in PSEN1, PSEN2, or APP, and 7.84% showed homozygosity for the ε4 APOE allele. Additionally, 7.84% of patients had a moderate risk allele in PSEN1, PSEN2, or TREM2 genes. Besides, we observed that 12.75% of our patients carried only a variant in genes associated with other neurodegenerative diseases. The combination of these variants contributes to explain 46% of cases with a definite familiarity and 32% of sporadic forms. Our results confirm the importance of extensive genetic screening in EOAD for clinical purposes, to select patients for future treatments and to contribute to the definition of overlapping pathogenic mechanisms between AD and other forms of dementia

Sporadic Creutzfeldt-Jakob disease VM1: phenotypic and molecular characterization of a novel subtype of human prion disease

The methionine (M)-valine (V) polymorphic codon 129 of the prion protein gene (PRNP) plays a central role in both susceptibility and phenotypic expression of sporadic Creutzfeldt-Jakob diseases (sCJD). Experimental transmissions of sCJD in humanized transgenic mice led to the isolation of five prion strains, named M1, M2C, M2T, V2, and V1, based on two major conformations of the pathological prion protein (PrPSc, type 1 and type 2), and the codon 129 genotype determining susceptibility and propagation efficiency. While the most frequent sCJD strains have been described in codon 129 homozygosis (MM1, MM2C, VV2) and heterozygosis (MV1, MV2K, and MV2C), the V1 strain has only been found in patients carrying VV. We identified six sCJD cases, 4 in Catalonia and 2 in Italy, carrying MV at PRNP codon 129 in combination with PrPSc type 1 and a new clinical and neuropathological profile reminiscent of the VV1 sCJD subtype rather than typical MM1/MV1. All patients had a relatively long duration (mean of 20.5 vs. 3.5 months of MM1/MV1 patients) and lacked electroencephalographic periodic sharp-wave complexes at diagnosis. Distinctive histopathological features included the spongiform change with vacuoles of larger size than those seen in sCJD MM1/MV1, the lesion profile with prominent cortical and striatal involvement, and the pattern of PrPSc deposition characterized by a dissociation between florid spongiform change and mild synaptic deposits associated with coarse, patch-like deposits in the cerebellar molecular layer. Western blot analysis of brain homogenates revealed a PrPSc type 1 profile with physicochemical properties reminiscent of the type 1 protein linked to the VV1 sCJD subtype. In summary, we have identified a new subtype of sCJD with distinctive clinicopathological features significantly overlapping with those of the VV1 subtype, possibly representing the missing evidence of V1 sCJD strain propagation in the 129MV host genotype

Sporadic Fatal Insomnia in Europe:Phenotypic features and diagnostic challenges

[Objective] Comprehensively describe the phenotypic spectrum of sporadic fatal insomnia (sFI) to facilitate diagnosis and management of this rare and peculiar prion disorder.[Methods] A survey among major prion disease reference centers in Europe identified 13 patients diagnosed with sFI in the past 20 years. We undertook a detailed analysis of clinical and histopathological features and the results of diagnostic investigations.[Results] Mean age at onset was 43 years, and mean disease duration 30 months. Early clinical findings included psychiatric, sleep, and oculomotor disturbances, followed by cognitive decline and postural instability. In all tested patients, video‐polysomnography demonstrated a severe reduction of total sleep time and/or a disorganized sleep. Cerebrospinal fluid (CSF) levels of proteins 14‐3‐3 and t‐tau were unrevealing, the concentration of neurofilament light protein (NfL) was more consistently increased, and the real‐time quaking‐induced conversion assay (RT‐QuIC) revealed a positive prion seeding activity in 60% of cases. Electroencephalography and magnetic resonance imaging showed nonspecific findings, whereas fluorodeoxyglucose positron emission tomography (FDG‐PET) demonstrated a profound bilateral thalamic hypometabolism in 71% of cases. Molecular analyses revealed PrPSc type 2 and methionine homozygosity at PRNP codon 129 in all cases.[Interpretation] sFI is a disease of young or middle‐aged adults, which is difficult to reconcile with the hypothesis of a spontaneous etiology related to stochastic, age‐related PrP misfolding. The combination of psychiatric and/or sleep‐related symptoms with oculomotor abnormalities represents an early peculiar clinical feature of sFI to be valued in the differential diagnosis. Video‐polysomnography, FDG‐PET, and especially CSF prion RT‐QuIC and NfL constitute the most promising supportive diagnostic tests in vivo.Peer reviewe