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Data obtained during 4 generations of divergent selection for placental efficiency were used to determine factors influencing survival at farrowing and weaning in litters produced by first-parity females. Data were collected from 193 litters and included records on 2,053 individuals. Farrowing survival (FS) and weaning survival (WS) were considered traits of the piglet and were scored 1 if the individual was alive at a time point or 0 if dead. Estimates of (co)variance components for direct and maternal additive genetic effects for FS and WS were obtained using an animal model and computed with the MTDFREML program. Estimates of direct heritability were 0.16 for FS and 0.18 for WS. Estimates of maternal heritability were 0.14 for FS and 0.10 for WS. Genetic correlation estimates between direct and maternal effects were high and negative for both traits. The direct genetic correlation between FS and WS was 0.92. Variables associated with FS and WS were determined using logistic regression procedures. Birth weight (BRW), placental weight, their interaction, and total born can be used as predictors of survival at farrowing in the absence of estimates of genetic merit for survival. The same model, excluding total number born, was the best model for predicting WS. In the presence of BRW information, placental efficiency did not improve the prediction of survival. While it was clearly disadvantageous for a piglet to be below the litter mean in BRW, being above the mean did not provide a substantial advantage in survival. Results from this analysis suggest that it is possible to select for increased survival at farrowing and at weaning. Information on a piglet's BRW, placental weight, litter average BRW, and deviation from litter average BRW can be used to optimize those values at levels resulting in high survival probability. Key words: birth weight, genetic parameter, pig, survival

The objectives of this study were to estimate response to divergent selection for an index of placental efficiency in swine, and to evaluate the effect of placental efficiency on litter size. The selection index (SI) included total born (TB), birth weight (BRWT), and placental weight (PW), and was designed to increase in the high line (H) or decrease in the low line (L) the efficiency of the placental function (PE), defined as the ratio BRWT:PW. (Co)variance components were estimated for direct and maternal additive effects by using an animal model with MTDFREML procedures. Estimated breeding values were calculated by using records on individual BRWT (n = 2,111), PW (n = 2,006), PE (n = 1,677), and SI (n = 1,677). Litter traits were evaluated using records on 193 litters. The model included the fixed effects of contemporary group for all traits, with the addition of sex for individual traits and parity for litter traits. Litter was fitted as an uncorrelated random effect for all traits, and TB was used as a linear and quadratic covariate for BRWT, PW, and PE. Direct heritability estimates from single-trait models were 0.03, 0.25, 0.18, 0.11, and 0.08 for BRWT, PW, PE, SI, and TB, respectively. Estimated breeding values were compared between lines by using a model including generation, line within generation, and replicate within line as the error term. Estimates of genetic divergence were 20.7 [+ o -] 2.7 g, 0.24 [+ or -] 0.03, 0.11 [+ or -] 0.02, and 0.07 [+ or -] 0.02 per generation for PW, PE, SI, and TB, respectively (P < 0.01), but divergence was not significant for BRWT. At Generation 4, direct EBV was higher in L than in H for PW (55.9 [+ or -] 8.7 vs. -24.2 [+ or -] 9.5 g, respectively; P < 0.01) and higher in H than in L for PE (0.58 [+ or -] 0.10 vs. -0.35 [+ or -] 0.09 g, respectively; P < 0.01). However, EBV was not different for BRWT, SI, or TB. These results indicate that PW and PE are susceptible to change by genetic selection; however, the correlated response in TB was an unexpected genetic trend toward a higher TB in L of 0.05 [+ or -] 0.01 piglets per generation (P < 0.01). Key Words: Genetic Parameters, Pigs, Placental Efficiency, Selection

The objective of this study was to evaluate correlated response in placental efficiency to selection for components of litter size. Fourteen generations of selection had resulted in a difference between lines of three fully formed piglets at birth. Gilts from a line selected for an index of components of litter size (S, n = 33) and a randomly selected control (C, n = 27) were observed at farrowing. At delivery, the umbilical cord of each piglet was double tagged with identically numbered mouse ear tags to allow the piglet's weight to be matched to the corresponding placental weight. Litter size, placental weight, birth weight, and placental vascularity were recorded. Litter size was higher (12.0 [+ or -] 0.7 vs 7.9 [+ or -] 0.7) in S than in C (P < 0.001). Line differences in placental vascularity were not significant with or without adjustment for litter size (P = 0.45 and 0.39, respectively). Correlated response to selection for components of litter size resulted in a reduced birth weight (S 82.6% of C, P < 0.001) and a reduced placental weight (S 90.9% of C, P = 0.11). After adjusting for litter size, line differences in neither placental weight nor birth weight were significant (P = 0.40 and 0.07, respectively), which indicates that the reduction in birth weight was, for the most part, due to the increase in litter size. The result of the difference in the magnitude of the change for both weights was that placental efficiency, measured as the ratio of birth weight:placental weight was 0.43 higher in C (P = 0.05). Adjustment for litter size increased the difference in placental efficiency to 0.52 (P = 0.02). Since a significant difference in litter size favoring the selected line was observed, we hypothesize that this physiological response was achieved through mechanisms other than improved placental efficiency. Key Words: Litter Size, Pigs, Placenta, Selection

Background/Aims: Visuospatial impairments are known to occur in Alzheimer's disease (AD). We hypothesised that functional magnetic resonance imaging (fMRI) response in task-related brain regions would be impaired in patients with AD during the task and that treatment with acetyl cholinesterase inhibitors would enhance activations in brain regions concerned with this visual perceptual processing. Method: Ten AD subjects were neuropsychologically assessed and underwent fMRI imaging whilst performing a series of visuospatial perception tasks, before and after treatment with acetyl cholinesterase inhibitors. Eleven healthy elderly comparison subjects were also scanned twice. Results: Regions of increased brain activation in AD included the left precuneus, left cuneus, left supramarginal gyrus, right parieto-temporal cortex and right inferior parietal lobule. Further, increased activation in the left precuneus was found to correlate significantly with improved functioning of activities of daily living. Conclusions: We believe this to be the first fMRI study that, after controlling for the confound of repeat scanning, demonstrates altered patterns of brain activation associated with visuospatial processing following treatment in patients with AD. The treatment-related improvement of visual perception in AD may rely on enhanced attentional mechanisms, thereby possibly supporting independent living through improvement on activities of daily living. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Inborn errors of metabolism (IEM) are more than 550 diseases in which there is a deficiency or absence of proteins with enzymatic, transporter, receptor or structural activity. Individually these diseases are rare, but because of their wide variety they are, considered together, the largest neonatal disease. To detect metabolites produced in IEM qualitative tests can be used. They are easily accessible and fast to carry out, and serve as presumptive elements before proceeding to more specialized tests or to focus diagnosis. Given their importance for the early diagnosis of IEM, this article aims to describe the functioning of the following biochemical tests: dinitrophenylhydrazine, resorcinol, nitrosonaphtol, nitroprusside and Hoesch, emphasizing in the metabolites that they detect.

Patients with Barrett's esophagus (BE) and low-grade dysplasia (LGD) are at increased risk of esophageal adenocarcinoma (EAC), although many regress to nondysplastic BE. This has significant clinical importance for patients being considered for endoscopic eradication therapy. Our aim is to determine the risk for progression in patients with confirmed persistent LGD. We performed a single-center retrospective cohort study of patients with BE and confirmed LGD between 2006 and 2016. Confirmed LGD was defined as LGD diagnosed by consensus conference with an expert GI pathologist or review by an expert GI pathologist and persistence as LGD present on subsequent endoscopic biopsy. The primary outcome was the incidence rate of HGD (high-grade dysplasia)/EAC. Secondary outcomes included risk factors for dysplastic progression. Risk factors for progression were assessed using univariate and multivariate analysis with logistic regression. Of 69 patients (mean age 65.2 years) with confirmed LGD were included. In total, 16 of 69 patients (23.2%) with LGD developed HGD/EAC during a median follow-up of 3.74 years (IQR, 1.24–5.45). For persistent confirmed LGD, the rate was 6.44 (95% confidence interval (CI), 2.61–13.40) compared to 2.61 cases per 100 patient-years (95% CI, 0.83–6.30) for nonpersistent LGD. Persistent LGD was found in only 29% of patients. Persistent LGD was an independent risk factor for the development of HGD/EAC (OR 4.18; [95% CI, 1.03–17.1]). Persistent confirmed LGD, present in only 1/3 of patients, was an independent risk factor for the development of HGD/EAC. Persistence LGD may be useful in decision making regarding the management of BE. [ABSTRACT FROM AUTHOR]