Neurocognitive Function in Acromegaly after Surgical Resection of GH-Secreting Adenoma versus Na?ve Acromegaly

Patients with active untreated acromegaly show mild to moderate neurocognitive disorders that are associated to chronic exposure to growth hormone (GH) and insulin-like growth factor (IGF-I) hypersecretion. However, it is unknown whether these disorders improve after controlling GH/IGF-I hypersecretion. The aim of this study was to compare neurocognitive functions of patients who successfully underwent GH-secreting adenoma transsphenoidal surgery (cured patients) with patients with naive acromegaly. In addition, we wanted to determine the impact of different clinical and biochemical variables on neurocognitive status in patients with active disease and after long-term cure. A battery of six standardized neuropsychological tests assessed attention, memory and executive functioning. In addition, a quantitative electroencephalography with Low-Resolution Electromagnetic Tomography (LORETA) solution was performed to obtain information about the neurophysiological state of the patients. Neurocognitive data was compared to that of a healthy control group. Multiple linear regression analysis was also conducted using clinical and hormonal parameters to obtain a set of independent predictors of neurocognitive state before and after cure. Both groups of patients scored significantly poorer than the healthy controls on memory tests, especially those assessing visual and verbal recall. Patients with cured acromegaly did not obtain better cognitive measures than naïve patients. Furthermore memory deficits were associated with decreased beta activity in left medial temporal cortex in both groups of patients. Regression analysis showed longer duration of untreated acromegaly was associated with more severe neurocognitive complications, regardless of the diagnostic group, whereas GH levels at the time of assessment was related to neurocognitive outcome only in naïve patients. Longer duration of post-operative biochemical remission of acromegaly was associated with better neurocognitive state. Overall, this data suggests that the effects of chronic exposure to GH/IGF-I hypersecretion could have long-term effects on brain functions.     

Elimination of Von Hippel-Lindau Function Perturbs Pancreas Endocrine Homeostasis in Mice

Mutations in the human homolog of the Vhlh gene [encoding the von-Hippel Lindau (VHL) protein] lead to tumor development. In mice, depletion of Vhlh in pancreatic ß-cells causes perturbed glucose homeostasis, but the role of this gene in other pancreatic cells is poorly understood. To investigate the function of VHL/HIF pathway in pancreatic cells, we inactivated Vhlh in the pancreatic epithelium as well as in the endocrine and exocrine lineages. Our results show that embryonic depletion of Vhlh within the pancreatic epithelium causes postnatal lethality due to severe hypoglycemia. The hypoglycemia is recapitulated in mice with endocrine-specific removal of Vhlh, while animals with loss of Vhlh predominantly in the exocrine compartment survive to adulthood with no overt defects in glucose metabolism. Mice with hypoglycemia display diminished insulin release in response to elevated glucose. Significantly, the glucagon response is impaired both in vivo (circulating glucagon levels) as well as in an in vitro secretion assay in isolated islets. Hypoxia also impairs glucagon secretion in a glucagon-expressing cell line in culture. Our results reveal a novel role for the hypoxia/HIF pathway in islet hormone secretion and maintenance of the fine balance that allows for the establishment of normoglycemia.     

Paleomicrobiology: Revealing Fecal Microbiomes of Ancient Indigenous Cultures

Coprolites are fossilized feces that can be used to provide information on the composition of the intestinal microbiota and, as we show, possibly on diet. We analyzed human coprolites from the Huecoid and Saladoid cultures from a settlement on Vieques Island, Puerto Rico. While more is known about the Saladoid culture, it is believed that both societies co-existed on this island approximately from 5 to 1170 AD. By extracting DNA from the coprolites, followed by metagenomic characterization, we show that both cultures can be distinguished from each other on the basis of their bacterial and fungal gut microbiomes. In addition, we show that parasite loads were heavy and also culturally distinct. Huecoid coprolites were characterized by maize and Basidiomycetes sequences, suggesting that these were important components of their diet. Saladoid coprolite samples harbored sequences associated with fish parasites, suggesting that raw fish was a substantial component of their diet. The present study shows that ancient DNA is not entirely degraded in humid, tropical environments, and that dietary and/or host genetic differences in ancient populations may be reflected in the composition of their gut microbiome. This further supports the hypothesis that the two ancient cultures studied were distinct, and that they retained distinct technological/cultural differences during an extended period of close proximity and peaceful co-existence. The two populations seemed to form the later-day Taínos, the Amerindians present at the point of Columbian contact. Importantly, our data suggest that paleomicrobiomics can be a powerful tool to assess cultural differences between ancient populations.     

Long-term effects of postovulatory aging of mouse oocytes on offspring: a two-generational study.

Aims of this study were to analyze the long-term effects of postovulatory aging of mouse oocytes on 1) reproductive traits of parental (F(0)) and first (F(1))-generation females (pregnancy rate, gestation length, litter size, perinatal death, and sex ratio of offspring) and 2) developmental and behavioral variables of F(1) and second-generation (F(2)) offspring (birth weight and weight gain during preweaning development, postnatal day of attainment of immediate righting, spontaneous motor activity, and passive and active conditioned learning ability). Hybrid (C57BL/6JIco x CBA/JIco) females were artificially inseminated at 13 h (control group) or 22 h (oocyte-aged group) after GnRH injection. Experimental (oocyte-aged group) F(0) females exhibited lower pregnancy rate, shortened gestation length, decreased litter size, higher perinatal death of their pups, and increased percentage of male offspring compared to control F(0) females. Postovulatory aging of oocytes was also associated with increased number of growth-retarded pups, delayed development of the righting reflex, and higher spontaneous motor activity and emotionality of F(1) offspring. Postovulatory aging of F(0) oocytes did not affect birth weight, weight gain during preweaning development, passive and active conditioned learning ability of F(1) offspring, or reproductive traits of F(1) females or developmental and behavior variables of F(2) offspring.     

Use of the EM algorithm to detect QTL affecting multiple-traits in an across half-sib family analysis

QTL detection experiments in livestock species commonly use the half-sib design. Each male is mated to a number of females, each female producing a limited number of progeny. Analysis consists of attempting to detect associations between phenotype and genotype measured on the progeny. When family sizes are limiting experimenters may wish to incorporate as much information as possible into a single analysis. However, combining information across sires is problematic because of incomplete linkage disequilibrium between the markers and the QTL in the population. This study describes formulæ for obtaining MLEs via the expectation maximization (EM) algorithm for use in a multiple-trait, multiple-family analysis. A model specifying a QTL with only two alleles, and a common within sire error variance is assumed. Compared to single-family analyses, power can be improved up to fourfold with multi-family analyses. The accuracy and precision of QTL location estimates are also substantially improved. With small family sizes, the multi-family, multi-trait analyses reduce substantially, but not totally remove, biases in QTL effect estimates. In situations where multiple QTL alleles are segregating the multi-family analysis will average out the effects of the different QTL alleles.     

Influence of sex, slaughter weight and carcass weight on “non-carcass” and carcass quality in segureña lambs

The effects of sex, slaughter weight and carcass weight on carcass characteristics and meat quality traits were evaluated using 100 Segureña lambs. The management of all lambs was similar prior to slaughter at 19–25 kg. Slaughtered animals with a hot carcass weight below 20 kg were assigned to class B, and those greater than 22 kg to class C. Carcass weight had a significant influence on “non-carcass” components, dressing percentage, subjective carcass conformation, fat deposits, carcass fatness, bone and most carcass measurements. Sex had a significant effect on age at slaughter, “non-carcass” components, rib measurements, dressing percentage, fat deposits, and neck and shoulder percentage. As the weight increased, the carcass measurements also increased. Concurrently, while improving the conformation indices of the carcass, leg and dressing percentages, neither the commercial cuts of the animal nor tissue composition was significantly affected. Sex primarily affected the quantity of all types of fat deposits.     

Sensitive fluorescence in situ hybridization signal detection in maize using directly labeled probes produced by high concentration DNA polymerase nick translation

The signal produced by fluorescence in situ hybridization (FISH) often is inconsistent among cells and sensitivity is low. Small DNA targets on the chromatin are difficult to detect. We report here an improved nick translation procedure for Texas red and Alexa Fluor 488 direct labeling of FISH probes. Brighter probes can be obtained by adding excess DNA polymerase I. Using such probes, a 30 kb yeast transgene, and the rp1, rp3 and zein multigene clusters were clearly detected.