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21.
Processing speed is a psychological construct that refers to the speed with which an individual can perform any cognitive operation. Processing speed correlates strongly with general cognitive ability, declines sharply with age and is impaired across a number of neurological and psychiatric disorders. Thus, identifying genes that influence processing speed will likely improve understanding of the genetics of intelligence, biological aging and the etiologies of numerous disorders. Previous genetics studies of processing speed have relied on simple phenotypes (eg, mean reaction time) derived from single tasks. This strategy assumes, erroneously, that processing speed is a unitary construct. In the present study, we aimed to characterize the genetic architecture of processing speed by using a multidimensional model applied to a battery of cognitive tasks. Linkage and QTL‐specific association analyses were performed on the factors from this model. The randomly ascertained sample comprised 1291 Mexican‐American individuals from extended pedigrees. We found that performance on all three distinct processing‐speed factors (Psychomotor Speed; Sequencing and Shifting and Verbal Fluency) were moderately and significantly heritable. We identified a genome‐wide significant quantitative trait locus (QTL) on chromosome 3q23 for Psychomotor Speed (LOD = 4.83). Within this locus, we identified a plausible and interesting candidate gene for Psychomotor Speed (Z = 2.90, P = 1.86 × 10?03).  相似文献   
22.
Potent estrogen receptor ligands typically contain a phenolic hydrogen-bond donor. The indazole of the selective estrogen receptor degrader (SERD) ARN-810 is believed to mimic this. Disclosed herein is the discovery of ARN-810 analogs which lack this hydrogen-bond donor. These SERDs induced tumor regression in a tamoxifen-resistant breast cancer xenograft, demonstrating that the indazole NH is not necessary for robust ER-modulation and anti-tumor activity.  相似文献   
23.
Hydrophobic interaction chromatography is a very popular chromatography method for purification of proteins and plasmids in all scales from analytical to industrial manufacturing. Despite this frequent use, the complex interaction mechanism and the thermodynamic aspects of adsorption in hydrophobic interaction chromatography are still not well understood. Calorimetric methods such as isothermal titration calorimetry and flow calorimetry can help to gain a deeper understanding of the adsorption strength, the influence of salt type and temperature. They can be used to study conformational changes of proteins, which are often associated with the adsorption in hydrophobic interaction chromatography. This review offers a detailed introduction into the thermodynamic fundamentals of adsorption in hydrophobic interaction chromatography with a special focus on the potential applications of isothermal titration calorimetry and flow calorimetry for studying specific problems and relationships of the adsorption behavior of proteins and its various influencing factors. Models for characterizing conformational changes upon adsorption are presented together with methods for assessing this problem for different proteins and stationary phases. All of this knowledge can contribute greatly to forming a sound basis for method development, process optimization and finding modelling strategies in hydrophobic interaction chromatography.  相似文献   
24.
Mitochondria are crucial for numerous cellular processes, yet the regulation of mitochondrial functions is only understood in part. Recent studies indicated that the number of mitochondrial phosphoproteins is higher than expected; however, the effect of reversible phosphorylation on mitochondrial structure and function has only been defined in a few cases. It is thus crucial to determine authentic protein phosphorylation sites from highly purified mitochondria in a genetically tractable organism. The yeast Saccharomyces cerevisiae is a major model organism for the analysis of mitochondrial functions. We isolated highly pure yeast mitochondria and performed a systematic analysis of phosphorylation sites by a combination of different enrichment strategies and mass spectrometry. We identified 80 phosphorylation sites in 48 different proteins. These mitochondrial phosphoproteins are involved in critical mitochondrial functions, including energy metabolism, protein biogenesis, fatty acid metabolism, metabolite transport, and redox regulation. By combining yeast genetics and in vitro biochemical analysis, we found that phosphorylation of a serine residue in subunit g (Atp20) regulates dimerization of the mitochondrial ATP synthase. The authentic phosphoproteome of yeast mitochondria will represent a rich source to uncover novel roles of reversible protein phosphorylation.  相似文献   
25.
26.
The hyporheic zone and its interactions with coarse surface sediments is increasingly reported by aquatic ecologists because the water exchanges between surface and subsurface are important factors for the understanding of the ecosystem functioning. However, the hyproheic oligochaete assemblages have received less attention than other assemblages such as crustaceans. In addition, studies investigating the incidence of pollution in watercourses have mostly focused on the benthic zone and have neglected the hyporheic zone. Some examples are given from an unpolluted glacial river (Roseg), polluted plains rivers (Moselle, Rhône) and a protected wetland in an urbanized environment. The hyporheic zone kept the memory of past and present incidences of pollution, in particular when downwellings of polluted surface waters to the hyporheic zone predominated. The Active hydrologic Exchange Describers between surface and subsurface (AED oligochaete species) were the same in the glacial river Roseg, the rivers Rhône and Moselle and the urbanized wetland. The predominance of pollution-tolerant species like Limnodrilus hoffmeisteri was observed in polluted groundwater as well as in polluted surface coarse sediments. Moreover, the urbanized wetland exhibited a high species richness, suggesting that the hyporheic zone is a reservoir of species. The oligochaete communities enable biologists to simultaneously assess the pollution incidence, the permeability of coarse habitats, the water exchanges between surface and subsurface, and give an approximate measure of the metabolic activities in the sediments. Consequently, the simultaneous study of surface and hyporheic oligochaete assemblages is of great interest when considering the ecological functioning of watercourses and the incidence of pollution inputs.  相似文献   
27.
Lebanon is an eastern Mediterranean country inhabited by approximately four million people with a wide variety of ethnicities and religions, including Muslim, Christian, and Druze. In the present study, 926 Lebanese men were typed with Y-chromosomal SNP and STR markers, and unusually, male genetic variation within Lebanon was found to be more strongly structured by religious affiliation than by geography. We therefore tested the hypothesis that migrations within historical times could have contributed to this situation. Y-haplogroup J*(xJ2) was more frequent in the putative Muslim source region (the Arabian Peninsula) than in Lebanon, and it was also more frequent in Lebanese Muslims than in Lebanese non-Muslims. Conversely, haplogroup R1b was more frequent in the putative Christian source region (western Europe) than in Lebanon and was also more frequent in Lebanese Christians than in Lebanese non-Christians. The most common R1b STR-haplotype in Lebanese Christians was otherwise highly specific for western Europe and was unlikely to have reached its current frequency in Lebanese Christians without admixture. We therefore suggest that the Islamic expansion from the Arabian Peninsula beginning in the seventh century CE introduced lineages typical of this area into those who subsequently became Lebanese Muslims, whereas the Crusader activity in the 11(th)-13(th) centuries CE introduced western European lineages into Lebanese Christians.  相似文献   
28.
Lily-Arison, R.de R. 2000. Breeding biology of Frances's Sparrowhawk Accipiter francesii in a lowland rainforest of northeastem Madagascar. Ostrich 71 (1 & 2): 332–335.

Frances's Sparrowhawks Accipiter fmncesii were studied during the breeding seasons 1994 and 1995 on Masoala Peninsula of northeastern Madagascar. Breeding coincides with the dry season, nest building in October, egg laying in November, hatching in December and fledging in January (beginning of the wet season). All but one of 10 pairs built new nests in 1995 and the mean distance of nest site from 1994 and 1995 nests was 105± 100 m (n = 6, ranging from 0 to 250m). Nests in primary forest were incubated for 79% of the observation time by females, 3% by males and eggs were unattended for 18% of the observation time. On a numerical basis the diet was composed of lizards (56%) and birds (23%), making up more than 79% of the identified prey items. A total of 33 eggs was laid in 13 nests (average clutch size 2.5). In 13 breeding attempts 29 (88%) hatched and all of those hatchlings fledged. Of the 14 My-documented breeding attempts 2.1 young fledged per breeding attempt and overall nesting success was 93%.

L'Épervier de France Accipiter francesii a été étudié pendant la saison de reproduction en 1994 et 1995 dans la Presqu'Ile Masoala, au partie Nord-Est de Madagascar. La saison de reproduction de cette espkce coincide avec la saison sèche: la construction du nid en Octobre, la ponte en Novembre, I'élosion en Déembre et l'envol du poussin en Janvier (début de la saison pluviale). Tous, sauf une des 10 paires ont construit des nouveaw nids en 1995 et la distance moyenne de I'endroit du nid de I'anné 1994 et 1995 est de 105 + 100 m (n = 6, variant de 0 à 250m). Dans la for[ebar]t primaire, les oeufs ont éeté incubés par la femelle pendant 79% du temps d'observation, 3% par le mile et non incubés pendant 18% du temps. Les proies sont principalement composées de lkzards (56%) et oiseaux (23%), atteignant plus de 79% des proies identifiés. 33 oeufs ont été pondus dans 13 nids (en moyenne 2.5 oeufs par nid). Pour ces 13 nids, 29 oeufs (88%) ont été éclos et tous ces poussins (100%) sont capables de voler. Sur 14 nids observés, 2.1 poussins par nid s'envolent et le tam de succés est de 93%.  相似文献   
29.

Background

HIV-associated tuberculosis is a common coinfection in Sub-Saharan Africa, which causes high morbidity and mortality. A sub-set of HIV-associated tuberculosis patients require prolonged hospital admission, during which antiretroviral therapy initiation may be required. The aim of this study was to document the causes of clinical deterioration of hospitalised patients with HIV-associated tuberculosis starting antiretroviral therapy in order to inform healthcare practice in low- to middle-income countries.

Methods

Prospective, observational cohort study of adult inpatients with HIV-associated tuberculosis starting antiretroviral therapy in a dedicated tuberculosis hospital in Cape Town, South Africa. Causes of clinical deterioration and outcome were recorded in the first 12 weeks of antiretroviral therapy. Patients with rifampicin-resistant tuberculosis were excluded.

Results

Between May 2009 and November 2010, 112 patients (60% female), with a median age of 32 years were enrolled. At baseline the median CD4 count was 55 cells/mm3 (IQR 31–106) and HIV viral load 5.6 log copies/mL. All patients had significant comorbidity: 82% were bed-bound, 65% had disseminated tuberculosis and 27% had central nervous system tuberculosis. Seventy six patients (68%) developed 144 clinical events after starting antiretroviral therapy. TB-IRIS, hospital-acquired infections and significant drug toxicities occurred in 42%, 20.5% and 15% of patients respectively. A new opportunistic disease occurred in 15% of patients and a thromboembolic event in 8%. Mortality during the 12 week period was 10.6%.

Conclusions

High rates of TB-IRIS, hospital-acquired infections and drug toxicities complicate the course of patients with HIV-associated tuberculosis starting antiretroviral therapy in hospital. Despite the high morbidity, mortality was relatively low. Careful clinical management and adequate resources are needed in hospitalised HIV-TB patients in the 1st three months following ART initiation.  相似文献   
30.
The investigations previously carried out by Grataroli and colleagues (1) to elucidate the relationships between dietary fatty acids, lipid composition, prostaglandin E2 production and phospholipase A2 activity in the rat gastric mucosa are, here, extended. In the present investigations, fatty acid and prostaglandin E2 catabolizing enzymes were assayed in gastric mucosa from rats fed either a low fat diet (corn oil: 4.4% w/w) (referred as control group), a corn oil-enriched diet (17%) or a salmon oil-enriched diet (12.5%) supplemented with corn oil (4.5%) (referred as groups of treated animals) for eight weeks.Peroxisomal fatty acyl-CoA β-oxidation was induced in the treated animals whereas the activities of catalase and mitochondrial tyramine oxidase were increased and normal, respectively. Mitochondrial acyl-CoA dehydrogenations occured at higher rates and carnitine acyltransferase activities were enhanced. In addition, the induction of peroxisomal but not mitochondrial prostaglandoyl-E2-CoA β-oxidation could be demonstrated. Induction of peroxisomal oxidation of fatty acids and prostaglandins is suggested to contribute to the decrease of prostaglandin E2 production in the treated animals, especially those receiving the salmon oil diet, that the above mentioned authors originally reported.  相似文献   
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