Congenital disorder of glycosylation type 1a: three siblings with a mild neurological phenotype.

We report 3 siblings (1 male and 2 female) recently diagnosed with congenital disorder of glycosylation type Ia (CDG-Ia) in their mid-20s. They experience mild mental retardation but manage to function independently in society. Their professions are library assistant, professional artistic painter and secretarial work. All three siblings have cerebellar hypoplasia and ataxia, but are able to ambulate easily. Two of the siblings have required strabismus surgical repairs. All have antithrombin III deficiency, osteoporosis, and mild dysmorphic features. Hypergonadotrophic hypogonadism was a feature of the two female siblings. A type 1 sialotransferrin pattern and phosphomannomutase (PMM) deficiency have been demonstrated. They are compound heterozygotes for R141H and L32R mutations in the PMM2 gene. While there is clinical heterogeneity in CDG-Ia, we believe that our patients are among the mildest of intellectually affected CDG-Ia patients reported to date.     

Arteriosclerotic changes in the myocardium, lung, and kidney in dogs with chronic congestive heart failure and myxomatous mitral valve disease.

BACKGROUND: The occurrence of small vessel arteriosclerosis in the myocardium, kidney, and lung in dogs with naturally occurring myxomatous mitral valve disease has not been previously investigated systematically. METHODS: Twenty-one dogs with naturally occurring congestive heart failure and 21 age-matched, sex-matched, and weight-matched control dogs underwent extensive pathological and histopathological examination. Morphometry and scoring of tissue sections were used to measure arterial narrowing and fibrosis in the myocardium, kidney, and lung; and intimal thickness and plaque formation in the aorta and pulmonary artery. RESULTS: Dogs with congestive heart failure had significantly more arterial narrowing in the left ventricle (P < .003), lung (P < .0001), and kidney (P < .02); intimal-medial thickening in the pulmonary artery (P = .04); and fibrosis in the left ventricle (P < .0001) than control dogs. However, they did not have more plaque formation or intimal-medial thickening in the aorta than controls. There was significantly more arterial narrowing in papillary muscles than in all other locations in dogs with congestive heart failure (P < .002). In control dogs, arterial changes were less pronounced and did not differ in different locations. CONCLUSIONS: Dogs with naturally occurring myxomatous mitral valve disease have significantly more arterial changes in the myocardium, lung, and kidney, and significantly more fibrosis in the myocardium than control dogs. This could have important implications in the management of myxomatous mitral valve disease and raises interesting questions about the occurrence and importance of intramural small vessel disease in humans with primary mitral valve prolapse.     

Concurrent performance of two working memory tasks: potential mechanisms of interference

When two tasks are performed simultaneously, performance often deteriorates, with concomitant increases in reaction time and error rate. Three potential neurophysiological mechanisms behind this deterioration in performance have been considered here: (i) dual-task performance requires additional cognitive operations and activation of cortical areas in addition to those active during single-task performance; (ii) two tasks interfere if they require activation of the same part of cortex; and (iii) cross-modal inhibition causes interference between two tasks involving stimuli from different sensory modalities. Positron emission tomography was used to measure regional cerebral blood flow (rCBF) during performance of an auditory working memory (WM) task, a visual WM task, both WM tasks (dual task) and a control condition. Compared to the control condition, the auditory and visual WM tasks activated sensory-specific areas in the superior temporal gyrus and occipital pole respectively. Both WM tasks also activated overlapping parts of cortex in the dorsolateral prefrontal, inferior parietal and cingulate cortex. There was no separate cortical area which was activated only in the dual task, and thus no area which could be associated with any dual task specific cognitive process such as task-coordination or divided attention. Decrease in rCBF in one WM task did not overlap with the areas of rCBF increase in the other WM task. However, an inhibitory mechanism could not be ruled out, since the rCBF increase in sensory specific areas was smaller in the dual- task condition than in the single-task conditions. The cortical activity underlying WM was to a large extent organized in a non-sensory specific, or non-parallel, way, and the results are consistent with the hypothesis that concurrent tasks interfere with each other if they demand activation of the same part of cortex.      

Impaired tactile pattern recognition in the early stage of primary degenerative dementia compared with normal aging

Tactile pattern recognition of ten different patterns which were engraved upon 4 x 4 cm plastic plaquettes with one hand and thereafter drawing with the other or the same hand was tested in 21 patients with a mild stage primary degenerative presenile onset dementia of Alzheimer type (DAT) and in 14 patients with a questionable dementia on the background of a chronic cardiovascular disease (CVD) in comparison to 15 healthy subjects of the same age (51 years old, elder controls, (EC)) and 16 younger subjects (22 years old, younger controls, (YC)). Patients made about four times more errors than the EC group. Duration from the begin of touching to the end of drawing was significantly longer in patients than in controls. In a second task the subjects had to recognize four subsequent patterns, then to perform a standard multiplication task and afterwards to draw all four patterns in their correct sequence. Patients made about ten times more errors in pattern recognition and series reproduction than age-matched controls.     

Immune Responses to Bile-Tolerant Helicobacter Species in Patients with Chronic Liver Diseases, a Randomized Population Group, and Healthy Blood Donors

Bile-tolerant Helicobacter species such as Helicobacter pullorum, Helicobacter bilis, and Helicobacter hepaticus are associated with hepatic disorders in animals and may be involved in the pathogenesis of chronic liver diseases (CLD) in humans. Antibody responses to cell surface proteins of H. pullorum, H. bilis, and H. hepaticus in serum samples from patients with CLD, a randomized population group, and healthy blood donors were evaluated by using enzyme linked immunosorbent assay (ELISA). The results were compared with the antibody responses to Helicobacter pylori. For analysis of a possible cross-reactivity between bile-tolerant Helicobacter species and H. pylori, sera from a subpopulation of each group were absorbed with a whole-cell extract of H. pylori and retested by ELISA. Results before absorption showed that the mean value of the ELISA units for H. pullorum was significantly higher in patients with CLD than in healthy blood donors (P = 0.01). Antibody reactivity to cell surface protein of H. hepaticus was also significantly higher in the CLD patients than in the healthy blood donors and the population group (P = 0.005 and P = 0.002, respectively). Following the absorption, antibody responses to H. pullorum decreased significantly in all three groups (P = 0.0001 for CLD patients, P = 0.0005 for the population group, and P < 0.0001 for the blood donors), indicating that cross-reactivity between H. pylori and other Helicobacter spp. occurs. The antibody responses to H. hepaticus and H. bilis in CLD patients remained high following absorption experiments compared to ELISA results before absorption. The significance of this finding requires further investigations.     

SpecialEscherichia coli serotypes among enterotoxigenic strains from diarrhoea in adults and children

106 enterotoxigenicEscherichia coli strains from children and adults from many parts of the world were serotyped for O and H antigens. Some OH types,i.e. O6H16, O8H9, O15H11, O25H42, O78H11 and O78H12, were found repeatedly from different geographical locations. Some of these OH serotypes were only found rarely among more than 20000E. coli strains collected over many years from different locations and sources. It is suggested that these special OH serotypes represent clones which have been selected to the special conditions in the small intestine and selected to carry the plasmids necessary to provoke diarrhoea.     

Working memory brain activity and capacity link MAOA polymorphism to aggressive behavior during development

A developmental increase in working memory capacity is an important part of cognitive development, and low working memory (WM) capacity is a risk factor for developing psychopathology. Brain activity represents a promising endophenotype for linking genes to behavior and for improving our understanding of the neurobiology of WM development. We investigated gene–brain–behavior relationships by focusing on 18 single-nucleotide polymorphisms (SNPs) located in six dopaminergic candidate genes (COMT, SLC6A3/DAT1, DBH, DRD4, DRD5, MAOA). Visuospatial WM (VSWM) brain activity, measured with functional magnetic resonance imaging, and VSWM capacity were assessed in a longitudinal study of typically developing children and adolescents. Behavioral problems were evaluated using the Child Behavior Checklist (CBCL). One SNP (rs6609257), located ∼6.6 kb downstream of the monoamine oxidase A gene (MAOA) on human chromosome X, significantly affected brain activity in a network of frontal, parietal and occipital regions. Increased activity in this network, but not in caudate nucleus or anterior prefrontal regions, was correlated with VSWM capacity, which in turn predicted externalizing (aggressive/oppositional) symptoms, with higher WM capacity associated with fewer externalizing symptoms. There were no direct significant correlations between rs6609257 and behavioral symptoms. These results suggest a mediating role of WM brain activity and capacity in linking the MAOA gene to aggressive behavior during development.