2,614 research outputs found
Both selective and neutral processes drive GC content evolution in the human genome
Mammalian genomes consist of regions differing in GC content, referred to as isochores or GC-content domains. The scientific debate is still open as to whether such compositional heterogeneity is a selected or neutral trait. RESULTS: Here we analyze SNP allele frequencies, retrotransposon insertion polymorphisms (RIPs), as well as fixed substitutions accumulated in the human lineage since its divergence from chimpanzee to indicate that biased gene conversion (BGC) has been playing a role in within-genome GC content variation. Yet, a distinct contribution to GC content evolution is accounted for by a selective process. Accordingly, we searched for independent evidences that GC content distribution does not conform to neutral expectations. Indeed, after correcting for possible biases, we show that intron GC content and size display isochore-specific correlations. CONCLUSION: We consider that the more parsimonious explanation for our results is that GC content is subjected to the action of both weak selection and BGC in the human genome with features such as nucleosome positioning or chromatin conformation possibly representing the final target of selective processes. This view might reconcile previous contrasting findings and add some theoretical background to recent evidences suggesting that GC content domains display different behaviors with respect to highly regulated biological processes such as developmentally-stage related gene expression and programmed replication timing during neural stem cell differentiation
GC-FID data of biocatalytic esterification reactions & NMR data of lignin characterization
Tabulated chromatographic data (GC-FID) from butyl butyrate esterification reactions. 13C and 31P NMR data from pine kraft lignin (BIOPIVA 100) and cationic pine kraft lignin. A list of sample code identifiers with their descriptions is available upon request from the author.<br
A double blind, placebo-controlled, phase II, add-on study of cyclophosphamide (CTX) for 24 months in patients affected by multiple sclerosis on a background therapy with interferon-beta study denomination: CYCLIN
Gray Matter Atrophy and Microstructural White Matter Abnormalities Underlying Cognitive Impairment in Benign MS
Abnormal adaptation over timeof motornetwork recruitment in multiple sclerosis patients with fatigue
Objectives: Using functional magnetic resonance imaging (fMRI) during a motor task, we investigated the functional correlates of central fatigue in multiple sclerosis (MS), and adaptation of motor network recruitment during a prolonged effort. Methods: Motor fMRI was obtained from 79 MS patients (50 fatigued (F), 29 non-fatigued (nF)) and 26 matched healthy controls (HC). Cognitive and physical fatigue were rated using the Modified Fatigue Impact Scale (MFIS). Results: Compared to HC and nF patients, F-MS patients experienced reduced activations of the left middle temporal gyrus, left supplementary motor area (SMA), bilateral superior frontal gyrus, left postcentral gyrus and basal ganglia regions. They also showed increased activation of the right middle frontal gyrus (MFG). Time-modulation analysis showed a reduced activity of the SMA and right precentral gyrus, and increased activity of the basal ganglia in HC. Such a trend was impaired in F-MS patients. In MS patients, increased MFG activity was related to MFIS scores. Physical MFIS score was related to a reduced recruitment of the right thalamus and SMA. Conclusions: Abnormalities and impaired timing of activation between different areas of the motor and executive networks occur in F-MS patients. The dysfunction of critical cortical areas contributes to the occurrence of central fatigue
Autoantibodies to glutamic acid decarboxylase in a patient with stiff-man syndrome, epilepsy, and type I diabetes mellitus
Stiff-man syndrome is a rare disorder of the central nervous system consisting of progressive, fluctuating muscle rigidity with painful spasms. It is occasionally associated with endocrine disorders, including insulin-dependent diabetes, and with epilepsy. We investigated the possible existence of autoimmunity against the nervous system in a patient with stiff-man syndrome associated with epilepsy and Type I diabetes mellitus. Levels of IgG, which had an oligoclonal pattern, were elevated in the cerebrospinal fluid. The serum and the cerebrospinal fluid produced an identical, intense staining of all gray-matter regions when used to stain brain sections according to an indirect light-microscopical immunocytochemical procedure. The staining patterns were identical to those produced by antibodies to glutamic acid decarboxylase (the enzyme responsible for the synthesis of gamma-aminobutyric acid). A band comigrating with glutamic acid decarboxylase in sodium dodecyl sulfate-polyacrylamide gels appeared to be the only nervous-tissue antigen recognized by cerebrospinal fluid antibodies, and the predominant antigen recognized by serum antibodies. These findings support the idea that an impairment of neuronal pathways that operate through gamma-aminobutyric acid is involved in the pathogenesis of stiff-man syndrome, and they raise the possibility of an autoimmune pathogenesis
Meetresultaten Kunststof GC-elementen: Project C2: Oever- en Bodembescherming met GC
Anome BV en het Innovatie Test Centrum van Rijkswaterstaat-DWW zijn samen met verschillende partners aan het onderzoeken in hoeverre Ground Consolidators (GC\u92s) interessant zouden kunnen zijn voor gebruik in Oever- en bodembescherming. De eerste fase van het onderzoek is afgerond en er is besloten om verdergaand onderzoek te doen. In verband met duurzaamheid van het materiaal, is ervoor gekozen om verder onderzoek te verrichten naar GC-elementen van kunststof. Dit onderzoek is gedaan door een drietal studenten van de TU Delft aan de faculteit Civiele Techniek. Voorliggend document bevat de meetresultaten van de kwali- en kwantitatieve experimenten die zijn uitgevoerd om de eigenschappen van kunststoffen GC\u92s en een pakket GC\u92s te bepalen
Meetresultaten Kunststof GC-elementen: Versie 4
Anome BV en het Innovatie Test Centrum van Rijkswaterstaat-DWW zijn samen met verschillende partners aan het onderzoeken in hoeverre Ground Consilidators (GC\u92s) interessant zouden kunnen zijn voor gebruik in Oever- en bodembescherming. De eerste fase van het onderzoek is afgerond en er is besloten om verdergaand onderzoek te doen. In verband met duurzaamheid van het materiaal, is ervoor gekozen om verder onderzoek te verrichten naar GC-elementen van kunststof. Dit onderzoek is gedaan door een drietal studenten van de TU Delft aan de faculteit Civiele Techniek. Voorliggend document bevat de meetresultaten van de kwali- en kwantitatieve experimenten die zijn uitgevoerd om de eigenschappen van kunststoffen GC\u92s en een pakket GC\u92s te bepalen
The Private Cost of Long-Term Care in Canada: Where You Live Matters
Canadians expect the same access to health care whether they are rich or poor, and wherever they live, often without direct charge at the point of service. However, we find that the private cost of long-term care differs greatly across the country, and within provinces, we find substantial variation, depending on income level, marital status, and, in Quebec alone, on assets owned. A non-married person with average income would pay more than twice as much in the Atlantic provinces as in Quebec, while a couple with one in care would pay almost four times as much in Newfoundland as in Alberta.long-term care, private cost
Meetresultaten \u93extra proef\u94 Kunststof GC-elementen: Stabiliteit, soortelijk gewicht en elasticiteit
Dit rapport is een aanvulling op het eindverslag van het onderzoek naar het gedrag van kunststof GC elementen voor oever- en bodembescherming. Conclusies van dat (schaal-) onderzoek waren dat een structuur van GC elementen verrassend sterke hydraulische eigenschappen bezit en daarmee interessant is als erosiebeschermer bij bodem en oeverconstructies. Beperking in het gebruik lag bij \u93stabiliteit\u94. Onder sterke stroming of golfslag was het pakket onvoldoende stabiel. Zo werden er onder zeer sterke stroming flarden uit getrokken, of bewoog het pakket enigszins onder golfslag op een talud. Er werden verschillende kunststoffen gebruikt, met verschillende soortelijke gewichten. Uit extrapolatie en precieze bestudering van het bezwijken kon verwacht worden dat gebruik van sterkere GC\u92s (minder elastisch) en zwaardere GC\u92s (stabieler) het bereik waarin de GC gebruikt kan worden aanzienlijk zou moeten kunnen vergroten
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