Þróun vitrænnar getu hjá börnum Alzheimers-sjúklinga

Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/OpenRannsóknir á einstaklingum með ættarsögu um Alzheimers-sjúkdóm hafa sýnt fram á aukna áhættu á að þeir þrói með sér heilabilunarsjúkdóm. Ennfremur hefur verið sýnt fram á að undirliggjandi vitræn skerðing sé greinanleg með taugasálfræðilegum prófum nokkru áður en klínísk einkenni koma fram. Rannsóknir á börnum Alzheimers-sjúklinga eru af skornum skammti. Markmið rannsóknarinnar var að skoða þróun vitrænnar getu hjá miðaldra börnum Alzheimerssjúklinga, yfir 7 ára tímabil. Þátttakendur voru valdir af handahófi úr íslenskri erfðarannsókn sem verið hefur í gangi frá árinu 1998. Þátttakendur voru 83 börn Alzheimerssjúklinga á aldrinum 47-73 ára og 30 einstaklingar í viðmiðunarhópi á aldrinum 48- 73 ára sem höfðu enga ættarsögu um heilabilunarsjúkdóm. Vitræn geta var metin tvisvar yfir 7 ára tímabil með taugasálfræðilegum prófum sem mæla áttun, yrt og óyrt minni, mál, einbeitingu, hugrænan hraða og sjónrænan hraða og úrvinnslu. Þátttakendur með þekktan mið- eða úttauga sjúkdóm voru útilokaðir frá rannsókninni. Niðurstöður gáfu ekki til kynna mun á frammistöðu hópanna tveggja á taugasálfræðilegu prófunum yfir 7 ára tímabil. Þessar niðurstöður gefa til kynna að undirliggjandi vitræn skerðing hefjist eftir 60 ára aldur hjá börnum Alzheimers-sjúklinga, ólíkt niðurstöðum margra annarra rannsókna

Ground-Based Measurements of the 2014–2015 Holuhraun Volcanic Cloud (Iceland)

The 2014–2015 Bárðarbunga fissure eruption at Holuhraun in central Iceland was distinguished by the high emission of gases, in total 9.6 Mt SO2, with almost no tephra. This work collates all ground-based measurements of this extraordinary eruption cloud made under particularly challenging conditions: remote location, optically dense cloud with high SO2 column amounts, low UV intensity, frequent clouds and precipitation, an extensive and hot lava field, developing ramparts, and high-latitude winter conditions. Semi-continuous measurements of SO2 flux with three scanning DOAS instruments were augmented by car traverses along the ring-road and along the lava. The ratios of other gases/SO2 were measured by OP-FTIR, MultiGAS, and filter packs. Ratios SO2/HCl = 30–110 and SO2/HF = 30–130 show a halogen-poor eruption cloud. Scientists on-site reported extremely minor tephra production during the eruption. OPC and filter packs showed low particle concentrations similar to non-eruption cloud conditions. Three weather radars detected a droplet-rich eruption cloud. Top of eruption cloud heights of 0.3–5.5 km agl were measured with ground- and aircraft-based visual observations, web camera and NicAIR II infrared images, triangulation of scanning DOAS instruments, and the location of SO2 peaks measured by DOAS traverses. Cloud height and emission rate measurements were critical for initializing gas dispersal simulations for hazard forecasting

Þróun vitrænnar getu hjá börnum Alzheimers-sjúklinga

Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/OpenRannsóknir á einstaklingum með ættarsögu um Alzheimers-sjúkdóm hafa sýnt fram á aukna áhættu á að þeir þrói með sér heilabilunarsjúkdóm. Ennfremur hefur verið sýnt fram á að undirliggjandi vitræn skerðing sé greinanleg með taugasálfræðilegum prófum nokkru áður en klínísk einkenni koma fram. Rannsóknir á börnum Alzheimers-sjúklinga eru af skornum skammti. Markmið rannsóknarinnar var að skoða þróun vitrænnar getu hjá miðaldra börnum Alzheimerssjúklinga, yfir 7 ára tímabil. Þátttakendur voru valdir af handahófi úr íslenskri erfðarannsókn sem verið hefur í gangi frá árinu 1998. Þátttakendur voru 83 börn Alzheimerssjúklinga á aldrinum 47-73 ára og 30 einstaklingar í viðmiðunarhópi á aldrinum 48- 73 ára sem höfðu enga ættarsögu um heilabilunarsjúkdóm. Vitræn geta var metin tvisvar yfir 7 ára tímabil með taugasálfræðilegum prófum sem mæla áttun, yrt og óyrt minni, mál, einbeitingu, hugrænan hraða og sjónrænan hraða og úrvinnslu. Þátttakendur með þekktan mið- eða úttauga sjúkdóm voru útilokaðir frá rannsókninni. Niðurstöður gáfu ekki til kynna mun á frammistöðu hópanna tveggja á taugasálfræðilegu prófunum yfir 7 ára tímabil. Þessar niðurstöður gefa til kynna að undirliggjandi vitræn skerðing hefjist eftir 60 ára aldur hjá börnum Alzheimers-sjúklinga, ólíkt niðurstöðum margra annarra rannsókna

Tumour biological features of BRCA1-induced breast and ovarian cancer

BRCA1 mutations, although implicated in disease predisposition in a major part of the hereditary breast cancer population, do not seem to be crucially involved in tumorigenesis of sporadic breast and ovarian cancers. This suggests that tumours arising in BRCA1 mutation carriers may differ from BRCA1 negative hereditary and sporadic cancer in genetic and biological features, as well as in clinical behaviour. Prior to BRCA1 analysis, 79 breast and 19 ovarian tumours from 57 breast and breast-ovarian cancer families, and 170 tumours from a comparison group of stage II breast cancers were studied with regard to histopathological features; immunohistochemistry [c-erbB-2, p53, oestrogen receptor (ER) and progesterone receptor (PR)], DNA flow cytometry and S-phase fraction. BRCA1 mutations were found in 40 breast and 15 ovarian tumours. The BRCA1 positive breast tumours were significantly more often of ductal type, histological grade III and manifested a heavy lymphocyte infiltration. Additionally, as compared to BRCA1 negative tumours, the BRCA1 positive tumours were significantly more often ER, PgR and c-erbB-2 negative. Furthermore, they were significantly more often DNA non-diploid, as well as being characterised by higher S-phase fraction values. These results suggest that BRCA1-induced breast cancers may manifest distinct tumour biological features of clinical importance

The effects of 6 months' multimodal training on functional performance, strength, endurance, and body mass index of older individuals. Are the benefits of training similar among women and men?.

Góð hreyfigeta hefur umtalsverð áhrif á sjálfstæði og vellíðan eldra fólks. Slök hreyfigeta getur aftur á móti skert athafnir daglegs lífs. Markmið þessarar rannsóknar var að skoða áhrif 6 mánaða þjálfunar og íhlutunar á hreyfigetu karla og kvenna, hvort þjálfunin hefði ólík áhrif á kynin og hver árangur þjálfunarinnar væri 6 og 12 mánuðum eftir að henni lauk. Rannsóknin var gerð á 117 einstaklingum á aldrinum 71–90 ára sem höfðu tekið þátt í Öldrunarrannsókn Hjartaverndar. Snið rannsóknarinnar var víxlað með handahófskenndu vali í tvo hópa. Rannsóknin var gerð á þremur 6 mánaða tímabilum að loknum grunnmælingum. Sex mánaða þjálfun var þreytt af þjálfunarhópi (hópi 1) á fyrsta tímabili meðan seinni þjálfunarhópur (hópur 2) var til viðmiðunar. Hópur 2 tók síðan þátt í sams konar þjálfun á öðru tímabili en formleg þjálfun rannsóknaraðila var ekki lengur til staðar fyrir hóp 1. Sex mánuðum eftir að þjálfun hjá hópi 2 var lokið voru mælingar endurteknar í fjórða skiptið. Eftir 6 mánaða íhlutun varð 32% bæting á daglegri hreyfingu karla (p<0,001) og 39% hjá konum (p<0,001). Á hreyfigetu karla varð um 5% bæting (p<0,01) og 7% hjá konum (p<0,001). Fótkraftur karla jókst um 8% (p<0,001) og kvenna um 13% (p<0,001). Bæði karlar og konur bættu hreyfijafnvægi um 10% (p<0,001), gönguvegalengd jókst hjá báðum kynjum um 5–6% (p<0,001) og líkamsþyngdarstuðull kynjanna lækkaði um tæplega 2% (p<0,001). Enginn kynjamunur var af áhrifum þjálfunar. Heildaráhrif þjálfunar á hreyfigetu og hreyfijafnvægi héldust í allt að 12 mánuði eftir að íhlutun lauk. Fjölþætt þjálfun hefur jákvæð áhrif á hreyfigetu eldri einstaklinga, kynin bregðast á sambærilegan hátt við þjálfun og varðveita áunnar breytingar í hreyfigetu í allt að 12 mánuði. Rannsóknin bendir eindregið til þess að hófleg kerfisbundin þjálfun fyrir þennan aldurshóp ætti að vera hluti af hefðbundinni heilsugæslu aldraðra.Good functional performance in elderly people greatly improves their changes of independence and well-being. Conversely, bad functional performance can impair their capability of managing the activities of daily life.. The main goal of this study was to investigate the effects of a 6-months' multimodal training intervention on the physical performance of males and females, possible gender differences and the outcome 6 and 12 months after its completion. This study examined 71-90 year old healthy seniors (n=117) participating in the AGES Reykjavik Study. It was a randomized and controlled cross-over trial, conducted in three 6-months' phases (time-points). After enrollment and baseline assessments, the study group was divided in two. Group 1 received 6-months' training while group 2 served as a control. In the second 6 months' phase, group 1 received no formal training while group 2 did. In the third phase, neither group received training. The groups' physical conditions were assessed after each phase. After 6-months' training, 32% improvement was seen in physical activity among males (p<0.001) and 39% among females (p<0.001). In physical performance, 5% improvement was seen for males (p<0.01) and 7% for females (p<0.001). Strength increased by 8% for males (p<0.001) and 13% for females (p<0.001). For both sexes, about 10% increase was seen in dynamic balance in the 8-foot up-and-go test (p<0.001) and 5-6% in walking distance for both sexes in the six minutes walking test (p<0.001). For both sexes, body mass index decreased by about 2% (p<0.001). No difference was seen between the sexes.in the training results. Both sexes retained long-term effects of the training on physical performance and dynamic balance for at least 12 months. Multimodal training intervention has positive effects on physical performance in older individuals, the sexes respond similarly to the training and retain achieved improvement for at least 12 months. The research indicates that moderate and systemic training for this age group could be a part of conventional health service for this age group

Pollen performance before and during the autotrophic-heterotrophic transition of pollen tube growth.

For species with bicellular pollen, the attrition of pollen tubes is often greatest where the style narrows at the transition between stigmatic tissue and the transmitting tissue of the style. In this region, the tubes switch from predominantly autotrophic to predominantly heterotrophic growth, the generative cell divides, the first callose plugs are produced, and, in species with RNase-type self-incompatibility (SI), incompatible tubes are arrested. We review the literature and present new findings concerning the genetic, environmental and stylar influences on the performance of pollen before and during the autotrophic-heterotrophic transition of pollen tube growth. We found that the ability of the paternal sporophyte to provision its pollen during development significantly influences pollen performance during the autotrophic growth phase. Consequently, under conditions of pollen competition, pollen selection during the autotrophic phase is acting on the phenotype of the paternal sporophyte. In a field experiment, using Cucurbita pepo, we found broad-sense heritable variation for herbivore-pathogen resistance, and that the most resistant families produced larger and better performing pollen when the paternal sporophytes were not protected by insecticides, indicating that selection during the autotrophic phase can act on traits that are not expressed by the microgametophyte. In a study of a weedy SI species, Solanum carolinense, we found that the ability of the styles to arrest self-pollen tubes at the autotrophic-heterotrophic transition changes with floral age and the presence of developing fruits. These findings have important implications for selection at the level of the microgametophyte and the evolution of mating systems of plants

Is there a Sex Difference in Accelerometer Counts During Walking in Older Adults?

BACKGROUND: Accelerometers have emerged as a useful tool for measuring free-living physical activity in epidemiological studies. Validity of activity estimates depends on the assumption that measurements are equivalent for males and females while performing activities of the same intensity. The primary purpose of this study was to compare accelerometer count values in males and females undergoing a standardized 6-min walk test. METHODS: The study population was older adults (78.6 ± 4.1 years) from the AGES-Reykjavik Study (N = 319). Participants performed a 6-min walk test at a self-selected fast pace while wearing an ActiGraph GT3X at the hip. Vertical axis counts·s(−1) was the primary outcome. Covariates included walking speed, height, weight, BMI, waist circumference, femur length, and step length. RESULTS: On average, males walked 7.2% faster than females (1.31 vs. 1.22 m·s(−1), p < 0.001) and had 32.3% greater vertical axis counts·s(−1) (54.6 vs. 39.4 counts·s(−1), p < 0.001). Accounting for walking speed reduced the sex difference to 19.2% and accounting for step length further reduced the difference to 13.4% (p < 0.001). CONCLUSION: Vertical axis counts·s(−1) were disproportionally greater in males even after adjustment for walking speed. This difference could confound free-living activity estimates