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671.
L. Kluwe Saskia Bayer M. E. Baser Wasim Hazim Wolfgang Haase Carsten Fünsterer V.-F. Mautner 《Human genetics》1996,98(5):534-538
Neurofibromatosis 2 (NF2) is an autosomal inherited disorder that predisposes carriers to nervous system tumors. To examine
genotype-phenotype correlations in NF2, we performed mutation analyses and gadolinium-enhanced magnetic resonance imaging
of the head and full spine in 59 unrelated NF2 patients. In patients with vestibular schwannomas (VSs) or identified NF2 mutations, the mild phenotype was defined as <2 other intracranial tumors and ≤ 4 spinal tumors, and the severe phenotype
as either ≥ 2 other intracranial tumors or > 4 spinal tumors. Nineteen mutations were found in 20 (34%) of the patients and
were distributed in 12 of the 17 exons of the NF2 gene, including intron-exon boundaries. Seven mutations were frameshift, six were nonsense, four were splice site, two were
missense, and one was a 3-bp in frame deletion. The nonsense mutations included one codon 57 and two codon 262 C→T transitions
in CpG dinucleotides. The frameshift and nonsense NF2 mutations occurred primarily in patients with severe phenotypes. The two missense mutations occurred in patients with mild
phenotypes, and three of the four splice site mutations occurred in families with both mild and severe phenotypes. Truncating
NF2 mutations are usually associated with severe phenotypes, but the association of some mutations with mild and severe phenotypes
indicates that NF2 expression is influenced by stochastic, epigenetic, or environmental factors.
Received: 4 July 1996 相似文献
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Jan Wilke Florian Giesche Daniel Niederer Tobias Engeroff Sebastian Barabas Saskia Trller Lutz Vogt Winfried Banzer 《Biology of sport / Institute of Sport》2021,38(1):123
Failed jump landings represent a key mechanism of musculoskeletal trauma. It has been speculated that cognitive dual-task loading during the flight phase may moderate the injury risk. This study aimed to explore whether increased visual distraction can compromise landing biomechanics. Twenty-one healthy, physically active participants (15 females, 25.8 ± 0.4 years) completed a series of 30 counter-movement jumps (CMJ) onto a capacitive pressure platform. In addition to safely landing on one leg, they were required to memorize either one, two or three jersey numbers shown during the flight phase (randomly selected and equally balanced over all jumps). Outcomes included the number of recall errors as well as landing errors and three variables of landing kinetics (time to stabilization/TTS, peak ground reaction force/pGRF, length of the centre of pressure trace/COPT). Differences between the conditions were calculated using the Friedman test and the post hoc Bonferroni-Holm corrected Wilcoxon test. Regardless of the condition, landing errors remained unchanged (p = .46). In contrast, increased visual distraction resulted in a higher number of recall errors (chi2 = 13.3, p = .001). Higher cognitive loading, furthermore, appeared to negatively impact mediolateral COPT (p < .05). Time to stabilization (p = .84) and pGRF (p = .78) were unaffected. A simple visual distraction in a controlled experimental setting is sufficient to adversely affect landing stability and task-related short-term memory during CMJ. The ability to precisely perceive the environment during movement under time constraints may, hence, represent a new injury risk factor and should be investigated in a prospective trial. 相似文献
675.
Saskia De Raad Michelle Comte Patrick Nef Stefan E. Lenz Eckart D. Gundelfinger Jos A. Cox 《The Histochemical journal》1995,27(7):524-535
Summary Neural Ca2+-binding proteins (NCaPs) constitute a subfamily of 4-EF-hand proteins, and display a histological and structural dichotomy:
the A-type NCaPs are selectively expressed by the retina and pineal organ and display two canonical EF-hands, whereas the
B-type NCaPs are found in the entire brain and present three regular EF-hands. In this study, antisera were raised against
the A-type NCaP recoverin (26 kDa) and the B-type NCaPs VILIP and NCS-1 (22 kDa). Since the sequence identity among NCaPs
is high, specific polyclonal antibodies were purified by double cross-immunoaffinity chromatography; both ELISA and immunoblot
analyses determined that the resulting antibodies showed selectivity ratios inferior to 1/363 for the two other related NCaPs.
Besides, the anti-VILIP antibodies displayed some affinity toward neurocalcin δ, and the antirecoverin antibodies recognized
a 24 kDa protein, which is most likely visinin. Thus, immunohistochemical studies on the chicken, rat and cow retina revealed
that anti-recoverin antibodies recognized the vertebrate photoreceptors and a small number of mammalian bipolar cells. Anti-VILIP
antibodies exclusively labelled the inner Retina, I.e. the amacrine and ganglion cells. NCS-1 was mainly present in the photoreceptor
inner segments, the inner plexiform layer and the ganglion cells. NCS-1 showed the highest species disparity. The retinal
localization of NCS-1 and VILIP offered an important morphological basis for the understanding of their function. Furthermore,
specific antibodies against the NCaPs may enable the identification of cell populations in more complex neural tissues, such
as the brain. 相似文献
676.
Sofia Adolfsson Yannis Michalakis Dorota Paczesniak Saskia N. S. Bode Roger K. Butlin Dunja K. Lamatsch Maria J. F. Martins Olivier Schmit Jochen Vandekerkhove Jukka Jokela 《Evolution; international journal of organic evolution》2010,64(4):986-997
Transitions from sexual to asexual reproduction are often coupled with elevations in ploidy. As a consequence, the importance of ploidy per se for the maintenance and spread of asexual populations is unclear. To examine the effects of ploidy and asexual reproduction as independent determinants of the success of asexual lineages, we sampled diploid sexual, diploid asexual, and triploid asexual Eucypris virens ostracods across a European wide range. Applying nuclear and mitochondrial markers, we found that E. virens consists of genetically highly differentiated diploid sexual populations, to the extent that these sexual clades could be considered as cryptic species. All sexual populations were found in southern Europe and North Africa and we found that both diploid asexual and triploid asexual lineages have originated multiple times from several sexual lineages. Therefore, the asexual lineages show a wide variety of genetic backgrounds and very strong population genetic structure across the wide geographic range. Finally, we found that triploid, but not diploid, asexual clones dominate habitats in northern Europe. The limited distribution of diploid asexual lineages, despite their shared ancestry with triploid asexual lineages, strongly suggests that the wider geographic distribution of triploids is due to elevated ploidy rather than to asexuality. 相似文献
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Many societies have been recently exposed to humanitarian and health emergencies, which have resulted in a large number of people experiencing significant distress and being at risk to develop mental disorders such as depression, anxiety and post-traumatic stress disorder. The World Health Organization has released a series of scalable psychosocial interventions for people impaired by distress in communities exposed to adversities. Prominent among these is a low-intensity transdiagnostic psychosocial intervention, Problem Management Plus (PM+), and its digital adaptation Step-by-Step (SbS). This systematic review is the first to summarize the available evidence on the effects of PM+ and SbS. Up to March 8, 2023, five databases were searched for randomized controlled trials examining the effects of PM+ or SbS on distress indicators (i.e., general distress; anxiety, depressive or post-traumatic stress disorder symptoms; functional impairment, self-identified problems) and positive mental health outcomes (i.e., well-being, quality of life, social support/relationships). We performed random-effects multilevel meta-analyses on standardized mean differences (SMDs) at post-intervention and short-term follow-up assessments. Our search yielded 23 eligible studies, including 5,298 participants. We found a small to medium favorable effect on distress indicators (SMD=–0.45, 95% CI: –0.56 to –0.34) and a small beneficial effect on positive mental health outcomes (SMD=0.31, 95% CI: 0.14-0.47), which both remained significant at follow-up assessment and were robust in sensitivity analyses. However, our analyses pointed to substantial between-study heterogeneity, which was only partially explained by moderators, and the certainty of evidence was very low across all outcomes. These results provide evidence for the effectiveness of PM+ and SbS in reducing distress indicators and promoting positive mental health in populations exposed to adversities, but a larger high-quality evidence base is needed, as well as research on participant-level moderators of the effects of these interventions, their suitability for stepped-care programs, and their cost-effectiveness. 相似文献
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