433 research outputs found

    The Batten disease protein CLN3 is important for stress granules dynamics and translational activity

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    The assembly of membrane-less organelles such as stress granules (SGs) is emerging as central in helping cells rapidly respond and adapt to stress. Following stress sensing, the resulting global translational shutoff leads to the condensation of stalled mRNAs and proteins into SGs. By reorganizing cytoplasmic contents, SGs can modulate RNA translation, biochemical reactions, and signaling cascades to promote survival until the stress is resolved. While mechanisms for SG disassembly are not widely understood, the resolution of SGs is important for maintaining cell viability and protein homeostasis. Mutations that lead to persistent or aberrant SGs are increasingly associated with neuropathology and a hallmark of several neurodegenerative diseases. Mutations in CLN3 are causative of juvenile neuronal ceroid lipofuscinosis, a rare neurodegenerative disease affecting children also known as Batten disease. CLN3 encodes a transmembrane lysosomal protein implicated in autophagy, endosomal trafficking, metabolism, and response to oxidative stress. Using a HeLa cell model lacking CLN3, we now show that CLN3KO is associated with an altered metabolic profile, reduced global translation, and altered stress signaling. Furthermore, loss of CLN3 function results in perturbations in SG dynamics, resulting in assembly and disassembly defects, and altered expression of the key SG nucleating factor G3BP1. With a growing interest in SG-modulating drugs for the treatment of neurodegenerative diseases, novel insights into the molecular basis of CLN3 Batten disease may reveal avenues for disease-modifying treatments for this debilitating childhood disease

    Sexuality and Affection among Elderly German Men and Women in Long-Term Relationships: Results of a Prospective Population-Based Study

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    This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.The study was funded by the German Federal Ministry for Families, Senior Citizens, Women and Youth (AZ 314-1722-102/16; AZ 301-1720-295/2), the Ministry for Science, Research and Art Baden-Württemberg, and the University of Rostock (FORUN 989020; 889048)

    Automated Defect Detection For Masonry Arch Bridges

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    The condition of masonry arch bridges is predominantly monitored with manual visual inspection. This process has been found to be subjective, relying on an inspection engineer’s interpretation of the condition of the structure. This paper initially presents a workflow that has been developed that can be used by a future automated bridge monitoring system to determine underlying faults in a bridge and suggest appropriate remedial action based on a set of detectable symptoms. This workflow has been used to identify the main classes of defects that an automated visual detection system for masonry should be capable of detecting. Subsequently, a convolutional neural network is used to classify these identified defect classes from images of masonry. As the mortar joints in the masonry are more distinctive than the defects being sought, their effect on the performance of an automated defect classifier is investigated. Compared to classifying all the regions of the masonry with a single classifier, it is found that where the mortar and brick regions have been classified separately, defect and defect free areas of the masonry have been predicted both with more confidence and with better accuracy

    Behaviourally Mediated Phenotypic Selection in a Disturbed Coral Reef Environment

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    Natural and anthropogenic disturbances are leading to changes in the nature of many habitats globally, and the magnitude and frequency of these perturbations are predicted to increase under climate change. Globally coral reefs are one of the most vulnerable ecosystems to climate change. Fishes often show relatively rapid declines in abundance when corals become stressed and die, but the processes responsible are largely unknown. This study explored the mechanism by which coral bleaching may influence the levels and selective nature of mortality on a juvenile damselfish, Pomacentrus amboinensis, which associates with hard coral. Recently settled fish had a low propensity to migrate small distances (40 cm) between habitat patches, even when densities were elevated to their natural maximum. Intraspecific interactions and space use differ among three habitats: live hard coral, bleached coral and dead algal-covered coral. Large fish pushed smaller fish further from the shelter of bleached and dead coral thereby exposing smaller fish to higher mortality than experienced on healthy coral. Small recruits suffered higher mortality than large recruits on bleached and dead coral. Mortality was not size selective on live coral. Survival was 3 times as high on live coral as on either bleached or dead coral. Subtle behavioural interactions between fish and their habitats influence the fundamental link between life history stages, the distribution of phenotypic traits in the local population and potentially the evolution of life history strategies

    Treatments for irritable bowel syndrome: patients' attitudes and acceptability

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    <p>Abstract</p> <p>Background</p> <p>Irritable Bowel Syndrome, a highly prevalent chronic disorder, places significant burden on the health service and the individual. Symptomatic distress and reduced quality of life are compounded by few efficacious treatments available. As researchers continue to demonstrate the clinical efficacy of alternative therapies, it would be useful to gain a patient-perspective of treatment acceptability and identify patient's attitudes towards those modalities considered not acceptable.</p> <p>Methods</p> <p>Six hundred and forty-five participants identified from an earlier IBS-prevalence study received a postal questionnaire to evaluate preferences and acceptability of nine forms of treatment. Proportions accepting each form of treatment were calculated and thematic analysis of qualitative data undertaken.</p> <p>Results</p> <p>A total of 256 (39.7%) of 645 potential respondents completed the questionnaire (mean age 55.9 years, 73% female). Tablets were most acceptable (84%), followed by lifestyle changes (diet (82%), yoga (77%)). Acupuncture (59%) and suppositories (57%) were less acceptable.</p> <p>When explaining lack of acceptability, patient views fell into four broad categories: dislike treatment modality, do not perceive benefit, general barriers and insufficient knowledge. Scepticism, lack of scientific rationale and fear of CAM were mentioned, although others expressed a dislike of conventional medical treatments. Past experiences, age and health concerns, and need for proof of efficacy were reported.</p> <p>Conclusion</p> <p>Most patients were willing to accept various forms of treatment. However, the reservations expressed by this patient-population must be recognised with particular focus directed towards allaying fears and misconceptions, seeking further evidence base for certain therapies and incorporating physician support and advice.</p

    Malaria associated symptoms in pregnant women followed-up in Benin

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    <p>Abstract</p> <p>Background</p> <p>It is generally agreed that in high transmission areas, pregnant women have acquired a partial immunity to malaria and when infected they present few or no symptoms. However, longitudinal cohort studies investigating the clinical presentation of malaria infection in pregnant women in stable endemic areas are lacking, and the few studies exploring this issue are unconclusive.</p> <p>Methods</p> <p>A prospective cohort of women followed monthly during pregnancy was conducted in three rural dispensaries in Benin from August 2008 to September 2010. The presence of symptoms suggestive of malaria infection in 982 women during antenatal visits (ANV), unscheduled visits and delivery were analysed. A multivariate logistic regression was used to determine the association between symptoms and a positive thick blood smear (TBS).</p> <p>Results</p> <p>During routine ANVs, headache was the only symptom associated with a higher risk of positive TBS (aOR = 1.9; p < 0.001). On the occasion of unscheduled visits, fever (aOR = 5.2; p < 0.001), headache (aOR = 2.1; p = 0.004) and shivering (aOR = 3.1; p < 0.001) were significantly associated with a malaria infection and almost 90% of infected women presented at least one of these symptoms. Two thirds of symptomatic malaria infections during unscheduled visits occurred in late pregnancy and long after the last intermittent preventive treatment dose (IPTp).</p> <p>Conclusion</p> <p>The majority of pregnant women were symptomless during routine visits when infected with malaria in an endemic stable area. The only suggestive sign of malaria (fever) was associated with malaria only on the occasion of unscheduled visits. The prevention of malaria in pregnancy could be improved by reassessing the design of IPTp, i.e. by determining an optimal number of doses and time of administration of anti-malarial drugs.</p

    Constitutive expression of ftsZ overrides the whi developmental genes to initiate sporulation of Streptomyces coelicolor

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    The filamentous soil bacteria Streptomyces undergo a highly complex developmental programme. Before streptomycetes commit themselves to sporulation, distinct morphological checkpoints are passed in the aerial hyphae that are subject to multi-level control by the whi sporulation genes. Here we show that whi-independent expression of FtsZ restores sporulation to the early sporulation mutants whiA, whiB, whiG, whiH, whiI and whiJ. Viability, stress resistance and high-resolution electron microscopy underlined that viable spores were formed. However, spores from sporulation-restored whiA and whiG mutants showed defects in DNA segregation/condensation, while spores from the complemented whiB mutant had increased stress sensitivity, perhaps as a result of changes in the spore sheath. In contrast to the whi mutants, normal sporulation of ssgB null mutants—which fail to properly localise FtsZ—could not be restored by enhancing FtsZ protein levels, forming spore-like bodies that lack spore walls. Our data strongly suggest that the whi genes control a decisive event towards sporulation of streptomycetes, namely the correct timing of developmental ftsZ transcription. The biological significance may be to ensure that sporulation-specific cell division will only start once sufficient aerial mycelium biomass has been generated. Our data shed new light on the longstanding question as to how whi genes control sporulation, which has intrigued scientists for four decades

    Lack of correlation between Ki-67 labelling index and tumor size of anterior pituitary adenomas

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    AIMS AND BACKGROUND: The Ki-67 is a nuclear antigen detected by the monoclonal antibody MIB-1 and its Labeling Index (LI) is considered a marker of normal and abnormal cell proliferation. Pituitary adenomas are generally well differentiated neoplasms, even if in about one third of cases they are invasive of surrounding tissues. The aim of this study is to evaluate the correlation between Ki-67 labelling index and tumor size of pituitary adenomas extimated by means CT and MRI and confirmed at operation. METHODS: Using the monoclonal antibody MIB-1, we evaluated the expression of Ki-67 in 121 anterior pituitary adenomas consecutively operated on in a 48-month period. RESULTS: In relation to neuroradiological (CT and MRI) and surgically verified tumor size, we identified 24 microadenomas, 27 intrasellar macroadenomas, 34 intra-suprasellar macroadenomas, and 36 intra-supra-parasellar macroadenomas. The adenomas were non-infiltrating (76 cases) and infiltrating (45 cases) adenomas. The wall of the cavernous sinus (CS) was infiltrated in 18 cases. Forty-eight adenomas were non-functioning and 73 functioning. The overall mean ± SD Ki-67 LI was 2.72 ± 2.49% (median 1.6). It was 2.59 ± 1.81 in microadenomas, 2.63 ± 3.45 in intrasellar macroadenomas, 1.91 ± 2.11 in intra-suprasellar macroadenomas, and 3.29 ± 5.45 in intra-supra-parasellar macroadenomas (p = 0.27). It was 3.73 ± 5.13% in infiltrating and 2.03 ± 2.41% in non-infiltrating adenomas (p = 0.02), and 5.61 ± 7.19% in CS-infiltrating versus 2.09 ± 2.37% in CS-non-infiltrating adenomas (p = 0.0005). CONCLUSIONS: Our preliminary results seem to exclude significative correlations between Ki-67 LI and tumor size of anterior pituitary adenomas, even if this index can be considered a useful marker in the determination of the infiltrative behaviour of these tumors

    A Gammaherpesviral Internal Repeat Contributes to Latency Amplification

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    BACKGROUND: Gammaherpesviruses cause important infections of humans, in particular in immunocompromised patients. The genomes of gammaherpesviruses contain variable numbers of internal repeats whose precise role for in vivo pathogenesis is not well understood. METHODOLOGY/PRINCIPAL FINDINGS: We used infection of laboratory mice with murine gammaherpesvirus 68 (MHV-68) to explore the biological role of the 40 bp internal repeat of MHV-68. We constructed several mutant viruses partially or completely lacking this repeat. Both in vitro and in vivo, the loss of the repeat did not substantially affect lytic replication of the mutant viruses. However, the extent of splenomegaly, which is associated with the establishment of latency, and the number of ex vivo reactivating and genome positive splenocytes were reduced. Since the 40 bp repeat is part of the hypothetical open reading frame (ORF) M6, it might function as part of M6 or as an independent structure. To differentiate between these two possibilities, we constructed an N-terminal M6STOP mutant, leaving the repeat structure intact but rendering ORF M6 unfunctional. Disruption of ORF M6 did neither affect lytic nor latent infection. In contrast to the situation in lytically infected NIH3T3 cells, the expression of the latency-associated genes K3 and ORF72 was reduced in the latently infected murine B cell line Ag8 in the absence of the 40 bp repeat. CONCLUSIONS/SIGNIFICANCE: These data suggest that the 40 bp repeat contributes to latency amplification and might be involved in the regulation of viral gene expression
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