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991.
Journal of Ethology - Many animals adjust their reproductive investment in line with their current competitive abilities. High-quality individuals may breed in the peak breeding period because they... 相似文献
992.
Matthew Walker Marta Pérez Tina Steinbrecher Frances Gawthrop Iva Pavlović Ondřej Novák Danuše Tarkowská Miroslav Strnad Federica Marone Kazumi Nakabayashi Gerhard Leubner-Metzger 《The Plant journal : for cell and molecular biology》2021,108(4):1020-1036
Underdeveloped (small) embryos embedded in abundant endosperm tissue, and thus having morphological dormancy (MD) or morphophysiological dormancy (MPD), are considered to be the ancestral state in seed dormancy evolution. This trait is retained in the Apiaceae family, which provides excellent model systems for investigating the underpinning mechanisms. We investigated Apium graveolens (celery) MD by combined innovative imaging and embryo growth assays with the quantification of hormone metabolism, as well as the analysis of hormone and cell-wall related gene expression. The integrated experimental results demonstrated that embryo growth occurred inside imbibed celery fruits in association with endosperm degradation, and that a critical embryo size was required for radicle emergence. The regulation of these processes depends on gene expression leading to gibberellin and indole-3-acetic acid (IAA) production by the embryo and on crosstalk between the fruit compartments. ABA degradation associated with distinct spatiotemporal patterns in ABA sensitivity control embryo growth, endosperm breakdown and radicle emergence. This complex interaction between gibberellins, IAA and ABA metabolism, and changes in the tissue-specific sensitivities to these hormones is distinct from non-MD seeds. We conclude that the embryo growth to reach the critical size and the associated endosperm breakdown inside MD fruits constitute a unique germination programme. 相似文献
993.
Anna Siegert Marija Rankovic Filippo Favretto Tina UkmarGodec Timo Strohker Stefan Becker Markus Zweckstetter 《Protein science : a publication of the Protein Society》2021,30(7):1326
In Parkinson''s disease with dementia, up to 50% of patients develop a high number of tau‐containing neurofibrillary tangles. Tau‐based pathologies may thus act synergistically with the α‐synuclein pathology to confer a worse prognosis. A better understanding of the relationship between the two distinct pathologies is therefore required. Liquid–liquid phase separation (LLPS) of proteins has recently been shown to be important for protein aggregation involved in amyotrophic lateral sclerosis, whereas tau phase separation has been linked to Alzheimer''s disease. We therefore investigated the interaction of α‐synuclein with tau and its consequences on tau LLPS. We find α‐synuclein to have a low propensity for both, self‐coacervation and RNA‐mediated LLPS at pH 7.4. However, full‐length but not carboxy‐terminally truncated α‐synuclein efficiently partitions into tau/RNA droplets. We further demonstrate that Cdk2‐phosphorylation promotes the concentration of tau into RNA‐induced droplets, but at the same time decreases the amount of α‐synuclein inside the droplets. NMR spectroscopy reveals that the interaction of the carboxy‐terminal domain of α‐synuclein with the proline‐rich region P2 of tau is required for the recruitment of α‐synuclein into tau droplets. The combined data suggest that the concentration of α‐synuclein into tau‐associated condensates can contribute to synergistic aSyn/tau pathologies. 相似文献
994.
Stacy A. Henry Selina Crivello Tina M. Nguyen Magdalena Cybulska Ngoc S. Hoang Mary Nguyen Tajinder Badial Nazgol Emami Nasma Awada Johnathen F. Woodward Christopher H. So 《Cell stress & chaperones》2021,26(1):187
Survival and adaptation to oxidative stress is important for many organisms, and these occur through the activation of many different signaling pathways. In this report, we showed that Caenorhabditis (C.) elegans G protein–coupled receptor kinases modified the ability of the organism to resist oxidative stress. In acute oxidative stress studies using juglone, loss-of-function grk-2 mutants were more resistant to oxidative stress compared with loss-of-function grk-1 mutants and the wild-type N2 animals. This effect was Ce-AKT-1 dependent, suggesting that Ce-GRK2 adjusted C. elegans oxidative stress resistance through the IGF/insulin-like signaling (IIS) pathway. Treating C. elegans with a GRK2 inhibitor, the selective serotonin reuptake inhibitor paroxetine, resulted in increased acute oxidative stress resistance compared with another selective serotonin reuptake inhibitor, fluoxetine. In chronic oxidative stress studies with paraquat, both grk-1 and grk-2 mutants had longer lifespan compared with the wild-type N2 animals in stress. In summary, this research showed the importance of both GRKs, especially GRK2, in modifying oxidative stress resistance. 相似文献
995.
Louise C. Kenny Tina Lavender Roseanne McNamee Sinéad M. O’Neill Tracey Mills Ali S. Khashan 《PloS one》2013,8(2)
Background
Recent decades have witnessed an increase in mean maternal age at childbirth in most high-resourced countries. Advanced maternal age has been associated with several adverse maternal and perinatal outcomes. Although there are many studies on this topic, data from large contemporary population-based cohorts that controls for demographic variables known to influence perinatal outcomes is limited.Methods
We performed a population-based cohort study using data on all singleton births in 2004–2008 from the North Western Perinatal Survey based at The University of Manchester, UK. We compared pregnancy outcomes in women aged 30–34, 35–39 and ≥40 years with women aged 20–29 years using log-linear binomial regression. Models were adjusted for parity, ethnicity, social deprivation score and body mass index.Results
The final study cohort consisted of 215,344 births; 122,307 mothers (54.19%) were aged 20–29 years, 62,371(27.63%) were aged 30–34 years, 33,966(15.05%) were aged 35–39 years and 7,066(3.13%) were aged ≥40 years. Women aged 40+ at delivery were at increased risk of stillbirth (RR = 1.83, [95% CI 1.37–2.43]), pre-term (RR = 1.25, [95% CI: 1.14–1.36]) and very pre-term birth (RR = 1.29, [95% CI:1.08–1.55]), Macrosomia (RR = 1.31, [95% CI: 1.12–1.54]), extremely large for gestational age (RR = 1.40, [95% CI: 1.25–1.58]) and Caesarean delivery (RR = 1.83, [95% CI: 1.77–1.90]).Conclusions
Advanced maternal age is associated with a range of adverse pregnancy outcomes. These risks are independent of parity and remain after adjusting for the ameliorating effects of higher socioeconomic status. The data from this large contemporary cohort will be of interest to healthcare providers and women and will facilitate evidence based counselling of older expectant mothers. 相似文献996.
Emmie de Wit Joseph Prescott Laura Baseler Trenton Bushmaker Tina Thomas Matthew G. Lackemeyer Cynthia Martellaro Shauna Milne-Price Elaine Haddock Bart L. Haagmans Heinz Feldmann Vincent J. Munster 《PloS one》2013,8(7)
In 2012 a novel coronavirus, MERS-CoV, associated with severe respiratory disease emerged in the Arabian Peninsula. To date, 55 human cases have been reported, including 31 fatal cases. Several of the cases were likely a result of human-to-human transmission. The emergence of this novel coronavirus prompts the need for a small animal model to study the pathogenesis of this virus and to test the efficacy of potential intervention strategies. In this study we explored the use of Syrian hamsters as a small animal disease model, using intratracheal inoculation and inoculation via aerosol. Clinical signs of disease, virus replication, histological lesions, cytokine upregulation nor seroconversion were observed in any of the inoculated animals, indicating that MERS-CoV does not replicate in Syrian hamsters. 相似文献
997.
Christopher K. Fairley Lenka A. Vodstrcil Sarah Huffam Rosey Cummings Marcus Y. Chen Jun K. Sze Glenda Fehler Catriona S. Bradshaw Tina Schmidt Karen Berzins Jane S. Hocking 《PloS one》2013,8(4)
Objective
Despite substantial investment in Electronic Medical Record (EMR) systems there has been little research to evaluate them. Our aim was to evaluate changes in efficiency and quality of services after the introduction of a purpose built EMR system, and to assess its acceptability by the doctors, nurses and patients using it.Methods
We compared a nine month period before and after the introduction of an EMR system in a large sexual health service, audited a sample of records in both periods and undertook anonymous surveys of both staff and patients.Results
There were 9,752 doctor consultations (in 5,512 consulting hours) in the Paper Medical Record (PMR) period and 9,145 doctor consultations (in 5,176 consulting hours in the EMR period eligible for inclusion in the analysis. There were 5% more consultations per hour seen by doctors in the EMR period compared to the PMR period (rate ratio = 1.05; 95% confidence interval, 1.02, 1.08) after adjusting for type of consultation. The qualitative evaluation of 300 records for each period showed no difference in quality (P>0.17). A survey of clinicians demonstrated that doctors and nurses preferred the EMR system (P<0.01) and a patient survey in each period showed no difference in satisfaction of their care (97% for PMR, 95% for EMR, P = 0.61).Conclusion
The introduction of an integrated EMR improved efficiency while maintaining the quality of the patient record. The EMR was popular with staff and was not associated with a decline in patient satisfaction in the clinical care provided. 相似文献998.
Mitsuaki Ono Colette A. Inkson Robert Sonn Tina M. Kilts Luis F. de Castro Azusa Maeda Larry W. Fisher Pamela G. Robey Agnes D. Berendsen Li Li Nancy McCartney-Francis Aaron C. Brown Nigel P. S. Crawford Alfredo Molinolo Alka Jain Neal S. Fedarko Marian F. Young 《PloS one》2013,8(8)
Prostate cancer (PC) is a leading cause of death in men however the factors that regulate its progression and eventual metastasis to bone remain unclear. Here we show that WISP1/CCN4 expression in prostate cancer tissues was up-regulated in early stages of the disease and, further, that it correlated with increased circulating levels of WISP1 in the sera of patients at early stages of the disease. WISP1 was also elevated in the mouse prostate cancer model TRAMP in the hypoplastic diseased tissue that develops prior to advanced carcinoma formation. When the ability of anti-WISP1 antibodies to reduce the spread of PC3-Luc cells to distant sites was tested it showed that twice weekly injections of anti-WISP1 antibodies reduced the number and overall size of distant tumors developed after intracardiac (IC) injection of PC3-Luc cells in mice. The ability of antibodies against WISP1 to inhibit growth of PC3-Luc cancer cells in mice was also evaluated and showed that twice weekly injections of anti-WISP1 antibodies reduced local tumor growth when examined in xenografts. To better understand the mechanism of action, the migration of PC3-Luc cells through membranes with or without a Matrigel™ barrier showed the cells were attracted to WISP1, and that this attraction was inhibited by treatment with anti-WISP1 antibodies. We also show the expression of WISP1 at the bone-tumor interface and in the stroma of early grade cancers suggested WISP1 expression is well placed to play roles in both fostering growth of the cancer and its spread to bone. In summary, the up-regulation of WISP1 in the early stages of cancer development coupled with its ability to inhibit spread and growth of prostate cancer cells makes it both a potential target and an accessible diagnostic marker for prostate cancer. 相似文献
999.
Hanna Regus-Leidig Corinna Ott Martina L?hner Jenny Atorf Michaela Fuchs Tina Sedmak Jan Kremers Anna Fejtová Eckart D. Gundelfinger Johann H. Brandst?tter 《PloS one》2013,8(8)
Piccolo is one of the largest cytomatrix proteins present at active zones of chemical synapses, where it is suggested to play a role in recruiting and integrating molecules relevant for both synaptic vesicle exo- and endocytosis. Here we examined the retina of a Piccolo-mutant mouse with a targeted deletion of exon 14 in the Pclo gene. Piccolo deficiency resulted in its profound loss at conventional chemical amacrine cell synapses but retinal ribbon synapses were structurally and functionally unaffected. This led to the identification of a shorter, ribbon-specific Piccolo variant, Piccolino, present in retinal photoreceptor cells, bipolar cells, as well as in inner hair cells of the inner ear. By RT-PCR analysis and the generation of a Piccolino-specific antibody we show that non-splicing of intron 5/6 leads to premature translation termination and generation of the C-terminally truncated protein specifically expressed at active zones of ribbon synapse containing cell types. With in situ proximity ligation assays we provide evidence that this truncation leads to the absence of interaction sites for Bassoon, Munc13, and presumably also ELKS/CAST, RIM2, and the L-type Ca2
+ channel which exist in the full-length Piccolo at active zones of conventional chemical synapses. The putative lack of interactions with proteins of the active zone suggests a function of Piccolino at ribbon synapses of sensory neurons different from Piccolo’s function at conventional chemical synapses. 相似文献