363 research outputs found
Peroxisome Proliferator-Activated Receptor alpha (PPAR alpha) down-regulation in cystic fibrosis lymphocytes
Background: PPARs exhibit anti-inflammatory capacities and are potential modulators of the inflammatory response. We hypothesized that their expression and/or function may be altered in cystic fibrosis (CF), a disorder characterized by an excessive host inflammatory response.
Methods: PPARα, β and γ mRNA levels were measured in peripheral blood cells of CF patients and healthy subjects via RT-PCR. PPARα protein expression and subcellular localization was determined via western blot and immunofluorescence, respectively. The activity of PPARα was analyzed by gel shift assay.
Results: In lymphocytes, the expression of PPARα mRNA, but not of PPARβ, was reduced (-37%; p < 0.002) in CF patients compared with healthy persons and was therefore further analyzed. A similar reduction of PPARα was observed at protein level (-26%; p < 0.05). The transcription factor was mainly expressed in the cytosol of lymphocytes, with low expression in the nucleus. Moreover, DNA binding activity of the transcription factor was 36% less in lymphocytes of patients (p < 0.01). For PPARα and PPARβ mRNA expression in monocytes and neutrophils, no significant differences were observed between CF patients and healthy persons. In all cells, PPARγ mRNA levels were below the detection limit.
Conclusion: Lymphocytes are important regulators of the inflammatory response by releasing cytokines and antibodies. The diminished lymphocytic expression and activity of PPARα may therefore contribute to the inflammatory processes that are observed in CF
C4 photosynthesis boosts growth by altering physiology, allocation and size.
C4 photosynthesis is a complex set of leaf anatomical and biochemical adaptations that have evolved more than 60 times to boost carbon uptake compared with the ancestral C3 photosynthetic type(1-3). Although C4 photosynthesis has the potential to drive faster growth rates(4,5), experiments directly comparing C3 and C4 plants have not shown consistent effects(1,6,7). This is problematic because differential growth is a crucial element of ecological theory(8,9) explaining C4 savannah responses to global change(10,11), and research to increase C3 crop productivity by introducing C4 photosynthesis(12). Here, we resolve this long-standing issue by comparing growth across 382 grass species, accounting for ecological diversity and evolutionary history. C4 photosynthesis causes a 19-88% daily growth enhancement. Unexpectedly, during the critical seedling establishment stage, this enhancement is driven largely by a high ratio of leaf area to mass, rather than fast growth per unit leaf area. C4 leaves have less dense tissues, allowing more leaves to be produced for the same carbon cost. Consequently, C4 plants invest more in roots than C3 species. Our data demonstrate a general suite of functional trait divergences between C3 and C4 species, which simultaneously drive faster growth and greater investment in water and nutrient acquisition, with important ecological and agronomic implications
TRY plant trait database - enhanced coverage and open access
Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives
Biological Role and Clinical Implications of MYOD1L122R Mutation in Rhabdomyosarcoma
Major progress in recent decades has furthered our clinical and biological understanding of rhabdomyosarcoma (RMS) with improved stratification for treatment based on risk factors. Clinical risk factors alone were used to stratify patients for treatment in the European Pediatric Soft Tissue Sarcoma Study Group (EpSSG) RMS 2005 protocol. The current EpSSG overarching study for children and adults with frontline and relapsed rhabdomyosarcoma (FaR-RMS NCT04625907) includes FOXO1 fusion gene status in place of histology as a risk factor. Additional molecular features of significance have recently been recognized, including the MYOD1L122R gene mutation. Here, we review biological information showing that MYOD1L122R blocks cell differentiation and has a MYC-like activity that enhances tumorigenesis and is linked to an aggressive cellular phenotype. MYOD1L122R mutations can be found together with mutations in other genes, such as PIK3CA, as potentially cooperating events. Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, ten publications in the clinical literature involving 72 cases were reviewed. MYOD1L122R mutation in RMS can occur in both adults and children and is frequent in sclerosing/spindle cell histology, although it is also significantly reported in a subset of embryonal RMS. MYOD1L122R mutated tumors most frequently arise in the head and neck and extremities and are associated with poor outcome, raising the issue of how to use MYOD1L122R in risk stratification and how to treat these patients most effectively
A behavioral database for masked form priming
Reading involves a process of matching an orthographic input with stored representations in lexical memory. The masked priming paradigm has become a standard tool for investigating this process. Use of existing results from this paradigm can be limited by the precision of the data and the need for cross-experiment comparisons that lack normal experimental controls. Here, we present a single, large, high-precision, multicondition experiment to address these problems. Over 1,000 participants from 14 sites responded to 840 trials involving 28 different types of orthographically related primes (e.g., castfe–CASTLE) in a lexical decision task, as well as completing measures of spelling and vocabulary. The data were indeed highly sensitive to differences between conditions: After correction for multiple comparisons, prime type condition differences of 2.90 ms and above reached significance at the 5% level. This article presents the method of data collection and preliminary findings from these data, which included replications of the most widely agreed-upon differences between prime types, further evidence for systematic individual differences in susceptibility to priming, and new evidence regarding lexical properties associated with a target word’s susceptibility to priming. These analyses will form a basis for the use of these data in quantitative model fitting and evaluation and for future exploration of these data that will inform and motivate new experiments
Clinical symptoms and chemotherapy completion in elderly patients with newly diagnosed acute leukemia: a retrospective comparison study with a younger cohort
<p>Abstract</p> <p>Background</p> <p>Cancer affects older adults disproportionately. The disease is often difficult to diagnose and treat due to co-morbidities and performance status, and patients tend to discontinue chemotherapy prematurely. There are no systemic studies of the reasons and factors that create a higher withdrawal rate in older acute leukemia patients. This study tried to understand the initial characteristics, blood counts and bone marrow measurements in older acute leukemia patients by comparing them with a younger group to provide information and assistance in early clinical diagnosis, treatment and reasons for treatment withdrawal.</p> <p>Methods</p> <p>Using retrospective medical record reviews, we examined clinical characteristics and chemotherapy completion status in the patients of two groups (age ≥ 60, n = 183 and age <60, n = 183) who were diagnosed with acute leukemia for the first time and were hospitalized in Union Hospital Affiliated with Fujian Medical University from 2004 to 2008.</p> <p>Results</p> <p>There were no statistical differences in initial presenting symptoms of fatigue (67.2% vs. 57.9%, <it>P</it>>0.05) and pallor (53% vs. 59.6%, <it>P</it>>0.05) between the two groups, but older patients demonstrated more underlying diseases including lung infections (25.7%, <it>P </it>= <0.001), cardiovascular disease (4.4%, <it>P </it>= 0.007), and hypertension (20.8%, <it>P </it>=< 0.001). The complete remission rate after chemotherapy (1 to 2 courses) was 49.5% in the older group and 66.7% in the younger group (χ<sup>2 </sup>= 6.202, <it>P </it>= 0.013). The percentage of patients age 60 and older who prematurely discontinued chemotherapy (50.3%), mainly due to the influences of traditional Chinese concept of critical illness, financial difficulties, and intolerance to adverse reactions to chemotherapy, was significantly higher than that of younger patients (37.7%) (χ<sup>2 </sup>= 5.866, <it>P </it>= 0.015).</p> <p>Conclusions</p> <p>A comprehensive approach to diagnosis, treatment selection, and toxicity management, and implementing strategies to enhance treatment compliance may improve outcomes in older adults with acute leukemia.</p
Salvage Cryotherapy for Radiation-Recurrent Prostate Cancer: Outcomes and Complications
Potentially curative salvage options for radio-recurrent prostate cancer include prostatectomy, brachytherapy, high-intensity focused ultrasound, and cryotherapy. Salvage cryoablation technology, surgical technique, oncologic outcomes, and complication rates have improved dramatically over the past few decades, shifting this treatment modality from investigational status to an established therapeutic option. In this review, we focus on the most up-to-date oncologic and functional outcomes, as well as complications of salvage cryotherapy for radiation-recurrent prostate cancer
Detection of the PAX3-FKHR fusion gene in paediatric rhabdomyosarcoma: a reproducible predictor of outcome?
Rhabdomyosarcoma has 2 major histological subtypes, embryonal and alveolar. Alveolar histology is associated with the fusion genes PAX3-FKHR and PAX7-FKHR. Definition of alveolar has been complicated by changes in terminology and subjectivity. It is currently unclear whether adverse clinical behaviour is better predicted by the presence of these fusion genes or by alveolar histology. We have determined the presence of the PAX3/7-FKHR fusion genes in 91 primary rhabdomyosarcoma tumours using a combination of classical cytogenetics, FISH and RT-PCR, with a view to determining the clinical characteristics of tumours with and without the characteristic translocations. There were 37 patients with t(2;13)/PAX3-FKHR, 8 with t(1;13) PAX7-FKHR and 46 with neither translocation. One or other of the characteristic translocations was found in 31/38 (82%) of alveolar cases. Univariate survival analysis revealed the presence of the translocation t(2;13)/PAX3-FKHR to be an adverse prognostic factor. With the difficulties in morphological diagnosis of alveolar rhabdomyosarcoma on increasingly used small needle biopsy specimens, these data suggest that molecular analysis for PAX3-FKHR will be a clinically useful tool in treatment stratification in the future. This hypothesis requires testing in a prospective study. Variant t(1;13)/PAX7-FKHR appears biologically different, occurring in younger patients with more localised disease. © 2001 Cancer Research Campaignhttp://www.bjcancer.co
Molecular analysis of human endometrium: short-term tibolone signaling differs significantly from estrogen and estrogen + progestagen signaling
Tibolone, a tissue-selective compound with a combination of estrogenic, progestagenic, and androgenic properties, is used as an alternative for estrogen or estrogen plus progesterone hormone therapy for the treatment of symptoms associated with menopause and osteoporosis. The current study compares the endometrial gene expression profiles after short-term (21 days) treatment with tibolone to the profiles after treatment with estradiol-only (E2) and E2 + medroxyprogesterone acetate (E2 + MPA) in healthy postmenopausal women undergoing hysterectomy for endometrial prolapse. The impact of E2 treatment on endometrial gene expression (799 genes) was much higher than the effect of tibolone (173 genes) or E2 + MPA treatment (174 genes). Furthermore, endometrial gene expression profiles after tibolone treatment show a weak similarity to the profiles after E2 treatment (overlap 72 genes) and even less profile similarity to E2 + MPA treatment (overlap 17 genes). Interestingly, 95 tibolone-specific genes were identified. Translation of profile similarity into biological processes and pathways showed that ER-mediated downstream processes, such as cell cycle and cell proliferation, are not affected by E2 + MPA, slightly by tibolone, but are significantly affected by E2. In conclusion, tibolone treatment results in a tibolone-specific gene expression profile in the human endometrium, which shares only limited resemblance to E2 and even less resemblance to E2 + MPA induced profiles
Increased searching and handling effort in tall swards lead to a Type IV functional response in small grazing herbivores
Understanding the functional response of species is important in comprehending the species’ population dynamics and the functioning of multi-species assemblages. A Type II functional response, where instantaneous intake rate increases asymptotically with sward biomass, is thought to be common in grazers. However, at tall, dense swards, food intake might decline due to mechanical limitations or if animals selectively forage on the most nutritious parts of a sward, leading to a Type IV functional response, especially for smaller herbivores. We tested the predictions that bite mass, cropping time, swallowing time and searching time increase, and bite rate decreases with increasing grass biomass for different-sized Canada geese (Branta canadensis) foraging on grass swards. Bite mass indeed showed an increasing asymptotic relationship with grass biomass. At high biomass, difficulties in handling long leaves and in locating bites were responsible for increasing cropping, swallowing, and searching times. Constant bite mass and decreasing bite rate caused the intake rate to decrease at high sward biomass after reaching an optimum, leading to a Type IV functional response. Grazer body mass affected maximum bite mass and intake rate, but did not change the shape of the functional response. As grass nutrient contents are usually highest in short swards, this Type IV functional response in geese leads to an intake rate that is maximised in these swards. The lower grass biomass at which intake rate was maximised allows resource partitioning between different-sized grazers. We argue that this Type IV functional response is of more importance than previously thought
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