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141.
Anna Haywood Helene Dreau Adele Timbs Anna Schuh John Old Shirley Henderson 《Annals of hematology》2010,89(12):1215-1221
Non-deletional α+-thalassaemia is associated with a higher degree of morbidity and mortality than deletional forms of α+-thalassaemia. Screening for the common deletional forms of α-thalassaemia by Gap-PCR is widely practiced; however, the detection
of non-deletional α-thalassaemia mutations is technically more labour-intensive and expensive, as it requires DNA sequencing.
In addition, the presence of four very closely homologous alpha globin genes and the frequent co-existence of deletional forms
of α-thalassaemia present another layer of complexity in the detection of these mutations. With growing evidence that non-deletional
α-thalassaemia is relatively common in the UK, there is a demand for technologies which can quickly and accurately screen
for these mutations. We describe a method utilising pyrosequencing for detecting the ten most common clinically significant
non-deletional α-thalassaemia mutations in the UK. We tested 105 patients with non-deletional α-thalassaemia and found 100%
concordance with known genotype as identified by Sanger sequencing. We found pyrosequencing to be simpler, more robust, quicker,
and cheaper than conventional sequencing, making it a good choice for rapid and cost-effective diagnosis of patients with
suspected non-deletional α-thalassaemia. The technique is also likely to help expedite prenatal diagnosis of pregnancies at
risk of α-thalassaemia major. 相似文献
142.
Dowbiss Meta Djomsi Flaubert Auguste Mba Djonzo Innocent Ndong Bass Maëliss Champagne Audrey Lacroix Guillaume Thaurignac Amandine Esteban Helene De Nys Mathieu Bourgarel Jane-Francis Akoachere Eric Delaporte Ahidjo Ayouba Julien Cappelle Eitel Mpoudi Ngole Martine Peeters 《Viruses》2022,14(3)
The ecology of ebolaviruses is still poorly understood and the role of bats in outbreaks needs to be further clarified. Straw-colored fruit bats (Eidolon helvum) are the most common fruit bats in Africa and antibodies to ebolaviruses have been documented in this species. Between December 2018 and November 2019, samples were collected at approximately monthly intervals in roosting and feeding sites from 820 bats from an Eidolon helvum colony. Dried blood spots (DBS) were tested for antibodies to Zaire, Sudan, and Bundibugyo ebolaviruses. The proportion of samples reactive with GP antigens increased significantly with age from 0–9/220 (0–4.1%) in juveniles to 26–158/225 (11.6–70.2%) in immature adults and 10–225/372 (2.7–60.5%) in adult bats. Antibody responses were lower in lactating females. Viral RNA was not detected in 456 swab samples collected from 152 juvenile and 214 immature adult bats. Overall, our study shows that antibody levels increase in young bats suggesting that seroconversion to Ebola or related viruses occurs in older juvenile and immature adult bats. Multiple year monitoring would be needed to confirm this trend. Knowledge of the periods of the year with the highest risk of Ebolavirus circulation can guide the implementation of strategies to mitigate spill-over events. 相似文献
143.
Anna L. Alimonda Julio Núñez Eduardo Núñez Oliver Husser Juan Sanchis Vicent Bodí Gema Miñana Rocio Robles Luis Mainar Pilar Merlos Helene Darmofal Ángel Llácer 《European Journal of Internal Medicine》2009,20(1):74-79
BackgroundHyperuricemia is a prevalent condition in chronic heart failure (CHF), describing increased oxidative stress and inflammation. Although there is evidence that serum uric acid (UA) predicts mortality in CHF, its role as a prognostic biomarker in acute heart failure (AHF) has not yet been well assessed. The aim of this study was to determine if UA levels predict all-cause mortality. Additionally, as a secondary endpoint we sought the clinical predictors of UA serum level in this population.MethodsWe analyzed 560 consecutive patients with AHF admitted in a single university center. UA (mg/dl) was measured during early hospitalization. Patient survival status was followed up after discharge (median follow-up: 330 days). The independent association of UA level with all-cause mortality was analyzed using Cox regression analysis.ResultsDuring follow-up 165 (29.5%) deaths were identified. Patients with UA levels above the median value (≥ 7.7 mg/dl) exhibited higher mortality rates (21.1 vs. 37.9%; p < 0.001). In multivariable analysis, after adjusting for recognized prognostic factors and potential confounders, UA ≥ 7.7 mg/dl and per change in 1 mg/dl of UA was associated with an increased risk of mortality (HR 1.45, CI 95% = 1.03–2.44; p = 0.03 and HR 1.08, CI 95% = 1.01–1.15; p = 0.03, respectively).ConclusionUA serum levels is an independent predictor of all-cause mortality in an unselected patients admitted with AHF. 相似文献
144.
Ischemic stroke triggers a massive, although transient, glutamate efflux and excessive activation of NMDA receptors (NMDARs), possibly leading to neuronal death. However, multiple clinical trials with NMDA antagonists failed to improve, or even worsened, stroke outcome. Recent findings of a persistent post-stroke decline in NMDAR density, which plays a pivotal role in plasticity and memory formation, suggest that NMDAR stimulation, rather than inhibition, may prove beneficial in the subacute period after stroke. AIM: This study aims to examine the effect of the NMDAR partial agonist d-cycloserine (DCS) on long-term structural, functional and behavioral outcomes in rats subjected to transient middle cerebral artery occlusion, an animal model of ischemic stroke. MATERIALS #ENTITYSTARTX00026; METHODS: Rats (n = 36) that were subjected to 90 min of middle cerebral artery occlusion were given a single injection of DCS (10 mg/kg) or vehicle (phosphate-buffered saline) 24 h after occlusion and followed up for 30 days. MRI (structural and functional) was used to measure infarction, atrophy and cortical activation due to electrical forepaw stimulation. Memory function was assessed on days 7, 21 and 30 postocclusion using the novel object recognition test. A total of 20 nonischemic controls were included for comparison. RESULTS: DCS treatment resulted in significant improvement of somatosensory and cognitive function relative to vehicle treatment. By day 30, cognitive performance of the DCS-treated animals was indistinguishable from nonischemic controls, while vehicle-treated animals demonstrated a stable memory deficit. DCS had no significant effect on infarction or atrophy. CONCLUSION: These results support a beneficial role for NMDAR stimulation during the recovery period after stroke, most likely due to enhanced neuroplasticity rather than neuroprotection. 相似文献
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147.
The idea behind this article is to discuss the importance and to develop the concept of reciprocity in asymmetric professional relationships. As an empirical starting point for an examination of the possible forms of reciprocity between patients and nurses in psychiatry, we chose two qualitative in-depth interviews with two different patients. The manners in which these two patients relate to medical personnel??one is dependent, the other is independent??show that this presents challenges to nurses. The theoretical context is provided by the notion of mature care as it has been developed by feminist-oriented ethics of care, in contrast to the notion of altruistic care. In relation to the concept of mature care, we discuss how nursing can be perceived in demanding relationships with patients in psychiatry. Reciprocity implies that, in principle, the interests of the nurses also matter in a nurse-patient relationship. We show that reciprocity??in practice??is complicated and challenging in a number of different ways. Mature care??with its systematic inclusion of relationships and reciprocity??provides an alternative understanding of what takes place between patients and nurses compared with an altruistic notion of care. As such, mature care can be regarded as an useful paradigm for nurse-patient relationships in psychiatry. 相似文献
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150.
Jing Tian Carrie Paquette-Straub E Helene Sage Sarah E Funk Vivek Patel Deni Galileo Mary Ann McLane 《Toxicon》2007,49(7):899-908
Eristostatin, an RGD-containing disintegrin isolated from the venom of Eristicophis macmahoni, inhibits lung or liver colonization of melanoma cells in a mouse model. In this study, transwell migration and in vitro wound closure assays were used to determine the effect of eristostatin on the migration of melanoma cells. Eristostatin significantly impaired the migration of five human melanoma cell lines. Furthermore, it specifically inhibited cell migration on fibronectin in a concentration-dependent manner, but not that on collagen IV or laminin. In contrast, eristostatin was found to have no effect on cell proliferation or angiogenesis. These results indicate that the interaction between eristostatin and melanoma cells may involve fibronectin-binding integrins that mediate cell migration. Mutations to alanine of seven residues within the RGD loop of eristostatin and four residues outside the RGD loop of eristostatin resulted in significantly less potency in both platelet aggregation and wound closure assays. For six of the mutations, however, decreased activity was found only in the latter assay. We conclude that a different mechanism and/or integrin is involved in these two cell activities. 相似文献