932 resultados para BLOOD-BRAIN-BARRIER


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Aims: After failure of anthracycline- and taxane-based chemotherapy in metastatic breast cancer, treatment options until recently were limited. Until the introduction of capecitabine and vinorelbine, no standard regimen was available. We conducted a retrospective study to determine the efficacy and toxicity of platinum-based chemotherapy in metastatic breast cancer. Materials and methods: Forty-two women with metastatic breast cancer previously treated with anthracyclines (93%) and/or taxanes (36%) received mitomycin-vinblastine-cisplatin (MVP) (n = 23), or cisplatin-etoposide (PE) (n = 19), as first-, second- and third-line treatment at a tertiary referral centre between 1997 and 2002. Chemotherapy was given every 3 weeks as follows: mitomycin-C (8 mg/m 2) (cycles 1, 2, 4, 6), vinblastine (6 mg/m 2), and cisplatin (50 mg/m 2) all on day 1; and cisplatin (75 mg/m 2) and etoposide (100 mg/m 2) on day 1 and (100 mg/m 2) orally twice a day on days 2-3. Results: The response rate for 40 evaluable patients (MVP: n = 23; PE: n = 17) was 18% (95% confidence interval [CI]: 9-32%). The response rate to MVP was 13% (95% CI: 5-32%, one complete and two partial responses) and to PE 24% (10-47%, four partial responses). Disease stabilised in 43% (26-63%) and 47% (26-69%) of women treated with MVP and PE, respectively. After a median follow-up of 18 months, 37 women (MVP: n = 19; PE: n = 18) died from their disease. Median (range) progression-free survival and overall survival were 6 months (0.4-18.7) and 9.9 months (1.3-40.8), respectively. Median progression-free survival for the MVP and PE groups was 5.5 and 6.2 months (Log-rank, P = 0.82), and median overall survival was 10.2 and 9.4 months (Log-rank, P = 0.46), respectively. The main toxicity was myelosuppression. Grades 3-4 neutropenia was more common in women treated with PE than in women treated with MVP (74% vs 30%; P = 0.012), but the incidence of neutropenic sepsis, relative to the number of chemotherapy cycles, was low (7% overall). The toxicity-related hospitalisation rate was 1.2 admissions per six cycles of chemotherapy. No treatment-related deaths occurred. MVP and PE chemotherapy have modest activity and are safe in women with metastatic breast cancer. © 2005 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

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Purpose: Data from two randomized phase III trials were analyzed to evaluate prognostic factors and treatment selection in the first-line management of advanced non-small cell lung cancer patients with performance status (PS) 2. Patients and Methods: Patients randomized to combination chemotherapy (carboplatin and paclitaxel) in one trial and single-agent therapy (gemcitabine or vinorelbine) in the second were included in these analyses. Both studies had identical eligibility criteria and were conducted simultaneously. Comparison of efficacy and safety was performed between the two cohorts. A regression analysis identified prognostic factors and subgroups of patients that may benefit from combination or single-agent therapy. Results: Two hundred one patients were treated with combination and 190 with single-agent therapy. Objective responses were 37 and 15%, respectively. Median time to progression was 4.6 months in the combination arm and 3.5 months in the single-agent arm (p < 0.001). Median survival imes were 8.0 and 6.6 months, and 1-year survival rates were 31 and 26%, respectively. Albumin <3.5 g, extrathoracic metastases, lactate dehydrogenase ≥200 IU, and 2 comorbid conditions predicted outcome. Patients with 0-2 risk factors had similar outcomes independent of treatment, whereas patients with 3-4 factors had a nonsignificant improvement in median survival with combination chemotherapy. Conclusion: Our results show that PS2 non-small cell lung cancer patients are a heterogeneous group who have significantly different outcomes. Patients treated with first-line combination chemotherapy had a higher response and longer time to progression, whereas overall survival did not appear significantly different. A prognostic model may be helpful in selecting PS 2 patients for either treatment strategy. © 2009 by the International Association for the Study of Lung Cancer.

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New members on bone marrow registries worldwide are needed to allow sufficient diversity in the donor pool to meet patient needs. We used the theory of planned behaviour belief-basis and surveyed students who had not donated blood previously (i.e. non-donors) (N = 150) about the behavioural, normative, and control beliefs informing their intentions to join the Australian Bone Marrow Donor Registry. Key beliefs predicting non-donors’ intentions included: viewing bone marrow donation as an invasion of the body (β = −.35), normative support from parents (β = .40), anticipating pain/side effects from giving blood (β = −.27), and lack of knowledge about how to register (β  = −.30). Few non-donors endorsed these beliefs, suggesting they are ideal targets for change in strategies encouraging bone marrow donor registration.

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Due to the critical shortage and continued need of blood and organ donations (ODs), research exploring similarities and differences in the motivational determinants of these behaviors is needed. In a sample of 258 university students, we used a cross-sectional design to test the utility of an extended theory of planned behavior (TPB) including moral norm, self-identity and in-group altruism (family/close friends and ethnic group), to predict people’s blood and OD intentions. Overall, the extended TPB explained 77.0% and 74.6% of variance in blood and OD intentions, respectively. In regression analyses, common contributors to intentions across donation contexts were attitude, self-efficacy and self-identity. Normative influences varied with subjective norm as a significant predictor related to OD intentions but not blood donation intentions at the final step of regression analyses. Moral norm did not contribute significantly to blood or OD intentions. In-group altruism (family/close friends) was significantly related to OD intentions only in regressions. Future donation strategies should increase confidence to donate, foster a perception of self as the type of person who donates blood and/or organs, and address preferences to donate organs to in-group members only.

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Purpose: The development of liver metastases from breast cancer is associated with a very poor prognosis, estimated at 4 months median survival. Since treatment with many chemotherapeutic agents is relatively contraindicated, we assessed the safety, tolerability and potential efficacy of combination chemotherapy with vinorelbine and cisplatin (ViP). Method: Pilot study in 11 patients with histologically confirmed breast carcinoma, radiological evidence of liver metastases and serum bilirubin greater than 1.5 times the upper limit of normal. Patients received up to six cycles of cisplatin (75 mg/m 2) every 21 days and vinorelbine (20 mg/m 2) on days 1 and 8 of every 21-day cycle. Measurement of liver lesions was performed on CT scan every 8 weeks into treatment. Results: The most frequently reported adverse event was myelosuppression. Other adverse effects included nausea, vomiting and mild neurotoxicity. Two patients died after one treatment with ViP, one of whom suffered an intracerebral haemorrhage that was possibly treatment-related. Improvement in liver function tests was observed in 10 patients, and mean time to normalization of bilirubin levels was 36 days. Partial responses were documented radiologically in 7 out of 11 patients treated. Median overall survival from trial entry was 6.5 months (range 11-364 days), with one patient alive 13 months from trial entry. Conclusion: Normalization of liver function is possible with ViP treatment of metastatic breast cancer, offering the potential to prolong survival. Phase II clinical trials of this regimen in this patient group should include measurement of quality of life in order to assess risk versus benefit.

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Red Blood Cells (RBCs) exhibit different types of motions and different deformed shapes, when they move through capillaries. RBCs can travel through capillaries having smaller diameters than RBCs’ diameter, due to the capacity of high deformability of the viscoelastic RBC membrane. The motion and the steady state shape of the RBCs depend on many factors, such as the geometrical parameters of the microvessel through which blood flows, the RBC membrane bending stiffness and the flow velocity. In this study, the effect of the RBC’s membrane stiffness on the deformation of a single RBC in a stenosed capillary is comprehensively examined. Smoothed Particle Hydrodynamics (SPH) in combination with the two-dimensional spring network membrane model is used to investigate the motion and the deformation property of the RBC. The simulation results demonstrate that the membrane bending stiffness of the RBC has a significant impact on the RBCs’ deformability.

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Upward long-distance mobile silencing has been shown to be phloem mediated in several different solanaceous species. We show that the Arabidopsis (Arabidopsis thaliana) seedling grafting system and a counterpart inducible system generate upwardly spreading long-distance silencing that travels not in the phloem but by template-dependent reiterated short-distance cell-to-cell spread through the cells of the central stele. Examining the movement of the silencing front revealed a largely unrecognized zone of tissue, below the apical meristem, that is resistant to the silencing signal and that may provide a gating or protective barrier against small RNA signals. Using a range of auxin and actin transport inhibitors revealed that, in this zone, alteration of vesicular transport together with cytoskeleton dynamics prevented or retarded the spread of the silencing signal. This suggests that small RNAs are transported from cell to cell via plasmodesmata rather than diffusing from their source in the phloem.

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The Australian Bone Marrow Donor Registry (ABMDR) is a publicly funded company that is part of an international network that facilitates unrelated bone marrow transplantation. This role means that the ABMDR has access to a large biospecimen repository, therefore making it a highly valuable research resource. Recognising the potential value of these biospecimens for research purposes, the ABMDR is in the process of determining whether, and how, to share its biospecimens with other biobanks. While this would undoubtedly be of value to the scientific community, and ultimately to the wider community, it would also inevitably transform the role of an institution whose primary role is therapeutic, and would compromise the degree of control that a custodian has over donated material. This article describe the challenges confronting the ABMDR, and organisations like it, in balancing their duties to donors, patients, researchers and the general public. These problems have led inevitably to the use of "property" rights language in the discussion of these issues but notions of gift, ownership, trusteeship and transfer might also be considered.

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Current state of the art robot mapping and navigation systems produce impressive performance under a narrow range of robot platform, sensor and environmental conditions, in contrast to animals such as rats that produce “good enough” maps that enable them to function under an incredible range of situations. In this paper we present a rat-inspired featureless sensor-fusion system that assesses the usefulness of multiple sensor modalities based on their utility and coherence for place recognition, without knowledge as to the type of sensor. We demonstrate the system on a Pioneer robot in indoor and outdoor environments with abrupt lighting changes. Through dynamic weighting of the sensors, the system is able to perform correct place recognition and mapping where the static sensor weighting approach fails.

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Objectives To evaluate the feasibility, acceptability and effects of a Tai Chi and Qigong exercise programme in adults with elevated blood glucose. Design, Setting, and Participants A single group pre–post feasibility trial with 11 participants (3 male and 8 female; aged 42–65 years) with elevated blood glucose. Intervention Participants attended Tai Chi and Qigong exercise training for 1 to 1.5 h, 3 times per week for 12 weeks, and were encouraged to practise the exercises at home. Main Outcome Measures Indicators of metabolic syndrome (body mass index (BMI), waist circumference, blood pressure, fasting blood glucose, triglycerides, HDL-cholesterol); glucose control (HbA1c, fasting insulin and insulin resistance (HOMA)); health-related quality of life; stress and depressive symptoms. Results There was good adherence and high acceptability. There were significant improvements in four of the seven indicators of metabolic syndrome including BMI (mean difference −1.05, p<0.001), waist circumference (−2.80 cm, p<0.05), and systolic (−11.64 mm Hg, p<0.01) and diastolic blood pressure (−9.73 mm Hg, p<0.001), as well as in HbA1c (−0.32%, p<0.01), insulin resistance (−0.53, p<0.05), stress (−2.27, p<0.05), depressive symptoms (−3.60, p<0.05), and the SF-36 mental health summary score (5.13, p<0.05) and subscales for general health (19.00, p<0.01), mental health (10.55, p<0.01) and vitality (23.18, p<0.05). Conclusions The programme was feasible and acceptable and participants showed improvements in metabolic and psychological variables. A larger controlled trial is now needed to confirm these promising preliminary results.

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The representation of vampires in horror movies and television programmes has changed considerably over the last two decades. No longer is the vampire portrayed simply as a monster or representation of death. Now, the vampire on our screen such as True Blood’s Bill Compton, or Twilight’s Edward Cullen, passes as human, chooses to make morally sound decisions, becomes an upstanding assimilated citizen, works in the community, and aspires to be a husband to mortal women. The success of recent series such as The Twilight Saga (2009, 2010, 2011, 2012), The Vampire Diaries (2009 - ) and True Blood (2008 - ) has popularised the idea of vampires who cling to remnants of their humanity (or memories of what it means to be human) and attempt to live as human, which builds upon similar – albeit embryonic – themes which emerged from the vampire sub-genre in the 1990s. Within these narratives, representations of the other have shifted from the traditional idea of the monster, to alternative and surprising loci. As this chapter argues, humans themselves, and the concept of the human body, now represent, in many instances, both abject and other. The chapter begins by considering the nature of the abject and otherness in relation to representations of classical vampires and how they have traditionally embodied the other. This provides a backdrop against which to examine the characteristics of the contemporary mainstreaming vampire ‘monster’. An examination of the broad thematic and representational shifts from other to mainstream vampire demonstrates how mainstream monsters are increasingly assimilating into mortal lifestyles with trappings that many viewers may find appealing. The same shifts in theme and representation also reveal that humans are frequently cast as mundane and unappealing in contemporary vampire narratives.

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Aim/Background TRALI is hypothesised to develop via a two-event mechanism involving both the patieint's underlying morbidity and blood product factors. The storage of cellular products has been implicated in cases of non-antibody mediated TRALI, however the pathophysiological mechanisms are undefined. We investigated blood product storage-related modulation of inflmmatory cells and medicators involved in TRALI. Methods In an in vitro mode, fresh human whole blood was mixed with culture media (control) or LPS as a 1st event and "transfused" with 10% (v/v) pooled supernatant (SN) from Day 1 (d1, n=75) or Day 42 (D42, n=113) packed red blood cells (PRBCs) as a 2nd event. Following 6hrs, culture SN was used to assess the overall inflammatory response (cytometric bead array) and a duplicate assay containing protein transport inhibitor was used to assess neutrophil- and monocyte-specific inflmamatory responses using multi-colour flow cytometry. Panels: IL-6, IL-8, IL-10, IL-12, IL-1, TNF, MCP-1, IP-10, MIP-1. One-way ANOVA 95% CI. Results In the absence of LPS, exposure to D1 or D42 PRBC-SN reduced monocyte expression of IL-6, IL-8 and Il-10. D42 PRBC-SN also reduced monocyte IP-10, and the overall IL-8 production was increased. In the presence of LPS, D1-PRBC SN only modified overall IP-10 levels which were reduced. However, cf LPS alone, the combination of LPS and D42 PRBC-SN resulted in increased neutrophil and monocyte productionof IL-1 and IL-8 as well as reduced monocyte TNF production. Additionally, LPS and D42 PRBC-SN resulted in overall inflmmatory changes: elevated IL-8,

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This recent decision of the New South Wales Court of Appeal considers the scope of the parens patriae jurisdiction in cases where the jurisdiction is invoked for the protection of a Gillick competent minor. As outlined below, in certain circumstances the law recognises that mature minors are able to make their own decisions concerning medical treatment. However, there have been a number of Commonwealth decisions which have addressed the issue of whether mature minors are able to refuse medical procedures in circumstances where refusal will result in the minor dying. Ultimately, this case confirms that the minor does not necessarily have a right to make autonomous decisions; the minor’s right to exercise his or her autonomous decision only exists when such decision accords with what is deemed to be in his or her best interests.

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Prolonged intermittent-sprint exercise (i.e., team sports) induce disturbances in skeletal muscle structure and function that are associated with reduced contractile function, a cascade of inflammatory responses, perceptual soreness, and a delayed return to optimal physical performance. In this context, recovery from exercise-induced fatigue is traditionally treated from a peripheral viewpoint, with the regeneration of muscle physiology and other peripheral factors the target of recovery strategies. The direction of this research narrative on post-exercise recovery differs to the increasing emphasis on the complex interaction between both central and peripheral factors regulating exercise intensity during exercise performance. Given the role of the central nervous system (CNS) in motor-unit recruitment during exercise, it too may have an integral role in post-exercise recovery. Indeed, this hypothesis is indirectly supported by an apparent disconnect in time-course changes in physiological and biochemical markers resultant from exercise and the ensuing recovery of exercise performance. Equally, improvements in perceptual recovery, even withstanding the physiological state of recovery, may interact with both feed-forward/feed-back mechanisms to influence subsequent efforts. Considering the research interest afforded to recovery methodologies designed to hasten the return of homeostasis within the muscle, the limited focus on contributors to post-exercise recovery from CNS origins is somewhat surprising. Based on this context, the current review aims to outline the potential contributions of the brain to performance recovery after strenuous exercise.