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Stroke survivors' perspectives on recovering in rural and remote Australia: A systematic mixed studies review. Aust Occup Ther J 2021; 69:214-230. [PMID: 34918349 DOI: 10.1111/1440-1630.12779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 11/23/2021] [Accepted: 11/25/2021] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Stroke survivors recovering in rural and remote locations often have little or no access to rehabilitation services. The purpose of this study was to review the literature on recovering in rural and remote Australia, from the perspective of stroke survivors. Use of technology to support recovery was also explored. METHODS A systematic mixed studies review was conducted and reported according to the ENTREQ and PRISMA statements. MEDLINE (Ovid), CINAHL (EBSCOhost), Scopus, PsycINFO (ProQuest), Cochrane Library and Google Scholar were searched from inception to May 2021 for studies investigating stroke survivors' perspectives on recovering in rural or remote Australia. Qualitative, quantitative or mixed methods studies were included. Methodological quality was assessed using the Mixed Methods Appraisal Tool. Studies were not excluded or weighted according to methodological quality. To review the perspectives of stroke survivors on recovering, findings of included studies were mapped to the Living My Life framework and integrated using a convergent qualitative synthesis. The review protocol was registered on PROSPERO (CRD42017064990). RESULTS Eight studies met the inclusion criteria: six qualitative, one quantitative and one mixed methods. Methodological quality of the small number of studies ranged from low to high, indicating further high-quality research is needed. Included studies involved 152 stroke survivors in total. Review findings indicated that recovering was driven by working towards what mattered to stroke survivors, in ways that matched their beliefs and preferences and that worked for them in their world, including use of technology. CONCLUSION Stroke survivors recovering in rural and remote locations want to live their life by doing what matters to them, despite the challenges they face. They want support in ways that work for them in their environment. Further research is required to tailor support for stroke survivors that is specific to their life in rural and remote locations.
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Recovering is about living my life, as it evolves: perspectives of stroke survivors in remote northwest Queensland. Disabil Rehabil 2021; 44:3843-3852. [PMID: 33625948 DOI: 10.1080/09638288.2021.1890242] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
PURPOSE Recovering from stroke in remote Australia has rarely been considered, even though rehabilitation services are generally scarce. The primary purpose of this study was to explore stroke recovery, from the perspective of stroke survivors in remote northwest Queensland (NWQ), to explicate the lens through which they view recovering. The secondary purpose was to explore the role of technology to support stroke survivors in remote locations along their recovery journey. METHODS A qualitative study was undertaken using elements of constructivist grounded theory for data collection and analysis. Semi-structured interviews were conducted with fifteen stroke survivors and two partners living, working or travelling in remote NWQ. RESULTS From the participants' perspective, recovering in a remote area after stroke is about living my life, as it evolves by endeavouring to recover my way and navigating my recovery in my world. Technology was only considered helpful when it supported participants to recover their way in their world. CONCLUSION Recovering from stroke from the perspective of stroke survivors in remote NWQ is about living their life, as they want it to be, and as it unfolds within their own context. Technology only has a place when it can support them to recover their way in their world. These findings reinforce the importance of health professionals listening, learning about, and enabling stroke survivors along their recovery journey, within their remote context and support network.Implications for RehabilitationRecovering from the perspective of stroke survivors is about living their life as it evolves.To support stroke survivors from remote areas, health professionals need to listen to and learn from each stroke survivor about what matters to them, what works for them, and about their world; including the challenges (e.g., switching between services) and enablers (e.g., community support) as the stroke survivor perceives them.Finding ways to utilise the strengths within and around them, may improve the recovery process for the stroke survivor in a remote area, ensuring they can access care that meets their needs in their world.Working together with stroke survivors, health professionals need to consider how technology could help them to live their life, while recovering their way and in their world.
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Great Expectations: A Critical Review of and Suggestions for the Study of Reward Processing as a Cause and Predictor of Depression. Biol Psychiatry 2021; 89:134-143. [PMID: 32797941 PMCID: PMC10726343 DOI: 10.1016/j.biopsych.2020.06.012] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 05/20/2020] [Accepted: 06/10/2020] [Indexed: 10/24/2022]
Abstract
Both human and animal studies support the relationship between depression and reward processing abnormalities, giving rise to the expectation that neural signals of these processes may serve as biomarkers or mechanistic treatment targets. Given the great promise of this research line, we scrutinized those findings and the theoretical claims that underlie them. To achieve this, we applied the framework provided by classical work on causality as well as contemporary approaches to prediction. We identified a number of conceptual, practical, and analytical challenges to this line of research and used a preregistered meta-analysis to quantify the longitudinal associations between reward processing abnormalities and depression. We also investigated the impact of measurement error on reported data. We found that reward processing abnormalities do not reach levels that would be useful for clinical prediction, yet the available evidence does not preclude a possible causal role in depression.
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Prognostic Significance of Preoperative Neutrophil-Lymphocyte Ratio in Vascular Surgery: Systematic Review and Meta-Analysis. Vasc Endovascular Surg 2020; 54:697-706. [PMID: 32840176 DOI: 10.1177/1538574420951315] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
OBJECTIVE The global burden of surgical vascular disease is increasing and with it, the need for cost-effective, accessible prognostic biomarkers to aid optimization of peri-operative outcomes. The neutrophil-lymphocyte ratio (NLR) is emerging as a potential candidate biomarker for perioperative risk stratification. We therefore performed this systematic review and meta-analysis on the prognostic value of elevated preoperative NLR in vascular surgery. METHODS We searched Embase (Ovid), Medline (Ovid), and the Cochrane Library database from inception to June 2019. Screening was performed, and included all peer-reviewed original research studies reporting preoperative NLR in adult emergent and elective vascular surgical patients. Studies were assessed for bias and quality of evidence using a standardized tool. Meta-analysis was performed by general linear (mixed-effects) modelling where possible, and otherwise a narrative review was conducted. Between-study heterogeneity was estimated using the Chi-squared statistic and explored qualitatively. RESULTS Fourteen studies involving 5,652 patients were included. The overall methodological quality was good. Elevated preoperative NLR was associated with increased risk of long-term mortality (HR 1.40 [95%CI: 1.13-1.74], Chi-squared 60.3%, 7 studies, 3,637 people) and short-term mortality (OR: 3.08; 95%CI: 1.91-4.95), Chi-squared 66.59%, 4 studies, 945 people). Outcome measures used by fewer studies such as graft patency and amputation free survival were assessed via narrative review. CONCLUSIONS NLR is a promising, readily obtainable, prognostic biomarker for mortality outcomes following vascular surgery. Heterogeneity in patient factors, severity of vascular disease, and type of vascular surgery performed renders direct comparison of outcomes from the current literature challenging. This systematic review supports further investigation for NLR measurement in pre-vascular surgical risk stratification. In particular, the establishment of a universally accepted NLR cut-off value is of importance in real-world implementation of this biomarker.
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Tibial Density and Trabecular Microarchitecture in Army Recruit Stress Fracture Cases and Matched Uninjured Controls. Med Sci Sports Exerc 2017. [DOI: 10.1249/01.mss.0000517974.40993.a1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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An Exploration of the Metal Oxide-assisted Decomposition and Rearrangement of N-Acyl-1,3-oxazolidin-2-ones Leading to 2-Aryl-2-oxazolines [1]. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES 2014. [DOI: 10.1515/znb-2009-0909] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
An exploration into the utility of the thermally-induced (metal oxide-mediated) CO2 extrusion and subsequent rearrangement of N-acyl-1,3-oxazolidin-2-ones to form 2-aryl(alkyl)-2-oxazolines is described. The reaction is found to give moderate yields of the corresponding 2-oxazolines. Attempts to employ the above methodology to give enantiopure (R)- or (S)-2,5-diphenyl-2-oxazoline (the latter form being the natural product Oxytriphine) from enantiopure (and crystallographically characterised) (S)-N-benzoyl-5-phenyl-2-oxazolidinone led to the isolation of an essentially racemic product. These protocols are compared to other common methods used to form the oxazoline ring system and are placed into context with previous investigations of such ring forming reactions.
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Diabetes self-management education: miles to go. Nurs Res Pract 2013; 2013:581012. [PMID: 23577243 PMCID: PMC3616351 DOI: 10.1155/2013/581012] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Revised: 11/19/2012] [Accepted: 12/29/2012] [Indexed: 11/17/2022] Open
Abstract
This meta-analysis assessed how successfully Diabetes Self-Management Education (DSME) interventions help people with type 2 diabetes achieve and maintain healthy blood glucose levels. We included 52 DSME programs with 9,631 participants that reported post-intervention A1c levels in randomized controlled trials. The training conditions resulted in significant reductions in A1c levels compared to control conditions. However, the impact of intervention was modest shifting of only 7.23% more participants from diabetic to pre-diabetic or normal status, relative to the control condition. Most intervention participants did not achieve healthy A1c levels. Further, few DSME studies assessed long-term maintenance of A1c gains. Past trends suggest that gains are difficult to sustain over time. Our results suggested that interventions delivered by nurses were more successful than those delivered by non-nursing personnel. We suggest that DSME programs might do better by going beyond procedural interventions. Most DSME programs relied heavily on rules and procedures to guide decisions about diet, exercise, and weight loss. Future DSME may need to include cognitive self-monitoring, diagnosis, and planning skills to help patients detect anomalies, identify possible causes, generate corrective action, and avoid future barriers to maintaining healthy A1c levels. Finally, comprehensive descriptions of DSME programs would advance future efforts.
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Oxazoles XXII. The Cobalt(II) Coordination Chemistry of 2-(ortho-Anilinyl)-4,4-dimethyl-2-oxazoline: Syntheses, Properties, and Solid-State Structural Characterization. Aust J Chem 2010. [DOI: 10.1071/ch09259] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Ethanol solutions of the cobalt(ii) halides react with an excess of 2-(ortho-anilinyl)-4,4-dimethyl-2-oxazoline (1: i.e. 2-(2′-anilinyl)-4,4-dimethyl-4,5-dihydro-1,3-oxazole) to give isolable κ2-N,N′-bonded species of 1 in good to excellent yields. The complexes CoX2(1-κ2-N,N′)·(H2O) n have been isolated for X = Cl (2: n = 1/2), X = Br and I (3 and 4, respectively; n = 0); the solid-state structures (X-ray) are in accordance with those suggested by UV-visible spectroscopy and conductivity measurements (i.e. non-ionic complexes with a pseudo-tetrahedral coordination motif around Co). In contrast, reaction of excess 1 with Co(NCS)2 forms the octahedral (UV-visible, X-ray) bis-isothiocyanato complex Co(NCS-κ1-N′)2(1-κ2-N,N′)2 (5) with cis-oriented NCS groups and trans-disposed oxazolines. Calculations at the PM3(tm) level of theory suggest that this isomer is close in energy to the four other possible (gas-phase) isomers. Treatment of ethanol solutions of hydrated cobaltous nitrate with excess 1 yields a material analyzed as [Co(NO3)(1)(H2O)2](NO3) (6a) and a small amount (less than 1%) of a second complex (6b); the latter has been characterized (X-ray) as the hydrated octahedral complex [Co(NO3-κ1-O)(1-κ2-N,N′)2(OH2)](NO3). In this case, the nitrato and aqua groupings are located cis to one another and trans to the coordinated –NH2 groups. Complex 6a is surmised to have a [Co(NO3-κ2-O,O′)2(1-κ2-N,N′)(OH2)2]NO3 structure. Cobalt compounds 2–5 and 1 have also been screened for their antifungal properties against Aspergillus niger, Aspergillus flavus, Candida albicans, and Saccharomyces cerevisiae but were found to be inactive in this regard.
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Abstract
We previously showed that IgH sequence alone minimally influenced germinal centre (GC) B-cell survival fate. As end-stage effector B cells are typically more mutated than founder GC B cells, we worked to develop an assay that would enrich for populations of GC B cells with progressively increasing numbers of somatic mutations, which could potentially be used as an indicator of positive selection. We targeted CD45 as it has been shown to influence activation-induced cytidine deaminase (AID) expression. In this study, anti-CD77 and anti-CD45RO (RO) were used to subdivide CD19(+)IgD(-)CD38(+)CD77(+) centroblasts (CB) and CD19(+)IgD(-)CD38(+)CD77(-) centrocytes (CC) into three contiguous RO fractions (RO(-), RO(+/-) and RO(+)) and assessed whether mutation frequency and characteristics associated with selection varied with respect to increasing RO expression. Here, we show that the average number of mutations per IgV(H)4 transcript increased concordantly with RO for CC, but not for CB. CC also exhibited an RO-associated increase in replacement mutations. Comparative analysis of clonally related sequences revealed that increased mutations were not due to the exclusive persistence of surface RO on highly mutated cells. RO-expressing CC and CB pools showed increased signs of activation (CD69(+)) and were enriched for surface Ig(+) cells. BCR-crosslinking induced a significant increase in surface RO on total tonsillar and GC B cells, which collectively suggests that the RO-associated increase in mutations is attributable, at least in part, to the cycling of cells that may have recently undergone BCR-mediated selection, or are potentially in developmental transition between CC and CB stages.
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Structural criteria for the activity of rhodium(I) phosphine complexes in the catalytic dehydrocoupling of di-n-hexylsilane. Inorganica Chim Acta 2006. [DOI: 10.1016/j.ica.2005.12.045] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Oxazoline chemistry IX. Synthesis and characterisation of the first Zinc oxazoline dialkyldithiocarbamato complexes; X-ray crystal structure determinations of [Zn(S2CNR2-κ2S)2(2-R′-4,4-R″-2-oxazoline-κ1N)] (R=R′=Me, R″=H; R=Et, R′=Me, Et or Ph, R″=H; R=Bz; R′=R″=Me). Inorganica Chim Acta 2006. [DOI: 10.1016/j.ica.2005.06.074] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Monsieur Jules Verreaux and the platypus, Ornithorhynchus anatinus: comments on a naturaliste voyageur. AUSTRALIAN MAMMALOGY 2005. [DOI: 10.1071/am05147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
During his 15 month sojourn in Tasmania, Monsieur Jules Verreaux devoted most of his efforts
to studying the platypus, including making observations in the field. While some of his
observations were accurate and original, others were at odds with those of later naturalists and
current scientific findings. Like most other 19th century expatriate naturalists from the Northern
Hemisphere, Verreaux failed to determine that the species laid eggs but he described some
intriguing attributes which remain controversial and/or unsubstantiated by the work of more
recent naturalists and scientists. Perhaps the most controversial was that the newly emerged
young prod the mammary areas of the female and take the exuded milk from the surface of the
water. An annotated summary of Verreaux's findings is presented, along with the full text of his
work in French and a translation of this text into modern English.
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Oxazoline chemistry — Part IV: Synthesis and characterization of oxazoline complexes of the zinc halides. CAN J CHEM 2003. [DOI: 10.1139/v03-166] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The synthesis and characterization of 11 zinc halide derivatives that contain monodentate oxazoline ligands is described. The treatment of ether solutions of [ZnX2] (X = Cl, Br, I) with 2-aryl- or 2-methyl-2-oxazolines results in the formation of mildly hygroscopic complexes of the general formulae [ZnX2(ox)2] (ox = 2-methyl-2-oxazoline (1), 2,4,4-trimethyl-2-oxazoline (2), 2-phenyl-2-oxazoline (3), or 4,4-dimethyl-2-phenyl-2-oxazoline (4)), except in the case of ZnI2, which does not form an isolable complex — likely for steric reasons — with oxazoline 4. Treatment of [ZnBr2(4)2] with 1 reveals (1H NMR) that 1 only sluggishly displaces coordinated 4 at temperatures below 50 °C. The structural characterization, via single crystal X-ray diffraction, of six of the complexes, viz. [ZnI2(1)2], [ZnI2(2)2], [ZnX2(3)2] (X = Cl, Br, or I), and [ZnBr2(4)2], is also reported. All of these structurally characterized complexes are mononuclear zinc compounds with an overall distorted tetrahedral arrangement of the two halide and two oxazoline ligands around the zinc metal centre. The oxazoline series of complexes reported herein show little structural diversity, a facet which is in contrast to their substituted pyridine analogues.Key words: oxazoline, zinc, X-ray crystal structure, coordination complex, NMR spectroscopy, Zn(II).
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Drosophila rhino encodes a female-specific chromo-domain protein that affects chromosome structure and egg polarity. Genetics 2001; 159:1117-34. [PMID: 11729157 PMCID: PMC1461866 DOI: 10.1093/genetics/159.3.1117] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Here we describe our analyses of Rhino, a novel member of the Heterochromatin Protein 1(HP1) subfamily of chromo box proteins. rhino (rhi) is expressed only in females and chiefly in the germline, thus providing a new tool to dissect the role of chromo-domain proteins in development. Mutations in rhi disrupt eggshell and embryonic patterning and arrest nurse cell nuclei during a stage-specific reorganization of their polyploid chromosomes, a mitotic-like state called the "five-blob" stage. These visible alterations in chromosome structure do not affect polarity by altering transcription of key patterning genes. Expression levels of gurken (grk), oskar (osk), bicoid (bcd), and decapentaplegic (dpp) transcripts are normal, with a slight delay in the appearance of bcd and dpp mRNAs. Mislocalization of grk and osk transcripts, however, suggests a defect in the microtubule reorganization that occurs during the middle stages of oogenesis and determines axial polarity. This defect likely results from aberrant Grk/Egfr signaling at earlier stages, since rhi mutations delay synthesis of Grk protein in germaria and early egg chambers. In addition, Grk protein accumulates in large, actin-caged vesicles near the endoplasmic reticulum of stages 6-10 egg chambers. We propose two hypotheses to explain these results. First, Rhi may play dual roles in oogenesis, independently regulating chromosome compaction in nurse cells at the end of the unique endoreplication cycle 5 and repressing transcription of genes that inhibit Grk synthesis. Thus, loss-of-function mutations arrest nurse cell chromosome reorganization at the five-blob stage and delay production or processing of Grk protein, leading to axial patterning defects. Second, Rhi may regulate chromosome compaction in both nurse cells and oocyte. Loss-of-function mutations block nurse cell nuclear transitions at the five-blob stage and activate checkpoint controls in the oocyte that arrest Grk synthesis and/or inhibit cytoskeletal functions. These functions may involve direct binding of Rhi to chromosomes or may involve indirect effects on pathways controlling these processes.
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Local control of T3N0 glottic carcinoma by 60 Gy given over five weeks in 2.4 Gy daily fractions. One more point on the biological effective dose (BED) curve. Radiother Oncol 2001; 59:219-20. [PMID: 11325452 DOI: 10.1016/s0167-8140(01)00286-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Seventy patients with T3N0 glottic cancer who received a total dose of 60 Gy in twenty-five 2.4 Gy daily fractions over 5 weeks had an initial post radiation primary recurrence free rate of 65% at 5 years. This provides one more point for the dose response for T3 glottic cancer Radiother Oncol (1999) 15.
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Elevated serum and bronchoalveolar lavage fluid levels of interleukin 8 and granulocyte colony-stimulating factor associated with the acute chest syndrome in patients with sickle cell disease. Br J Haematol 2000; 111:482-90. [PMID: 11122088 DOI: 10.1046/j.1365-2141.2000.02358.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The role of cytokines in the development of acute chest syndrome (ACS) in patients with sickle cell disease (SCD) was studied. Serum interleukin 8 (IL-8) levels were elevated in 14 episodes and undetectable in six out of 20 episodes of ACS in 19 patients with SCD. In contrast, IL-8 levels were undetectable in the sera of 29 control patients with SCD studied during routine clinic visits or hospitalization for vaso-occlusive crises. The differences in mean IL-8 levels and the proportion of patients with detectable levels between the two groups were highly significant (P < 0.0001 and 0.04 respectively). The mean IL-8 level in bronchial fluid samples from children with ACS was also significantly higher than that in sickle cell patients undergoing elective surgery (5500 +/- 1400 pg/ml vs. 1900 +/- 470 pg/ml, P = 0.03). Granulocyte colony-stimulating factor (G-CSF) (2000 +/- 1700 pg/ml) was present in five out of six samples of bronchial fluid, but not serum, from children with ACS. All but one of the patients with ACS studied were negative for the Duffy red cell antigen, which is a receptor that binds and inactivates IL-8 and other chemokines. These findings suggest that IL-8 and G-CSF may play a role in the development of the ACS and the complications associated with it.
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Significance of axillary lymph node extranodal soft tissue extension and indications for postmastectomy irradiation. Cancer 2000; 89:223-5. [PMID: 10897026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
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Bone marrow transplantation versus periodic prophylactic blood transfusion in sickle cell patients at high risk of ischemic stroke: a decision analysis. Blood 2000; 95:3057-64. [PMID: 10807769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
Measurement of cerebral blood velocity (CBV) by transcranial Doppler has been used to identify patients with sickle cell disease (SCD) who are at high risk of ischemic stroke. This study examines outcomes of bone marrow transplantation (BMT) and periodic blood transfusion (PBT) as a basis for making treatment recommendations for patients who have elevated CBV and no other indications for BMT. Decision analysis was used to compare the number of quality-adjusted life years (QALYs) experienced by a population of patients with SCD at high risk for stroke who were treated with PBT or BMT. Markov models were constructed to represent the clinical course of patients with SCD who were treated with PBT or BMT. Medical literature and expert opinion provided risks of stroke and death for different disease states, estimates of transition probabilities from one clinical state to another, and quality of life. An intention-to-treat analysis and an analysis of treatment received were both performed on hypothetical cohorts of 100 000 patients. Patients with SCD who were managed with a strategy of intending to provide BMT could expect 16.0 QALYs, compared with 15.7 QALYs for a strategy of intending to provide PBT; however, the variation around these estimates was large. In the treatment received analysis, patients compliant with PBT therapy and iron chelation could expect the best outcomes (19.2 QALYs). From a policy perspective, neither BMT nor PBT can be considered the "best" treatment for children with SCD who have abnormal CBV. Abnormal CBV should not be the only criterion for selecting patients with sickle cell for BMT.
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Doxazosin inhibits retinoblastoma protein phosphorylation and G(1)-->S transition in human coronary smooth muscle cells. Arterioscler Thromb Vasc Biol 2000; 20:1216-24. [PMID: 10807736 DOI: 10.1161/01.atv.20.5.1216] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Previous studies have demonstrated that the alpha(1)-adrenergic receptor antagonist doxazosin (Dox) inhibits multiple mitogenic signaling pathways in human vascular smooth muscle cells. This broad antiproliferative activity of Dox occurs through a novel mechanism unrelated to its blocking the alpha(1)-adrenergic receptor. Flow cytometry demonstrated that Dox prevents mitogen-induced G(1)-->S progression of human coronary artery smooth muscle cells (CASMCs) in a dose-dependent manner, with a maximal reduction of S-phase transition by 88+/-10.5% in 20 ng/mL platelet-derived growth factor and 1 micromol/L insulin (P+I)-stimulated cells (P<0.01 for 10 micromol/L Dox versus P+I alone) and 52+/-18.7% for 10% FBS-induced mitogenesis (P<0.05 for 10 micromol/L Dox versus 10% FBS alone). Inhibition of G(1) exit by Dox was accompanied by a significant blockade of retinoblastoma protein (Rb) phosphorylation. Hypophosphorylated Rb sequesters the E2F transcription factor, leading to G(1) arrest. Adenoviral overexpression of E2F-1 stimulated quiescent CASMCs to progress through G(1) and enter the S phase. E2F-mediated G(1) exit was not affected by Dox, suggesting that it targets events upstream from Rb hyperphosphorylation. Downregulation of the cyclin-dependent kinase inhibitory protein p27 is important for maximal activation of G(1) cyclin/cyclin-dependent kinase holoenzymes to overcome the cell cycle inhibitory activity of Rb. In Western blot analysis, p27 levels decreased after mitogenic stimulation (after P+I, 43+/-1.8% of quiescent cells [P<0.01 versus quiescent cells]; after 10% FBS, 55+/-7.7% of quiescent cells [P<0. 05 versus quiescent cells]), whereas the addition of Dox (10 micromol/L) markedly attenuated its downregulation (after P+I, 90+/-8.3% of quiescent cells [P<0.05 versus P+I alone]; after 10% FBS, 78+/-8.3% of quiescent cells [P<0.05 versus 10% FBS alone]). Furthermore, Dox inhibited cyclin A expression, an E2F regulated gene that is essential for cell cycle progression into the S phase. The present study demonstrates that Dox inhibits CASMC proliferation by blocking cell cycle progression from the G(0)/G(1) phase to the S phase. This G(1)-->S blockade likely results from an inhibition of mitogen-induced Rb hyperphosphorylation through prevention of p27 downregulation.
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Peroxisome proliferator-activated receptor activators modulate the osteoblastic maturation of MC3T3-E1 preosteoblasts. FEBS Lett 2000; 471:119-24. [PMID: 10760525 DOI: 10.1016/s0014-5793(00)01372-7] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
The reduced bone mineral density (BMD) observed in osteoporosis results, in part, from reduced activity of bone-forming osteoblasts. We examined the effect of peroxisome proliferator-activated receptor (PPAR) activators on MC3T3-E1 preosteoblast maturation. Activators of PPARalpha, delta and gamma induced alkaline phosphatase activity, matrix calcification and the expression of osteoblast genes as determined by reverse transcriptase-polymerase chain reaction. However, at relatively high concentrations of the specific PPARgamma ligands, ciglitazone and troglitazone, maturation was inhibited. PPARalpha, delta and gamma1 were expressed in MC3T3-E1 cells. PPARgamma1 mRNA and protein levels were induced early during osteoblastic maturation. We speculate that endogenous and pharmacological PPAR activators may affect BMD by modulating osteoblastic maturation.
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Effect of time interval between breast-conserving surgery and radiation therapy on ipsilateral breast recurrence. Int J Radiat Oncol Biol Phys 2000; 46:363-72. [PMID: 10661343 DOI: 10.1016/s0360-3016(99)00412-5] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
PURPOSE To examine the effect of the time interval (interval) between breast-conserving surgery (BCS) and the start of radiation therapy (RT) on the subsequent risk of ipsilateral breast cancer recurrence (IBR). METHODS AND MATERIALS We reviewed interval and a number of prognostic and treatment factors among 1,962 women treated with BCS and RT for invasive breast cancer diagnosed between January 1, 1989 and December 31, 1993 in British Columbia, Canada. Subjects were female, less than 90 years old at diagnosis, not treated with chemotherapy, not stage T4 or M1, and had survived more than 30 days from diagnosis. The cumulative incidence of IBR was estimated in four interval groups: 0-5, 6-8, 9-12, and 13+ weeks. Only 23 women had an interval of greater than 20 weeks between BCS and start of RT. To assess whether an imbalance of prognostic and treatment factors could be obscuring real differences between the interval groups, Cox proportional hazards regression analyses were conducted. RESULTS Median follow-up was 71 months. The crude incidence of IBR for the entire sample was 3.9%. The cumulative incidence of IBR in the 6-8, 9-12, and 13+ week groups was not statistically significantly different from the cumulative incidence of IBR in the 0-5 week group. Multivariate analyses demonstrated that patients not using tamoxifen p = 0.027) and those with grade 3 histology (p = 0.003) were more likely to recur in the breast. Interval between BCS and RT was not a statistically significant predictor of breast recurrence when entered into a model incorporating tamoxifen use and tumor grade (0-5 vs. 6-8 weeks, p = 0.872; 0-5 vs. 9-12 weeks, p = 0.665; 0-5 vs. 13+ weeks, p = 0.573). CONCLUSIONS We found no univariate or multivariate difference in ipsilateral breast cancer recurrence between intervals of 0 to 20 weeks from breast conserving surgery to start of radiation therapy, in a population-based, low risk group of women not receiving adjuvant chemotherapy, after controlling for other factors important in predicting ipsilateral breast cancer recurrence.
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Abstract
The comet assay is a single-cell gel electrophoresis technique that measures DNA damage in individual cells. Since radiation produces 3-4 times more DNA damage in well-oxygenated cells compared with hypoxic cells, this assay can quantify the fraction of radiation-resistant hypoxic cells found in many solid tumours. This paper summarizes our results with 73 accessible metastatic tumours irradiated with palliative intent. Hypoxic fractions ranged from 0.0 to 0.67 with a mean of 0.15; 62% of these advanced tumours showed a hypoxic fraction > 0.05. Comparisons between two sequential aspirates in 33 tumours gave a slope of 0.92 (r2 = 0.88), suggesting that a single aspirate is generally representative of the tumour. A limitation, however, is that the hypoxic fraction could not be measured in clinical samples given a conventional dose of 2 Gy.
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Atherogenic diet and minimally oxidized low density lipoprotein inhibit osteogenic and promote adipogenic differentiation of marrow stromal cells. J Bone Miner Res 1999; 14:2067-78. [PMID: 10620066 DOI: 10.1359/jbmr.1999.14.12.2067] [Citation(s) in RCA: 189] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In osteoporosis, the bone marrow stroma osteogenic cell population declines and adipocyte numbers increase. We recently showed that oxidized lipids inhibit differentiation of preosteoblasts. In this report, we assess the effect of minimally oxidized low density lipoprotein (MM-LDL) on osteoblastic differentiation of murine marrow stromal cells, M2-10B4. MM-LDL, but not native LDL, inhibited stromal cell osteoblastic differentiation as demonstrated by inhibition of alkaline phosphatase activity, collagen I processing, and mineralization, through a mitogen-activated protein kinase-dependent pathway. In addition, marrow stromal cells from C57BL/6 mice fed a high fat, atherogenic diet failed to undergo osteogenic differentiation in vitro. The ability of MM-LDL to regulate adipogenesis was also assessed. Treatment of M2-10B4 as well as 3T3-L1 preadipocytes with MM-LDL, but not native LDL, promoted adipogenic differentiation in the presence of peroxisome proliferator-activated receptor (PPAR) gamma agonist thiazolidinediones, BRL49653 and ciglitizone. Based on promoter-reporter construct experiments, MM-LDL may be acting in part through activating PPARalpha. These observations suggest that LDL oxidation products promote osteoporotic loss of bone by directing progenitor marrow stromal cells to undergo adipogenic instead of osteogenic differentiation. These data lend support to the "lipid hypothesis of osteoporosis."
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Soma-to-germline interactions during Drosophila oogenesis are influenced by dose-sensitive interactions between cut and the genes cappuccino, ovarian tumor and agnostic. Genetics 1999; 153:289-303. [PMID: 10471713 PMCID: PMC1460760 DOI: 10.1093/genetics/153.1.289] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The cut gene of Drosophila melanogaster encodes a homeodomain protein that regulates a soma-to-germline signaling pathway required for proper morphology of germline cells during oogenesis. cut is required solely in somatic follicle cells, and when cut function is disrupted, membranes separating adjacent nurse cells break down and the structural integrity of the actin cytoskeleton is compromised. To understand the mechanism by which cut expression influences germline cell morphology, we determined whether binucleate cells form by defective cytokinesis or by fusion of adjacent cells. Egg chambers produced by cut, cappuccino, and chickadee mutants contained binucleate cells in which ring canal remnants stained with antibodies against Hu-li tai shao and Kelch, two proteins that are added to ring canals after cytokinesis is complete. In addition, defects in egg chamber morphology were observed only in middle to late stages of oogenesis, suggesting that germline cell cytokineses were normal in these mutants. cut exhibited dose-sensitive genetic interactions with cappuccino but not with chickadee or other genes that regulate cytoskeletal function, including armadillo, spaghetti squash, quail, spire, Src64B, and Tec29A. Genomic regions containing genes that cooperate with cut were identified by performing a second-site noncomplementing screen using a collection of chromosomal deficiencies. Sixteen regions that interact with cut during oogenesis and eight regions that interact during the development of other tissues were identified. Genetic interactions between cut and the ovarian tumor gene were identified as a result of the screen. In addition, the gene agnostic was found to be required during oogenesis, and genetic interactions between cut and agnostic were revealed. These results demonstrate that a signaling pathway regulating the morphology of germline cells is sensitive to genetic doses of cut and the genes cappuccino, ovarian tumor, and agnostic. Since these genes regulate cytoskeletal function and cAMP metabolism, the cut-mediated pathway functionally links these elements to preserve the cytoarchitecture of the germline cells.
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Peroxisome proliferator-activated receptor activators target human endothelial cells to inhibit leukocyte-endothelial cell interaction. Arterioscler Thromb Vasc Biol 1999; 19:2094-104. [PMID: 10479650 DOI: 10.1161/01.atv.19.9.2094] [Citation(s) in RCA: 279] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
An early event in acute and chronic inflammation and associated diseases such as atherosclerosis and rheumatoid arthritis is the induced expression of specific adhesion molecules on the surface of endothelial cells (ECs), which subsequently bind leukocytes. Peroxisome proliferator-activated receptors (PPARs), members of the nuclear receptor superfamily of transcription factors, are activated by fatty acid metabolites, peroxisome proliferators, and thiazolidinediones and are now recognized as important mediators in the inflammatory response. Whether PPAR activators influence the inflammatory responses of ECs is unknown. We show that the PPAR activators 15-deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)), Wyeth 14643, ciglitazone, and troglitazone, but not BRL 49653, partially inhibit the induced expression of vascular cell adhesion molecule-1 (VCAM-1), as measured by ELISA, and monocyte binding to human aortic endothelial cells (HAECs) activated by phorbol 12-myristate 13-acetate (PMA) or lipopolysaccharide. The "natural" PPAR activator 15d-PGJ(2) had the greatest potency and was the only tested molecule capable of partially inhibiting the induced expression of E-selectin and neutrophil-like HL60 cell binding to PMA-activated HAECs. Intracellular adhesion molecule-1 induction by PMA was unaffected by any of the molecules tested. Both PPAR-alpha and PPAR-gamma mRNAs were detected in HAECs by using reverse transcription-polymerase chain reaction and a ribonuclease protection assay; however, we have yet to determine which, if any, of the PPARs are mediating this process. These results suggest that certain PPAR activators may help limit chronic inflammation mediated by VCAM-1 and monocytes without affecting acute inflammation mediated by E-selectin and neutrophil binding.
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The use of static mass spectrometry to determine the combined stable isotopic composition of small samples of atmospheric methane. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 1999; 13:1329-1333. [PMID: 10407320 DOI: 10.1002/(sici)1097-0231(19990715)13:13<1329::aid-rcm648>3.0.co;2-p] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Global budgets of atmospheric trace gases are increasingly being constrained by means of stable isotope measurements. Published analytical techniques for studying the parallel stable isotopic composition of methane (delta(13)C and deltaD) require prohibitively large quantities of methane for analysis, making them unsuitable for studies where sample size is small, e.g. soil methane fluxes. A highly sensitive static mass spectrometer has been developed which uniquely uses CH(4) as the analyte. The method requires only 8 ng of CH(4) for analysis (<10 mL ambient air), making replicated measurements of the isotopic composition of CH(4) in small samples feasible for the first time. This paper provides the first detailed description of the instrumentation and the analytical technique. The technique has been used to analyse small samples of air collected in Snowdonia over 21 months. The combined stable isotopic composition (delta(17)M) ranged from 29.5 to 35.5 per thousand, with an average value of 32.2 per thousand, and was strongly correlated with wind direction (p <0.01, r(2) = 0.71). Copyright 1999 John Wiley & Sons, Ltd.
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Compliance with radiation treatment guidelines in a provincial setting. CANCER PREVENTION & CONTROL : CPC = PREVENTION & CONTROLE EN CANCEROLOGIE : PCC 1999; 3:196-201. [PMID: 10474767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Since 1979, consensus guidelines have been produced for radiation treatment practice in British Columbia. These guidelines have been revised, updated and circulated to all radiation oncologists periodically. A comprehensive computer database for all patients receiving radiation treatment in the province was established in 1984. Between 1985 and 1996 inclusive, 7667 prostate cancer patients and 9748 breast cancer patients received primary radical radiation treatment or adjuvant postsurgical treatment. Palliative treatments and the treatment of other disease sites are not included in this review. Compliance of these treatments with the published guidelines is reported. Over 98% of patients completed treatment as planned and, in the last 3 years, more than 90% of patients received a guideline dose to either the prostate or the breast. Compliance was less in the treatment of the regional lymph nodes in breast cancer. Practice in prostate cancer tended to precede the changes in the guidelines. This was not the case for breast cancer.
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Abstract
BACKGROUND AND PURPOSE The use of ipsilateral irradiation techniques to treat patients with carcinoma of the tonsil reduces the acute radiation reaction in the contralateral pharynx and late damage to the contralateral salivary tissue. However, this may also spare microscopic disease in apparently uninvolved contralateral lymph nodes. The purpose of this study was to analyse the survival and recurrence rates and sites of recurrance in a group of patients with carcinoma of the tonsil treated with ipsilateral techniques. MATERIALS AND METHODS Between 1975 and 1993, 271 patients with invasive squamous cell cancer of the tonsil were referred to the Vancouver Cancer Centre (VCC). One hundred and seventy-eight received ipsilateral radiation treatment. Three received surgery only, six post-operative radiation, 12 supportive treatment only and 72 bilateral radiation treatment. In the absence of bilateral neck nodes and extensive lymphodenopathy, field sizes were generally kept small to include the primary tumour and the first echelon of nodes. The most common dose was 60 Gy in 25 daily fractions in 5 weeks (2.4 Gy per day). RESULTS AND DISCUSSION The disease specific survival for all patients treated by radical radiation treatment was 61% at 5 years. For the 178 patients who received ipsilateral radiation treatment the overall primary tumour control rate by ipsilateral radiation treatment alone was 75% and for T1 and T2 tumours 84%. Eight (7.5%) of 101 of these patients with N0 nodes at presentation and without prior failure at the primary site, developed nodal recurrence (four within the initially radiated high dose volume). Two developed contralateral nodes, and two developed field edge nodal recurrence, one cured by surgery. In 54 patients with N1 disease, five developed nodal recurrence, two within field, two contralateral, one of whom was cured by surgery, and one at field edge. In 23 patients with N2a, N2b or N3 disease node control was achieved from radiation treatment in 11 and two more were cured by surgery. All nodal failures were within the radiated volume. Overall, 10 of the 25 patients with nodal failure were cured by subsequent surgery. CONCLUSIONS Ipsilateral treatment of patients with carcinoma of the tonsil gives survival results that are at least as good as those reported with bilateral treatment with fewer side effects and a very low risk of failure in the contralateral neck.
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An automated image cytometry system for monitoring DNA ploidy and other cell features of radiotherapy and chemotherapy patients. RADIATION MEDICINE 1999; 17:47-57. [PMID: 10378652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
DNA content and distribution in cell nuclei were studied in samples of fine-needle aspiration (FNA) from 27 locally advanced breast and head and neck cancers in two going randomized trials that compared accelerated fractionation to standard fractionation radiation in locally advanced breast cancer and head and neck cancer. Two image cytometry methods were compared: a new, fully automated DNA image cytometry system (AIC) and a conventional image cytometry (CIC) system with manual selection, focusing, and segmentation of cells. The results of both techniques were compared on the basis of DNA histogram parameters including DNA index (DI), mean DNA values (MDV), and Auer's DNA histogram patterns. An excellent correlation was achieved between the two imaging techniques in terms of DI (r=0.985, p<0.001) and MDV (r=0.951, p<0.001) as well as between Auer's histogram patterns, where both methods agreed completely. It was concluded in these analyses that the two image cytometry methods were equivalent. However, the AIC offered an advantage by scanning samples in a fully automated way, which represented significant time saving for cytopathologists working with the system, as well as a larger number of cells used in the automated analysis. With the automated image cytometer, 500 relevant cells were collected and analyzed in about 10 minutes, where with the interactive (manual) method, it took typically an hour to collect and analyze only about 250 cells. Seventeen samples were sufficient for flow analysis. Image cytometry and flow cytometry showed good agreement in DI determination; however, three cases reported as diploid by flow cytometry were found to be aneuploid by image cytometry techniques.
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Synergistic activation of transcription by nuclear factor Y and sterol regulatory element binding protein. J Lipid Res 1998; 39:767-76. [PMID: 9555942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The current studies define the role of three distinct cis-elements in the proximal promoter of the rat farnesyl diphosphate (FPP) synthase gene. The three cis-elements, a sterol regulatory element 3 (SRE-3) flanked by an ATTGG motif (inverted CCAAT box), and a CCAAT box, form a sterol regulatory unit that is necessary and sufficient for sterol-regulated expression of FPP synthase promoter-reporter genes. FPP synthase promoter-reporter genes, that contain promoters with either wild-type nucleotide sequences or mutations in one or more of the three cis-elements, were transiently transfected into CV-1 cells. The activity of the wild-type promoter-reporter gene increased when the cells were incubated in sterol-depleted media or when the cells were co-transfected with a plasmid encoding the mature form of SRE binding protein (SREBP-1a). The results with the mutant promoter-reporter genes demonstrated that all three cis-elements were necessary for normal expression/regulation of the reporter gene by either sterols or by co-expressed SREBP-1a. Gel mobility shift assays demonstrated that the synergistic binding of SREBP-1a to SRE-3 was dependent on the binding of recombinant nuclear factor Y (NF-Y) to the DNA, consistent with the in vivo regulation studies.
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An analysis of structural similarity in the iron and manganese superoxide dismutases based on known structures and sequences. Biometals 1998; 11:159-73. [PMID: 9542069 DOI: 10.1023/a:1009238214394] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
There are two types of homologous enzymes catalysing the dismutation of the superoxide radical--Cu-Zn superoxide dismutases, and manganese or iron superoxide dismutases. In the latter two forms there is a high percentage of identity in the primary structures, and the tertiary structures are very similar particularly in the areas of the active site and in the residues responsible for the formation of the dimer. The quaternary structure of the dimer is also highly conserved. However, it has been found that despite this conservation there is strong metal ion specificity and many enzymes in the family will only be active if the correct metal ion is present. The purpose of this study has been to analyse solved X-ray structures for interactions common in both the manganese and iron forms and those that are specific to each, which may indicate reasons for the metal ion specificity. Initial analysis points to the probability that it is a combination of a number of residues, and not necessarily the same ones in every instance, which confer the specificity. In addition we have identified some anomalies in the currently available Fe/MnSOD structures which may require further remodelling and refinement.
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cAMP stimulates osteoblast-like differentiation of calcifying vascular cells. Potential signaling pathway for vascular calcification. J Biol Chem 1998; 273:7547-53. [PMID: 9516456 DOI: 10.1074/jbc.273.13.7547] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The role of the cAMP signaling pathway in vascular calcification was investigated using calcifying vascular cells (CVC) derived from primary aortic medial cell cultures. We previously showed that CVC have fibroblastic morphology and express several osteoblastic differentiation markers. After confluency, they aggregate into cellular condensations, which later mature into nodules where mineralization is localized. Here, we investigated the effects of cAMP on CVC differentiation because it plays a role in both osteoblastic differentiation and vascular disease. Dibutyryl-cAMP or forskolin treatment of CVC for 3 days induced osteoblast-like "cuboidal" morphology, inhibited proliferation, and enhanced alkaline phosphatase activity, all early markers of osteoblastic differentiation. Isobutylmethylxanthine and cholera toxin had the same effects. Treatment of CVC with pertussis toxin, however, did not induce the morphological change or increase alkaline phosphatase activity, although it inhibited CVC proliferation to a similar extent. cAMP also increased type I procollagen production and gene expression of matrix gamma-carboxyglutamic acid protein, recently shown to play a role in in vivo vascular calcification. cAMP inhibited the expression of osteopontin but did not affect the expression of osteocalcin and core binding factor. Prolonged cAMP treatment enhanced matrix calcium-mineral incorporation but inhibited the condensations resulting in diffuse mineralization throughout the monolayer of cells. Treatment of CVC with a protein kinase A-specific inhibitor, KT5720, inhibited alkaline phosphatase activity and mineralization during spontaneous CVC differentiation. These results suggest that the cAMP pathway promotes in vitro vascular calcification by enhancing osteoblast-like differentiation of CVC.
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A randomised trial of accelerated versus conventional radiotherapy in head and neck cancer. Cancer Radiother 1998. [DOI: 10.1016/s1278-3218(98)89072-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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dally, a Drosophila glypican, controls cellular responses to the TGF-beta-related morphogen, Dpp. Development 1997; 124:4113-20. [PMID: 9374407 DOI: 10.1242/dev.124.20.4113] [Citation(s) in RCA: 173] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Decapentaplegic (Dpp) is a Drosophila member of the Transforming Growth Factor-beta (TGF-beta)/Bone Morphogenetic Protein (BMP) superfamily of growth factors. Dpp serves as a classical morphogen, where concentration gradients of this secreted factor control patterning over many cell dimensions. Regulating the level of Dpp signaling is therefore critical to its function during development. One type of molecule proposed to modulate growth factor signaling at the cell surface are integral membrane proteoglycans. We show here that division abnormally delayed (dally), a Drosophila member of the glypican family of integral membrane proteoglycans is required for normal Dpp signaling during development, affecting cellular responses to this morphogen. Ectopic expression of dally+ can alter the patterning activity of Dpp, suggesting a role for dally+ in modulating Dpp signaling strength. These findings support a role for members of the glypican family in controlling TGF-beta/BMP activity in vivo by affecting signaling at the cell surface.
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Abstract
BACKGROUND Radiotherapy after mastectomy to treat early breast cancer has been known since the 1940s to reduce rates of local relapse. However, the routine use of postoperative radiotherapy began to decline in the 1980s because it failed to improve overall survival. We prospectively tested the efficacy of combining radiotherapy with chemotherapy. METHODS From 1978 through 1986, 318 premenopausal women with node-positive breast cancer were randomly assigned, after modified radical mastectomy, to receive chemotherapy plus radiotherapy or chemotherapy alone. Radiotherapy was given to the chest wall and locoregional lymph nodes between the fourth and fifth cycles of cyclophosphamide, methotrexate, and fluorouracil. RESULTS After 15 years of follow-up, the women assigned to chemotherapy plus radiotherapy had a 33 percent reduction in the rate of recurrence (relative risk, 0.67; 95 percent confidence interval, 0.50 to 0.90) and a 29 percent reduction in mortality from breast cancer (relative risk, 0.71; 95 percent confidence interval, 0.51 to 0.99), as compared with the women treated with chemotherapy alone. CONCLUSIONS Radiotherapy combined with chemotherapy after modified radical mastectomy decreases rates of locoregional and systemic relapse and reduces mortality from breast cancer.
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cut interacts with Notch and protein kinase A to regulate egg chamber formation and to maintain germline cyst integrity during Drosophila oogenesis. Development 1997; 124:3663-72. [PMID: 9342058 DOI: 10.1242/dev.124.18.3663] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Communications between the germline and the soma during Drosophila oogenesis have been previously shown to be essential for the formation of egg chambers and to establish polarity in the developing oocyte. In this report, we demonstrate that the function of a somatically expressed gene, cut, is critical for maintaining the structural integrity of germline-derived cells and their arrangement within an egg chamber. Genetic manipulations of cut activity resulted in defective packaging of germline-derived cysts into egg chambers and disintegration of the structural organization of oocyte-nurse cell complexes to generate multinucleate germline-derived cells. We also found that cut interacts genetically with the Notch gene and with the catalytic subunit of Protein kinase A gene during egg chamber morphogenesis. Since cut expression is restricted to the somatic follicle cells and cut mutant germline clones are phenotypically normal, we propose that the defects in the assembly of egg chambers and the changes in germline cell morphology observed in cut mutant egg chambers are the result of altered interactions between follicle cells and germline cells. cut encodes a nuclear protein containing DNA-binding motifs, and we suggest that it participates in intercellular communications by regulating the expression of molecules that directly participate in this process.
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Abstract
BACKGROUND AND PURPOSE To study the effect of accelerated radiation treatment in locally advanced head and neck cancer, a prospective randomised trial was conducted comparing two fractionation schemes which differed only in the overall treatment time; fraction size and total dose were the same in both arms. MATERIALS AND METHODS Eighty-two patients with stage 3 or 4 squamous cell cancer of the oral cavity, oropharynx, hypopharynx or larynx considered suitable for radical radiotherapy as primary treatment were stratified by site and stage and randomised to receive 66 Gy in 33 2 Gy daily fractions in 45-48 days (o.d.) or 66 Gy in 33 2 Gy twice daily fractions in 22-25 days (b.i.d.). RESULTS An initial improved clinical response in tumour control in the b.i.d. arm was not sustained and the 3 year recurrence free survival and overall survival rates were similar and not significantly different. The actuarial recurrence free survival was 49.1% in the b.i.d. arm and 44.3% in the o.d. arm. The disease free 3 year survival was 59.4% and 56.8%, respectively. The acute and late normal tissue effects were scored using the RTOG scale. As expected the acute effects were much greater in the b.i.d. arm. The combined grade 3 and 4 late effects were similar but the proportion of grade 4 reactions was significantly higher in the b.i.d. arm. The increase in grade 4 toxicity caused the trial to be discontinued after 82 of the planned 226 patients had been randomised. CONCLUSIONS The severity of the normal tissue effects and a failure to demonstrate sustained local control does not support this fractionation scheme in patients with such extensive head and neck cancer.
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Identification of glycerol-3-phosphate acyltransferase as an adipocyte determination and differentiation factor 1- and sterol regulatory element-binding protein-responsive gene. J Biol Chem 1997; 272:7298-305. [PMID: 9054427 DOI: 10.1074/jbc.272.11.7298] [Citation(s) in RCA: 203] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
We demonstrate that the mRNA levels of glycerol-3-phosphate acyltransferase (GPAT), a mitochondrial enzyme catalyzing the initial step in glycerolipid synthesis, are induced during the differentiation of 3T3-L1 preadipocytes to adipocytes and following ectopic expression of rat adipocyte determination and differentiation factor 1 (ADD1), a protein with high homology to the human sterol regulatory element-binding protein-1 (SREBP-1). The increase in GPAT mRNA levels that occurs during differentiation is partially prevented by ectopic expression of a dominant negative form of ADD1. Nucleotide sequences corresponding to the proximal promoter of the murine mitochondrial GPAT gene (Jerkins, A. A., Liu, W. R., Lee, S., and Sul, H. S. (1995) J. Biol. Chem. 270, 1416-1421) bound SREBP-1a and NF-Y in electromobility shift assays. In addition, GPAT promoter-luciferase reporter genes were stimulated by co-expression of SREBP-1a. This increase was attenuated when either a dominant negative form of NF-Y was co-transfected into the cells or when the GPAT promoter contained mutations in the putative binding sites for SREBP-1a or NF-Y. These studies demonstrate that the regulated expression of the mitochondrial GPAT gene requires both NF-Y and ADD1/SREBPs. Thus, SREBPs/ADD1 regulate not only genes involved in cholesterol homeostasis and fatty acid synthesis but also a key enzyme in glycerolipid synthesis.
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Abstract
PURPOSE To illustrate some of the radiation treatment techniques with asymmetric collimators in one field dimension. METHODS AND MATERIALS Treatment planning for various sites is done with an in-house developed treatment planning system. Dose distributions in the central plane are illustrated. RESULTS The use of asymmetric collimation, in addition to being a replacement for cerrobend and lead blocks, can facilitate treatment setup with boost fields and with half-beam asymmetric fields as in matching two adjacent fields, in avoiding nearby critical organ or tissue, and in tangential breast treatment. The use of asymmetric collimators would alter the dose distribution across the radiation field and should be accounted for during treatment planning. In conjunction with arc rotation or multiple asymmetric fields, two-dimensional conformal radiotherapy is possible. CONCLUSION The full potential of asymmetric collimation requires the use of a proper treatment planning algorithm. Some of the treatment techniques with asymmetric collimation in one field dimension are shown here.
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Lentiviral genomes with G-to-A hypermutation may result from Taq polymerase errors during polymerase chain reaction. AIDS Res Hum Retroviruses 1996; 12:1605-13. [PMID: 8947295 DOI: 10.1089/aid.1996.12.1605] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Retroviral genomes with a high frequency of G-to-A mutations are thought to originate during reverse transcription. Here we show that bursts of G-to-A mutation may also occur during DNA synthesis by Taq polymerase on a simian immunodeficiency proviral template. These G-to-A changes tend to occur at GpA and, to a lesser extent, GpG dinucleotides. Because the resulting sequences are like previously reported hypermutant human and simian immunodeficiency virus (HIV and SIV) genomes, it is important to design experiments that can clearly discriminate between Taq and reverse transcripts errors in studies of lentiviral G-to-A hypermutation.
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Synergistic binding of sterol regulatory element-binding protein and NF-Y to the farnesyl diphosphate synthase promoter is critical for sterol-regulated expression of the gene. J Biol Chem 1996; 271:24359-64. [PMID: 8798690 DOI: 10.1074/jbc.271.40.24359] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Sterol-regulated transcription of the farnesyl diphosphate (FPP) synthase gene is dependent on two cis elements in the proximal promoter. These elements, an inverted CCAAT box and sterol regulatory element 3 (SRE-3), bind NF-Y and sterol regulatory element-binding protein 1 (SREBP-1), respectively. We now demonstrate that the binding of recombinant SREBP-1 to its cognate site (SRE-3) within the FPP synthase promoter in vitro is enhanced by binding of NF-Y to the upstream inverted CCAAT box. Using an FPP synthase promoter fragment containing the binding sites for both NF-Y and SREBP-1 in gel mobility shift assays, we demonstrate that the addition of NF-Y increases the binding of SREBP-1 to SRE-3 over 20-fold. In contrast, NF-Y does not stimulate the binding of SREBP-1 to SRE-3 when the inverted CCAAT box is either mutated or 4 base pairs (bp) are inserted between the inverted CCAAT box and SRE-3. Promoter-reporter genes, containing either the wild-type FPP synthase promoter sequence or containing the 4-bp insertion between the inverted CCAAT box and SRE-3, were transiently transfected into cells. The activity of the wild-type promoter-reporter gene increased when the cells were either incubated in sterol-depleted medium or were co-transfected with an expression vector encoding transcriptionally active SREBP-1. This increase in activity was attenuated when the promoter contained the 4-bp insert, consistent with defective binding of SREBP to the promoter in vivo. These studies suggest that the binding of SREBP-1 to SRE-3 in the FPP synthase promoter, and subsequent stimulation of transcription, is dependent on synergistic binding and a functional interaction between SREBP-1 and NF-Y.
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Abstract
BACKGROUND AND PURPOSE The number of fractions of radiation therapy (RT) used after breast conserving surgery varies widely and accounts for a significant proportion of the workload in a modern radiotherapy department. Internationally, 'standard' therapy ranges from 3 to 7 weeks of daily treatment with or without a boost. Short RT schedules have the attraction of reducing workload but raise concern about an increased risk of late effects and poorer cosmetic outcome. MATERIALS AND METHODS In a randomized trial, 186 women with T1 or T2, pathologically node-negative breast cancer had cosmetic and various normal tissue effects data collected prospectively. The breast RT prescription was 44 Gy in 16 daily fractions to a tangent pair. RESULTS Median follow-up is 6.7 years. Actuarial 5-year breast recurrence was 6%. Overall cosmetic results at 5 years were good or excellent in 89% and 96% as reported by physicians and patients, respectively, and were stable between 2 and 5 years. Breast discomfort, erythema, edema and induration were related to both surgery and RT. At 5 years, 20% had breast discomfort, 18% had induration, 6% had erythema and 3% had some degree of breast edema. Fewer patients had these effects at 5 years than immediately after primary surgery. The presence of induration prior to starting RT was associated with a greater likelihood of breast induration 3 or more years following RT (P = 0.02). Thirteen percent of patients, generally those with large breasts, developed mild inframammary telangiectasia by 5 years. CONCLUSIONS Results are comparable to those reported from centers employing more conventional fractionation. Short fractionation produces acceptable cosmetic results for the majority of women if there are no contraindications to RT and in the absence of significant post-operative breast induration.
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Effect of acetylsalicylic acid on radiation and cosmetic results after conservative surgery for early breast cancer: a randomized trial. Radiother Oncol 1996; 41:1-6. [PMID: 8961361 DOI: 10.1016/s0167-8140(96)91825-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND AND PURPOSE Acetylsalicylic acid (ASA) can reduce the incidence of stroke and myocardial infarction by inhibiting platelet-fibrin thrombi in small blood vessels. To determine if ASA could reduce late effects of radiation therapy mediated by damage to small blood vessels, a prospective, placebo-controlled, double-blind trial was conducted in women with early breast cancer, receiving radiotherapy to the conserved breast. MATERIALS AND METHODS Cosmetic outcome and late radiotherapy effects were recorded prospectively for 186 women with T1 or T2, pathologically node-negative breast cancer treated with breast conservation and randomized to receive ASA (325 mg daily) or placebo for 1 year from the start of radiation therapy. Radiation was a tangent pair to the breast alone delivering a modal dose of 44 Gy in 16 daily fractions in 22-25 days. RESULTS Median follow-up is 6.5 years. The use of ASA has not had any effect on the acute (erythema, edema or discomfort) or late (induration, telangiectasia) effects of radiotherapy (all P > 0.10), the patients' or physicians' assessment of the cosmetic outcome (all P > 0.25) or rates of breast recurrence (P > 0.25). CONCLUSION ASA cannot be recommended to improve the outcome of radiotherapy complementing breast conserving surgery.
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Evaluation of a coagulase-negative variant of Staphylococcus aureus as a cause of intramammary infections in a herd of dairy cattle. J Am Vet Med Assoc 1996; 209:1143-6. [PMID: 8800266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A coagulase-negative variant of Staphylococcus aureus was identified in a herd of 250 lactating dairy cows. During testing of the entire herd, this strain of S aureus was isolated from aseptically collected milk samples of 25 cows. Cows with intramammary infections attributable to coagulase-negative S aureus had an increased somatic cell count in their milk, which was indicative of mastitis infection. Speciation of the Staphylococcus organisms was made, using a series of biochemical tests. A strain of a coagulase-positive S aureus also caused intramammary infections in the herd and shared identical biochemical characteristics with the coagulase-negative strain. Moreover, both strains could not be typed by the use of the International Set of Bovine Phages. Analysis of these findings indicated that a coagulase-negative variant of S aureus can cause intramammary infections in cattle, coagulase-negative variants of S aureus that cause mastitis can be more prevalent in herds than coagulase-positive variants, and clinicians should avoid misclassifying coagulase-negative S aureus as organisms that are clinically unimportant.
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Role for sterol regulatory element binding protein in the regulation of farnesyl diphosphate synthase and in the control of cellular levels of cholesterol and triglyceride: evidence from sterol regulation-defective cells. J Lipid Res 1996; 37:1712-21. [PMID: 8864955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
In order to define the factors involved in the regulation of farnesyl diphosphate (FPP) synthase, we used sterol regulation-defective (SRD) cell lines that constitutively express either high (SRD-2) or low (SRD-6) levels of transcriptionally active sterol regulatory element binding protein (SREBP). FPP synthase mRNA levels were high in SRD-2 cells and low in SRD-6 cells and were unaffected by the addition or removal of sterols from the media. In contrast, the mRNA levels in parental CHO-7 cells were regulated by sterols. SRD-2, SRD-6, and CHO-7 cells were also transiently transfected with plasmids containing FPP synthase promoter-reporter genes. Reporter gene activity was significantly higher in SRD-2 cells than in either SRD-6 or CHO-7 cells, consistent with a higher rate of transcription of the reporter gene in SRD-2 cells. The high expression of the reporter gene in SRD-2 cells was not observed when the FPP synthase promoter contained a three base pair mutation within an SREBP binding site, termed sterol regulatory element-3 (SRE-3). These observations are consistent with the hypothesis that high levels of transcription of the FPP synthase gene are dependent on the availability of transcriptionally active SREBP. We also demonstrate that the incorporation of radioactive acetate into both cholesterol and fatty acids was enhanced in SRD-2 cells as compared to CHO-7 or SRD-6 cells. Finally, we demonstrate that the concentrations of cholesterol, cholesteryl ester, and triglyceride were all significantly elevated in SRD-2 cells. We conclude that SREBP is involved not only in the regulation of FPP synthase and cholesterogenesis but also in fatty acid and triglyceride synthesis.
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Heterogeneity in human tumour hypoxic fraction using the comet assay. THE BRITISH JOURNAL OF CANCER. SUPPLEMENT 1996; 27:S191-S195. [PMID: 8763878 PMCID: PMC2149988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The alkaline comet assay has previously been used to estimate the fraction of radiobiologically hypoxic cells in tumours from patients undergoing palliative radiotherapy for advanced breast and head and neck cancer. Results obtained from fine needle aspirate biopsies (FNABs) using this method indicate considerable heterogeneity in hypoxic fraction between tumours. Heterogeneity between 3 aspirates taken from the same 10 tumours immediately following single doses of 3.5 to 5 Gy is now examined. Results indicate that a single fine needle aspirate is reasonably representative for DNA damage and DNA content. However, difficulties were encountered in obtaining an adequate sample of tumour cells after the final radiation treatment. The average hypoxic fraction decreased from 14% after the first dose to 9% after the last dose, and in 3 tumours which could be evaluated after both the first and last fraction, the hypoxic fraction decreased in two but increased in the third. Rejoining of DNA strand breaks was observed between sequential aspirates indicating that pooling of samples for analysis may not be advisable using this method.
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Teaching dietary counseling skills to residents: patient and physician outcomes. The CADRE Study Group. Am J Prev Med 1996; 12:259-65. [PMID: 8874689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Our objective was to determine whether an educational intervention and prompting intervention for physicians improved dietary counseling of patients with high blood cholesterol and resulted in beneficial changes in patients' diets and cholesterol levels. We instituted a factorial design, multicenter, randomized, placebo-controlled trial to test two interventions. We tested the trial at continuity care clinics of internal medicine residents at seven community and university medical centers in the northern and eastern United States. Our participants were 130 internal medicine residents and 254 adult outpatients with blood cholesterol levels of 240-300 mg/dL. Interventions included an educational program for resident physicians designed to improve their skills and confidence in dietary counseling (two one-hour sessions with specially prepared printed materials for use in counseling) and a prompting intervention, which was a fingerstick blood cholesterol determination prior to the patient's clinic visit. Resident physicians' knowledge, attitudes, and self-reported behaviors were assessed prior to the intervention and 10 months later using chart audits and questionnaires. Residents' behaviors were also assessed by exit interviews with patients. Patients' knowledge, attitudes, behaviors, and fingerstick blood cholesterol levels were measured at baseline and 10 months later. The educational program increased the percentage of physicians who were confident in providing effective dietary counseling (baseline of 26% to 67%-78%; P < .01). The prompting intervention approximately doubled the frequency of physician counseling (P = .0005) and increased the likelihood that patients would try to change their diets. When both interventions were combined, most outcomes were better, although not statistically significant. Cholesterol levels, however, decreased only marginally and were no different among groups at 10-month follow-up. Despite success in changing physicians' attitudes and behaviors and increasing patients' willingness to change their diets, there was no significant change in patients' cholesterol levels. Medical Subject Headings (MeSH): randomized controlled trial; cholesterol; patient education; behavior therapy; education, medical; diet.
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Neurologic complications following bone marrow transplantation for sickle cell disease. Bone Marrow Transplant 1996; 17:405-7. [PMID: 8704695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A boy with sickle cell anemia underwent bone marrow transplantation (BMT). He was normal on neurological examination, but had radiologic evidence of an old left frontal lobe infarct, multiple cerebral vascular stenoses and moyamoya collaterals. After BMT he developed seizures with extension of the infarct and subarachnoid hemorrhage. One year later angiography revealed worsening stenosis of the M1 segments of both middle cerebral arteries. At that time an increase in von Willebrand's factor with decreased large molecular weight multimers (LvWF) was observed. We speculate that LvWF dependent, shear-induced platelet aggregation, together with endothelial damage may have contributed to the development of neurologic complications in this patient.
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