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51.
Platelet endothelial cell adhesion molecule-1 (PECAM-1) is a cell-cell adhesion molecule that is expressed on circulating platelets, on leukocytes, and at the intercellular junctions of vascular endothelial cells and mediates the interactions of these cells during the process of transendothelial cell migration. The cDNA for PECAM-1 encodes an open reading frame of 738 amino acids (aa) that is organized into a 27- aa signal peptide, a 574-aa extracellular domain composed of 6 Ig homology units, and a relatively long cytoplasmic tail of 118 aa containing multiple sites for posttranslational modification and postreceptor signal transduction. To provide a molecular basis for the precise evaluation of the structure and function of this transmembrane glycoprotein, we have determined the organization of the human PECAM-1 gene. The PECAM-1 gene, which has been localized to human chromosome 17, is a single-copy gene of approximately 65 kb in length and is broken into 16 exons by introns ranging in size from 86 to greater than 12,000 bp in length. Typical of other members of the Ig superfamily, each of the extracellular Ig homology domains is encoded by a separate exon, consistent with PECAM-1 having arisen by gene duplication and exon shuffling of ancestral Ig superfamily genes. However, the cytoplasmic domain was found to be surprisingly complex, being encoded by seven short exons that may represent discrete functional entities. Alternative splicing of the cytoplasmic tail appears to generate multiple PECAM-1 isoforms that may regulate phosphorylation, cytoskeletal association, and affinity modulation of the mature protein. Finally, a processed pseudogene having 76% identity with PECAM- 1 cDNA was identified and localized to human chromosome 3. These findings should have important implications for structure/function analysis of PECAM-1 and its role in vascular adhesive interactions. 相似文献
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We report the successful long-term engraftment of normal male donor bone marrow (BM) transfused into noncytoablated female mice, challenging the assumption that "niches" need to be created for marrow to engraft. We have used chromosomal banding and Southern blot analysis to identify transplanted male marrow cells, and shown the long-term stability of the chimeric marrows. Balb/C, BDF1, or CBA-J female hosts (no irradiation) received for 5 consecutive days 40 x 10(6) male cells (per day) of the same strain, and repopulation patterns were observed. Parallel studies were performed using tibia/femur equivalents of normal marrow or marrow from Balb/C mice pretreated 6 days previously with 150 mg/kg 5-fluorouracil (5-FU). Chromosome banding techniques showed that 5% to 46% of marrow cells were male 3 to 9 months posttransplant with normal donor marrow. Southern blot analysis, using the pY2 probe, showed continued engraftment at 21 to 25 months posttransplant, ranging from 15% to 42% male engrafted cells in marrow. Normal donor male marrow engrafted significantly better than 5-FU-pretreated male marrow as shown 1 to 12 months posttransplant in non-cytoablated female recipients. Percentages of male engrafted cells in BM ranged from 23% to 78% for recipients of normal donor marrow and from 0.1% to 39% for recipients of 5-FU marrow. Mean engraftment for 6 mice receiving normal marrow was 38%, whereas that for 6 mice receiving post-5-FU marrow was 8%, as assayed 1 to 3 months posttransplant. At 10 to 12 months, mean engraftment for the normal donor group was 46%, compared with 16% for the 5-FU group. The patterns of engraftment with normal and 5-FU marrow were similar for spleen and thymus. These results show that long-term chimerism can be established after transplantation of normal donor marrow to normal nonirradiated host mice and indicate that marrow spaces do not have to be created for successful engraftment. They suggest that transplanted marrow competes equally with host marrow for marrow space. Finally, these data show that post-5-FU Balb/C male marrow is markedly inferior in the repopulation of Balb/C female host marrow, spleen, and thymus, and suggest that this population of cells may not be the ideal population for gene transfer studies. 相似文献
53.
RJ Mascarenhas ND Hapangama PJ Mews A Burlakoti S Ranjitkar 《Australian dental journal》2019,64(1):106-110
Chronic orofacial pain of neuropathic origin can present diagnostic and management dilemmas to dental practitioners and also affects the patient's quality of life. Intracranial aneurysms are a potential cause of stroke (e.g. sub‐arachnoid haemorrhage) that is usually associated with, high rates of mortality and morbidity. A patient who had been previously managed for symptoms of temporomandibular joint disorder (TMD) presented with sharp, shooting pain of moderate intensity. It was precipitated by swallowing, and radiated to the right throat, posterior border of the mandible, ear and temporomandibular joint. Clinical and radiological investigations ruled out odontogenic pain, TMD and other more common types of facial pain. Magnetic resonance imaging revealed a 7 × 6 mm aneurysm in the right middle cerebral artery (MCA) which was subsequently surgically clipped. Interestingly, the facial pain resolved after this procedure. Compression of the insular region of the brain innervated by the trigeminal, glossopharyngeal and vagus nerves provides a plausible explanation for the pain reported. To our knowledge, this is the first case of facial neuralgia associated with an aneurysm in the MCA which emphasizes the importance of a multidisciplinary approach in the diagnosis and management of unusual cases of chronic orofacial pain. 相似文献
54.
Daniela N Schulz Eline S Smit Nicola E Stanczyk Stef PJ Kremers Hein de Vries Silvia MAA Evers 《Journal of medical Internet research》2014,16(3)
Background
Different studies have reported the effectiveness of Web-based computer-tailored lifestyle interventions, but economic evaluations of these interventions are scarce.Objective
The objective was to assess the cost-effectiveness and cost-utility of a sequential and a simultaneous Web-based computer-tailored lifestyle intervention for adults compared to a control group.Methods
The economic evaluation, conducted from a societal perspective, was part of a 2-year randomized controlled trial including 3 study groups. All groups received personalized health risk appraisals based on the guidelines for physical activity, fruit intake, vegetable intake, alcohol consumption, and smoking. Additionally, respondents in the sequential condition received personal advice about one lifestyle behavior in the first year and a second behavior in the second year; respondents in the simultaneous condition received personal advice about all unhealthy behaviors in both years. During a period of 24 months, health care use, medication use, absenteeism from work, and quality of life (EQ-5D-3L) were assessed every 3 months using Web-based questionnaires. Demographics were assessed at baseline, and lifestyle behaviors were assessed at both baseline and after 24 months. Cost-effectiveness and cost-utility analyses were performed based on the outcome measures lifestyle factor (the number of guidelines respondents adhered to) and quality of life, respectively. We accounted for uncertainty by using bootstrapping techniques and sensitivity analyses.Results
A total of 1733 respondents were included in the analyses. From a willingness to pay of €4594 per additional guideline met, the sequential intervention (n=552) was likely to be the most cost-effective, whereas from a willingness to pay of €10,850, the simultaneous intervention (n=517) was likely to be most cost-effective. The control condition (n=664) appeared to be preferred with regard to quality of life.Conclusions
Both the sequential and the simultaneous lifestyle interventions were likely to be cost-effective when it concerned the lifestyle factor, whereas the control condition was when it concerned quality of life. However, there is no accepted cutoff point for the willingness to pay per gain in lifestyle behaviors, making it impossible to draw firm conclusions. Further economic evaluations of lifestyle interventions are needed.Trial Registration
Dutch Trial Register NTR2168; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2168 (Archived by WebCite at http://www.webcitation.org/6MbUqttYB). 相似文献55.
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Accurate pregnancy dating is vital to obstetric management. However, first trimester fetal charts commonly used in Australia rely on data reported more than three decades ago. This study reports first trimester dating and growth charts for crown‐rump length between 5 and 14 weeks of gestation and biparietal diameter between 9 and 14 weeks of gestation on an Australia population using modern real‐time ultrasound equipment. All consenting eligible women attending a large Sydney clinic for first trimester ultrasound between March 2005 and December 2006 were recruited. Measurements were carried out to Australasian Society for Ultrasound in Medicine standard protocols. Statistical analyses were undertaken using polynomial regression models and thorough diagnostic checks made. Overall 396 eligible women consented to the study, with 268 between 9 and 14 weeks of gestation. The average participant age was 34 years (range 22–45 years), 371 and all yielded valid biometry measurements. Equations, means and 90% reference intervals for crown‐rump length measurements and biparietal diameter measurements were derived using polynomial regression models. Thorough residual and diagnostic checks were made. Once validated by others, we believe they will warrant consideration for use by Australasian Society for Ultrasound in Medicine. 相似文献
60.
ÅM Jakobson A Kreuger Ö Mortimer S Henningsson H Seidel PJ Moe 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(4):359-361
Two patients aged 11 and four years, were accidentally given a 10-fold overdose of intrathecal methotrexate while being treated for malignant disease. Neither patient developed any signs of neurotoxicity and exchange of lumbar cerebro-spinal fluid was started 3 and 5 h later, respectively. In one of the patients, who received 120 mg of methotrexate intrathecally, 31% of the given dose was recovered during 2 h of cerebrospinal fluid exchange that was started 3 h after the accidental overdosage. No sequelae were observed in any of the patients. Cerebrospinal fluid exchange is safe and can be recommended in all cases of intrathecal methotrexate overdosage. Ventriculo-cisternal perfusion is not necessary in cases of a 10-fold overdose if the patient has no signs of acute neurotoxicity. 相似文献