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Mouse peritoneal cells (PC) in culture produce auto-antibodies lyzing bromelain-treated mouse erythrocytes (MRBCbr). These auto-antibodies have been obtained in an homogeneous form in substantial amounts after cell fusion of PC with myeloma X63.Ag8. They have been identified as the anti-Hb-auto-antibodies described by us in 1980. Once coupled to fluorescent microspheres (Ms), they were used to detect the corresponding antigen. It was found that the specific antigen was not only present on the surface of all MRBCbr but also, in a much smaller proportion, on some normal MRBC. Its distribution is not restricted to the mouse: pigeon RBC is stained heavily; human red cells give, more or less, positive reaction, according to their blood group. Some species, as horse RBC, are consistently negative. The opportunity offered by the fluorescent microspheres technique to trace the antigen recognized by the Hb-auto-antibody in the mouse tissues and on cells from other species should lead to a better understanding of the cross-antigenicity of many RBC and of the peculiar auto-immune process involving MRBCbr in the mouse. 相似文献
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The patterns of exochorion ornaments on eggs of seven South American Lutzomyia sand fly species were analyzed by scanning electron microscopy (SEM): Lutzomyia (Lutzomyia) cruzi (Mangabeira 1938), Lutzomyia (Micropygomyia) evandroi (Costa Lima and Antunes 1936), L. (Nyssomyia) intermedia (Lutz and Neiva 1912), L. longipalpis (Lutz and Neiva 1912), L. migonei (Franca 1920), L. (Nyssomyia) neivai (Pinto 1926), and L. renei (Martins, Falcao, and Silva 1957). Different patterns were observed, which showed the distinction between some species. Egg ornaments in L. cruzi and L. longipalpis appear as single, parallel, unconnected ridges, whereas eggs of L. migonei appear as single, parallel, connected ridges. Eggs of L. (Nyssomyia) intermedia and L. (N.) neivai present a new variation of the single, unconnected, parallel ridges pattern: small tubercles are present, distributed between the ridges. Eggs of L. renei present an elliptical pattern, with most structures connected by straight ridges. Eggs of L. (M.) evandroi present a polygonal pattern, with alternate rows of small and large hexagons. Our data emphasize the advantages of the SEM approach in the study of the exochorion patterns of Lutzomyia eggs and in the distinction of the sand fly species. 相似文献
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Ren Verreault Danielle Laurin Joan Lindsay Gaston De Serres 《Canadian Medical Association journal》2001,165(11):1495-1498
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Molly E. Baumann Danielle M. DeBruler Britani N. Blackstone Rebecca A. Coffey Steven T. Boyce Dorothy M. Supp J. Kevin Bailey Heather M. Powell 《Burns : journal of the International Society for Burn Injuries》2021,47(2):466-478
IntroductionDetermining the efficacy of anti-scar technologies can be difficult as qualitative, subjective assessments are often utilized instead of systematic, objective measures. Perceptions regarding the reliability of instruments for quantitative measurements along with their high cost and increased data collection time may discourage their use, leading to use of scar scales which are relatively quick and low-cost. To directly evaluate the reliability of instruments for quantitative measurements of scar properties, instruments and two qualitative scales were compared by assessing a variety of cutaneous scars.MethodsScar height and surface texture were evaluated using a 3D scanner and a mold/cast technique. Scar color was evaluated by using a spectroscopy-based tool, the Mexameter®, and digital photography with image analysis. Scar biomechanics were evaluated using the BTC-2000?, Dermal Torque Meter (DTM®), and ballistometer®. The Vancouver Scar Scale (VSS) and Patient and Observer Scar Assessment Scale (POSAS) were used to qualitatively evaluate the same scar properties. Intraclass correlation coefficients (ICC) were used to determine inter- and intra-user reliability (poor, moderate, good, excellent) with all instruments and the kappa reliability statistic was used to asses inter-user reliability (poor, fair, moderate, good, very good) for VSS and POSAS. Time for measurement collection and after collection analysis was also recorded.ResultsThe Mexameter® was the most reliable method for evaluating erythema and pigmentation compared to digital photography and image processing, POSAS and VSS. Digital photography and analysis was more reliable than POSAS and VSS. Assessment of scar height was significantly more reliable when using a 3D scanner versus VSS and POSAS. The 3D scanner and mold-cast techniques also offered an additional benefit of providing an absolute value of scar height relative to the surrounding tissue. Intra-user reliability for all mechanical tests was moderate to good. Inter-user reliability was greater when using the BTC-2000? and ballistometer® versus the DTM®. All quantitative measurements took less than 90 s for collection, with the exception of the mold/cast technique.ConclusionNon-invasive instruments allow scar properties to be quantitatively assessed with high sensitivity and as a function of time and/or treatment without the need for biopsy collection. Overall, the reliability of scar assessments was significantly improved when quantitative instruments were utilized versus scar scales. Quantitative assessment of color and biomechanics were swift, requiring less than 90 s per measurement while assessments of texture and height required additional analysis time after collection. With proper training of clinical staff and well-defined protocols for measurement collection, reliable, quantitative assessments of scar properties can be collected with little disruption to the clinical workflow. 相似文献
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Michelle Lonergan Alain Brunet Marjolaine Rivest-Beauregard Danielle Groleau 《Stress and health》2021,37(1):19-31
According to a growing body of research, betrayal by a romantic partner is increasingly considered as a form of interpersonal trauma. Between 30% and 60% of betrayed individuals experience symptoms of post-traumatic stress disorder (PTSD), depression and anxiety to clinically meaningful levels. From a clinical perspective, this constellation of symptoms can be conceptualized as a stressor-related adjustment disorder. Yet, no qualitative research has examined the association between romantic betrayal and traumatic stress from the perspective of betrayed individuals. Face-to-face semi-structured interviews were conducted with 13 participants who had completed a clinical trial for a new treatment for adjustment disorder stemming from betrayal. Data were analysed using thematic content analysis. Although betrayal was experienced as a shocking and destabilizing event, and participants used trauma or ‘feeling traumatized’ as a metaphor to describe their experience, few had constructed their reaction as traumatic stress. In fact, participants reported experiencing difficulties understanding the intensity of their experience. However, when exposed to external sources (e.g., books and interviews by psychologists and researchers) that used a trauma and PTSD framework to explain the effects of betrayal, participants reported feeling clarity, validation and relief. Findings are discussed in the light of theoretical and clinical implications. 相似文献
18.
Franklin Patricia D. Zheng Hua Bond Christina Lavallee Danielle C. 《Quality of life research》2021,30(11):3171-3178
Quality of Life Research - New informatics tools can transform evidence-based information to individualized predictive reports to serve shared decisions in clinic. We developed a web-based system... 相似文献
19.
Jan M. West Danielle C. Humphris D. George Stephenson 《Journal of muscle research and cell motility》1995,16(3):267-284
Summary Long-(SL>6m) and short-sarcomere (SL<4m) fibres were isolated from the claw muscle of the yabby (Cherax destructor) during limb regeneration and at different stages of the moult cycle. Long-sarcomere fibres were more susceptible to the changes resulting from the moult-induced atrophy compared with the short-sarcomere fibres. Signs of atrophy included fibre erosion, loss of myosin filaments, a reduction in the diameter of myosin filaments and changes associated with the Z line. The intracellular structure of the fibres, however, remained intact in both fibre types. Fibres taken immediately prior to ecdysis could not be fully activated with Ca2+ or Sr2+ without breaking. In contrast fibres taken within 4 h after ecdysis could develop and maintain full force when activated by Ca2+ or Sr2+. The results suggest that loss of myofibrillar proteins via the moult-induced atrophy and/or events associated with fibre elongation may occur in the period just prior to ecdysis and that these changes may be responsible for the fibres inability to function during the premoult stage. Results from this study showed that short-sarcomere fibres add sarcomeres by at least two different mechanisms (1) transverse sarcomere splitting and (2) Z line splitting. Long-sarcomere fibres appear to be elongated by mechanism (s) other than those used by short-sarcomere fibres which possibly involve large electron dense structures which are positioned between the myofibrils and within the A and I bands. Results from the regenerating chelae limb bud showed that sarcomeres form from separate units comprising myosin filaments and actin filaments anchored into Z lines respectively. These sub-sarcomeric units then join together to form sarcomeres. Myofibril formation is aided by electron dense regions which are closely associated with the membrane system. These fibres although short in length and still within the non-functional limb bud could be activated by Ca2+ and Sr2+ suggesting that full fibre function exists before the chelae become functional. Regenerating muscle fibres consisted predominately of fibres with short-sarcomeres. 相似文献
20.