58 research outputs found

    Revisiting the issue: can the reading for serologic reactivity following 37°C incubation be omitted?

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    Omitting the 37°C reading from screening tests for unexpected antibodies results in failure to detect some Rh, K, and Jk agglutinins of potential significance (wanted positives). However, this measure avoids unwanted positive tests due to cold agglutinins. STUDY DESIGN AND METHODS : Using data from prior publications, actual risk calculations (ARCs) were made to predict the risk of eliminating the 37°C reading, pretransfusion direct antiglobulin test (DAT), and routine indirect antiglobulin crossmatch (IAT-XM). ARCs used the equation: wanted positives missed × 0.34 (or 0.80) × 5 × percent antigen-positive, where 0.34 = percent of patients transfused (ARCs for 37°C reading and DAT); 0.80 = percent of crossmatched patients transfused (ARCs for IAT-XM); 5 = average number of units transfused. Following elimination of the 37°C reading, the impact of this change on patient care was monitored. Antibody detection and identification data and transfusion reaction reports for 6 months after the change were reviewed. Recently transfused patients with new antibodies were evaluated for immune hemolysis by review of clinical and laboratory data. The findings were compared with those from the same dates of the preceding year. RESULTS : The risk of transfusing incompatible blood by eliminating the DAT, IAT-XM, and 37°C reading is approximately 1:13,000, 1:2,000, and 1:2,400 units transfused, respectively. The cumulative risk from eliminating all three tests is approximately. 1:1,000 units. With respect to the 37°C reading, there were no differences between the pre-change and post-change study periods in the incidence of reported transfusion reactions or cases of immune hemolysis associated with newly formed antibodies. However, unwanted positive tests decreased from 162 to 61 following elimination of the 37°C reading. This represents a decrease of 20 percent in the number of samples requiring antibody identification annually. CONCLUSIONS : Eliminating the 37°C reading from pretransfusion antibody screening tests imposes less risk than omitting the routine IAT-XM, and it avoids the time and costs of evaluating unwanted positive tests, thus reducing expenditures and delays in patient care.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74728/1/j.1537-2995.1999.39399219287.x.pd

    Enrichment of Organic Carbon in Sediment Transport by Interrill and Rill Erosion Processes

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    Erosion and loss of organic carbon (OC) result in degradation of the soil surface. Rill and interrill erosion processes on a silt loam soil were examined in laboratory rainfall and flume experiments. These experiments showed that rill and interrill erosion processes have contrasting impacts on enrichment of OC in transported sediment. Rill erosion was found to be nonselective, while for interrill erosion the enrichment ratio of OC, EROC, varied between 0.9 and 2.6 and was inversely related to the unit sediment discharge. At unit sediment discharge values >0.0017 kg s(-1) m(-1), the EROC remained equal to 1. The enrichment process was not influenced by raindrop impact. Enrichment of OC by "aggregate stripping" was found to be unimportant in our study. This was attributed to the low aggregate stability of the soil and the equal distribution of OC within the different soil aggregate classes

    Utilising biological geotextiles: Introduction to the BORASSUS project and global perspectives

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    Field and laboratory studies indicate that utilisation of biological geotextiles constructed from palm-leaves and other selected organic materials are an effective, sustainable and economically viable soil conservation technique. The three-year plus (1 July 2005–28 February 2009) EU-funded BORASSUS Project (contract no. INCO-CT-2005-510745) evaluated the long-term effectiveness of biological geotextiles in controlling soil erosion and assessing their sustainability and economic viability. These studies progressed in ten countries, both in the ‘industrial north’ (in Europe) and in the ‘developing south’ (Africa, South America and South East Asia). The studied countries in the ‘developing south’ included Brazil, China, The Gambia, South Africa, Thailand and Vietnam. The ‘industrial north’ countries included Belgium, Hungary, Lithuania and the UK. The main findings of these studies are summarised in this paper and thematic information is presented in the other four papers in this Special Issue. Biological geotextiles offer potentially novel bioengineering solutions to environmental problems, including technologies for soil conservation, sustainable plant production and use of indigenous plants, improved ecosystem management by decreasing deforestation, improving agroforestry and cost-effective biogeotextile applications in diverse environments. Biogeotextiles may provide socio-economic platforms for sustainable development and the benefits for developing countries may include poverty alleviation, engagement of local people as stakeholders, employment for disadvantaged groups, small and medium enterprise (SME) development, earning hard currency, environmental education and local community involvement in land reclamation and environmental education programmes. These benefits are achieved through: (i) promotion of sustainable and environmentally friendly palm-agriculture to discourage deforestation, promoting both reforestation and agroforestry; (ii) construction of biogeotextiles enabling development of a rural labour-intensive industry, particularly encouraging employment of socially disadvantaged groups and (iii) export of biogeotextiles to industrialised countries could earn hard currency for developing economies, based on the principles of fair trade. Research and development activities of the BORASSUS Project have improved our knowledge on the effect of biogeotextile mats on the micro- and macro-soil environments and at larger scales through controlled laboratory and field experiments in diverse environments

    Primary cutaneous malignant perivascular epithelioid cell tumor: Case of a rare tumor with review of the literature

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    Perivascular epithelioid cell tumors (PEComas) are mesenchymal neoplasms with characteristic epithelioid or spindled cytomorphology that typically grow around blood vessels. These tumors are phenotypically and immunohistochemically distinct, expressing markers of both melanocytic and smooth muscle differentiation. Herein, we describe a case of histopathologically malignant cutaneous PEComa without metastatic spread, with review of the pertinent literature. Telescoping punch biopsy demonstrated an epithelioid neoplasm with marked atypia, hypercellularity, and increased mitotic activity. Immunohistochemical stains for HMB‐45, NK1‐C3, PGP9.5, MiTF, CD10, and CD68 were positive within tumor cells. In addition, there was diffuse expression of caldesmon and focal cytoplasmic staining for smooth muscle actin on the excision specimen. The patient underwent treatment with surgical excision with adjuvant radiation and surveillance computed tomography (CT). The patient remains free of recurrence or metastatic disease after 10 months of follow‐up. To our knowledge, this is only the third reported case of a malignant cutaneous PEComa reported in the literature to date.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/168484/1/cup14034.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/168484/2/cup14034_am.pd

    Primary cutaneous malignant perivascular epithelioid cell tumor: Case of a rare tumor with review of the literature

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    Perivascular epithelioid cell tumors (PEComas) are mesenchymal neoplasms with characteristic epithelioid or spindled cytomorphology that typically grow around blood vessels. These tumors are phenotypically and immunohistochemically distinct, expressing markers of both melanocytic and smooth muscle differentiation. Herein, we describe a case of histopathologically malignant cutaneous PEComa without metastatic spread, with review of the pertinent literature. Telescoping punch biopsy demonstrated an epithelioid neoplasm with marked atypia, hypercellularity, and increased mitotic activity. Immunohistochemical stains for HMB‐45, NK1‐C3, PGP9.5, MiTF, CD10, and CD68 were positive within tumor cells. In addition, there was diffuse expression of caldesmon and focal cytoplasmic staining for smooth muscle actin on the excision specimen. The patient underwent treatment with surgical excision with adjuvant radiation and surveillance computed tomography (CT). The patient remains free of recurrence or metastatic disease after 10 months of follow‐up. To our knowledge, this is only the third reported case of a malignant cutaneous PEComa reported in the literature to date.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/168484/1/cup14034.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/168484/2/cup14034_am.pd
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