Standardization of serological tests for detecting anti-Trypanosoma cruzi antibodies in dogs

This paper reports on the standardization of four serological reactions currently used in human serodiagnosis for the detection of anti-Trypanosoma cruzi antibodies in naturally and experimentally infected dogs. Indirect immunofluorescence test (IFAT) and hemagglutination test (IHAT) were standardized, and complement fixation test (CFT) and direct agglutination test (DAT) were used for diagnostic confirmation. Four hundred and eighty one mongrel dogs that were studied by xenodiagnosis were used: (1) parasitemic dogs of two localities of endemic area (EA) of Santiago del Estero province in Argentina (n = 134); (2) non-parasitemic dogs of the same area (n = 285); (3) dogs experimentally infected with T. cruzi in the patent period (n = 6); (4) non-infected dogs (n = 56) which were born in the city of Buenos Aires (BA), one non-EA for Chagas' disease. For IFAT, parasitemic dogs EA showed 95% of reactive sera. Non parasitemic dogs EA showed 77% of non reactive sera. None sera from BA were reactive for dilutions higher than four. For IHAT, 84% of sera of parasitemic dogs EA showed serological reactivity and among non parasitemic dogs BA, 61% were non reactive, while the remainder showed at most titres of 1/16. The cut-off titres for IFAT and IHAT were 1/16 and 1/32 respectively, and for CFT and DAT 1/1 and 1/128 respectively. Sensitivity for IFAT, IHAT, CF and DAT were 95%, 84%, 97% and 95% respectively.

Standardization and evaluation of ELISA for the serodiagnosis of amoebic liver abscess

An ELISA test for the serological diagnosisof amoebic liver abscess (ALA) was standardized and evaluated in sera from three groups of patients: (1) three patients with diagnosis confirmed by isolation of the parasite,(2) thirty seven patients with diagnosis established by clinical findings and ultrasound studies and (3) seven patients whose diagnosis were established by clinical findings and a positive double immunodifusion test. Ninety one serum samples from healthy subjects and 22 from patients with other liver or parasitic diseases were also included in the study. the optimum concentration of Entamoeba histolytica antigen was 1.25 µg/ml and optimum dilutions of serum and anti-human IgG-alkaline phosphatase conjugate were 1:400 and 1:4000 respectively. The cut-off point of the ELISA test in this study was an absorbance value of 0.34. The test parameters were: sensitivity = 95.7 per cent, specificty = 100 per cent, positive predictive value = 100 per cent and negative predictive value = 98.2 per cent.The ELISA test was found to be of great use as a diagnostic tool for the establishment of amoebic etiology in patients with clinical supposition of ALA. The test could also be used for seroepidemiological surveys of the prevalence of invasive amoebiasis in a given population, since it allows the processing of a greater number of samples at a lower cost tahn other serological tests.

Standardization of Stroke Perfusion CT for Reperfusion Therapy

With the advances in terms of perfusion imaging, the "time is brain" approach used for acute reperfusion therapy in ischemic stroke patients is slowly being replaced by a "penumbra is brain" or "imaging is brain" approach. But the concept of penumbra-guided reperfusion therapy has not been validated. The lack of standardization in penumbral imaging is one of the main contributing factors for this absence of validation. This article reviews the issues underlying the lack of standardization of perfusion-CT for penumbra imaging, and offers avenues to remedy this situation

Standardization of bovine macrophage monolayers and isolation and culture of trypanosomes

We describe a method for culturing over 90% pure bovine macrophages from peripheral blood mononuclear cells separated with Nycoprep. The cells were cultured for 12 days and then stained with esterase and with anti CD14 to test for purity. The method is reproducible and ensures an adequate number of cells for immunological research. Additionally, we report the unexpected finding of Trypanosoma trypomastigotes in our macrophage cultures from bovines belonging to a geographic area from which no bovine trypanosomes had been reported before.

Towards standardization of UV eye protection: what can be learned from photodermatology?

While knowledge about standardization of skin protection against ultraviolet radiation (UVR) has progressed over the past few decades, there is no uniform and generally accepted standardized measurement for UV eye protection. The literature provides solid evidence that UV can induce considerable damage to structures of the eye. As well as damaging the eyelids and periorbital skin, chronic UV exposure may also affect the conjunctiva and lens. Clinically, this damage can manifest as skin cancer and premature skin ageing as well as the development of pterygia and premature cortical cataracts. Modern eye protection, used daily, offers the opportunity to prevent these adverse sequelae of lifelong UV exposure. A standardized, reliable and comprehensive label for consumers and professionals is currently lacking. In this review we (i) summarize the existing literature about UV radiation-induced damage to the eye and surrounding skin; (ii) review the recent technological advances in UV protection by means of lenses; (iii) review the definition of the Eye-Sun Protection Factor (E-SPF®), which describes the intrinsic UV protection properties of lenses and lens coating materials based on their capacity to absorb or reflect UV radiation; and (iv) propose a strategy for establishing the biological relevance of the E-SPF.

Standardization of in-house polymerase chain reaction for the identification of Mycobacterium tuberculosis at the reference tropical disease hospital in the State of Goiás, Brazil

This study compares smear, growth in Lowenstein-Jensen medium, and in-house polymerase chain reaction (PCR) techniques for the detection of Mycobacterium tuberculosis. A total of 72 specimens from 72 patients with clinical symptoms of tuberculosis, including 70 sputum and two bronchial aspirate samples, were tested in parallel by smear, culture, and in-house PCR techniques. From these, 48 (66.6%) were negative by the 3 methods, 2 (2.8%) were smear positive and negative by culture and in-house PCR, 11 (15.3%) were both smear and culture negative, and in-house PCR positive, 7 (9.7%) were positive by the 3 methods, 2 (2.8%) were positive by smear and culture, and negative by PCR, 2 (2.8%) were positive by culture and PCR, but smear negative. After the resolution of discrepancies in PCR results, the sensitivity and specificity for in-house PCR technique to M. tuberculosis relative to the culture, were 81.8% and 81.9%, respectively. These results confirm that this method, in-house PCR, may be a sensitive and specific technique for M. tuberculosis detection, occurring in both positive and negative smear and negative cultures.

Services standardization in the United-States and in Europe: an institutional analysis of private authority

This contribution explores the role of international standards in the rules governing the internationalisation of the service economy. It analyses on a cross-institutional basis patterns of authority in the institutional setting of service standards in the European and Amercian context. The entry into force of the World Trade Organisation (WTO) in 1995 gave international standards a major role in harmonising the technical specifications of goods and services traded on the global market Despite the careful wording of the WTO, a whole range of international bodies still have the capacity to define generic as well as detailed technical specifications affecting how swelling offshore services are expected to be traded on worldwide basis. The analysis relies on global political economy approaches to identify constitutive patterns of authority mediating between the political and the economic spheres on a transnational space. It extends to the area of service standards the assumption that the process of globalisation is not opposing states and markets, but a joint expression of both of them including new patterns and agents of structural change through formal and informal power and regulatory practices. The paper argues that service standards reflect the significant development of a form of transnational hybrid authority, that blurs the distinction between private and public actors, whose scope spread all along from physical measures to societal values, and which reinforces the deterritorialisation of regulatory practices in contemporary capitalism. It provides evidence of this argument by analysing the current European strategy regarding service standardization in response to several programming mandate of the European Commission and the American views on the future development of service standards.

How to Assess Histology in Eosinophilic Esophagitis: Standardization by the EEsAI Histopathology Questionnaire

Background and Aims: The international EEsAI study group iscurrently developing the first activity index specific forEosinophilic Esophagitis (EoE). So far histologic assessment inEoE i s not standardized but urgently needed to harmonizehistologic endpoints i n clinical trials. G oal: To develop andevaluate the EEsAI histopathology questionnaire.Methods: B ased o n multiple Delphi r ounds w ith national a ndinternational ( Europe and North America) E oE e xperthistopathologists and gastroenterologists, w e have d evelopedthe EEsAI histopathology questionnaire.Results: T he EEsAI histopathology questionnaire t akes i ntoaccount the following items: number of eosinphils per highpower field, pattern of i nflammation, eosinophil abscesses,basal l ayer e nlargement, and lamina propria f ibrosis. D istinctdefinitions a nd categories f or every item were established byagreement among experts. EoE expert pathologists had amedian of 22 minutes to complete the questionnaire and judgedit as well feasible. The histopathology questionnaire was pilotedin 20 patients and is currently evaluated in a cohort of 150 adultEoE patients.Conclusions: T he EEsAI histopathology questionnaire is thefirst tool that assesses EoE severity according to clearly definedhistologic criteria. These definitions, as well as their categories,established by i nternational E oE e xpert pathologists, w illstandardize h istologic EoE s everity assessment and therebyfacilitate the comparison of histologic outcome measures inclinical trials.

Liver safety assessment: required data elements and best practices for data collection and standardization in clinical trials.

A workshop was convened to discuss best practices for the assessment of drug-induced liver injury (DILI) in clinical trials. In a breakout session, workshop attendees discussed necessary data elements and standards for the accurate measurement of DILI risk associated with new therapeutic agents in clinical trials. There was agreement that in order to achieve this goal the systematic acquisition of protocol-specified clinical measures and lab specimens from all study subjects is crucial. In addition, standard DILI terms that address the diverse clinical and pathologic signatures of DILI were considered essential. There was a strong consensus that clinical and lab analyses necessary for the evaluation of cases of acute liver injury should be consistent with the US Food and Drug Administration (FDA) guidance on pre-marketing risk assessment of DILI in clinical trials issued in 2009. A recommendation that liver injury case review and management be guided by clinicians with hepatologic expertise was made. Of note, there was agreement that emerging DILI signals should prompt the systematic collection of candidate pharmacogenomic, proteomic and/or metabonomic biomarkers from all study subjects. The use of emerging standardized clinical terminology, CRFs and graphic tools for data review to enable harmonization across clinical trials was strongly encouraged. Many of the recommendations made in the breakout session are in alignment with those made in the other parallel sessions on methodology to assess clinical liver safety data, causality assessment for suspected DILI, and liver safety assessment in special populations (hepatitis B, C, and oncology trials). Nonetheless, a few outstanding issues remain for future consideration.

Guidelines for imaging retinoblastoma: imaging principles and MRI standardization.

Retinoblastoma is the most common intraocular tumor in children. The diagnosis is usually established by the ophthalmologist on the basis of fundoscopy and US. Together with US, high-resolution MRI has emerged as an important imaging modality for pretreatment assessment, i.e. for diagnostic confirmation, detection of local tumor extent, detection of associated developmental malformation of the brain and detection of associated intracranial primitive neuroectodermal tumor (trilateral retinoblastoma). Minimum requirements for pretreatment diagnostic evaluation of retinoblastoma or mimicking lesions are presented, based on consensus among members of the European Retinoblastoma Imaging Collaboration (ERIC). The most appropriate techniques for imaging in a child with leukocoria are reviewed. CT is no longer recommended. Implementation of a standardized MRI protocol for retinoblastoma in clinical practice may benefit children worldwide, especially those with hereditary retinoblastoma, since a decreased use of CT reduces the exposure to ionizing radiation.

Competing engines of growth: Innovation and standardization

We study a dynamic general equilibrium model where innovation takes theform of the introduction of new goods whose production requires skilled workers.Innovation is followed by a costly process of standardization, whereby these newgoods are adapted to be produced using unskilled labor. Our framework highlightsa number of novel results. First, standardization is both an engine of growth anda potential barrier to it. As a result, growth is an inverse U-shaped function ofthe standardization rate (and of competition). Second, we characterize the growthand welfare maximizing speed of standardization. We show how optimal protection of intellectual property rights affecting the cost of standardization vary withthe skill-endowment, the elasticity of substitution between goods and other parameters. Third, we show that, depending on how competition between innovatingand standardizing firms is modelled and on parameter values, a new type of multiplicity of equilibria may arise. Finally, we study the implications of our model forthe skill-premium and we illustrate novel reasons for linking North-South trade tointellectual property rights protection.

The INTERNORM project : bridging two worlds of expert- and layknowledge in standardization

This paper presents a pilot project to reinforce participatory practices in standardization. The INTERNORM project is funded by the University of Lausanne, Switzerland. It aims to create an interactive knowledge center based on the sharing of academic skills and the experiences accumulated by the civil society, especially consumer associations, environmental associations and trade unions to strengthen the participatory process of standardization. The first objective of the project is action-oriented: INTERNORM provides a common knowledge pool supporting the participation of civil society actors to international standard-setting activities by bringing them together with academic experts in working groups and by providing logistic and financial support to their participation to meetings of national and international technical committees. The second objective of the project is analytical: the standardization action initiated through INTERNORM provides a research field for a better understanding of the participatory dynamics underpinning international standardization. The paper presents three incentives that explain civil society (non-)involvement in standardization that try to overcome conventional resource-based hypotheses: an operational incentive, related to the use of standards in the selective goods provided by associations to their membership; a thematic incentive, provided by the setting of priorities by strategic committees created in some standardization organization; a rhetorical incentive, related to the discursive resource that civil society concerns offers to the different stakeholders.