Reticular fibroblasts in peripheral lymphoid organs identified by a monoclonal antibody.

peer reviewedWe have produced a panel of monoclonal antibodies directed against nonlymphoid cells in central and peripheral lymphoid organs. In this paper we present the reactivity of one of these antibodies, ER-TR7. This antibody detects reticular fibroblasts, which constitute the cellular framework of lymphoid and nonlymphoid organs and their products. In frozen sections of the spleen incubated with this antibody, the red pulp and white pulp are clearly delineated. Furthermore, the major white pulp compartments--the follicles and periarteriolar lymphoid sheath as well as the marginal zone--are recognized by their characteristic labeling patterns. In lymph nodes, the capsule, sinuses, follicles, paracortex, and medullary cords are clearly delineated. In the thymus and bone marrow no such specialized compartments were demonstrated. ER-TR7 reacts with an intracellular component of fibroblasts. Since ER-TR7 does not react with purified laminin, collagen types I-V, fibronectin, heparan sulfate proteoglycan, entactin, or nidogen, it detects a hitherto uncharacterized antigen. The possible role of the ER-TR7 positive reticular fibroblasts in the cellular organization of peripheral lymphoid organs will be discussed

Mechanical properties of some materials used in airplane construction

Since lightness is desirable in airplane construction, greater stresses must be tolerated than in other kinds of construction. It is therefore necessary to have a more accurate knowledge of the greatest stresses that may occur and of the actual properties of the materials used. The Aeronautic Research Laboratories took the limit of elasticity as the basis of the strength calculations. Many tests were made of different steels, woods, aluminum alloys, and fabrics

Protection of wooden airplane parts against moisture by means of varnish

The objects of the experiments herein described were to test the protection afforded by Valspar oil varnish against the absorption of moisture by wooden airplane parts and the consequent changes in their elastic properties and to compare some of the best Dutch varnishes with Valspar

Lymphoid Microenvironments in the Thymus and Lymph Node

The three-dimensional architecture of the thymus and mesenteric lymph node reveals several different stromal cell types important in the development and function of T cells. In the thymic cortex, T cells proliferate and differentiate in a meshwork of epithelial-reticular cells. They then migrate towards the medulla where they may interact with interdigitating cells. T cells migrate from the thymus through perivascular spaces, surrounding large vessels at the cortico-medullary boundary. In this area also large thymic cystic cavities are found, their function remains at present unclear. Mature selected T cells leave the thymus most probably by the venous bloodstream, to enter peripheral lymph nodes. Upon entering the lymph node they cross the wall of high endothelial venules. On the other hand, lymph enters the node by afferent lymphatics draining into various types of sinuses. Here, macrophages are strategically located to phagocytose and process antigen. These cells then expose antigen to T cells and B cells within the lymph node parenchyma, thus creating a microenvironment for the onset of an immune response. The various microenvironments important in T cell development and T cell function are shown in this paper using scanning electron microscopy as a dissecting tool. We discuss our morphological findings in the light of recent data on the physiology of T cell differentiation and function

Highly frequent infections with human rhinovirus in healthy young children: A longitudinal cohort study

AbstractBackgroundHuman rhinoviruses (HRVs) are an important cause of respiratory tract infections.ObjectivesWe questioned whether the high prevalence rates of HRVs found in epidemiological studies is due to long-term individual continuity or a result of frequent infections with different HRV subtypes.Study designIn a 6-month winter period 18 healthy controls, aged 0–7 years, were at least sampled every two weeks for HRV-PCR, irrespective of respiratory symptoms. All HRV positive samples were genotyped to determine HRV diversity.ResultsIn total 272 samples were collected. HRV was found in 101/272 (37%) samples. Genotyping revealed 27 different HRV subtypes. A median of 3.0 different HRV subtypes was found per child. Re-infections and continuity with identical HRV sequences were observed. The number of HRVs were higher in the youngest age group (p=0.01) and they had more different HRV subtypes (p=0.05) compared to oldest age group.ConclusionsWe found a high HRV exposition with a considerable diverse population of HRV subtypes in young children. These results have major implications for future research into the pathogenic role of HRV in respiratory diseases. Characterisation of subtypes will be necessary to discriminate between prolonged continuity and re-infections in patients with respiratory diseases

Measuring quality of life in Dutch people with aphasia: development and psychometric evaluation of the SAQOL-39NL

Background: Cross-cultural adaptation of health-related quality of life (HRQL) scales is useful as it allows comparisons of therapy outcomes across different countries to be drawn. Aims: To adapt the English Stroke and Aphasia Quality of Life—39 item generic stroke scale (SAQOL-39g) into Dutch. To investigate the psychometric properties (acceptability, internal consistency, test–retest reliability and construct validity) of the Dutch version (SAQOL-39NL). Methods & Procedures: Established guidelines for cross-cultural adaptation of self-report measures were followed. Individuals with chronic aphasia were recruited from six centres in The Netherlands. Participants completed the SAQOL-39NL and a visual analogue scale on HRQL in an interview format with an aphasia specialist speech and language therapist. Outcomes & Results: The cross cultural adaptation resulted in a consensus version of the SAQOL-39NL, which participants (n = 13) felt was informative and of value in assessing the impact of stroke on their lives. The SAQOL-39NL was acceptable (no missing data; no floor or ceiling effects) to people with chronic aphasia (n = 47). Internal consistency (Cronbach’s alpha = 0.89 for scale; 0.84–0.91 for domains) and test–retest reliability were excellent (ICC = 0.90 for scale, 0.70–0.93 for domains). Internal validity (moderate intercorrelations between domains) and convergent validity (r = 0.45) were good. Conclusions: The SAQOL-39NL is a psychometrically sound measure of HRQL for Dutch speaking people with aphasia. As is common with new measures, its psychometric properties need to be evaluated further; and its appropriateness as a clinical outcome measure needs to be determined. Yet, the SAQOL-39NL is a promising new measure for use in clinical practice, audit and research