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The purpose of this investigation was to describe the adult well sibling's experience of having grown up with a sibling who has insulin-dependent diabetes mellitus (IDDM). Using existential-phenomenological interview procedures, 14 participants were asked what it was like to have a chronically ill sibling. Analysis of participants' experiences was done using a hermeneutical approach. The thematic description of the experience of having lived with a chronically ill sibling with IDDM was divided into two interdependent and interrelated periods, the past and the present. The metaphor of a protective shield woven around the diabetic sibling by his or her family was taken from the words of a participant, and is seen by participants as occurring in the past and the present. The themes of the past provide the background for the themes of the present. Many of the themes of the past are moved forward to the present, but, because of the passage of time, are described differently by participants. Results of this study reinforce the fact that the stressors of chronic illness affect all family members, including the well siblings. It is imperative that nurses give care to the family, not just the designated patient. Nurses must be prepared to provide counseling, education, and anticipatory guidance to adults who have a sibling with a chronic illness.

Proton spectroscopic imaging at short TEs (20-30 ms) in human brain requires volume preselection inside the brain to suppress overwhelming lipid and water signals from surrounding tissue. In this article we discuss limitations of conventional volume preselection using stimulated echoes that lead to spectral contamination from surrounding tissue. Improved volume preselection was obtained by adding a complete outer volume suppression (presaturation). The performance of the method is illustrated on normal volunteers and on clinical cases with brain tumors and multiple sclerosis (MS) plaques. In normal human brain, we detected resonances with short T2 values and complex J-coupling, including rather broad methyl/methylene resonances in the chemical shift range between 0 and 2 ppm. Spectroscopic images obtained on patients with intracranial tumors and on one patient with several MS plaques demonstrate the possibility of detecting regional distributions of increased methyl/methylene resonances between 0 and 2 ppm in brain lesions.

By exploiting congenic rat strains (HO.B2 and PVG/c) cell-mediated immune responses against Ag-B antigens alone were measured and compared with responses against (1) non-Ag-B antigens and (2) Ag-B and non-Ag-B antigens in combination. It was confirmed that multiple non-Ag-B antigens provoke prompt first-set skin graft rejections, but are much weaker than Ag-B antigens in stimulating both graft-versus-host (GVH) and cytotoxic activity. No evidence of synergistic interaction was found between anti-Ag-B and anti-non-Ag-B responses either by GVH assay or in the generation of cytotoxic cells. Specific partitioning of cytotoxic cells on antigenic monolayers suggested that cytotoxic cells on antigenic monolayers suggested that cytotoxicity is predominantly directed against Ag-B antigens. The measurements of GVH activity consolidate previous work, which suggested that 4.5 to 12% of nonimmune T cells can respond to each Ag-B determined antigenic complex and eliminate the possibility that most of these cells were responding to non-Ag-B antigens. Two principles for measuring GVH activity were compared: (1) 3H-thymidine incorporation into donor lymphocytes at 24 hr after transfer to irradiated F1 hybrid recipients and (2) the popliteal lymph node assay, which depends on a secondary phase of host cell proliferation.

In an investigation into the effect of short-term exposure to different temperatures and humidities on the sebaceous glands of Ayrshire calves it was concluded that temperature had no appreciable effect on sebum output or its fatty acid composition. At a low humidity, however, the cutaneous outputs of palmitic and myristic acids were higher. On prolonged exposure to a warm environment, a higher output of sebum occurred together with an increase in the percentage of linoleic acid in the sebum.

Lymphocytes were exposed in vitro to either trypsin or neuraminidase. The ability of the treated cells to migrate into tissues were measured (a) by i.v. injection into intact recipients and (b) by vascular perfusion through an isolated lymph-node preparation. The localization of trypsinized cells in the lymph-nodes of recipients was deficient when compared to untreated lymphocytes and there was a surplus of trypsinized cells in blood. Trypsinized cells migrated into the isolated nodes in reduced numbers. By contrast, neuraminidase treated lymphocytes were markedly deficient in the blood of recipients early after injection; their localization in the spleen and lymph-nodes was also deficient but they were in surplus in the liver. Moreover they migrated into the isolated nodes in slightly increased numbers. By 24 hr after injection the perturbed localization pattern produced by either enzyme was partly restored to normal. In conclusion, tryspin interfered with the capacity of lymphocytes to migrate into lymph-nodes but neuraminidase did not; the latter promoted the hepatic sequestration of cells and the reduced localization in the blood and tissues was a consequence of this. The hypothesis that lymphocytes adhere to specialized endothelia in lymph-nodes because of specific glycoside sequences on their surface lacks experimental support.

Radioactively labelled rat lymphocytes were treated in vitro with concanavalin A (con A) and injected intravenously into syngeneic recipients. By examining the blood and tissues at intervals from 30 min to 48 h after injection, it was confirmed that con A altered the distribution of lymphocytes. Comparison was made with the localization of alternatively labelled untreated lymphocytes injected into the same recipients and with untreated lymphocytes injected into other recipients. Within 1 h of injection there was a surplus of treated cells in the lungs and liver and deficits (of equal magnitude) in the blood, spleen and lymphnodes. By 24 h after injection there was a twofold surplus of treated cells in the spleen but a persisting deficit in lymphnodes. These perturbations can be ascribed to the prolonged retention of lymphocytes in normal sites of localization; there is no evidence that con A either hinders the migration of lymphocytes from the blood or diverts them to abnormal sites. It is not clear whether the delay in the recipients’ tissues requires an active response to con A but, if so, then it does not proceed to blastic transformation.

Two experiments are described concerned with the mechanism of host cell activation in the rat popliteal lymph node (LN) undergoing a graft-versus-host (GVH) reaction. (1) Irradiated, F1 hybrid hosts (750 rad) mounted an impaired response to parental strain T cells. This was augmented by an intravenous injection of F1 hybrid lymphocytes but not by parental strain B lymphocytes syngeneic with the initiating T cells. When the donor T cells (footpad) and B lymphocytes (intravenous) were completely allogeneic the residual response of the irradiated F1 was completely inhibited. (2) The popliteal LN response in the semi-allogeneic situation of the type (A x C)F1 leads to (B x C)F1 was, if anything, weaker than in the allogeneic situation AA leads to BB. These results and other data are discussed in terms of a possible major histocompatibility complex (MHC) requirement for host cell activation. The sharing of an MHC haplotype between donor and host cells is unlikely to be a necessary or sufficient condition for host cell activation.

The lymph nodes (LN) of the congenitally athymic nude rat(rnu) were compared with the LN of non-nude littermates. The mesenteric and coeliac LN were smaller in the rnu rats, but the axillary and the cervical LN were larger. Germinal centres were found in the LN of nude rats. They were scarce and often very small, but some were of normal structure, especially in the cervical LN. The endothelium of post-capillary venules in the LN or normal rats, was seen. The paracortex was extremely depleted of lymphocytes but remained a distinct area occupied predominantly by pale interdigitating cells. In some LN the medullary sinuses were distended and the cords engorged with plasma cells. The predominant cells in thoracic duct lymph were immunoglobulin-positive B lymphocytes. The hourly output of these cells was the same as that in non-nude littermates. However, small numbers of thoracic duct cells were positive for the markers identified by the monoclonal antibodies W3/13 and W3/25, although in normal rats these are not expressed on small B lymphocytes.

Thoracic duct lymphocytes (TDL) from normal rats will restore a primary antibody response to sheep erythrocytes (SRBC) in irradiated recipients and cause a graft-versus-host reaction in F1 hybrid rats; lymphocytes from rats immunized with either tetanus toxoid or dinitrophenylated bovine gamma globulin (DNP BGG) will generate specific antibody after cell transfer and challenge. The ability of TDL to mediate each of these responses is severely depressed by giving a single intravenous dose of the specific antigen shortly before cannulation of the thoracic duct, although the lymphocyte donors themselves respond normally. The injection of antigen does not decrease the output of lymphocytes in the thoracic duct and the effect is specific for the antigen injected. The findings are most readily accounted for by assuming that small subpopulations of specific lymphocytes are selected from the recirculating pool by antigen which has localized in lymphoid tissue. The observation that passive antibody abolishes selection by SRBC supports this interpretation. The strong selection exerted by a subcutaneous injection of SRBC in Freund's complete adjuvant, which induces delayed hypersensitivity but little early antibody, suggests that a common cell type may be involved in the induction of both delayed hypersensitivity and antibody formation. The anti-DNP antibody response generated by TDL from rats immunized with DNP BGG was abolished by a selecting injection of the homologous conjugate. The response was depressed to a smaller degree by injections of either BGG or dinitrophenylated human serum albumin, suggesting that carrier-specific (T) and hapten-specific (B) lymphocytes could be separately selected from the recirculating pool. The regional selection of recirculating lymphocytes by antigen may explain a number of phenomena in which the prior injection of antigen has been found to inhibit a subsequent immune response.

Fungi play integral roles in soil nutrient cycling, but the determinants of fungal diversity and biogeographic patterns of key functional groups remain poorly understood. By using pyrosequencing data from hundreds of globally distributed soil samples, we demonstrated fungal diversity that expands upon the taxonomic and molecular diversity recorded so far. Except for ectomycorrhizal symbionts, fungal functional group richness was unrelated to plant diversity and plant-to-fungus richness ratio declined exponentially towards the poles. Climatic factors, followed by edaphic and spatial variables, constituted the best predictors of fungal richness and community composition at the global scale. Fungi follow general biogeographic patterns and latitudinal diversity gradients with several exceptions. Fil: Tedersoo, Leho. University Of Tartu.; Estonia Fil: Bahram, Mohammad. University Of Tartu.; Estonia Fil: Põlme, Sergei. University Of Tartu.; Estonia Fil: Kõljalg, Urmas. University Of Tartu.; Estonia Fil: Yorou, Nourou. Université de Parakou. Faculté d′Agronomie; Benín Fil: Nouhra, Eduardo Ramon. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Greslebin, Alina Gabriela. Universidad Nacional de la Patagonia; Argentina Fil: Kohout, Petr. University Of Tartu.; Estonia Fil: Hosaka, Kentaro. National Museum of Nature and Science. Department of Botany; Japón Fil: Hiiesalu, Indrek. University Of Tartu.; Estonia Fil: Henkel, Terry W.. Humboldt State University. Department of Biological Sciences; Estados Unidos Fil: Harend, Helery. University Of Tartu.; Estonia Fil: Guo, Liang-dong. Chinese Academy of Sciences. Institute of Microbiology. State Key Laboratory of Mycology; China Fil: Geml, József. Fil: Grelet, Gwen. Landcare Research. Ecosystems and Global Change Team; Nueva Zelanda Fil: Gates, Genevieve. Tasmanian Institute of Agriculture; Australia Fil: Dunstan, William. Murdoch University. School of Veterinary and Life Sciences; Australia Fil: Dunk, Chris. Swedish University of Agricultural Sciences. Department of Forest Ecology and Management; Suecia Fil: Drenkhan, Rein. Estonian University of Life Sciences. Institute of Forestry and Rural Engineering; Estonia Fil: Dearnaley, John. University of Southern Queensland. Faculty of Health, Engineering and Sciences; Australia Fil: De Kesel, André. Botanic Garden Meise; Bélgica Fil: Dang,Tan. Vietnamese Academy of Forest Sciences; Vietnam Fil: Chen, Xin. Zhejiag University. College of Life Sciences; China Fil: Buegger, Franz. Helmholtz Zentrum München. Institute of Soil Ecology; Alemania Fil: Brearley, Francis Q.. Manchester Metropolitan University. School of Science and the Environment; Reino Unido Fil: Bonito, Gregory. Royal Botanic Gardens Melbourne; Australia Fil: Anslan, Sten. University Of Tartu.; Estonia Fil: Abell, Sandra. James Cook University. School of Marine and Tropical Biology; Australia Fil: Abarenkov, Kessy. University Of Tartu.; Estonia