Primary mediastinal large B-cell lymphoma in HIV: report of two cases

Primary mediastinal large B cell lymphoma (PMLBCL) is a subtype of diffuse large B cell lymphoma arising in the mediastinum with distinctive clinical and morphological features. Though diffuse large B cell lymphoma is one of the most common non-Hodgkin lymphoma associated with AIDS, there are no data available regarding the association of HIV and PMLBCL. We report here two cases of PMLBCL arising in AIDS patients. In both cases, PMLBCL presented in a setting of low CD4 T-cell count as rapidly enlarging mediastinal mass. The morphologic and immunophenotypic findings are characteristic of PMLBCL. One of the two patients, a 25-year-old woman who had localized disease and evidence of Epstein–Barr virus in lymphoma cells, did not respond to chemotherapy and died of disease progression 5 months after diagnosis. The second patient, a 38-year-old male with disseminated disease, responded to therapy and is disease-free after 9 months of follow-up

MyD88-dependent autoimmune disease in Lyn-deficient mice

Recent evidence suggests that systemic autoimmune disease depends on signals from TLR ligands, but little is known about how TLR-dependent pathways lead to the loss of self tolerance in vivo. To address this, we have examined the role of TLR signaling in Lyn-deficient mice, which develop an autoimmune disease similar to SLE. We found that absence of the TLR signaling adaptor molecule MyD88 suppresses plasma cell differentiation of switched and unswitched B cells, and prevents the generation of antinuclear IgG antibodies and glomerulonephritis. In mixed chimeras the increased IgM and IgG antibody secretion in Lyn-deficient mice is at least partially due to B cell-independent effects of Lyn. We now show that MyD88 deficiency blocks the expansion and activation of DC in which Lyn is also normally expressed, and prevents the hypersecretion of proinflammatory cytokines IL-6 and IL-12 by Lyn-deficient DC. These findings further highlight the important role of TLR-dependent signals in both lymphocyte activation and autoimmune pathogenesis

MyD88-dependent autoimmune disease in Lyn-deficient mice.

Recent evidence suggests that systemic autoimmune disease depends on signals from TLR ligands, but little is known about how TLR-dependent pathways lead to the loss of self tolerance in vivo. To address this, we have examined the role of TLR signaling in Lyn-deficient mice, which develop an autoimmune disease similar to SLE. We found that absence of the TLR signaling adaptor molecule MyD88 suppresses plasma cell differentiation of switched and unswitched B cells, and prevents the generation of antinuclear IgG antibodies and glomerulonephritis. In mixed chimeras the increased IgM and IgG antibody secretion in Lyn-deficient mice is at least partially due to B cell-independent effects of Lyn. We now show that MyD88 deficiency blocks the expansion and activation of DC in which Lyn is also normally expressed, and prevents the hypersecretion of proinflammatory cytokines IL-6 and IL-12 by Lyn-deficient DC. These findings further highlight the important role of TLR-dependent signals in both lymphocyte activation and autoimmune pathogenesis.

Pine heartwood and glass surfaces: easy method to test the fate of bacterial contamination

Wooden surfaces in interior use hold potential for improving human health and wellbeing. The antibacterial properties of wood might reduce the possibility of cross-contamination from surfaces. In order to be able to control the hygienic quality of the wooden surface, the antibacterial effect should be better understood. The main aim of this thesis was to identify and evaluate the antibacterial properties of wood and its components.  Different methods were developed and used to study the antibacterial properties of Scots pine and Norway spruce, heartwood and sapwood. The solid wood surface showed clear antibacterial properties, even when the extractives had been removed with acetone. Studies with the extracts showed several human pathogens, including methicillin-resistant Staphylococcus aureus, to be susceptible to pine heartwood and sapwood in particular, and also, to some extent, spruce. Besides extractives, lignin was the only separate wood component showing antibacterial properties. Wood volatile organic compounds (VOCs), which were studied in gaseous form, showed an antibacterial effect against various human pathogens.  Several antibacterial compounds were found in all the extracts, however, they did not always explain the order of antibacterial activity between wood species. No single compound could alone explain the effect, hence the antibacterial effect derives either from different mechanisms in different species or from a synergistic effect. α-pinene and limonene could partly explain the antibacterial effect of the VOCs, but other components were also found to have an influence.  Wood was found to have various antibacterial parts and a diverse range of bacterial pathogens that were sensitive to it. These results offer a good ground for the exploitation of the hygienic properties of wood and a good starting point for enhancing them further. Additionally, the extracts showed promising qualities and they should be studied further in regard to resistant pathogens.Puupinnat sisätiloissa vaikuttavat positiivisesti ihmisten terveyteen ja hyvinvointiin. Puun antibakteeriset ominaisuudet saattavat vähentää pintojen kautta tapahtuvan kontaminaation todennäköisyyttä. Antibakteeristen ominaisuuksien parempi ymmärrys mahdollistaa puupintojen hygieenisen laadun paremman hallinnan. Tämän väitöskirjan päätavoite oli selvittää puun ja sen komponenttien antibakteerisia ominaisuuksia.  Männyn ja kuusen sydän- ja pintapuun antibakteerisuuden tutkimiseen käytettiin osin tätä työtä varten kehitettyjä menetelmiä. Puupinnan todettiin olevan antibakteerinen myös silloin, kun puun uuteaineet oli poistettu asetonilla. Uutteiden tarkempi tutkimus osoitti erityisesti männyn sydän- ja pintapuun, mutta jonkin verran myös kuusen uutteiden ehkäisevän useiden tautia aiheuttavien bakteereiden mm. metisilliinille resistentin Staphylococcus aureuksen (MRSA) kasvua. Uutteiden lisäksi ligniini oli ainoa erillinen komponentti, jolla todettiin antibakteerisia ominaisuuksia. Puusta haihtuvilla orgaanisilla yhdisteillä (VOC) todettiin antibakteerisia ominaisuuksia useita tautia aiheuttavia bakteerikantoja kohtaan.  Kaikissa uutteissa todettiin useita antibakteerisia yhdisteitä, mutta niiden määrä ei aina selittänyt eri puulajien antibakteerisuutta suhteessa toisiin puulajeihin. Mikään yksittäinen yhdiste ei yksin selittänyt antibakteerista vaikutusta, joten ilmiö johtuu joko eri puulajeilla eri mekanismeista tai synergisistä vaikutuksista. α-pineeni ja limoneeni selittivät osin VOCien antibakteerisia ominaisuuksia, mutta myös muilla yhdisteillä todettiin olevan vaikutusta.  Puun antibakteerisuuden todettiin johtuvan useista eri aineista ja tehoavan useisiin eri bakteereihin. Nämä tulokset tarjoavat hyvän lähtökohdan puun hygieenisten ominaisuuksien hyödyntämiseen ja niiden kehittämiseen. Uutteet osoittautuivat myös tehokkaiksi ja niiden ominaisuuksia erityisesti suhteessa resistentteihin bakteereihin kannattaisi tutkia lisää