Alveolar soft-part sarcoma: evidence for its myogenic origin and for the involvement of 17q25

A typical case of alveolar soft-part sarcoma was examined using ultrastructural, immunohistochemical and cytogenetic methods. Immunohistochemical stains were performed on frozen sections and showed strong desmin expression with the three anti-desmin antibodies used. In addition, the tumour cells were weakly positive for vimentin and myosin. Neural markers were negative. Chromosomal analysis showed consistent involvement of 17q25—an abnormality which has been reported in another alveolar soft-part sarcoma. The histogenesis of alveolar soft-part sarcoma is still debatable but our findings support a myogenic origin. The finding of an apparently identical chromosomal abnormality in two of three thus far examined cases of alveolar soft-part sarcoma is of interest and must await further confirmation, but it may result in the identification of a chromosomal marker for this enigmatic tumour and thus pave the way for further molecular elucidation.     

Occupational allergy to bumble bee venom

The clinical profile of anaphylactic reactions to bumble bees is described and successful immunotherapy with honey bee venom in seven bumble bee allergic patients is reported. The cause of the high frequency of sensitization to pollen in these patients is discussed.     

Characteristics of Immune Responses to Native and Protein Conjugated Pneumococcal Polysaccharide Type 14

The immune response to pneumococcal polysaccharide type 14 (PPS-14), induced by native PPS-14 was compared with the response induced by PPS-14 conjugated with CRM₁₉₇ (PPS-14-CRM₁₉₇). In our animal model, immunization with PPS-14-CRM₁₉₇ gave a significant enhancement of anti-PPS-14 serum titres for IgM and IgG. but not for IgA. Also an increase in total number of anti-PPS-14 antibody-secreting ceils was found. Using immunohistochemical techniques, a different distribution pattern of specific antibody-containing cells in spleen section after immunization with PPS-I4-CRM₁₉₇ was observed. Furthermore, a higher number of IFN-γ producing cells was found after immunization with PPS-14-CRM₁₉₇, as compared with immunization with PPS-14. This enhanced IFN-γ production may be the cause for enhanced IgG response observed after immunization with PPS-14-CRM₁₉₇.
The specific immune response was less affected by splenectomy in animals immunized with PPS-14-CRM₁₉₇ than with PPS-14. However, an age-related response to the native as well as the conjugated form of the PPS-14 was observed, since no effect of conjugation with CRM₁₉₇ was seen in the onset of the immune response to PPS-14 in young animals.
In conclusion, our results affirm the hypothesis that conjugation of polysaccharides changes the characteristics of the antigen towards a thymus-dependent antigen.     

Incomplete septal cirrhosis: histopathological aspects

We have reviewed 60 liver specimens from 47 patients with the diagnosis of incomplete septal cirrhosis observed between 1968 and 1987. In reaching this diagnosis evaluation of the following histological features appeared to be helpful: parenchymal nodularity, thin incomplete septa, hypoplastic portal tracts, increased number of venous channels, abnormal spacing between portal tracts and veins, crowding of reticulin fibres between adjacent zones of hyperplastic parenchyma, hyperplasia of hepatocytes and dilated sinusoids. These histological features were not specific for incomplete septal cirrhosis as they were also present--although less evident and less frequent--in a series of 87 non-cirrhotic liver specimens. Reticulin stains were an essential adjunct to assess the architectural disturbance, which was often inconspicuous in needle biopsies. Histological features indicating a specific aetiology were lacking in the great majority of cases. On histological and clinical grounds, incomplete septal cirrhosis resembles idiopathic portal hypertension, nodular regenerative hyperplasia and partial nodular transformation; in these entities an obliterative portal venopathy with non-uniformity of portal blood supply to the parenchyma has been suggested as a pathogenic mechanism. In the present study phlebosclerotic lesions of the portal vein were found in only two cases. This might be explained by sampling error or, alternatively, the hypoplastic portal tracts observed might be a functional equivalent of obliterative portal venopathy resulting in a deficient portal blood supply. Non-uniformity of blood supply to the parenchyma may explain the similarities between incomplete septal cirrhosis and the diseases mentioned.     

T Cell-Mediated Production of Tumour Necrosis Factor-α by Monocytes

The aim of this study was to examine the tumour necrosis factor (TNF)-alpha production by peripheral blood mononuclear cells activated by mitogens. Considerable amounts of TNF-alpha, ranging from 1.0 to 5.0 ng/ml, were present in the supernatants of cultures of human peripheral blood mononuclear cells (PBMC), stimulated with either the anti-CD3 monoclonal antibody OKT3 or the lectin phytohaemagglutinin (PHA). The amount of TNF-alpha secreted in the supernatant was closely correlated to the degree of T cell proliferation in such cultures, as measured by [3H]TdR incorporation. In the absence of proliferating T cells the mitogens did not induce secretion of TNF-alpha by monocytes. Supernatants of proliferating T cells were shown to induce TNF-alpha production by monocytes. The macrophage-activating factor gamma interferon (IFN-gamma) was also shown to induce, in the absence of endotoxin, TNF-alpha secretion by monocytes in a dose-dependent manner. The induction of TNF-alpha production by supernatants of proliferating T cells could largely be abrogated by passaging the supernatants on an anti-IFN-gamma column before adding them to the monocytes. It is therefore concluded from this study that the production of TNF-alpha by monocytes can be induced by proliferating T cells and that this induction can largely be attributed to the T cell lymphokine IFN-gamma.     

Effects of light exposure and sleep displacement on dim light melatonin onset

The purpose of the study was to induce in two different ways, a phase-angle difference between the circadian pacemaker and the imposed sleep-wake cycle in humans, we intended to: (i) shift the circadian pacemaker by exposure to bright light and keep the timing of the sleep-wake cycle fixed; and (ii) keep the timing of the circadian pacemaker fixed by a constant light-dark cycle and displace sleep. We monitored dim light melatonin onset (DLMO), core body temperature and sleep. DLMO was delayed significantly after 3 days of a 3-h delayed sleep-phase when compared with 3 days of sleep at a normal or 3-h advanced sleep-phase. The shifts in DLMO were not accompanied by shifts in body temperature, changes in waking-up time or by a change in the duration of the first rapid eye movement (REM) sleep episode. Three days of light exposure in the morning or evening resulted in shifts in DLMO of similar magnitude, but this was accompanied by shifts in the rhythm of body temperature, changes in waking-up time and in the duration of the first REM sleep episode. We conclude that the changes observed after light exposure reflect shifts in the circadian pacemaker. In contrast, we propose that the changes observed in DLMO after sleep displacement are not mediated by the circadian pacemaker. These results raise some doubts about the reliability of DLMO as a marker of circadian phase in cases of sleep disturbances. Finally, we initiate a search for changes in sleep that might be responsible for the unexpected effects on DLMO.     

Expression of Melan-A in Spitz,Pigmented Spindle Cell Nevi,and Congenital Nevi: Comparative Immunohistochemical Study

The expression of the antibody Melan-A in 27 benign melanocytic skin lesions (10 congenital nevi, 10 Spitz nevi, and 7 pigmented spindle cell nevi) was compared to that of S100 protein and HMB-45. To evaluate the role of Melan-A in differentiating melanocytic and nonmelanocytic lesions we assessed a number of benign nonmelanocytic skin lesions including neurofibromas, granular cell tumors, and dermatofibromas. Melan-A had an identical staining pattern to S100 protein in the melanocyte population of all lesions, but had the advantage of only staining cells of melanocytic lineage and no other cell types. HMB-45, although staining the junctional components of all lesions with a junctional component, showed varied intensity and distribution in the dermal components. Melan-A is much cleaner than S100 protein, having no background staining, and in skin appears to be specific for melanocytes. The nonmelanocytic lesions did not express Melan-A.     

Access to health and social services for IDU: The impact of a medically supervised injection facility

Introduction and Aims. Injection drug users (IDU) often experience barriers to conventional health‐care services, and consequently might rely on acute and emergency services. This study sought to investigate IDU perspectives regarding the impact of supervised injection facility (SIF) use on access to health‐care services. Design and Methods. Semi‐structured qualitative interviews were conducted with 50 Vancouver‐based IDU participating in the Scientific Evaluation of Supervised Injecting cohort. Audio‐recorded interviews elicited IDU perspectives regarding the impact of SIF use on access to health and social services. Interviews were transcribed verbatim and a thematic analysis was conducted. Results. Fifty IDU, including 21 women, participated in this study. IDU narratives indicate that the SIF serves to facilitate access to health care by providing much‐needed care on‐site and connects IDU to external services through referrals. Participants’ perspectives suggest that the SIF has facilitated increased uptake of health and social services among IDU. Discussion and Conclusions. Although challenges related to access to care remain in many settings, SIF have potential to promote health by facilitating enhanced access to health‐care and social services through a model of care that is accessible to high‐risk IDU.[Small W, Van Borek N, Fairbairn N, Wood E, Kerr T. Access to health and social services for IDU: The impact of a medically supervised injection facility. Drug Alcohol Rev 2009;28:341–346]