Fos-immunoreactive responses in inferior colliculi of rats with experimental audiogenic seizure susceptibility

Quantitative ultrasound (QUS) is a simple, inexpensive and non-invasive measure of bone which has been used in research settings for the prediction of osteoporosis. This review summarizes the current status of the epidemiology of QUS analysis, including its relationship with bone mineral density (BMD), risk of osteoporotic fracture and risk factors for osteoporosis. Although only moderately correlated with BMD, QUS appears to be as strong a predictor of osteoporotic fracture as BMD and may predict fracture independent of BMD. Risk factors for low QUS, including age, menopause, body composition and physical inactivity, seem to parallel those of low BMD. More longitudinal research is needed to confirm the clinical utility of QUS and more experimental and population-based studies are needed to determine whether the etiology of low QUS values is different from that of low bone mass.     

Hyperacute lung rejection in a pig-to-human transplant model: the role of anti-pig antibody and complement

BACKGROUND: The physiology of hyperacute rejection of pig lung by human blood and the role of antispecies antibody and complement in this phenomenon have not previously been characterized. METHODS: Human blood was perfused through an ex vivo pig heart-lung preparation. In the treatment groups, blood was either unmodified or modified to deplete alternative pathway complement (heat treatment), anti-pig antibody, or both. Control experiments were performed with unmodified and heat-treated pig blood. Physiologic parameters, organ survival, and immunohistology were the primary outcome measures assessed. RESULTS: Pig lung was consistently damaged by human blood within 45 min (median 20 min), as evidenced by elevated pulmonary vascular resistance and parenchymal injury. Immunohistologic studies of perfused lungs showed prominent deposition of IgM and classical pathway component, C4, and weaker deposition of alternative pathway component, properdin. Heat treatment did not impede the rise in pulmonary vascular resistance or significantly prolong survival. Depletion of anti-pig antibody prolonged survival (median 90 min) and attenuated the rise in pulmonary vascular resistance. Antibody absorption, combined with heat treatment of plasma, prevented the elevation in pulmonary vascular resistance and yielded median graft survival (210 min) similar to pig blood perfusion (approximately 240 min). CONCLUSIONS: These results show that elevated pulmonary vascular resistance and pulmonary parenchymal injury are mediated at least in part by antispecies antibody and heat-sensitive pathways. They are consistent with the hypothesis that complement activation contributes significantly to acute lung damage in the pig-to-human species combination.     

Ensuring Trust, Privacy, and Etiquette in Web 2.0 Applications

An analysis of three user studies of Web 2.0 applications reveals the most important requirements related to ethical issues. The development of features that support these requirements should be tailored to the type of application and specific community needs.     

Dew Chemistry and Acid Deposition in Glendora,California, During the 1986 Carbonaceous Species Methods Comparison Study

Dew was collected and analyzed during the Carbonaceous Species Methods Comparison Study in the Los Angeles basin (Glendora, CA) in August 1986. Formate, acetate, and other carboxylate anions were consistently observed, with formate generally being the most abundant anion in the dew. These carboxylate anions appear to be attributable to deposition of carboxylic acids from the ambient air. Free acid (H⁺) was only about one-fifth of the total dew acidity; carboxylic acids could have accounted for half of the remainder. The H⁺ concentrations were far lower than in dew in the northeast United States (respective pH averages 4.7 and 4.0). Whereas dew in the Northeast was essentially a dilute HNO₃/ H₂SO₄ mixture, that in Glendora contained substantial amounts of many other inorganic species. S(IV) in the dew in Glendora was stable against oxidation, even by H₂O₂, probably signifying formation of the bisulfite adduct with formaldehyde (considerable amounts of formaldehyde and acetaldehyde were present), in contrast to the S(IV) behavior in dew in the Northeast. The Glendora dew results are consistent with 1985 observations in Claremont, 17 km away. Dew appears to play only a minor role in the acid deposition budget in the Los Angeles basin. Daytime dry deposition of HNO₃(g) (and possibly of carboxylic acids) is far more important. In turn, dry deposition appears to be far more important than rainfall in the acid deposition budget of the Los Angeles basin, which yet is probably far smaller per unit surface area than in parts of the Northeast.     

High incidence of relapse after autologous stem-cell transplantation for B-cell chronic lymphocytic leukemia or small lymphocytic lymphoma

BACKGROUND: High-dose therapy followed by autologous stem-cell transplantation (autoSCT) induces complete remissions in the majority of patients with advanced B-cell chronic lymphocytic leukemia or small lymphocytic lymphoma (B-CLL). However, the long-term utility of this therapy for B-CLL is unknown. PATIENTS AND METHODS: Sixteen previously treated patients with B-CLL were transplanted using autologous blood (n = 13) or bone marrow (n = 3). The median age of the patients was 49 f1p4s (range 44-60 years), and the median number of prior chemotherapy regimens was two. Patients were eligible for transplantation if they had chemosensitive disease and no morphologic evidence of malignant cells in the graft. Preparative regimens included cyclophosphamide and total-body-irradiation, with or without cytarabine, or BEAC. RESULTS: All patients engrafted and achieved a complete remission posttransplant. Ten patients were alive at a median of 41 months (range 22-125 months), and five were disease-free. Eight patients have relapsed and six have died (three from progressive malignancy). The projected three-year overall survival, failure-free survival and relapse rates were 68%, 37%, and 56%, respectively. CONCLUSIONS: AutoSCT for advanced B-CLL is associated with a high relapse rate. Whether this therapy can prolong life or produce cures is uncertain.     

Cytochemical demonstration of sites of hydrogen peroxide generation and increased vascular permeability in isolated pig hearts after ischaemia and reperfusion

Isolated pig hearts, subsequently perfused with pig or human blood, were prepared for the cytochemical demonstration of sites of hydrogen peroxide generation and increased vascular permeability. Oxidant stress was associated with ultrastructural changes commonly seen following myocardial reperfusion. In addition, the precipitation of cerium perhydroxide following perfusion with physiological saline containing cerium chloride suggested the vascular endothelium and leukocytes as sources of oxidants. This was associated with rapid penetration of horseradish peroxidase through the intercellular clefts of the vascular endothelium into the interstitial space, suggesting increased vascular leakiness at these sites. The rapid penetration of horseradish peroxidase was observed at all monitored periods of reperfusion with pig or human blood. This indicates that the increased permeability occurred during the ischaemic period and continued during reperfusion. Morphological damage was greatest in pig hearts reperfused with whole human blood and this was attenuated if the blood was preabsorbed to remove antibodies prior to reperfusion. We conclude that oxidant stress was initiated during ischaemia and continued during reperfusion in this model.