Increasing case numbers of adenovirus conjunctivitis in Germany, 2010.

In 2010 (as of 13 October 2010), the number of adenovirus conjunctivitis cases reported to the Robert Koch Institute in Berlin, Germany, has increased by more than 250% compared with same period in the previous two years. An investigation was initiated to identify spatial or temporal clusters, possible sources of infection and potential connections to cases abroad. The analysis did not show a disproportionately affected sex or age group, but many infections were preceded by exposure to ophthalmological facilities, communal facilities or public places.

Validation of computer-mediated open-ended standardized patient assessments.

Quantitative information regarding the development of students' clinical reasoning skills is valuable in assessing third- and fourth-year medical students' clinical knowledge. Standardized patient cases are often used to obtain this quantified information. These cases typically involve a post-patient examination consisting of a series of closed-ended multiple-choice questions. Many medical educators question whether the results from the closed-ended multiple-choice questions truly reflect students' clinical knowledge and reasoning proficiency. Since 1995, the Kirksville College of Osteopathic Medicine (KCOM) has used a computer program, SOAP Note Plus, for standardized patient assessment of students to automate the post-encounter documentation and evaluation. This paper describes the development of the SOAP Note Plus program and a validation study which was conducted to determine the empirical association between the computer-mediated closed-ended and open-ended post-encounter standardized patient assessments. Correlation and GENOVA statistics were used in the analysis of the performance of third-year medical students on the closed-ended and the open-ended assessments following standardized patient encounters and the relationship to their undergraduate GPA, first 2-year medical school GPA and the actual clinical rotation evaluations. The initial results show the positive relationship between the open-ended assessment and the actual clinical rotation evaluations. undergraduate GPA and the first two-years of medical school GPA.

The interaction of cryoimmunoglobulins with a model surface.

Cryoimmunoglobulins are associated with numerous clinical problems ranging from collagen vascular disorders (rheumatoid arthritis and systemic lupus erythematosus) to infectious processes including HIV infection. The precise role of cryoglobulins in the pathophysiology of these disorders remains unresolved. Although cold insolubility may account for some of the observed processes, it cannot explain the entire array of findings in cryoglobulinemia. An alternative hypothesis suggests that the subtle differences responsible for cold precipitation of these proteins renders them intrinsically more sticky, resulting in deposition of cryoimmunoglobulins on vascular surfaces. We have explored this hypothesis by characterizing the binding of monoclonal cold soluble and cryoimmunoglobulins to silica beads as a model biological surface. It is found that monoclonal, type I, IgM and IgG cryoglobulins have only a slight tendency to bind to a greater extent to this surface than cold soluble immunoglobulins. Physical studies utilizing front surface fluorescence measurements and differential scanning calorimetry show surface interaction leads to partial thermal destabilization of the proteins. To a limited extent, this destabilization is more pronounced with the cryoglobulins compared to cold-soluble control homologues. Surface bound IgM cryoimmunoglobulin was also found to fix complement less efficiently than their cold soluble surface bound counterparts. These studies do not strongly support the hypothesis that pathological mechanisms of cryoimmunoglobulins primarily involve abnormal surface interactions, although surface effects could play a limited role in some situations.

Lack of binding between cryoimmunoglobulins, immunoglobulins and fibronectin: implications for immune complex vasculitis.

Immune-complex-mediated vasculitis is a frequent complication of rheumatoid arthritis and systemic lupus erythematosus. The mechanism of deposition of immune complexes within the vessel wall in these diseases remains unknown, but probably involves other proteins. Fibronectin is a likely candidate since it possesses the ability to bind to collagen, endothelial cells, and possibly immunoglobulins and immune complexes. In this study, the binding of fibronectin to IgG and IgM cryoglobulins, cold soluble IgM, IgG, IgG subclasses and IgG fragments was investigated in the solution phase. Static light scattering, fluorescence anisotropy, fluorescence intensity, and PEG precipitation studies were used to investigate binding under different conditions of temperature and ionic strength. These studies failed to demonstrate significant binding between fibronectin and IgM, IgG, IgG subclasses and IgG fragments under the conditions studied. These findings argue against solution phase binding of fibronectin and immunoglobulins contributing to immune complex vasculitis. The possibility of important surface interactions between these proteins has not been ruled out.

Washout of the pig liver with Haemaccel after hypothermic preservation.

In hepatic preservation by simple perfusion and hypothermic storage, a portal and hepatic washout before revascularization would avoid receptor hyperkaliema. In this report we study the effectiveness of this washout with Haemaccel at room temperature. Large-White pigs were used and eight livers were perfused "in situ" via the portal wein with Hartmann's solution containing 10,000 IU of heparin at 4 degrees C, and afterwards, via portal and arterial routes with C2 solution at 4 degrees C. After a cold ischemia time of less than 31/2 hours a liver washout via the portal vein and hepatic artery with Haemaccel before portal revascularization was done. The high concentrations of glucose, K+, GOT, GPT and LDH in the effluents obtained during the washout are attributed to Haemaccel hyperosmolarity. A portal and arterial hepatic washout associated with free drainage of the first 50-100 ml of portal venous blood after hepatic portal revascularization through the infrahepatic inferior vena cava (IH-IVC), prevents hyperkaliemia from occurring after a portal and arterial revascularization in the orthotopic liver transplant (OLT) in pigs.

[Immunosuppression with cyclosporin after orthoptic liver transplant in pigs]. / Immunosupresión con ciclosporina postrasplante ortotópico de hígado en el cerdo.

The immunosuppressive effect of cyclosporine A (CsA) was studied in six pigs that underwent orthotopic liver transplant (OLT). The drug was administered i.v. in low doses (1.5-4 mg/Kg-1/12 h-1) and associated with wide spectrum antibiotics. The mean survival of the animals was 23.4 +/- 11.2 days. All animals had fever, jaundice and hypertrichosis, and the preoperative corporal weight remained constant. Liver abscesses by E. coli were common autopsy findings. Livers also presented biliary regeneration and cholestasis with a slight lymphocytic infiltration. OLT in pigs without immunosuppressive treatment causes and elevation in serum gamma-GTP, GOT, LDH, alkaline phosphatase and bilirubin. In the post-mortem findings, the livers did not present abscesses but evidenced intense atrophy with hepatocellular necrosis and abundant lymphocytic infiltration.

Electrostatic properties of cryoimmunoglobulins.

Inhibition of the cryoprecipitation of cryoimmunoglobulins by neutral salts suggests that intermolecular electrostatic (charge-charge) interactions are responsible for their abnormal solution properties. To test this hypothesis, H+ titration curves and isoelectric points were measured for two monoclonal IgG cryoglobulins (Ger and Muk) and compared with four normal (cold soluble) monoclonal IgG. The cryoglobulin Ger manifested values outside the range encountered for the other proteins. The partitioning of the IgG proteins was also examined in aqueous polyethylene glycol-dextran two-phase systems in the presence of both positive and negative salt-induced electrostatic potentials across the phase interface. Both cryoglobulins were found to behave as if they were more negatively charged than the noncryoglobulins. The experiments support the hypothesis that the differences in solubility behavior of monoclonal cryoglobulin and noncryoglobulin proteins are caused by differences in the electrostatic properties of the proteins.

Kinetics of the precipitation of cryoimmunoglobulins.

The kinetics of the cryoprecipitation of two monoclonal IgG and two monoclonal IgM cryoimmunoglobulins, two IgM/IgG mixed cryoglobulins and a series of cold soluble monoclonal IgG and IgM immunoglobulins in the presence of polyethylene glycol have been compared by time dependent turbidity measurements. The effects of temp and ionic strength on kinetic processes are described in detail. The monoclonal cryoimmunoglobulins display lag times which are not seen with the other proteins, suggesting a critical nucleation event. The protein concn dependence of the lag times indicate that these nucleation centers contain only a few immunoglobulin molecules. Direct evidence for the existence of precipitation nuclei was obtained from dynamic light scattering studies of two of the monoclonal proteins during their lag periods. Both proteins manifested an approx. 20% decrease in their mean diffusion coefficients (corresponding to a 25% increase in Stokes' radius) prior to detectable precipitation. This suggests the formation of nuclei between 2 and 8 times the size of the monomeric proteins. It is postulated that the increasing size of mixed cryoglobulin complexes with decreasing temp provides analogous nucleation sites. The latter stages of precipitation appear to be kinetically similar for all proteins examined, although the size and shape of the aggregates are quite variable.

Portal and arterial washout after hypothermic preservation of the pig liver: prevention of hyperkalaemia after revascularization.

In an orthotopic liver transplantation (OLT), portal revascularization may produce acidosis and hyperkalaemia due to loss of intracellular acid metabolites and K+ during hypothermic preservation. To verify the effectiveness of portal and arterial washout in preventing hypokalaemia after liver preservation, an OLT was done in 18 large-white pigs. The donor livers were perfused in situ via the portal vein with Hartmann's solution containing 1.000 IU of heparin at 4 degrees C. Afterwards, a cold Collins C2 solution was perfused either in vitro (group A) or in situ (group B). The cold ischemia time in both groups was less than 3 1/2 h. Before doing the portal revascularization of the donor livers, a washout via the portal vein and hepatic artery with saline serum was performed. The concentration of K+, glucose, GOT and LDH in effluents obtained through infrahepatic inferior vena cava were significantly lower in group B than in group A. Simple washout of the livers prior to revascularization prevented hyperkalaemia in both groups.

Thermodynamics of monoclonal and mixed cryoimmunoglobin solubilization.

The direct calorimetric determination of heats of solution for four monoclonal and three mixed (IgM/IgG) cryoglobulins is described. Values obtained by differential scanning calorimetry (DSC) are compared to values of the apparent delta Hsol obtained by a polyethylene glycol (PEG) precipitation method. The four monoclonal cryoglobulins manifest heats of solution determined by DSC to be of the same order of magnitude as heats obtained by PEG precipitation, although DSC values were 25 to 125% lower than the corresponding van't Hoff enthalpies. Values of delta Hsol for mixed cryoglobulins were significantly greater than monoclonal cryoglobulins on a molar basis. These higher values are primarily attributed to the greater surface area of these complexes which results in more extensive contact between molecules in the solid phase. No evidence was found that conformational changes contributed to the calorimetric delta Hsol values employing a variety of spectroscopic methods.

The temperature-dependent stoichiometry of mixed cryoimmunoglobulins.

The interaction of three monoclonal rheumatoid factor IgM molecules with IgG antigens has been studied utilizing immunoglobulins isolated from three mixed cryoglobulins. Static light scattering measurements show that the stoichiometry of these immune complexes changes in a temperature-dependent manner from IgM(IgG)0-2 at temperatures greater than 37 degrees C to IgM(IgG)5 complexes at temperatures below 15 degrees C. These results were confirmed by the analysis of the composition of polyethyleneglycol-precipitated complexes. For one mixed cryoglobulin (Glo), temperature-dependent changes in stoichiometry were also verified by chemical cross-linking studies. Binding constants were determined by Scatchard analysis of light scattering data and by fluorescence polarization measurements. Values on the order of 10(5) M-1 were obtained for three monoclonal rheumatoid factor IgM molecules. Glo was further investigated by dynamic light scattering and partial specific volume measurements. Both dynamic light scattering and partial specific volume measurements provided evidence for surprising shape changes of the IgM X IgG complex as a function of temperature and IgG stoichiometry. Collectively, the data support the simple hypothesis that cryoprecipitation of mixed cryoglobulins occurs as a consequence of increases in the size (stoichiometry) of the complexes that are formed at low temperatures.