One of the main goals in cancer immunotherapy is the efficient activation of the host immune system against tumour cells. Dendritic cells (DCs) can induce specific anti-tumour immune responses in both experimental animal models and humans. However, most preclinical studies using small animal models show only limited correlation with studies carried out in clinical settings, whereas laboratory dogs naturally develop tumours that are biologically and histopathologically similar to their human counterparts. Here, we describe the generation and characterization of recombinant antibodies against canine DCs, isolated using the Tomlinson phage display system. We successfully isolated highly specific single-chain variable fragment (scFv) antibodies in a sequential three-step panning strategy involving depletion on canine peripheral blood mononuclear cells followed by positive selection on native canine DCs. This provides the basis for an antibody-based method for the immunological detection and manipulation of DCs and for monitoring antigen-specific immune responses.

We present the synthesis and the tunneling spectroscopy study of superconducting FeSe(0.5)Te(0.5)(T(c)= 14 K), SmFeAsO(0.85)(T(c)= 54 K) and SmFeAsO(0.9)F(0.1)(T(c)= 45 K). The samples were characterized by Rietveld refinement of x-ray diffraction patterns and transport as well as temperature-dependent magnetic measurements. Tunneling experiments on FeSe(0.5)Te(0.5) revealed a single superconducting gap ∼ 1 meV in BCS-like tunneling conductance spectra. In SmFeAsO(0.85) and SmFeAsO(0.9)F(0.1), however, more complex spectra were observed, characterized by two gap-like structures at ∼ 4 and ∼ 10 meV. These spectra are qualitatively understood assuming a two-band superconductor with a 's ±' order parameter. We show that, depending on the sign relation between the pairing amplitudes in the two bands, the interband quasiparticle scattering has a crucial effect on the shape of the tunneling spectra. On the other hand, single-gap spectra found in FeSe(0.5)Te(0.5) are more compatible with a disorder-induced 's '-wave gap, due to the Se-Te substitution.

BACKGROUND. In patients with chronic hepatitis B, treatment with interferon alfa and the consequent loss of hepatitis B e antigen (HBeAg) from the blood leads to a reduction in inflammatory activity, but the clinical benefits of this treatment have not been established. We evaluated whether HBeAg seroconversion induced by interferon alfa improves clinical outcome. METHODS. We studied prospectively a cohort of 103 patients treated with interferon alfa for chronic hepatitis B; the mean (+/- SD) follow-up was 50.0 +/- 19.8 months. Fifty-three untreated patients served as controls. RESULTS. After treatment with interferon alfa, 53 of 103 patients no longer had detectable HBeAg or hepatitis B virus DNA, although only 10 patients became seronegative for hepatitis B surface antigen (HBsAg)(Kaplan-Meier estimates of cumulative clearance rates at five years, 56.0 percent for HBeAg and 11.6 percent for HBsAg). Of the 53 untreated patients, only 7 spontaneously eliminated HBeAg (28.1 percent at five years), and all remained positive for HBsAg (p < 0.001 for the Comparison with the treated patients, by the proportional-hazards model). During follow-up, 6 of the 103 treated patients died of liver failure, and 2 needed liver transplantation, all 8 were persistently positive for HBeAg. In another eight treated patients, complications of cirrhosis developed; all but one of these patients remained positive for HBeAg. Overall survival and survival without clinical complications were significantly longer in patients who were seronegative for HBeAg after therapy with interferon alfa than in those who remained seropositive (P = 0.004 and P = 0.018, respectively). In a regression analysis, clearance of HBeAg was the strongest predictor of survival. Of the 53 untreated patients, 13 had severe complications (including 4 deaths and 1 need for liver transplantation); all 13 continued to be HBeAg-positive. CONCLUSIONS. In patients with chronic hepatitis B infection, the clearance of HBeAg after treatment with interferon alfa is associated with improved clinical outcomes.

The prognosis of chronic hepatitis C virus (HCV) infection is still ill-defined. The present study prospectively evaluated mortality and complications in a large cohort of patients with chronic hepatitis C. The study included 838 anti-HCV and HCV-RNA-positive patients who were followed for 50.2 +/- 26.9 months (mean +/- SD; range, 6-122 months) in a prospective protocol. During follow-up, 62 patients died (31 from liver disease and 31 from other causes), and 12 patients needed liver transplantation. When compared with a matched general population, hepatitis C increased mortality mainly when cirrhosis was present and in patients who were less than 50 years old at study entry. During follow-up, a further 30 patients developed nonlethal complications of cirrhosis. By multivariate regression, survival was decreased by cirrhosis, long disease duration, history of intravenous drug abuse, and excessive alcohol consumption, whereas interferon therapy improved survival. Alanine transaminase (ALT), bilirubin, sex, and genotype had no effect on survival. The risk of hepatocellular carcinoma (HCC)(n = 17) was increased by cirrhosis and to a lesser degree by long disease duration and high bilirubin, whereas interferon therapy, genotype, and other factors had no effect. Chronic hepatitis C is a disease with considerable mortality and morbidity when cirrhosis is present at diagnosis. Patients who acquire the infection early in life have a markedly increased mortality even when cirrhosis is absent at diagnosis. The age at diagnosis therefore should play a major role in therapeutic considerations. The present data also suggest that interferon therapy has a long-term clinical benefit, although it did not reduce the risk of liver cancer.

Multiplicity of data, hypotheses, and analyses is a common problem in biomedical and epidemiological research. Multiple testing theory provides a framework for defining and controlling appropriate error rates in order to protect against wrong conclusions. However, the corresponding multiple test procedures are underutilized in biomedical and epidemiological research. In this article, the existing multiple test procedures are summarized for the most important multiplicity situations. It is emphasized that adjustments for multiple testing are required in confirmatory studies whenever results from multiple tests have to be combined in one final conclusion and decision. In case of multiple significance tests a note on the error rate that will be controlled for is desirable.

Staphylococcus aureus arthritis is usually caused by bacteremia and is highly destructive. Controlled studies on septic arthritis in humans are difficult to perform, because the time of onset of the infection is unknown. Animal models of bacterial arthritis make it possible to control important variables in experimental studies. We present a mouse model of S. aureus arthritis in which the intravenous administration of 10(7) cells of S. aureus LS-1 induced arthritis or osteitis or both within 3 weeks in 80 to 90% of the mice. Signs of arthritis emerged within the first few days after the injection. An interesting finding was that the S. aureus strain used in this study binds bone sialoprotein, a glycoprotein known to be specifically localized to bone tissue. This new model of S. aureus arthritis enables the study of the kinetics of joint destruction and the host-bacterium relationship as well as therapeutical approaches to septic arthritis and osteomyelitis.

The importance of locally and systemically formed antibodies of various classes for protection against experimental cholera has been studied in mice immunized with cholera toxin. Groups of mice were given various numbers of peroral or intravenous immunizations, or a combination of both. Serum antibodies and antibodies synthesized by spleen and small intestine in vitro during tissue culture were measured by the enzyme-linked immunosorbent assay, and protective immunity against intestinal toxin challenge was determined by means of a small-bowel loop assay. Regression analyses showed a close correlation between the magnitude of intestinal synthesis of specific immunoglobulin A (IgA) antibodies and protection (r = 0.98), whereas neither the local formation of IgG or IgM nor the production of antitoxin antibodies of any immunoglobulin class by spleen showed any significant correlation with protection. The serum titers of IgG and IgM antibodies did not show any such relation, whereas the level of specific IgA in serum, probably mainly derived from the intestine, correlated significantly (r = 0.90).

Staphylococcus aureus is the most common bacterial species found in association with nongonococcal bacterial arthritis in humans. We present here the first description of spontaneous bacterial arthritis and osteitis in mice. Clinically, the most obvious findings were swelling and/or ankylosis of hindpaws and nodose changes of the tail. The prevalence of arthritis and osteitis ranged from 0% to greater than 50% of the mice studied, depending on the mouse strain. The most prominent histopathologic feature of the arthritis was hypertrophy of the synovial tissue and destruction of cartilage and underlying bone. Most of the S aureus-infected mice displayed an identical phage type, which was also the only S aureus phage type found in skin isolates from clinically healthy mice. However, a few S aureus isolates were not typeable, indicating that an additional strain(s) might cause bacterial arthritis in mice.

BACKGROUND: Many physicians still believe that iron overload (hemochromatosis) is an uncommon disorder. OBJECTIVE: To estimate the frequency of iron overload and iron deficiency in a group of employees and a group of outpatients. DESIGN: Prospective screening study. SETTING: Western Germany. PARTICIPANTS: 3012 asymptomatic employees and 3027 outpatients of nine practitioners. MEASUREMENTS: Serum ferritin levels and transferrin saturation were measured. Participants with repeatedly abnormal results had thorough clinical evaluations to identify the cause of iron deficiency or overload. RESULTS: Gross iron overload (elevated transferrin saturation and ferritin levels) was proven by liver biopsy and phlebotomy treatment in 28 participants (0.4% of female outpatients, 0.7% of male outpatients, 0.2% of female employees, and 0.4% of male employees) and in six siblings of these participants. Of the 34 participants with iron overload, 30 were precirrhotic. Because 60% of an unselected group of employees with elevated transferrin saturation but normal ferritin levels were assumed to have early hemochromatosis, the prevalence of hemochromatosis was estimated to be 1.8% among patients (1.9% in women and 1.6% in men) and 1.0% among employees (1.1% in women and 1.0% in men). Iron deficiency was found in 6.8% of female patients, 2.4% of male patients, 6.0% of female employees, and 0.5% of male employees. CONCLUSIONS: Iron deficiency was more common in women, and iron overload was more common in men. Among male employees, iron overload was almost as common as iron deficiency.

An adult mouse model has been elaborated for studies of experimental cholera (Vibrio cholerae enterotoxin-induced intestinal secretion) and protective antitoxic immunity in either ligated small bowel loops or intact small intestine. Mice of different inbred strains varied markedly in intestinal susceptibility to toxin, C57B1 being the most sensitive strain tested. Fluid accumulation started within 1 h after the inoculation of toxin and was maximal after 5 h, whereafter recovery gradually ensued. The dose-response curve was sigmoid, the ED50 of crude toxin being equivalent to about 0.1 microgram purified toxin/cm in the loops and 0.3 microgram/cm in the nonligated intestine. Two peroral (p.o.) immunizations induced significant protective immunity which increased markedly after two further immunizations by the same route. Additional p.o. immunizations did not appreciably enhance the protective immunity any further. Intravenous (i.v.) vaccination had to be repeated more than 5 times before intestinal immunity could be observed. No correlation between serum antitoxin titers and protective immunity was found. Electron microscopic examination revealed that whereas peroxidase-coupled cholera toxin bound tightly to intestinal microvilli from unimmunized or 5-times i.v. immunized mice it did not bind to the microvilli of p.o. immunized animals. The data thus suggest that the protective immunity is mediated exclusively by locally produced antibodies which prevent the binding to toxin to the gut epithelium.

In 1982 a new measure was introduced in research into osteoporosis and is now used everywhere in the literature. The so called "fracture rate" relates the number of fractures (single in some patients, multiple in others) to the cumulative time of observation of all patients. This concept, however, has no sound basis. Counting events instead of patients usually violates basic statistical assumptions and invalidates the use of common statistical tests and estimators. Its clinical interpretation is rather dubious. The use of such a measure impedes the search for valid and clinically meaningful outcome criteria and should be abandoned.