Biodegradable implants for Pipkin fractures

The current study was designed to clarify whether biodegradable poly-L/DL lactide pins provide an operative alternative for fixation of Pipkin fractures. Nine patients with Pipkin fractures (one with Pipkin Type I, one with Pipkin Type II, and seven with Pipkin Type IV fractures) were treated surgically between 1996 and 2002. In all patients, the femoral head fractures were fixed with biodegradable, 2.7-mm and 2.0-mm polylactide pins. Eight patients were followed up for an average of 54.2 months. One patient died before the final followup. Eight fractures healed uneventfully. In one patient, a persisting femoral head defect led to posttraumatic arthritis requiring insertion of a femoral endoprosthesis at 1 year. The average range of motion of the affected hips of all patients at followup was 109 degrees -0 degrees -0 degrees in flexion and extension. External and internal rotation averaged 37 degrees -0 degrees -29 degrees . One patient had Brooker Grade I heterotopic ossification develop, and another had a Grade II heterotopic develop. Merle d'Aubigne and Postel ratings showed two excellent and five satisfactory results (average score, 13.1). Adverse effects from the polylactide implants were not observed. Pipkin fractures can be fixed successfully with biodegradable polylactide pins.     

Comparison of magnetic properties of MRI contrast media solutions at different magnetic field strengths

RATIONALE AND OBJECTIVES: To characterize and compare commercially available contrast media (CM) for magnetic resonance imaging (MRI) in terms of their relaxivity at magnetic field strengths ranging from 0.47 T to 4.7 T at physiological temperatures in water and in plasma. Relaxivities also were quantified in whole blood at 1.5 T. METHODS: Relaxivities of MRI-CM were determined by nuclear magnetic resonance (NMR) spectroscopy at 0.47 T and MRI phantom measurements at 1.5 T, 3 T, and 4.7 T, respectively. Both longitudinal (T1) and transverse relaxation times (T2) were measured by appropriate spin-echo sequences. Nuclear magnetic resonance dispersion (NMRD) profiles were also determined for all agents in water and in plasma. RESULTS: Significant dependencies of relaxivities on the field strength and solvents were quantified. Protein binding leads to both increased field strength and solvent dependencies and hence to significantly altered T1 relaxivity values at higher magnetic field strengths. CONCLUSIONS: Awareness of the field strength and solvent associated with relaxivity data is crucial for the comparison and evaluation of relaxivity values. Data observed at 0.47 T can thus be misleading and should be replaced by relaxivities measured at 1.5 T and at 3 T in plasma at physiological temperature.     

Prime-boost immunization using DNA vaccine and recombinant Orf virus protects pigs against Pseudorabies virus (Herpes suid 1)

The present study demonstrates the protective potential of a novel prime-boost vaccination strategy of pigs against lethal Pseudorabies virus (PRV; Herpes suid 1) infection. Animals were primed with Sindbis virus-derived plasmids that express viral glycoproteins gC and gD (gC- and gD-pSIN) and subsequently booster immunized with Orf virus (ORFV; Parapoxvirus) recombinants expressing gC and gD (D1701-VrVgC and -VrVgD). The prime-boost vaccination induced strong humoral and cellular-like PRV-specific immune responses. All prime-boost vaccinated pigs survived the lethal challenge infection without PRV-specific clinical symptoms and presented excellent body weight loss attenuation. Most notably, nasal shedding of challenge virus was reduced by more than about 3log(10), clearly reducing the risk of infection of non-immunized pigs.     

Gadofluorine-enhanced magnetic resonance imaging of carotid atherosclerosis in Yucatan miniswine

OBJECTIVE: The aim of this study was to determine whether gadofluorine, a paramagnetic magnetic resonance imaging (MRI) contrast agent, selectively enhances carotid atherosclerotic plaques in Yucatan miniswine. METHODS: Atherosclerotic plaques were induced in the left carotid arteries (LCA) of Yucatan miniswine (n=3) by balloon denudation and high cholesterol diet. T1-weighted MRI was performed before and 24 hours after gadofluorine injection (at a dose of 100 micromol/kg) to assess the enhancement of the balloon-injured LCA wall relative to healthy, uninjured right carotid artery (RCA) wall. Histopathology was performed to verify the presence and composition of the atherosclerotic plaques imaged with MRI. RESULTS: Gadofluorine was found to enhance LCA atherosclerotic lesions relative to RCA wall by 21% (P<0.025) 24 hours after contrast injection. Enhancement of healthy LCA wall relative to healthy RCA wall was not observed. CONCLUSION: Gadofluorine selectively enhances carotid atherosclerotic plaques in Yucatan miniswine. Gadofluorine appears to be a promising MR contrast agent for detection of atherosclerotic plaques in vivo.     

CT angiography with gadolinium-based contrast media

RATIONALE AND OBJECTIVES: To evaluate the potential use of gadolinium (Gd)-based contrast media, especially that of Gadovist, a 1-molar Gd medium, in computed tomography (CT) and compare our findings with standard iodinated contrast media. MATERIAL AND METHODS: Using a live rabbit and an acrylic CT body phantom for comparative CT imaging of Gd- and I-based media. The images were acquired at 80, 100, and 120 kVp, using fixed standard beam filtration. The phantom study used serial dilutions of the Magnevist and Ultravist 300 (2.4-molar I), whereas the animal study used different volumes of Gadovist, Magnevist (0.5 molar Gd), and Ultravist administered intravenously. RESULTS: At 80 kVp for the same injection volumes of Gadovist and Ultravist, the image contrast enhancement of the aorta with Gadovist was 40% lower than that of Ultravist. In the phantom studies, however, for the same kVp settings the CT image contrast was up to fourfold higher for Gd compared with iodine when comparing the same molar concentrations of the two elements in the solutions. CONCLUSION: These results indicate a potential of Gd-based media for clinical CT angiography and provide incentive for further investigation of this subject.     

Development of an ELISA for detection of antibodies to glycoprotein I of Aujeszky's disease virus: a method for the serological differentiation between infected and vaccinated pigs

A blocking ELISA was developed to distinguish between Aujeszky's disease virus (ADV)-infected and vaccinated pigs, on the basis of presence or absence of serum antibodies to glycoprotein I (gI) of ADV. The gI-ELISA detects antibodies that block the reaction of monoclonal antibodies to one or two epitopes on gI of ADV. The ADV-gI antibody response appeared between one and two weeks post-infection and persisted at a high level for at least seven months. Five of the nine ADV-vaccine strains examined were found to be "gI-negative". Pigs vaccinated with a gI-negative vaccine did not develop an ADV-gI antibody response until they were challenge-exposed to a virulent strain of ADV. The gI-ELISA is highly specific, sensitive and suitable for large-scale sero-epidemiological studies to identify infected pigs in populations vaccinated with gI-negative vaccines. The gI-ELISA provides, therefore, a basis for ADV-eradication programmes, which introduces a novel concept in the control of animal virus diseases.     

Imaging of myocardial infarction: comparison of magnevist and gadophrin-3 in rabbits

OBJECTIVES: This study was designed to determine the enhancement profile of a necrosis-specific contrast agent (gadophrin III) in comparison to a standard extracellular agent on T1-weighted magnetic resonance (MR) images in acute and chronic myocardial infarctions (MIs). BACKGROUND: Contrast-enhanced MR imaging demonstrated the ability to accurately quantify infarct size; however, some controversies persist about which contrast medium is best suited. METHODS: Fifteen rabbits underwent thoracotomy and permanent occlusion of a branch of the left coronary artery. Two animals died before imaging, eight were examined 48 h after occlusion and five animals were imaged six weeks following induction of infarction. All animals received 50 micromol/kg of gadophrin-3 24 h before the MR examination. Continuous short-axis views were collected using an inversion recovery turbo fast low angle shot sequence. Imaging was repeated 5 to 10 min following additional injection of 100 micromol/kg of Magnevist. The area of hyperenhancement demarcated following gadophrin-3 injection was compared with the region of hyperenhancement seen on gadophrin-3 plus Magnevist enhanced image using triphenyltetrazolium chloride (TTC) staining as the standard of reference. RESULTS: In acute MI the mean difference in size of hyperenhancement seen on the two different in vivo MR scans was -1.8 +/- 6.0 mm(2) (p > 0.05). Both measurements showed excellent agreement with TTC staining. Chronic MIs showed no enhancement with gadophrin-3, whereas application of Magnevist resulted in hyperenhancement. CONCLUSIONS; Standard extracellular contrast agents do not overestimate the size of acute MI. The combination of gadophrin-3 and Magnevist can distinguish acute and chronic myocardial injury because chronic MIs do not enhance with gadophrin-3.     

BK virus infections in children with various primary immunodeficiencies and in related healthy household contact persons

Summary Sera from 26 patients with different inherited immunodeficiences were tested for specific antibodies to BK virus (BKV) in the hemagglutination inhibition (HI) and the IgM — immunofluorescence (IF) test. Eighty-one percent exhibited HI-antibodies to BKV, whereas virus-specific IgM antibodies were not found in a single case. Serial serum samples from seven patients did not show significant titer changes during the observation period of up to two years. A comparison was made between the antibody levels of the sera tested and the occurrence of BKV in the corresponding urine samples. Furthermore, in eight patients the seroreactivity of related close household contact persons was investigated. Seven of the 17 healthy relatives investigated had BKV-specific IgM antibodies and most of them revealed high serum antibody levels in the HI-test.

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BK-Virusinfektionen bei Kindern mit primären Immundefizienzen und verwandten gesunden Kontaktpersonen

Zusammenfassung Die Seren von 26 Patienten mit verschiedenen primären Immundefizienzen wurden mit dem Hämagglutinationshemmtest (HHT) und einem IgM-Immunfluoreszenztest (IF) auf den Gehalt an spezifischen Antikörpern gegen BK-Virus (BKV) untersucht. 81% der Patienten wiesen HHT-Antikörper gegen BKV auf, aber in keinem Fall wurden virusspezifische IgM-Antikörper gefunden. Bei Verlaufskontrollen über bis zu zwei Jahren fanden sich bei sieben Patienten keine signifikanten Titeränderungen. Es wurden die Antikörpertiter mit dem Vorkommen von BKV in Urinproben verglichen, sowie die Seroreaktivität von Haushalt-Kontaktpersonen der Patienten in acht Fällen untersucht. Sieben der 17 untersuchten, klinisch gesunden Verwandten wiesen BKV-spezifische IgM-Antikörper auf, und die meisten von ihnen waren mit hohen HHT-Antikörpern korreliert.