BTLA expression declines on B cells of the aged and is associated with low responsiveness to the trivalent influenza vaccine

Virus-neutralizing antibody and B cell responses to influenza A viruses were measured in 35 aged and 28 middle-aged individuals following vaccination with the 2012 and 2013 trivalent inactivated influenza vaccines. Antibody responses to the vaccine strains were lower in the aged. An analysis of B cell subsets by flow cytometry with stains for immunoregulators showed that B cells of multiple subsets from the aged as compared to younger human subjects showed differences in the expression of the co-inhibitor B and T lymphocyte attenuator (BTLA). Expression of BTLA inversely correlated with age and appears to be linked to shifting the nature of the response from IgM to IgG. High BTLA expression on mature B cells was linked to higher IgG responses to the H1N1 virus. Finally, high BTLA expression on isotype switched memory B cells was linked to better preservation of virus neutralizing antibody titers and improved recall responses to vaccination given the following year.     

Cytotoxicity of iron oxide nanoparticles made from the thermal decomposition of organometallics and aqueous phase transfer with Pluronic F127

Magnetic nanoparticles are promising molecular imaging agents due to their relatively high relaxivity and the potential to modify surface functionality to tailor biodistribution. In this work we describe the synthesis of magnetic nanoparticles using organic solvents with organometallic precursors. This method results in nanoparticles that are highly crystalline and have uniform size and shape. The ability to create a monodispersion of particles of the same size and shape results in unique magnetic properties that can be useful for biomedical applications with MR imaging. Before these nanoparticles can be used in biological applications, however, means are needed to make the nanoparticles soluble in aqueous solutions and the toxicity of these nanoparticles needs to be studied. We have developed two methods to surface modify and transfer these nanoparticles to the aqueous phase using the biocompatible co‐polymer, Pluronic F127. Cytotoxicity was found to be dependent on the coating procedure used. Nanoparticle effects on a cell‐culture model were quantified using concurrent assaying: a lactate dehydrogenase assay to determine cytotoxicity and a 3‐(4,5‐dimethylthiazol‐2‐yl)‐5‐(3‐carboxymethoxyphenyl)‐2‐(4‐sulfophenyl)‐2H‐tetrazolium, inner salt assay to determine viability for a 24 h incubation period. Concurrent assaying was done to insure that nanoparticles did not interfere with the colorimetric assay results. This report demonstrates that a monodispersion of nanoparticles of uniform size and shape can be manufactured. Initial cytotoxicity testing of new molecular imaging agents needs to be carefully constructed to avoid interference and erroneous results. Copyright © 2010 John Wiley & Sons, Ltd.     

Arteriovenous malformation of the external ear

Arteriovenous malformation (AVM) involving the external ears is relatively uncommon in adults. Arteriovenous malformations typically present during childhood and rarely manifest during adulthood in the head and neck region. Symptomatic arteriovenous malformations often pose difficult therapeutic challenges. We report a case of large arteriovenous malformation of the external ear in a 21-year-old female.     

Discharge pattern of renal sympathetic nerve activity in the conscious rat: spectral analysis of integrated activity

We investigated the periodic characteristics of bursting discharge in renal sympathetic nerve activity (RSNA) in conscious rats. Employing a discrete fast Fourier transform algorithm, a power spectrum analysis was used to quantify periodicities present in rectified and integrated RSNA whose signal-to-noise ratio in the recordings was greater than six. In conscious rats with intact baroreceptors, RSNA was characterized by four frequency components occurring at about 0.5, 1.5, 6, and 12 Hz, which corresponded to the low-frequency fluctuation of heart rate, respiration, and frequency of heart beat, and its harmonics, respectively. After intravenous infusion of sodium nitroprusside (SNP) to elicit reflex increases in RSNA and heart rate, the power for the component at 6 Hz followed the changes in heart beat frequency and was significantly increased, while those for the three other components were attenuated or experienced no change. In sino-aortic denervated (SAD) conscious rats, all four components were abolished, and the power spectrum was well fitted by a flat or Lorentzian curve, suggesting an almost random pattern. Only a respiratory-related component, which suggested common central modulation, appeared sporadically for short periods but was absent for the most part. Therefore most of this component together with the low-frequency component was also likely due to the baroreceptor-dependent peripheral modulation. The activity was sorted in 15 subgroups on the basis of spike amplitudes in the RSNA. Each subgroup showed frequency characteristics similar to the whole nerve activity. These results suggest that all periodicity in the RSNA of conscious rats with intact baroreceptors is caused by the baroreceptor input.     

Metastatic malignant teratoid medulloepithelioma - a case report and review of the literature

Medulloepitheliomas are rare congenital tumours arising from the epithelium lining the medullary tube. They are usually detected in the first decade of life. They may be teratoid or non-teratoid. Regional and distant metastases are rare. Extraocular extension of disease appears to be the most important prognostic feature. Surgical resection is the usual mode of treatment. The role of other adjuvant modalities is as yet unclear.     

Sustained complete remission of stage IV carcinoma of the pyriform fossa following chemotherapy

Tumours of the hypopharynx continue to have one of the most dismal prognoses of all tumours of the upper aerodigestive tract. These tumours are frequently advanced at the time of diagnosis. They have a particularly high propensity for lymphatic spread. Treatment, thus appears difficult from the outset. Although therapeutic protocols have improved, their often radical nature is synonymous with poor tolerance. With neoadjuvant chemotherapy and reconstructive surgery, cure has become a possibility for an increasing number of patients. However, sustained long-term remission following chemotherapy alone for advanced hypopharyngeal tumours has seldom been recorded.