Mutation Patterns in the Chemokine CXC Receptor 4 Gene Subfamily

Six representative CXCR4 mRNAs of fish, amphibia, birds, and mammals were selected to study the pattern of conservation/mutation of the individual nt of the coding sequences. According to an arbitrary conservation index ranging from 1 to 6, the indexes of conservation were: 5.04 for the first nt of coding triplets; 5.34 for the second nt of triplets, and 3.75 for the third nt of triplets. The average conservation index of the individual triplets was 4.71. The conservation index of the seven hydrophobic transmembrane domains was 5.60, while the cumulative conservation index of the intracytoplasmic and extracellular domains was 4.63. Separate autocorrelation and power spectral analyses of the series of conservation indexes for the first nt, the second nt and the triplets demonstrated a modest “basic” positive correlation for about the first 20 lags and accordingly some power concentration at the lower frequencies (long periods). Within the triplets, the correlation was studied between the conservation indexes of nt 1 and 2, 1 and 3, and 2 and 3. Correlations of 1 with 3 and 2 with 3 were positive, but in the range of the basic local correlation, whereas the correlation between the first and second nt was significantly higher. This correlation, together with the higher conservation of the second nt as compared to the first (two patterns also found in the formyl peptide receptors), are likely to have been established by selection processes directed towards a functional conservation or a “functional repair.”     

Incidental detection and monitoring of spontaneous recovery of sarcoidosis via fluorine-18-fluoroethyl-choline positron emission tomography/computed tomography

We report a case of sarcoidosis detected incidentally by using fluorine-18-fluoroethylcholine- positron emission tomography/computed tomography (1?F-FECH-PET/CT) in a 72 years old patient with prostate cancer, who had been referred for restaging after relapse indicated prostate specific antigen (PSA). The 1?F-FECH-PET/CT examination showed a focal increased uptake in the prostate bed suggestive for local recurrence, in addition to multifocal uptake in the mediastinum matching with enlarged hilar and paratracheal lymph nodes. Histopathology revealed sarcoidosis. No treatment was recommended. Two years later the patient was referred again to us because of another recurrent PSA elevation. The second 1?F-FECH-PET/CT showed again the previously described local recurrence, but did not show the previously described mediastinal findings nor the enlarged hilar and paratracheal lymph nodes, thus, illustrating spontaneous healing of sarcoidosis. In conclusion, this case suggests that 1?F-FECH PET/CT study can show positive findings in sarcoidosis that were no longer detectable after two years, suggestive of spontaneous recovery.     

Glial hypothalamic inhibition of GLUT2 expression alters satiety,impacting eating behavior

Glucose is a key modulator of feeding behavior. By acting in peripheral tissues and in the central nervous system, it directly controls the secretion of hormones and neuropeptides and modulates the activity of the autonomic nervous system. GLUT2 is required for several glucoregulatory responses in the brain, including feeding behavior, and is localized in the hypothalamus and brainstem, which are the main centers that control this behavior. In the hypothalamus, GLUT2 has been detected in glial cells, known as tanycytes, which line the basal walls of the third ventricle (3V). This study aimed to clarify the role of GLUT2 expression in tanycytes in feeding behavior using 3V injections of an adenovirus encoding a shRNA against GLUT2 and the reporter EGFP (Ad‐shGLUT2). Efficient in vivo GLUT2 knockdown in rat hypothalamic tissue was demonstrated by qPCR and Western blot analyses. Specificity of cell transduction in the hypothalamus and brainstem was evaluated by EGFP‐fluorescence and immunohistochemistry, which showed EGFP expression specifically in ependymal cells, including tanycytes. The altered mRNA levels of both orexigenic and anorexigenic neuropeptides suggested a loss of response to increased glucose in the 3V. Feeding behavior analysis in the fasting‐feeding transition revealed that GLUT2‐knockdown rats had increased food intake and body weight, suggesting an inhibitory effect on satiety. Taken together, suppression of GLUT2 expression in tanycytes disrupted the hypothalamic glucosensing mechanism, which altered the feeding behavior.     

Tetracycline and streptomycin resistance genes, transposons, and plasmids in Salmonella enterica isolates from animals in Italy

Fifty-eight multidrug-resistant Salmonella enterica strains of 20 serotypes, isolated from animal sources in Italy, were analyzed for tet(A) and strA-strB, conferring tetracycline and streptomycin resistance, respectively. The strA and strB genes were highly prevalent in Salmonella strains of our collection, being detected in 84% of the streptomycin-resistant strains. In many strains, the strA and strB genes were linked to a particular Tn5393-derivative transposon characterized by the presence of the insertion sequence IS1133, previously identified only in the plant pathogen Erwinia amylovora. Sixty-eight percent of the tetracycline-resistant strains were tet(A) positive, indicating that this gene is widely diffused in Salmonella strains circulating in animals in Italy. Most of the tet(A) genes were localized within a deleted Tn1721 transposon variant. Two prevalent repN and repI1 resistance plasmids were identified in Salmonella isolates of our collection.     

A human immunodeficiency virus type 1 pol gene-derived sequence (cPPT/CTS) increases the efficiency of transduction of human nondividing monocytes and T lymphocytes by lentiviral vectors

We have investigated the capacity of two human immunodeficiency virus type 1-derived lentivectors, differing in the presence of a 118-bp pol fragment containing the cPPT/CTS element, to transduce human normal primary cells of different hematopoietic lineages. Infection of resting monocytes with a high multiplicity of infection (MOI > 10) revealed that the lentivirus carrying the pol fragment (cPPT) is effective, transducing 75% of cells compared with 36% for the no-cPPT vector. Even at low MOIs (< or =1) the cPPT vector still shows a better transduction efficiency than the no-cPPT vector. Moreover, transduction does not require dendritic cell differentiation. In contrast, infection of nonactivated T lymphocytes showed that both vectors, tested at high MOIs, can transduce a small, although measurable, percentage of cells (up to 10%), which may correspond to G(1a) "activated" cells as detected by simultaneous staining of DNA and RNA, in our cultures in the presence of medium alone. Furthermore, we show that the sole addition of interleukin 2 or interleukin 15 represents a full proliferative signal under our conditions and permits high transduction efficiency (up to 30% with the cPPT vector and 15% with the no-cPPT vector). Still higher transduction of T lymphocytes can be achieved after stimulation with phytohemagglutinin and interleukin 2 (up to 78% with the cPPT vector vs. 42% with the no-cPPT vector). Finally, both viruses do not transduce either resting or proliferating tonsillar B lymphocytes.