The presence of the virulence island containing the usp gene in uropathogenic Escherichia coli is associated with urinary tract infection in an experimental mouse model

Purpose: A putative virulence island commonly noted in the genome of uropathogenic Escherichia coli strains has recently been reported. We have observed that the island includes a gene consisting of a protein designated uropathogenic specific protein (usp) and 3 small open reading frames (orfU1-3). In our current study we assessed the importance of the genes located in the putative virulence island in the pathogenesis of urinary tract infection using a mouse pyelonephritis model. Materials and Methods: A total of 427 E. coli strains isolated from the urine of 194, 76 and 107 subjects suffering from cystitis, pyelonephritis and prostatitis, respectively, and 50 isolates from the feces of healthy individuals were examined for genotypes and serotypes. In addition, several recombinant E. coli strains possessing usp and/or orfU1 to 3 were constructed for evaluating the significance of these genes using an experimental pyelonephritis mouse model. Results: The usp was significantly more often associated with uropathogenic E. coli strains (79.4% from cystitis, 93.4% from pyelonephritis and 88.8% from prostatitis) than with fecal E. coli strains from healthy individuals (24%). Furthermore, usp was frequently associated with all common serotypes of uropathogenic E. coli (71.7% to 100%). In challenge experiments using the mouse urinary tract infection model the vector possessing usp significantly enhanced the infectibility of the E. coli host cell, whereas the 3 small proteins at the downstream of usp failed to show the effect. Conclusion: Our results indicate that usp may contribute to the causation of urinary tract infection and may be considered a major virulence determinant of uropathogenic E. coli

Massive true thymic hyperplasia with osseous metaplasia

True thymic hyperplasia is defined as an increase in both the size and weight of the gland, while maintaining a normal microscopic architecture. Massive true thymic hyperplasia is a rare type of hyperplasia that compresses adjacent structures and causes various symptoms.Limited reports address the imaging findings of massive true thymic hyperplasia. Herein, we report a case of massive true thymic hyperplasia in a 3-year-old girl with no remarkable medical history. Contrast-enhanced CT revealed an anterior mediastinal mass with a bilobed configuration containing punctate and linear calcifications in curvilinear septa, which corresponded to lamellar bone deposits in the interlobular septa. To our knowledge, this is the first report of massive true thymic hyperplasia with osseous metaplasia. We also discuss the imaging features and etiology of massive true thymic hyperplasia with osseous metaplasia

The long-term freshening and nutrient increases in summer surface water in the northern East China Sea in relation to Changjiang discharge variation

Using historical in situ data sets, we investigated long-term variations in summer surface salinity and dissolved inorganic nitrogen concentration (DIN) in the northern East China Sea (ECS). From 1950 to 2002, there were interannual and decadal variations in sea surface salinity, as well as a long-term decrease. Along with the Changjiang discharge, wind fields and surface circulations appeared to play roles in determining the interannual salinity variation. Although we attributed the long-term decrease in surface salinity to a long-term increase in the Changjiang discharge, the high salinity between 1978 and 1988 appeared to be associated with an increase in the Kuroshio Current transport. The increase in DIN from 1971 to 2001 appeared to be caused by a combination of changes in Changjiang discharge and an increase in nitrogen fertilizer use in China. The long-term increase in DIN modified the nutrient composition, implying that biological production in the northern ECS changed from a DIN-limiting to a phosphorous-limiting. We should pay attention to changes in the northern ECS ecosystem in future decades because the volume of the Changjiang discharge, as well as its physical and chemical properties, may change dramatically because of the continuous anthropogenic perturbations and climate change