X-ray CT and pneumonia inhibition properties of gold-silver nanoparticles for targeting MRSA induced pneumonia.

Non-invasive assay for the early stage diagnosis of methicillin resistant Staphylococcus aureus (MRSA) related pneumonia is of great clinical importance and still a great challenge. In this paper, we reported a novel kind of Au@Ag core-shell theranostic nanoparticles (NPs) conjugated with MRSA specific antibody on their surface. Compared with the raw Au@Ag NPs, these antibody modified NPs (AAMA NPs) showed 10.66 fold enhancement targeting to the MRSA in vitro. In vivo target efficacy was measured with rats bearing pneumonia induced by different pathogens. Computed tomography (CT) results revealed that these AAMA NPs had higher CT contrast enhancement (498 HU), than those of raw Au@Ag and Omnipaque (oth <100 HU). In addition, lesions labeled by AAMA NPs could be distinguished from lung parenchyma by taking advantage of spectra CT. Bio-distribution analysis confirmed that these AAMA NPs accumulated in the MRSA rich site. Both BAL and Elisa assays indicated that these AAMA NPs greatly alleviated the inflammation reaction by reducing bacterial proliferation and cytokine production. Pathological study showed that these NPs exerted negligible long term cytotoxicity in vivo.

Characterization of the capsid protein VP2 gene of a virulent strain NE/09 of porcine parvovirus isolated in China.

A virulent strain NE/09 of porcine parvovirus (PPV) was isolated from mummified swine fetus samples in China and its capsid protein VP2 gene was analyzed. The data showed that the VP2 gene encompassed an open reading frame of 1713 nucleotides with a composition of 684 adenine (39.9%), 387 cytosine (22.6%), 268 guanine (15.7%), and 374 thymine (21.8%). The VP2 gene encoded a 570aa-long protein which could be recognized by anti-PPV-VP2 monoclonal antibody 3C9. Sequence analysis revealed that the VP2 gene of PPV-NE/09 had close sequence similarity with the VP2 gene of other PPV strains. However, a 27 nucleotide region that encodes a glycine-rich domain at the N-terminal region of VP2 was deleted in the PPV-NE/09 strain. The PPV-NE/09 virions were purified by 1.39 g/ml CsCl density centrifugation and subjected to SDS-PAGE analysis. The results showed that only two major polypeptides VP1 and VP2 with molecular weights of 83 and 64kDa, respectively were observed, whereas VP3 with a molecular weight of 60 kDa was not present, in contrast to the PPV-NADL-2 strain. According to the phylogenetic relationship of the VP2 gene of PPV-NE/09, the isolate was a new mutant strain of PPV prevailing in China.

RANTES deficiency attenuates autoantibody-induced glomerulonephritis.

Experimental autoimmune nephritis in mice and spontaneous lupus nephritis are both associated with elevated expression of several chemokines in the kidneys. Nevertheless, the role that different chemokines play in mediating renal inflammation is far from complete. This study focuses on elucidating the functional role of RANTES, a chemokine that has been noted to be hyper-expressed within the kidneys, both in experimental renal disease as well as in spontaneous lupus nephritis. To elucidate if RANTES was essential for immune-mediated glomerulonephritis, DBA/1 mice that are highly sensitive to nephrotoxic serum nephritis were rendered RANTES-deficient and then tested for disease susceptibility. Nephritis-sensitive DBA/1 mice expressed more RANTES within the diseased kidneys. Compared to wild-type DBA/1 mice, RANTES-deficient DBA/1 mice developed significantly less proteinuria, azotemia, and renal inflammation, with reduced crescent formation and tubulo-interstitial nephritis. These findings indicate that RANTES ablation attenuates immune-mediated nephritis and suggest that this chemokine could be a potential therapeutic target in these diseases.

Distinctive features of foreskin condylomata acuminata associated with diabetes mellitus.

The aim of this study was to test the hypothesis that particular clinical features of foreskin condylomata acuminata in Chinese male patients are associated with diabetes. A prospective study enrolled 126 men presenting with foreskin condylomata acuminata from 2001 to 2006. Mean age was 46 years (age range 25-74 years) and mean duration of disease was 4.8 months (range 1-18 months). Patients were divided into two groups according to clinical features. In group 1, 42 men had distinctive signs such as redundant prepuce, crown warts circling the entire preputial ring, maceration, fissures, phimosis and balanitis, and 37 of 42 (88%) patients were found to have concurrent type 2 diabetes, furthermore 32 of these 37 patients had an insidious onset and were previously undiagnosed. In group 2, 84 male patients did not have those distinctive clinical features and type 2 diabetes was found in only 10 cases (11.9%, p<0.0001, Fisher's exact test). These clinical features strongly suggest the presence of diabetes. Therapy should address diabetes and condylomata concurrently.

Elevated urinary VCAM-1, P-selectin, soluble TNF receptor-1, and CXC chemokine ligand 16 in multiple murine lupus strains and human lupus nephritis.

In an effort to identify potential biomarkers in lupus nephritis, urine from mice with spontaneous lupus nephritis was screened for the presence of VCAM-1, P-selectin, TNFR-1, and CXCL16, four molecules that had previously been shown to be elevated in experimental immune nephritis, particularly at the peak of disease. Interestingly, all four molecules were elevated approximately 2- to 4-fold in the urine of several strains of mice with spontaneous lupus nephritis, including the MRL/lpr, NZM2410, and B6.Sle1.lpr strains, correlating well with proteinuria. VCAM-1, P-selectin, TNFR-1, and CXCL16 were enriched in the urine compared with the serum particularly in active disease, and were shown to be expressed within the diseased kidneys. Finally, all four molecules were also elevated in the urine of patients with lupus nephritis, correlating well with urine protein levels and systemic lupus erythematosus disease activity index scores. In particular, urinary VCAM-1 and CXCL16 showed superior specificity and sensitivity in distinguishing subjects with active renal disease from the other systemic lupus erythematosus patients. These studies uncover VCAM-1, P-selectin, TNFR-1, and CXCL16 as a quartet of molecules that may have potential diagnostic significance in lupus nephritis. Longitudinal studies are warranted to establish the clinical use of these potential biomarkers.

Identification of a novel negative role of flagellin in regulating IL-10 production.

Toll-like receptors (TLR) expressed by cells of the immune system play a central role in the generation of immune responses against pathogens. Following TLR ligation, both pro-inflammatory and anti-inflammatory mediators are produced in order to elicit an immune response that controls the microbial infection while limiting tissue damage. Among these mediators, the pro-inflammatory cytokine IL-12 and the anti-inflammatory cytokine IL-10 are known to play major roles. Here, we show that in vitro or in vivo stimulation with flagellin, the TLR5 ligand, does not result in IL-10 production. Furthermore, flagellin inhibits IL-10 production by other specific TLR ligands at the protein and mRNA levels while increasing IL-12p70 production. Several studies have linked the activation of extracellular signal-regulated kinases with IL-10 induction by TLR. We have observed that LPS-induced extracellular signal-regulated kinase activation was significantly decreased in flagellin-treated macrophages, suggesting that this pathway might play a role in the inhibition of IL-10 production observed in flagellin-treated macrophages. Flagellin-mediated IL-10 inhibition was not observed in cells that do not express TLR5, supporting that this effect is indeed TLR5-dependent. This study provides a new insight into the role of flagellin recognition by TLR5 in shaping the immune response elicited by flagellated microorganisms.

Expression and characterization of Gag protein of HIV-1(CN) in Pichia pastoris.

To express the core protein of HIV-1 of Chinese prevalent strain (HIV-1(CN)) in Pichia pastoris, the full-length gag gene was inserted into the secretory expression vector pHILS1. Linearized recombinant plasmid pHILGAG by SalI was electrotransformed into the yeast strain GS115, and the yeast transformants were identified by PCR. To induce the interest protein to be expressed, the PCR positive transformants were inoculated in the medium of BMGY and BMMY, mRNA of the strain was detected by RT-PCR, and the expressed protein was analyzed by SDS-PAGE, Western blotting and thin layer scanning. mRNA (1.3kb) was amplified by RT-PCR. SDS-PAGE and Western blotting analysis showed that the molecular mass of the expressed protein was 55kDa, which was similar to the expected value, and the expressed protein could react with McAb to HIV-1 p24. Thin layer scanning analysis demonstrated that the whole amount of the expressed protein was approximately 13% of the soluble protein in the supernatant. The recombinant yeast had good genetic stability. The optimal expression conditions of the engineering yeast were as follows: BMMY medium, 80-90% of dissolved oxygen, 1% methanol, and 3-day-cultivation course. Gag proteins were expressed under the optimal expression condition and purified via gel filtration chromatography. The purity of the interest protein was up to 85%. After the purified proteins were inoculated into BALB/c mice, the anti-HIV-1 antibodies in the immunized mice could be detected by Western blotting.

Association of renal injury with nitric oxide deficiency in aged SHR: prevention by hypertension control with AT1 blockade.

BACKGROUND: Aged spontaneously hypertensive rats (SHR) develop end-stage renal disease resembling that of uncontrolled essential hypertension in humans. Nitric oxide (NO) and angiotensin II (Ang II) play an important role in the regulation of blood pressure and the growth of vascular smooth muscle and renal mesangial cells. The relationship between renal NO system, Ang II activity and renal injury in aged SHR is not fully understood. METHODS: The 8-week-old SHR were randomized into losartan-treated (30 mg/kg/day for 55 weeks) and vehicle treated groups. The age-matched Wistar-Kyoto rats (WKY) served as controls. Renal histology and tissue expressions of endothelial and inducible NO synthases (eNOS and iNOS) and nitrotyrosine were examined at 63-weeks of age. RESULTS: Compared to the WKY group, untreated SHR showed severe hypertension, proteinuria, renal insufficiency, a twofold decrease in renal tissue eNOS and iNOS expressions and massive nitrotyrosine accumulation. This was associated with severe glomerulosclerosis, tubular atrophy and interstitial fibrosis. Losartan therapy normalized blood pressure, prevented proteinuria and renal insufficiency, abrogated the fall in renal eNOS and iNOS protein contents, mitigated renal nitrotyrosine accumulation, and prevented the histological abnormalities found in the untreated SHR. CONCLUSIONS: Aged SHR exhibit severe renal lesions with acquired NO deficiency that are prevented by hypertension control with AT1 blockade. These findings point to the possible role of NO deficiency in the pathogenesis of renal lesions in aged SHR.