[Standardized screening and early imaging diagnosis strategies for hepatocellular carcinoma].

Standardized hepatocellular carcinoma (HCC) screening is very important for early diagnosis. Chinese and international HCC clinical guidelines recommend regular ultrasound screening for high-risk patients. Noninvasive dynamic enhanced imaging technology should be selected for the positive screenin population to get the further diagnosis, including contrast-enhanced ultrasound (CEUS), dynamic contrast-enhanced CT, dynamic contrast-enhanced MRI and Gd-EOB-DTPA enhanced MRI (EOB MRI). In clinical practice, early diagnose of HCC relies on accurate identification and stratification of high-risk patients, and systematic approach based on dynamic contrast-enhanced imaging.

Antibiofilm activity of three Actinomycete strains against Staphylococcus epidermidis.

This study sought to identify novel and nontoxic biofilm inhibitors from the Actinomycete library for attenuating biofilm formation by Staphylococcus epidermidis. After investigating the antibiofilm activities of spent media from 185 Actinomycete strains using two S. epidermidis strains (ATCC 35984 and a clinical strain 5-121-2) as target bacteria, three strains of tested Actinomycete (TRM 46200, TRM 41337, and TRM 46814) showed a significant inhibition against S. epidermidis biofilm formation without affecting the growth of planktonic cells. The characteristics of three strains of supernatants suggested that hydrophilic compound possibly extracellular peptides or proteins from these three strains, confer the biofilm reduction in S. epidermidis. An attempt was made to assess their effects on biofilm components and cell surface hydrophobicities in order to disclose acting mechanisms. The crude proteins from spent media of three strains degraded not only exopolysaccharides but also extracellular DNA in S. epidermidis biofilm. The active substances in crude proteins caused S. epidermidis cells to become less hydrophobic. Given these results, the metabolites from Actinomycete strains should keep further attention as potential antibiofilm agents against biofilm formation of S. epidermidis, even biofilm infections of the other bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: Staphylococcus epidermidis infections are frequently associated with biofilms that are difficult to eradicate with conventional antibiotics. The new biofilm inhibitors from Actinomycete will have a great value in the prevention and treatment of dairy cow mastitis and other biofilm-related infections.

The Cardioprotective Effects of Late-Phase Remote Preconditioning of Trauma Depends on Neurogenic Pathways and the Activation of PKC and NF-κB (But Not iNOS) in Mice.

BACKGROUND: A superficial abdominal surgical incision elicits cardioprotection against cardiac ischemia-reperfusion (I/R) injury in mice. This process, called remote preconditioning of trauma (RPCT), has both an early and a late phase. Previous investigations have demonstrated that early RPCT reduces cardiac infarct size by 80% to 85%. We evaluated the cardioprotective and molecular mechanisms of late-phase RPCT in a murine I/R injury model. METHODS: Wild-type mice, bradykinin (BK) 2 receptor knockout mice, 3M transgenic mice (nuclear factor κB [NF-κb] repressor inhibitor of nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha [IκBα((S32A, S36A, Y42F))]), and inducible nitric oxide synthase (iNOS) knockout mice were analyzed using a previously established I/R injury model. A noninvasive abdominal surgical incision was made 24 hours prior to I/R injury and the infarct size was determined at 24 hours post-I/R injury. RESULTS: The results indicated that a strong cardioprotective effect occurred during late-phase RPCT (58.42% ± 1.89% sham vs 29.41% ± 4.00% late RPCT, mean area of the infarct divided by the mean area of the risk region; P ≤ .05; n = 10). Furthermore, pharmacological intervention revealed the involvement of neurogenic signaling in the beneficial effects of late RPCT via sensory and sympathetic thoracic nerves. Pharmacological experiments in transgenic mice-implicated BK receptors, ß-adrenergic receptors, protein kinase C, and NF-κB but not iNOS signaling in the cardioprotective effects of late RPCT. CONCLUSION: Late RPCT significantly decreased myocardial infarct size via neurogenic transmission and various other signaling pathways. This protective mechanism differentiates late and early RPCT. This study describes a new cardiac I/R injury prevention method and refines the concept of RPCT.

Expression of recombinant BMP-7 gene increased ossification activity in the rabbit bone mesenchymal stem cells.

OBJECTIVE: The mesenchymal stem cells (MSCs), which were distributed in the bone marrow stroma, become ideal progenitor cells in bone tissue engineering because of their convenient isolation, small injury when obtained, and strong osteogenic capacity. The osteogenic differentiation of MSCs, which is indicated by the increased alkaline phosphatase (ALP) activity and the enhanced accumulation of collagen, could be induced by a strong osteogenic capacity biological factor termed bone morphogenetic protein-7 (BMP-7). Although the chemically synthesized BMP-7 was widely applied to study the osteogenic differentiation of MSCs, transferring and expressing BMP-7 gene in target cells is more desirable, especially for gene therapy, given the advantages and convenience on the stable expression of BMP-7. The aim of this study was to determine whether recombinant BMP-7-expressing MSCs would induce bone formation in vitro. MATERIALS AND METHODS: BMP-7 gene was cloned from human placental tissue to construct a recombinant eukaryotic expression plasmid carrying BMP-7 gene by conjugating with eukaryotic expression vector pcDNA3.1. MSCs were isolated from rabbit bone marrow and cultured in vitro. Then they were divided into 3 groups: pcDNA3.1-BMP-7-transfected, pcDNA3.1-transfected, and untransfected. Human healthy fresh placental tissue was provided by the Department of Gynaecology and Obstetrics, Second Affiliated Hospital of Harbin Medical University. Written informed consent was obtained from the women. One healthy male New Zealand rabbit was provided by the Laboratory Animal Center, Harbin Medical University. RESULTS: A significant increase of ALP activity was detected in the supernatant of pcDNA3.1-BMP-7 transfected MSCs, and the enhanced collagen accumulation, which was inferred by the increased hydroxyproline content and RT-PCR. CONCLUSIONS: These results implied that BMP-7 gene was expressed in MSCs sufficiently and was involved in inducing differentiation of MSCs into osteoblast.

Down-regulation of microRNA-205 promotes gastric cancer cell proliferation.

OBJECTIVE: Increasing evidence indicates that MicroRNAs, a class of small RNA molecules, play crucial roles in tumorigenesis, through affecting cell proliferation, apoptosis and metastasis. The present study aimed to investigate the effect of miR-205 on gastric cancer cell proliferation. MATERIALS AND METHODS: The expression of miR-205 was examined in the gastric cancer tissues and cell lines. BrdU incorporation assay was used to measure the cell proliferation. Western blot was performed to determine the protein expression. RESULTS: miR-205 is significantly down-regulated in gastric cancer tissues, compared with adjacent normal tissues. Besides, miR-205 expression is associated with clinical and pathological characteristics of patients. In vitro studies further found that inhibition of miR-205 significantly promoted gastric cancer cell proliferation via cell-cycle progression. Further analyses indicated that miR-205 was able to repress oncoprotein Yin Yang 1 expression, through targeting its 3'-untranlated region. CONCLUSIONS: Our data suggest that down-regulation of miR-205 may represent an important mechanism for the development of gastric cancer.