BACKGROUND/AIMS: Cholangiocytes are capable of reabsorbing bile salts from bile, but the pathophysiological significance of this process is unclear. To this end, we detected the expression and distribution of bile acid transport proteins in cholangiocytes from normal rat liver and analyzed the possible pathophysiological significance. METHODS: Bile duct tissues of Sprague-Dawley rats were isolated by enzymatic digestion and mechanical isolation, and then divided into large and small bile duct tissues. Immunohistochemistry, real-time polymerase chain reaction and Western blotting were used to determine the expression of the apical sodium-dependent bile acid transporter (ASBT), ileal bile acid binding protein (IBABP), and basolateral organic solute transporter α (Ostα) in the biliary tract system of rats. Differences in the expression and distribution of these proteins were analyzed. RESULTS: In cholangiocytes, ASBT and IBABP were mainly expressed in cholangiocytes of the large bile ducts, in which the expression of both was significantly higher than that in the small ducts (p<0.05). Ostα was simultaneously expressed in cholangiocytes of both the large and small bile ducts, showing no significant difference in expression between the two groups of bile ducts (p>0.05). CONCLUSIONS: Bile acid transporters are expressed and heterogeneously distributed in rat bile ducts, indicating that bile acid reabsorption by cholangiocytes might mainly occur in the large bile ducts. These findings may help explore the physiology of bile ducts and the pathogenesis of various cholangiopathies.
Animals ; Bile Acids and Salts ; Bile Ducts ; Bile ; Biliary Tract ; Blotting, Western ; Carrier Proteins ; Digestion ; Immunohistochemistry ; Liver ; Physiology ; Population Characteristics ; Rats ; Rats, Sprague-Dawley ; Real-Time Polymerase Chain Reaction

OBJECTIVE: This study aims to investigate whether dexamethasone (DEX) can down-regulate the PAR complex and disrupt the cell polarity in the palatal epithelium during palatal fusion. METHODS: Pregnant rats were randomly divided into control and DEX groups, which were injected intraperitoneally with 0.9% sodium chloride (0.1 mL) and DEX (6 mg·kg ⁻¹), respectively, every day from E10 to E12. The palatal epithelial morphology was observed using hematoxylin and eosin staining and scanning electron microscopy. Immunofluorescence staining, Western Blot analysis, and real-time polymerase chain reaction were performed to detect the expression of PAR3, PAR6, and aPKC. RESULTS: The incidence of cleft palate in DEX group (46.15%) was significantly higher than that in control group (3.92%), and the difference was statistically significant (χ2=24.335, P=0.00). DEX can also retard the growth of the palatal shelves and the short palatal shelves. The morphology and arrangement of MEE cells changed from polarized bilayer cells to nonpolarized monolayer ones. Additionally, the spherical structure decreased, which caused the cleft palate. PAR3 and PAR6 were only detected in the palatal epithelium, and aPKC was expressed in the palatal epithelium and mesenchyme. DEX can reduce the expression levels of PAR3, PAR6, and aPKC in the protein and gene levels. CONCLUSIONS DEX can down-regulate the complex gene expression in the MEE cells, thereby destroying the cell polarity and causing cleft palate.
Animals ; Carrier Proteins ; physiology ; Cell Polarity ; drug effects ; Cleft Palate ; etiology ; Dexamethasone ; pharmacology ; Epithelial Cells ; drug effects ; Female ; Glucocorticoids ; pharmacology ; Palate ; Pregnancy ; Rats

Animals ; Carrier Proteins ; genetics ; Immunohistochemistry ; Lacrimal Apparatus ; metabolism ; Lung ; metabolism ; Mice ; Mice, Inbred NOD ; Microfilament Proteins ; genetics ; RNA, Small Interfering ; genetics ; physiology ; Random Allocation ; Sjogren's Syndrome ; genetics ; immunology ; therapy

OBJECTIVETo study the expression and significance of the mammalian target of rapamycin (mTOR)/eukaryote initiating factor 4E binding protein 1(4EBP1)/hypoxia inducible factor-1α (HIF-1α)/vascular endothelial growth factor (VEGF) signaling pathway in asthmatic mice.

METHODSForty SPF level 6-8 week-old female Balb/C mice were randomly divided into control, asthma, budesonide and mTOR inhibitor (rapamycin) intervention groups (n=10 each). The asthmatic mouse model was prepared via OVA induction and challenge test. The intervention groups were administered with rapamycin at the dosage of 3 mg/kg by an intraperitoneal injection or budesonide suspension at the dosage of l mg by aerosol inhalation respectively 30 minutes before the OVA challenge. The control and asthma groups were treated with normal saline instead. The concentrations of HIF-1α and VEGF in bronchoalveolar lavage fluid (BALF) were examined using ELISA 24 hours after the last challenge. The pathological changes of lung tissue were observed by hematoxylin-eosin (HE) staining. The p-mTOR and p-4EBP1 from the lung tissues were detected by immunohistochemistry and Western blot. Pearson analysis was used to study the correlation between p-mTOR, p-4EBP1, HIF-1α, and VEGF expression.

RESULTSCompared with the control group, inflammatory cell infiltration and secretions in the trachea increased in the asthma group. The levels of HIF-1α and VEGF in BALF and p-mTOR and p-4EBP1 expression in lung tissues also increased (P<0.01). Compared with the asthma group, inflammatory cell infiltration and secretions in the trachea were reduced in the two intervention groups, and the levels of HIF-1α and VEGF in BALF and p-mTOR and p-4EBP1 expression in lung tissues were also reduced (P<0.01). There were no significant differences in the above changes between the two intervention groups and control group (P>0.05). In the asthma group, there was a pairwise positive correlation between lung p-mTOR and p-4EBP1 expression and HIF-1α and VEGF levels in BALF (P<0.05). However, there were no correlations in the above indexes in the intervention groups and control group.

CONCLUSIONSp-mTOR, p-4EBP1, HIF-1α and VEGF together are involved in the pathogenesis of asthma. Rapamycin treatment can block this signaling pathway, suggesting that this pathway can be used as a novel target for asthma treatment.

Animals ; Asthma ; drug therapy ; metabolism ; Carrier Proteins ; analysis ; physiology ; Female ; Hypoxia-Inducible Factor 1, alpha Subunit ; analysis ; physiology ; Lung ; chemistry ; pathology ; Mice ; Mice, Inbred BALB C ; Phosphoproteins ; analysis ; physiology ; Signal Transduction ; physiology ; TOR Serine-Threonine Kinases ; analysis ; physiology ; Vascular Endothelial Growth Factor A ; analysis ; physiology

Enterovirus 71 (EV71) is a neurotropic pathogen that can induce hand, foot and mouth disease in children. There is an appreciable mortality rate after EV71 infections. The mechanism of action of EV71 replication is not known. Recent work has identified some of cell factors of the host that participate in the synthesis of the RNA and proteins of EV71 (e.g., hnRNP K, reticulon 3 (RTN 3)). In that work, researchers used a competitive assay to show that hnRNP K can interact with EV71 5' UTR, which is required for efficient synthesis of viral RNA. Using a yeast two-hybrid system, other researchers demonstrated that RTN 3 interacts with the N-terminal domain of EV71 2C, which is crucial for replication of viral RNA. Here, we discuss recent work focusing on the molecular mechanisms of hnRNP K and RTN 3 in the synthesis of the RNA and proteins of EV71.
Animals ; Carrier Proteins ; genetics ; metabolism ; Enterovirus A, Human ; genetics ; physiology ; Enterovirus Infections ; genetics ; metabolism ; virology ; Heterogeneous-Nuclear Ribonucleoprotein K ; Host-Pathogen Interactions ; Humans ; Membrane Proteins ; genetics ; metabolism ; Nerve Tissue Proteins ; genetics ; metabolism ; Ribonucleoproteins ; genetics ; metabolism ; Viral Proteins ; genetics ; metabolism ; Virus Replication

OBJECTIVETo explore the effect of the cytoplasmic DNA sensor DAI on replication of hepatitis B virus (HBV) and its possible mechanism.

METHODSThe hepatocyte-derived cell line HepG2 was co-transfected with DAI siRNA and the HBV1.3 replicative plasmid PHY106, and the cells were divided into two experimental groups. Six hours later, total RNA was extracted from the first group of cells and expression of IFIT1 and IL-6 were detected by real-time RT-PCR. The second group of cells was incubated for 4 days, after which the cell supernatant was collected and the HBV surface antigen (HBsAg) and envelope antigen (HBeAg) were detected by ELISA. In addition, HBV core particles were extracted and applied to southern blot assay to detect the intracellular HBV replication intermediates (rcDNA, dlDNA and ssDNA). Next, the HepG2 cells were triple transfected with siRNA targeting the type I interferon pathway molecule TBK1 and DAI simultaneously and HBV1.3, after which HBV viral proteins were detected. Two-group comparisons were made using the independent sample t-test, and more-than-2-group comparisons were made using ANOVA.

RESULTSDAI gene expression was down-regulated in response to DAI siRNA transfection. Cells with down-regulated DAI showed inhibited HBV replication (in a dose-dependent manner), accompanied by reduced levels of HBsAg (0.0195+/-0.0050 vs.

CONTROL0.3150+/-0.0200, P less than 0.05, t = 14.77) and HBeAg (0.0140+/-0.0040 vs.

CONTROL0.01235+/-0.0135, P less than 0.05, t = 7.777). No effect of down-regulated DAI was observed for the expression of IFIT1 of IL-6. siRNA-mediated down-regulation of TBK1 and DAI simultaneously led to reduced expression of HBsAg and HBeAg.

CONCLUSIONDown-regulation of DAI gene expression inhibited HBV replication and HBV protein expression, but the underlying mechanism was not related to the type I interferon or NF-kB signaling pathway.

Carrier Proteins ; metabolism ; DNA-Binding Proteins ; genetics ; metabolism ; Down-Regulation ; Gene Expression Regulation ; Hep G2 Cells ; Hepatitis B Surface Antigens ; isolation & purification ; Hepatitis B e Antigens ; isolation & purification ; Hepatitis B virus ; physiology ; Humans ; Interleukin-6 ; metabolism ; NF-kappa B ; metabolism ; Plasmids ; RNA, Small Interfering ; genetics ; Signal Transduction ; Transfection ; Virus Replication

BACKGROUND: We investigated the rates of fecal transmission of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae (ESBL-E) and carbapenem-resistant Enterobacteriaceae (CRE) among patients admitted to intensive care units (ICUs). METHODS: From June to August 2012, rectal cultures were acquired from all patients at ICU admission. For patients not carrying ESBL-E or CRE at admission, follow-up cultures were performed to detect acquisition. A chromogenic assay was used to screen for ESBL-E and CRE. Bacterial species identification and antibiotic susceptibility tests were performed using the Vitek 2 system (bioMerieux, France). ESBL genotypes were determined by PCR, and clonal relatedness of the isolates was assessed by pulsed-field gel electrophoresis. RESULTS: Out of 347 ICU admissions, 98 patients were found to be carriers of ESBL-E (28.2%, 98/347). Follow-up cultures were acquired from 91 of the patients who tested negative for ESBL-E at admission; the acquisition rate in this group was 12.1% (11/91), although none was a nosocomial transmission. For CRE, the prevalence of fecal carriage was 0.3% (1/347), and the acquisition rate was 2.9% (4/140). None of the CRE isolates were carbapenemase-producers. CONCLUSIONS: The high prevalence of ESBL-E carriage on admission (28.2%), coupled with rare nosocomial transmission and the very low carriage rate of CRE (0.3%), challenge the routine use of active surveillance in non-epidemic settings. Nevertheless, passive surveillance measures, such as rapid and accurate screening of clinical specimens, will be critical for controlling the spread of CRE.
Anti-Bacterial Agents/pharmacology ; Bacterial Proteins/*metabolism ; Carbapenems/*pharmacology ; Carrier State/epidemiology ; Cross Infection/epidemiology/*transmission ; DNA, Bacterial/analysis ; Drug Resistance, Bacterial/drug effects ; Electrophoresis, Gel, Pulsed-Field ; Enterobacteriaceae/enzymology/genetics/*physiology ; Enterobacteriaceae Infections/epidemiology/*transmission ; Feces/*microbiology ; Genotype ; Humans ; Intensive Care Units ; Polymerase Chain Reaction ; Prevalence ; Republic of Korea/epidemiology ; beta-Lactamases/*metabolism

Vitamin D3 up-regulated protein 1 (VDUP1) is a potent growth suppressor that inhibits tumor cell proliferation and cell cycle progression when overexpressed. In a previous study, we showed that VDUP1 knockout (KO) mice exhibited accelerated liver regeneration because such animals could effectively control the expression of cell cycle regulators that drive the G1-to-S phase progression. In the present study, we further investigated the role played by VDUP1 in initial priming of liver regeneration. To accomplish this, VDUP1 KO and wild-type (WT) mice were subjected to 70% partial hepatectomy (PH) and sacrificed at different times after surgery. The hepatic levels of TNF-alpha and IL-6 increased after PH, but there were no significant differences between VDUP1 KO and WT mice. Nuclear factor-kappaB (NF-kappaB), c-Jun-N-terminal kinase (JNK), and signal transducer and activator of transcription 3 (STAT-3) were activated much earlier and to a greater extent in VDUP1 KO mice after PH. A single injection of TNF-alpha or IL-6 caused rapid activation of JNK and STAT-3 expression in both mice, but the responses were stronger and more sustained in VDUP1 KO mice. In conclusion, our findings provide evidence that VDUP1 plays a role in initiation of liver regeneration.
Animals ; Blotting, Western ; Carrier Proteins/*genetics/metabolism ; Cell Proliferation ; *Gene Expression Regulation ; Hepatectomy ; Hepatocytes/*cytology/physiology ; JNK Mitogen-Activated Protein Kinases/genetics/metabolism ; Liver/*physiology ; Male ; Mice, Knockout ; NF-kappa B/genetics/metabolism ; Polymerase Chain Reaction ; *Regeneration ; STAT3 Transcription Factor/genetics/metabolism ; Thioredoxins/*genetics/metabolism

Ebola virus can cause severe Ebola hemorrhagic fever. The mortality rate is 90 percent. Up till now, there is no effective vaccine or treatment of Ebola virus infection. Relaed researches on Ebola virus have become a hot topic in virology. The understanding of molecular mechanisms of Ebola virus infection of cells are important for the development of vaccine and anti-virus drugs. Therefore, this review summarized the recent research progress on the mechanisms of Ebola virus infection.
Carrier Proteins ; physiology ; Ebolavirus ; pathogenicity ; Hemorrhagic Fever, Ebola ; etiology ; Humans ; Membrane Fusion ; Membrane Glycoproteins ; physiology ; Pinocytosis

OBJECTIVETo review the mechanisms by which HIV evades different components of the host immune system.

DATA SOURCESThis review is based on data obtained from published articles from 1991 to 2012. To perform the PubMed literature search, the following key words were input: HIV and immune evasion.

STUDY SELECTIONArticles containing information related to HIV immune evasion were selected.

RESULTSAlthough HIV is able to induce vigorous antiviral immune responses, viral replication cannot be fully controlled, and neither pre-existing infected cells nor latent HIV infection can be completely eradicated. Like many other enveloped viruses, HIV can escape recognition by the innate and adaptive immune systems. Recent findings have demonstrated that HIV can also successfully evade host restriction factors, the components of intrinsic immune system, such as APOBEC3G (apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like 3G), TRIM5α (tripartite motif 5-α), tetherin, and SAMHD1 (SAM-domain HD-domain containing protein).

CONCLUSIONSHIV immune evasion plays an important role in HIV pathogenesis. Fully understanding the tactics deployed by HIV to evade various components of the host immune systems will allow for the development of novel strategies aimed toward the prevention and cure of HIV/AIDS.

APOBEC-3G Deaminase ; Adaptive Immunity ; Antibodies, Neutralizing ; immunology ; Antigens, CD ; physiology ; Carrier Proteins ; physiology ; Complement System Proteins ; immunology ; Cytidine Deaminase ; physiology ; GPI-Linked Proteins ; physiology ; HIV-1 ; immunology ; Humans ; Immune Evasion ; Killer Cells, Natural ; immunology ; Monomeric GTP-Binding Proteins ; physiology ; SAM Domain and HD Domain-Containing Protein 1