OBJECTIVES: Helicobacter pylori infection induces selective reduction of the number of antral D-cells and results in abnormal regulation of serum gastrin secretion. The purpose of this study was to investigate the relationship between H. pylori infection and the numbers of G-cells and D-cells. METHODS: The numbers of antral G-cells and D-cells, the ratio of G-cells to D-cells and fasting serum gastrin concentrations were compared between 37 patients with (29 with duodenal ulcers and 8 with gastric ulcers) and 33 without H. pylori infection (22 with duodenal ulcers and 11 with gastric ulcers). Serum gastrin concentrations were measured using the radioimmunoassay technique. Antral mucosal biopsy specimens were examined using immunohistochemical staining with antibodies specific for gastrin and somatostatin and the numbers of G-cells and D-cells per gastric gland were counted. RESULTS: Fasting serum gastrin concentrations were significantly higher in patients with H. pylori infection compared to patients without infection (80.3 +/- 23.5 vs 47.6 +/- 14.1 pg/ml, p < 0.001). The number of G-cells per gastric gland was similar in infected and uninfected patients (7.1 +/- 3.1 vs 7.3 +/- 3.9, respectively, p > 0.5). The number of D-cells was significantly lower in patients with H. pylori infection than in uninfected patients in both duodenal and gastric ulcer patients (1.3 +/- 0.4 vs 2.5 +/- 1.6, respectively, p < 0.001). The ratio of G-cells to D-cells was also significantly higher in infected patients compared with uninfected patients for both gastric and duodenal ulcers (5.7 +/- 2.7 vs 3.5 +/- 1.9, respectively, p < 0.001). CONCLUSIONS: These results strongly suggest that Helicobacter pylori infection induces reduction of the number of antral D-cells. The resulting relative hypofunction of the inhibitory action of D-cells against G-cells may be responsible for increased serum gastrin secretion.
Case-Control Studies ; D Cells/pathology ; D Cells/metabolism ; G Cells/pathology ; G Cells/metabolism ; Gastrins/metabolism ; Gastrins/blood ; Gastritis/pathology ; Gastritis/metabolism* ; Helicobacter Infections/pathology ; Helicobacter Infections/metabolism* ; Helicobacter pylori* ; Human ; Somatostatin/metabolism

OBJECTIVETo analyze the clinicopathologic features of chronic sclerosing submaxillaritis (CSS).

METHODSThe clinical and pathological characteristics of 9 CSS were analyzed.

RESULTSIn the 9 patients, there were 6 males and 3 females. The age of patients ranged from 51 - 77 years old. All of the tumors were located in the submandibular gland, presenting with painless and firm mass. Histologically, a well-defined mass lesion with extensive lymphocytes and plasma cells infiltration, preservation of lobular architecture, with acinar atrophy. The reactive hyperplasia of lymphoid follicles may be found in CSS. The phlebitis and obliterating phlebitis also formed. Immunohistochemistry showed evidence of diffuse infiltration of plasma cells. The mean number of IgG4-positive plasma cell per high-power field (HPF) was 186, mean value of the IgG4:IgG ratio was 0.71. Three of these 9 cases had manifestations of IgG4-associated systemic disease.

CONCLUSIONSCSS is considered as a part of IgG4-related sclerosing diseases, recognition of which is very essential for a successful treatment. When diagnosis is made, it is necessary to ascertain whether lesion occurs within salivary gland only or in combination with outside IgG4-related sclerosing disease. The establishment of follow-up is also necessary. Some patients show good response to steroid therapy.

Aged ; Female ; Humans ; Immunoglobulin G ; metabolism ; Male ; Middle Aged ; Plasma Cells ; immunology ; Sclerosis ; Sialadenitis ; metabolism ; surgery ; Submandibular Gland ; pathology ; surgery

Heterotrimeric guanine nucleotide binding regulatory proteins (G proteins) transduce extracellular signals into intracellular signals by coupling receptors and effectors. Because most of the G protein-coupled receptors are integral proteins, the G proteins need to have a membrane binding capacity to receive signals from the receptors. The alpha subunit of G protein binds tightly to the cytoplasmic face of the plasma membrane without any membrane spanning domain. Fatty acylation of G alpha with myristic acid or palmitic acid, in addition to the beta gamma subunits, plays an important role in anchoring the G alpha subunit. The reversible and dynamic palmitoylation of the alpha subunit of stimulatory G protein (Gs alpha) has been suggested as essential for its membrane attachment. However, in our previous experiments, Gs alpha deleted in the amino terminus containing palmitoylation site, retained its binding capacity when expressed in COS cells. Thus, to evaluate the role of palmitoylation in Gs alpha membrane binding, we constructed and expressed non-palmitoylated mutants of Gs alpha and analyzed their subcellular distributions in COS-1 cells. We found that non-palmitoylated mutants of Gs alpha, C3S- and G2A/C3S Gs alpha, retained their membrane binding capacities in COS-1 cells, demonstrating that palmitoylation is not essential for membrane binding of Gs alpha in COS-1 cells. We also found that the palmitoylation did not change significantly the distribution of Gs alpha in Triton X-114 partition. These results suggest that the palmitoylation of Gs alpha may produce different effects on membrane binding depending on cell types.
Animal ; Blotting, Western ; COS Cells ; Cell Membrane/metabolism ; Detergents/pharmacology ; G-Protein, Stimulatory Gs/metabolism* ; G-Protein, Stimulatory Gs/genetics ; Immunoblotting ; Isoproterenol/metabolism ; Mutagenesis ; Palmitates/metabolism* ; Polyethylene Glycols/pharmacology ; Rats ; Transfection

OBJECTIVETo explore the role of platelet-activating factor receptor (PAFR) in adhesion and invasion of phospho- rylcholine (PC)-positive Aggregatibacter actinomycetemcomitans in cultured human umbilical vein endothelial cells (HUVEC).

METHDOSCultured HUVECs were pretreated with the PAFR antagonist CV3988 or anti-human PAFR monoclonal antibody for 30 min before infection with PC-positive or -negative A. actinomycetemcomitans strains. The bacterial adhesion and invasion and cytotoxicity in the cells were examined using MTT assay.

RESULTSPretreatment with PAFR antagonists at 100, 200 and 500 nmol/L significantly reduced the adhesion rate (36.29∓3.52)%, (19.04∓3.35)% and (7.69∓3.19%), respectively] and invasion rate [(12.12∓1.58)%, (7.08∓0.29)% and (2.60∓2.26)%, respectively] of PC-positive A.actinomycetemcomitans in HUVECs. Similarly, pretreatment with anti-PAFR antibody also significantly reduced A.actinomycetemcomitans adhesion and invasion in HUVECs [(50.05∓5.28)% and (39.09∓6.50)%, respectively]. Pretreatment with PAFR antagonist (200 and 500 nmol/L) and anti-PAFR antibody (25 µg/mL) significantly increased the viability of HUVECs incubated with PC-positive A.actinomycetemcomitans from (25.39∓9.33)% to (91.12∓3.14)%, (94.12∓2.15)% and (65.5∓1.87)%, respectively, but such pretreatments did not increase the viability of cells incubated with PC-negative A.actinomycetemcomitans.

CONCLUSIONSPAFR plays an important role in the adhesion, invasion, and cytotoxicity of PC-positive A.actinomycetemcomitans in cultured HUVECs.

Aggregatibacter actinomycetemcomitans ; pathogenicity ; Bacterial Adhesion ; Cells, Cultured ; Human Umbilical Vein Endothelial Cells ; microbiology ; Humans ; Platelet Membrane Glycoproteins ; metabolism ; Receptors, G-Protein-Coupled ; metabolism

This study was aimed to investigate the growth inhibition effect of diimide G-quadruplex ligand on leukemia cells and to explore its molecular mechanisms. K562 leukemia cell lines were treated with various concentrations of the diimide G-quadruples ligand small molecule (0.1 - 10 micromol/L). Trypan blue exclusion assay was used to evaluate the proliferation inhibition. Cell apoptosis was observed using terminal deoxynucleotide transferase-mediated dUTP nick end labeling (TUNEL). Telomerase activity was analyzed by telomere repeat amplification protocol. Gene expression was detected by microarray and confirmed by RT-PCR assay. The results showed that diimide small molecule inhibited the proliferation of K562 cells and induced apoptosis of these cells. After treating with diimide G-quadruplex ligand, telomerase activity of K562 cells was reduced and the transcriptional levels of some important genes were changed significantly. These genes were involved in cell apoptosis, cell signaling pathway and other key functions. In conclusion, the diimide G-quadruplex ligand is a small molecule that inhibits the proliferation and induces apoptosis in leukemia cells, and these functions may be related to telomerase inhibition and regulation of some important gene transcription.
Apoptosis ; drug effects ; Cell Proliferation ; drug effects ; G-Quadruplexes ; Humans ; K562 Cells ; Leukemia ; genetics ; pathology ; Ligands ; Microarray Analysis ; Telomerase ; metabolism

Immunoglobulin (IgG) glycosylation affects the effector functions of IgG in a myriad of biological processes and has been closely associated with numerous autoimmune diseases, including systemic lupus erythematosus (SLE), thus underlining the pathogenic role of glycosylation aberration in autoimmunity. This study aims to explore the relationship between IgG sialylation patterns and lupus pregnancy. Relative to that in serum samples from the control cohort, IgG sialylation level was aberrantly downregulated in serum samples from the SLE cohort at four stages (from preconception to the third trimester of pregnancy) and was significantly associated with lupus activity and fetal loss during lupus pregnancy. The type I interferon signature of pregnant patients with SLE was negatively correlated with the level of IgG sialylation. The lack of sialylation dampened the ability of IgG to suppress the functions of plasmacytoid dendritic cells (pDCs). RNA-seq analysis further revealed that the expression of genes associated with the spleen tyrosine kinase (SYK) signaling pathway significantly differed between IgG- and deSia-IgG-treated pDCs. This finding was confirmed by the attenuation of the ability to phosphorylate SYK and BLNK in deSia-IgG. Finally, the coculture of pDCs isolated from pregnant patients with SLE with IgG/deSia-IgG demonstrated the sialylation-dependent anti-inflammatory function of IgG. Our findings suggested that IgG influences lupus activity through regulating pDCs function via the modulation of the SYK pathway in a sialic acid-dependent manner.
Humans ; Pregnancy ; Female ; Lupus Erythematosus, Systemic/pathology* ; Signal Transduction ; N-Acetylneuraminic Acid/metabolism* ; Immunoglobulin G ; Dendritic Cells/pathology*

The characteristics of virus-like particle (VLP) of JC virus (JCV) as a vector for targeting gene delivery was determined. The exogenous DNA (PUC19) packaged in VLP-Z was resistant to DNase I. VLP-Z was able to deliver a reporter plasmid pEGFP-N1 into HeLa cells and the green fluorescent reporter protein was expressed in these cells. VLP-Z was also able to bind IgG by interaction with the Z fragment of VLP-Z and IgG. These results suggested that VLP-Z might be used as a vector to deliver therapeutic genes to target cells with incorporating IgG antibodies.
Gene Targeting ; methods ; Gene Transfer Techniques ; Genetic Therapy ; methods ; Genetic Vectors ; genetics ; HeLa Cells ; Humans ; Immunoglobulin G ; metabolism ; JC Virus ; genetics ; metabolism ; Virion ; genetics ; metabolism

FGF21 (fibroblast growth factor 21) is a recently described member of the FGF family. It has been previously demonstrated that FGF21 is a potent regulator of glucose homeostasis. To improve stability of FGF21 for better efficacy, a new form of recombinant FGF21 was generated by fusion of a full length FGF21 gene and the Fc fragment of human IgG4 with flexible linker sequence. To examine the glucose regulation activity of FGF21-L-Fc, 3T3-L1 pre-adipocytes were differentiated into adipocytes, and glucose uptake activity of FGF21-L-Fc was examined by glucose oxidase and peroxidase (GOD-POD) assay. The results showed that in comparison with wild type FGF21, FGF21-L-Fc was more potent in stimulation of glucose uptake by 3T3-L1. In vivo studies on the modified protein demonstrated that FGF-L-Fc had a better efficacy in lowering blood glucose of the STZ-induced diabetic animals and controlled glucose level for a longer time. The results provided a sound basis for further studies.
3T3-L1 Cells ; Adipocytes ; metabolism ; Animals ; Blood Glucose ; metabolism ; Diabetes Mellitus, Experimental ; drug therapy ; metabolism ; Escherichia coli ; metabolism ; Fibroblast Growth Factors ; genetics ; pharmacology ; Glucose ; metabolism ; Immunoglobulin G ; genetics ; pharmacology ; Male ; Mice ; Recombinant Proteins ; genetics ; pharmacology

We recently reported the use of a gene-trapping approach to isolate cell clones in which a reporter gene had integrated into genes modulated by T-cell activation. We have now tested a panel of clones from that report and identified the one that responds to a variety of G-protein coupled receptors (GPCR). The beta-lactamase tagged EGR-3 Jurkat cell was used to dissect specific GPCR signaling in vivo. Three GPCRs were studied, including the chemokine receptor CXCR4 (Gi-coupled) that was endogenously expressed, the platelet activation factor (PAF) receptor (Gq-coupled), and beta2 adrenergic receptor (Gs-coupled) that was both stably transfected. Agonists for each receptor activated transcription of the beta-lactamase tagged EGR-3 gene. Induction of EGR-3 through CXCR4 was blocked by pertussis toxin and PD58059, a specific inhibitor of MEK (MAPK/ERK kinase). Neither of these inhibitors blocked isoproterenol or PAF-mediated activation of EGR-3. Conversely, beta2- and PAF-mediated EGR-3 activation was blocked by the p38, specific inhibitor SB580. In addition, both beta2- and PAF-mediated EGR-3 activation could be synergistically activated by CXCR4 activation. This combined result indicates that EGR-3 can be activated through distinct signal transduction pathways by different GPCRs and that signals can be integrated and amplified to efficiently tune the level of activation.
Culture Media ; DNA-Binding Proteins ; metabolism ; Early Growth Response Protein 3 ; Gene Expression Regulation ; Genes, Reporter ; Humans ; Jurkat Cells ; MAP Kinase Signaling System ; Receptors, CXCR4 ; metabolism ; Receptors, G-Protein-Coupled ; metabolism ; Signal Transduction ; Transcription Factors ; metabolism ; beta-Lactamases ; metabolism

Mitofusin2 (Mfn2) plays a pivotal role in the proliferation and apoptosis of vascular smooth muscle cells (VSMCs). The purpose of this study was to investigate the effects of Mfn2 on the trafficking of intracellular cholesterol in the foam cells derived from rat VSMCs (rVSMCs) and also to investigate the effects of Mfn2 on the expression of adenosine triphosphate-binding cassette subfamily A member 1 (ABCA1), adenosine triphosphate-binding cassette subfamily G member 1 (ABCG1) and peroxisome proliferator-activated receptor gamma (PPARγ). The rVSMCs were co-cultured with oxidized low density lipoprotein (LDL, 80 μg/mL) to produce foam cells and cholesterol accumulation in cells. Before oxidized LDL treatment, different titers (20, 40 and 60 pfu/cell) of recombinant adenovirus containing Mfn2 gene (Adv-Mfn2) were added into the culture medium for 24 h to transfect the Mfn2 gene into the rVSMCs. Then the cells were harvested for analyses. The protein expression of Mfn2 was significantly higher in Adv-Mfn2-transfected group than in untransfected group (P<0.05), and the expression levels significantly increased when the titer of Adv-Mfn2 increased (P<0.05). At 24 or 48 h after oxidized LDL treatment, rVSMCs became irregular and their nuclei became larger, and their plasma abounded with red lipid droplets. However, the number of red lipid droplets was significantly decreased in Adv-Mfn2-transfected group as compared with untransfected group. At 48 h after oxidized LDL treatment, the intracellular cholesterol in rVSMCs was significantly increased (P<0.05), but it was significantly decreased in Adv-Mfn2-transfected group as compared with untransfected group (P<0.05), and it also significantly decreased when the titer of Adv-Mfn2 increased (P<0.05). The mRNA and protein expression levels of ABCA1 and ABCG1 were significantly increased in Adv-Mfn2-transfected group as compared with untransfected group (P<0.05). Though the mRNA and protein expression levels of PPARγ was not significantly increased (P>0.05), the phosporylation levels of PPARγ were significantly decreased in Adv-Mfn2-transfected group as compared with untransfected group (P<0.05). These results suggest that the transfection of Adv-Mfn2 can significantly reduce intracellular cholesterol in oxidized LDL-induced rVSMCs possibly by decreasing PPARγ phosporylation and then increasing protein expression levels of ABCA1 and ABCG1, which may be helpful to suppress the formation of foam cells.
ATP Binding Cassette Transporter 1 ; metabolism ; ATP Binding Cassette Transporter, Sub-Family G, Member 1 ; ATP-Binding Cassette Transporters ; metabolism ; Animals ; Cell Differentiation ; physiology ; Cells, Cultured ; Cholesterol ; metabolism ; Foam Cells ; cytology ; metabolism ; Intracellular Fluid ; metabolism ; Lipoproteins, LDL ; metabolism ; Membrane Proteins ; genetics ; metabolism ; Mitochondrial Proteins ; genetics ; metabolism ; Muscle, Smooth, Vascular ; cytology ; metabolism ; Oxidation-Reduction ; PPAR gamma ; metabolism ; Rats