Laser therapy accelerates initial attachment and subsequent behaviour of human oral fibroblasts cultured on titanium implant material. A scanning electron microscope and histomorphometric analysis

The aim of the study was to investigate the effect of low-level laser therapy (LLLT) on attachment and proliferation of human gingival fibroblasts (HGF) cultured on titanium implant material. HGF were exposed to gallium-aluminum-arsenide diode laser at dosages of 1.5 or 3 J/cm(2) and then cultured on commercially pure titanium discs. Cell profile areas were measured after 1, 3 and 24 h, using scanning electron microscopy and an automatic image analyzer. The results were expressed as percentage of attachment. In order to investigate the effect of LLLT on cellular growth after 8 and 10 days, HGF were cultured on titanium discs for 24 h and then exposed to laser irradiation on 3 consecutive days. Colony-forming efficiency (CFE) and clonal growth rates (CGR) were measured. Cell viability was determined by Hoechst and prodidium iodide staining. Non-lased cultures served as controls. Morphologically, the cells spread well on all titanium surfaces, indicating good attachment by both irradiated and non-irradiated cells. Fibroblasts exposed to laser irradiation had significantly higher percentages of cell attachment than the non-exposed cells (P<0.05). CFE and CGR were also enhanced for the irradiated cells (P<0.05). Cell viability was high (>90%) in the irradiated and control groups, without significant differences. It is concluded that in vitro LLLT enhances the attachment and proliferation of HGF on titanium implant material.     

Radiological treatment of retained bile duct stones following recent surgery using glucagons

BACKGROUND: Retained common bile duct (CBD) stones pose an occasional problem following ductal exploration, in spite of completion cholangiography or choledochoscopy. We present a method for treating retained stones in the Radiology Department by biliary lavage via a transcystic tube (TCT) or a T-tube, after intravenous administration of glucagon. METHODS: A TCT or T-tube is inserted following CBD exploration for multiple intrahepatic stones or when stones are fragmented to facilitate removal or flushing into the duodenum. A tube cholangiogram is performed on the 1st postoperative day. If any retained stones are encountered, 1 mg glucagon is administered intravenously and saline irrigation through the tube is done under fluoroscopic control, allowing the stone to pass to the duodenum. The cholangiogram is repeated 10-14 days later, before removing the tube. RESULTS: In case 1, transcystic CBD exploration was performed. Two stones were crushed and flushed into the duodenum. TCT cholangiography the following day. showed a 5-6-mm fragment causing complete obstruction. Following the use of glucagon and irrigation, the stone was observed passing into the duodenum, causing a brief mild episode of pain. In case 2, laparoscopic choledochotomy was performed to remove seven large stones. Completion choledochoscopy was satisfactory. T-tube cholangiography identified a small stone in the CBD, which was cleared with the help of glucagon. CONCLUSION: The current standard treatment for retained stones is endoscopic sphincterotomy. This is associated with morbidity, mortality, and significant additional cost. This new technique is a simple and safe alternative for retained CBD stones, most of which as small stones or fragments. Because glucagon causes intense relaxation of the sphincter of Oddi, the procedure should not take much longer than a routine tube cholangiogram. The safety of glucagon makes it possible to repeat the procedure if necessary.     

Inhibition of carcinoma cell motility by epoxyeicosatrienoic acid (EET) antagonists

Cytochrome P450 (CYP) epoxygenases, CYP2C8, 2C9 and 2J2 mRNA and proteins, were expressed in prostate carcinoma (PC‐3, DU‐145 and LNCaP) cells. 11,12‐Epoxyeicosatrienoic acid (11,12‐EET) was the major arachidonic acid metabolite in these cells. Blocking EET synthesis by a selective CYP epoxygenase inhibitor (N‐methylsulfonyl‐6‐(2‐propargyloxyphenyl)hexanamide [MS‐PPOH]) inhibited tonic (basal) invasion and migration (motility) while exogenously added EET induced cell motility in a concentration‐dependent manner. An epidermal growth factor receptor (EGFR) kinase inhibitor (AG494) or a PI3 kinase inhibitor (LY294002) inhibited cell migration and reduced 11,12‐EET‐induced cell migration. Importantly, synthetic EET antagonists (14,15‐epoxyeicosa‐5(Z)‐enoic acid [14,15‐EEZE], 14,15‐epoxyeicosa‐5(Z)‐enoic acid 2‐[2‐(3‐hydroxy‐propoxy)‐ethoxy]‐ethyl ester [14,15‐EEZE‐PEG] and 14,15‐epoxyeicosa‐5(Z)‐enoic‐methylsulfonylimide [14,15‐EEZE‐mSI]) inhibited EET‐induced cell invasion and migration. 11,12‐EET induced cell stretching and myosin‐actin microfilament formation as well as increased phosphorylation of EGFR and Akt (Ser473), while 14,15‐EEZE inhibited these effects. These results suggest that EET induce and EET antagonists inhibit cell motility, possibly by putative EET receptor‐mediated EGFR and PI3K/Akt pathways, and suggest that EET antagonists are potential therapeutic agents for prostate cancer. (Cancer Sci 2010; 101: 2629–2636)     

Roles of partially purified antigens from Gnathostoma spinigerum larvae on antibody production by human B cell culture

A 24 kDa protein from advanced third stage Gnathostoma spinigerum larvae (GsAL3) is used for gnathostomiasis serodiagnosis. This study investigated whether partially purified protein antigen (Ag) from GsAL3 (Gnath Ag), prepared by simple gel filtration chromatography, could be used for serodiagnosis. Using DNA microarray analysis, significant gene expression related to immunoreactivity was examined in peripheral blood mononuclear cells (PBMC) cocultured with Gnath Ag. Antigenicity was then determined by its capacity to induce antibody production among purified naive B cells stimulated with Gnath Ag and anti-CD40. Seven and 14 days post-exposure, immunoglobulin levels (Igs) in culture supernatants were determined by enzyme-linked immunosorbent assay. The Gnath Ag stimulated PBMC had a significant increase in gene expression related to an innate immune response and decreased cell mediated immunity, but the expression of gene related antibody production was not markedly increased. The Gnath Ag stimulated naive B cells or lipopolysaccharide primed B cells to produce low levels of specific antibody. Our findings support the assertion that partially purified Gnath Ag possess low antigenicity for Ig induction. Further studies are needed to improve G. spinigerum larva Ag for serodiagnosis.     

Cytotoxic pentacyclic and tetracyclic aromatic sesquiterpenes from Phomopsis archeri

Three new sesquiterpenes, named phomoarcherins A-C (1-3), and four known compounds, kampanol A (4), R-mevalonolactone, ergosterol, and ergosterol peroxide, were isolated from the endophytic fungus Phomopsis archeri. These structures were established on the basis of spectroscopic evidence. The structure and absolute configuration of 1 were confirmed by X-ray crystallographic analysis of its p-bromobenzoate derivative (1a). Compounds 1-4 showed cytotoxicity against five cholangiocarcinoma cell lines (0.1-19.6 μg/mL), while 1 and 2 exhibited weak cytotoxicity against the KB cell line with IC(50) values of 42.1 and 9.4 μg/mL, respectively. In addition, compound 2 showed antimalarial activity against Plasmodium falciparum with an IC(50) value of 0.79 μg/mL.     

Protection from myocardial ischemia/reperfusion injury by a positive allosteric modulator of the A₃ adenosine receptor

Adenosine is increased in ischemic tissues where it serves a protective role by activating adenosine receptors (ARs), including the A? AR subtype. We investigated the effect of N-{2-[(3,4-dichlorophenyl)amino]quinolin-4-yl}cyclohexanecarboxamide (LUF6096), a positive allosteric modulator of the A? AR, on infarct size in a barbital-anesthetized dog model of myocardial ischemia/reperfusion injury. Dogs were subjected to 60 min of coronary artery occlusion and 3 h of reperfusion. Infarct size was assessed by macrohistochemical staining. Three experimental groups were included in the study. Groups I and II received two doses of vehicle or LUF6096 (0.5 mg/kg i.v. bolus), one administered before ischemia and the other immediately before reperfusion. Group III received a single dose of LUF6096 (1 mg/kg i.v. bolus) immediately before reperfusion. In preliminary in vitro studies, LUF6096 was found to exert potent enhancing activity (EC?? 114.3 ± 15.9 nM) with the canine A? AR in a guanosine 5'-[γ-[3?S]thio]triphosphate binding assay. LUF6096 increased the maximal efficacy of the partial A? AR agonist 2-chloro-N?-(3-iodobenzyl)adenosine-5'-N-methylcarboxamide and the native agonist adenosine more than 2-fold while producing a slight decrease in potency. In the dog studies, administration of LUF6096 had no effect on any hemodynamic parameter measured. Pretreatment with LUF6096 before coronary occlusion and during reperfusion in group II dogs produced a marked reduction in infarct size (～50% reduction) compared with group I vehicle-treated dogs. An equivalent reduction in infarct size was observed when LUF6096 was administered immediately before reperfusion in group III dogs. This is the first study to demonstrate efficacy of an A? AR allosteric enhancer in an in vivo model of infarction.