Acute traumatic spinal cord injury, 1993-2000A population-based assessment of methylprednisolone administration and hospitalization

BACKGROUND: Administration of methylprednisolone sodium succinate (MPSS) after acute traumatic spinal cord injury (TSCI) is controversial. This study compared differences in acute care charge, hospital stay, and related variables as a function of MPSS receipt. METHODS: Determinants of MPSS administration were examined after acute TSCI for South Carolina patients during the period 1993 to 2000 in a multivariate logistic regression model. RESULTS: Administration of MPSS was documented for 48.7% of 1,227 randomly selected patients with TSCI. Patients admitted via trauma centers and emergency departments were more likely to receive MPSS (trama center level 1 odds ratio [OR], 4.06; 95% CI confidence interval [CI], 2.11-7.83; emergency department OR, 1.64; 95% CI, 1.20-2.23). Hospital charge and length of stay were significantly higher for MPSS recipients. CONCLUSIONS: The study findings indicate MPSS use is associated with higher acute care charges and longer hospital stays. These findings suggest the need for outcome studies to assess the long-term benefits of MPSS administration.     

Assessment of flat panel LCD primary class display performance based on AAPM TG 18 acceptance protocol

The image display is an important component of the Picture Archiving and Communication System (PACS) and of digital imaging in general. In this paper, we assess the display performance of 32 different flat panel LCD devices, in terms of their reflection, luminance response, luminance uniformity, resolution, noise, veiling glare and color uniformity included in the tentative guidelines of the AAPM TG18 document version 8.1. We also report on the angular dependencies of luminance and contrast, which constitute one of the miscellaneous tests. The tools used included a telescopic photometer, which was also used as a colorimeter, an illuminance meter, light sources for the reflection assessment, light-blocking devices, and digital TG18 test patterns. The luminance ratio (LR), maximum luminance difference (ALmax) and deviation of contrast response with respect to that of DICOM GSDF were 379.2+/-61.0, 1.6+/-1.1%, and 4.84+/-0.58%, respectively. The maximum luminance nonuniformity was 9.2+/-3.9% for the 10% luminance of the TG18-UNL10 test pattern. In the luminance-based resolution test, the percent luminance difference (deltaL) at the center was 0.78+/-0.42%. In all cases of noise testing, the rectangular target in each square in the three quadrants was visible, as were all 15 targets, except for the smallest one, in each corner pattern and the center pattern. The glare ratio (GR) was 2350+/-1460. The average color uniformity parameter, delta(u',v'), across the display area of each display device was 0.002+/-0.001. Nevertheless, not all of the color uniformity parameters of the display devices associated with a workstation met the acceptance criteria. For 7 selected flat panel displays, the mean specular and diffuse reflection coefficients were 0.0061+/-0.0010 and 0.0017+/-0.0005 cd/m2 per lux, respectively. All of the test results conformed to the criteria recommended by AAPM TG18, indicating that the displays were fully acceptable for diagnostic image interpretation. The maximum viewing angle conforming to the DICOM 3.14 standard luminance responses with a 10% tolerance was found to be approximately 50 degrees in both directions along the vertical axis, 10 degrees in the upper direction and 20 degrees in the lower direction along the horizontal axis, and 20 degrees in the upper direction and 10 degrees in the lower direction along the diagonal axis. Therefore, a radiologist should interpret a displayed image by considering the physical characteristics of the narrow viewing angle of the AMLCD displays. The acceptance testing protocol described herein demonstrates the successful clinical implementation of the guidelines for the viewing conditions of medical displays, and if implemented with a QC program, can be used to determine when LCD devices used for diagnostic interpretation need to be upgraded.     

Evaluation of groEL gene analysis for identification of Borrelia burgdorferi sensu lato

The nucleotide sequences of the groEL genes, the flagellin genes, and the 16S rRNA genes from 22 reference strains of Borrelia were compared. groEL sequence analysis is useful not only in interspecies differentiation but also in intraspecies differentiation of Borrelia afzelii and Borrelia garinii isolates.     

Selective effects of quercetin on the cell growth and antioxidant defense system in normal versus transformed mouse hepatic cell lines

Quercetin is a dietary anticancer chemical that is capable of inducing apoptosis in tumor cells. However, little is known about its biological effect on nonmalignant cells, although the effect is one of the critical criteria to evaluate the clinical efficacy of the anticancer agent. In this study, we investigated the effects of quercetin on cell growth and apoptosis using embryonic normal hepatic cell line (BNL CL.2) and its SV40-transformed cell line (BNL SV A.8). We also evaluated the effects of quercetin on the antioxidant defense system in those cells. BNL SV A.8 cells were more sensitive to quercetin-mediated cytotoxicity than BNL CL.2 cells. In addition, the enzyme assays showed that quercetin actively stimulated the antioxidant defense systems including superoxide dismutase, catalase, glutathione, and glutathione reductase only in the BNL CL.2 cells. In particular, quercetin significantly reduced superoxide dismutase activity and increased the malonaldehyde content in BNL SV A.8 cells. These are thought to be closely related to quercetin-mediated apoptosis. Our findings suggest that quercetin is a dietary flavonoid that is capable of inducing selective growth inhibition and apoptosis in hepatic tumor cells, but not in normal cells.     

Estrogen enhances angiogenesis through a pathway involving platelet-activating factor-mediated nuclear factor-kappaB activation

In this study, we investigated the molecular events involved in estrogen-induced angiogenesis. Treatment of the human endometrial adenocarcinoma cells, HEC-1A, with estrogen up-regulated mRNA expression and protein synthesis of various angiogenic factors such as tumor necrosis factor-alpha, interleukin-1, basic fibroblast growth factor, and vascular endothelial growth factor. The estrogen-dependent induction of the expression was blocked by the platelet-activating factor (PAF) antagonists, WEB 2170. Estrogen treatment caused the activation of nuclear factor (NF)-kappaB in HEC-1A cells and was also blocked by PAF antagonist. Inhibitors of NF-kappaB activation inhibited estrogen-induced mRNA expression and protein synthesis of the angiogenic factors. Estrogen led to a pronounced angiogenesis as assessed by a mouse Matrigel model in vivo and endothelial cell sprouting in vitro. PAF antagonists or NF-kappaB inhibitors significantly inhibited this estrogen-dependent angiogenesis. Estrogen caused phospholipase A2 (PLA2) gene and protein expression. Estrogen-induced vascular endothelial growth factor mRNA expression and sprouting were significantly inhibited by PLA2 inhibitors, suggesting PLA2 expression is the upstream pathway in the estrogen-induced angiogenesis. Taken together, these results suggest that estrogen induces the production of angiogenic factors via a mechanism involving PAF-mediated NF-kappaB activation.     

Alkylphosphocholines: a new therapeutic option in glaucoma filtration surgery

PURPOSE: To investigate the effect of alkylphosphocholines (APCs) on human Tenon fibroblast (HTF) proliferation, migration, and cell-mediated collagen gel contraction. METHODS: HTFs were isolated from tissue samples of three patients obtained during surgery and cultured in DMEM and 10% fetal calf serum (FCS). HTFs (passage 3-6) were treated with one APC in different concentrations spanning the 50% inhibitory concentration (IC(50)), as determined previously. Inhibition of cell proliferation was assessed by the tetrazolium dye reduction assay. Migration was determined in chemoattractant chambers with fibronectin-coated polycarbonated membranes. For inhibition of contraction, three-dimensional collagen gels were seeded with HTFs, and the gel size was measured. Cell viability was determined by the trypan blue exclusion assay. For analysis of the mechanism of action, protein kinase C (PKC) activity was measured. RESULTS: The IC(50) varied between 7.0 and 10.5 microM for all APCs tested. At this concentration, all four APCs inhibited HTF migration and cell-mediated collagen gel contraction in the presence of serum. The inhibitory effects on HTF proliferation, migration, and contraction were observed at nontoxic concentrations. PKC activity was reduced to 50% of control level at the IC(50) of all APCs applied. CONCLUSIONS: APCs are effective inhibitors of HTF proliferation, migration, and cell-mediated contraction of collagen gels at nontoxic concentrations. Their mechanism of action seems to involve the inhibition of the PKC pathway.     

Natural inhibitors of carcinogenesis

Previous collaborative work by our group has led to the discovery of several plant isolates and derivatives with activities in in vivo models of cancer chemoprevention, including deguelin, resveratrol, bruceantin, brassinin, 4'-bromoflavone, and oxomate. Using a panel of in vitro bioassays to monitor chromatographic fractionation, a diverse group of plant secondary metabolites has been identified as potential cancer chemopreventive agents from mainly edible plants. Nearly 50 new compounds have been isolated as bioactive principles in one or more in vitro bioassays in work performed over the last five years. Included among these new active compounds are alkaloids, flavonoids, stilbenoids, and withanolides, as well as a novel stilbenolignan and the first representatives of the norwithanolides, which have a 27-carbon atom skeleton. In addition, over 100 active compounds of previously known structure have been obtained. Based on this large pool of potential cancer chemopreventive compounds, structure-activity relationships are discussed in terms of the quinone reductase induction ability of flavonoids and withanolides and the cyclooxygenase-1 and -2 inhibitory activities of flavanones, flavones and stilbenoids. Several of the bioactive compounds were found to be active when evaluated in a mouse mammary organ culture assay, when used as a secondary discriminator in our work. The compounds (2 S)-abyssinone II, (2 S)-2',4'-dihydroxy-2"-(1-hydroxy-1-methylethyl)dihydrofuro[2,3- h]-flavanone, 3'-[gamma-hydroxymethyl-( E)-gamma-methylallyl]-2,4,2',4'-tetrahydroxychalcone 11'- O-coumarate, isolicoflavonol, isoliquiritigenin, and ixocarpalactone A are regarded as promising leads as potential cancer chemopreventive agents.     

New Polyacetylenes, DGAT inhibitors from the roots of Panax ginseng

The petroleum ether extract of Panax ginseng showed a significant inhibition of the diacylglycerol acyltransferase (DGAT) enzyme from rat liver microsomes. Bioactivity-guided fractionation led to the isolation of two new polyacetylenic compounds, (9 R,10 S)-epoxyheptadecan-4,6-diyn-3-one ( 1) and 1-methoxy-(9 R,10 S)-epoxyheptadecan-4,6-diyn-3-one ( 2). Their chemical structures were elucidated on the basis of spectroscopic evidence and asymmetric synthesis. IC50 values of 9 microg/mL ( 1) and 32 microg/mL ( 2) were obtained.     

Comparison of effects of As2O3 and As4O6 on cell growth inhibition and gene expression profiles by cDNA microarray analysis in SiHa cells

An arsenical compound, As2O3 has been reported to be effective for treating acute leukemia and induce apoptosis in many different tumor cell types. In this study we designed a novel arsenical compound, As4O6, and compared its ability to induce cell growth inhibition as well as gene expression profiles along with As2O3 in HPV16 infected SiHa cervical cancer cells. Both As2O3 and As4O6 induced apoptosis in SiHa cells, as determined by a DNA ladder formation. As4O6 was more effective in suppressing the growth of SiHa cells in vitro, as compared to As2O3. To further compare gene expression profiles between these two drugs, we used a 384 cDNA microarray system. The gene expression profiles were also classified into the Gene Ontology (GO) to investigate apoptosis-related cellular processes. In the case of As2O3, 41 genes were up- or down-regulated at least 2-fold, as compared to non-treatment, whereas, 65 genes were up- or down-regulated by As4O6 treatment. In particular, 27 genes were commonly regulated by both arsenic compounds. The GO analysis also indicated that down-regulation of cell-regulatory functions, such as cell cycle, protein kinase activity and DNA repair, induces an anti-tumor effect. Taken together, these data support that As4O6 could be more effective than As2O3 in inhibiting the growth of HPV16 infected cervical cancer cells. This appears to be mediated through a unique but overlapping regulatory mechanism(s), suggesting that the regulated genes and cellular processes could be used for a new potential drug approach for treating cervical cancer in clinical settings.     

Presence of human mycoplasma DNA in gastric tissue samples from Korean chronic gastritis patients

We aimed to determine whether mycoplasmas are present in Korean chronic gastritis, and to understand their roles in gastric cancer tumorigenesis, because mycoplasmas resemble Helicobacter pylori in terms of ammonia production and induction of inflammatory cytokines in immune and non-immune cells. The presence and identity of mycoplasmas were assessed by semi-nested PCR and sequencing, and the results were compared with pathologic data. Fifty-six samples collected from Korean chronic gastritis patients were used for this study. Twenty-three (41.1%) were positive for mycoplasmas. Eighteen sequenced samples contained a single human mycoplasma or two mycoplasmas, which were identified as Mycoplasma faucium (13/18), M. fermentans (3/18), M. orale (1/18), M. salivarium (2/18), and M. spermatophilum (1/18). Mycoplasma-infected chronic gastritis samples showed significantly more severe neutrophil infiltration than non-infected samples (P=0.0135). Mycoplasma profiles in the oral cavity (M. salivarium is major) and stomach were different, and the presence of significant proinflammatory responses in mycoplasmapositive patients suggests that the mycoplasmas are not simply contaminants. Further studies are required to understand whether mycoplasmas play a role in gastric tumorigenesis.