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Selected AbstractsEffect of antibody solution conditions on filter performance for virus removal filter PlanovaÔ 20NBIOTECHNOLOGY PROGRESS, Issue 4 2010Tomoko Hongo-Hirasaki Abstract We investigated the effect of antibody solution conditions (ionic strength, pH, IgG concentration, buffer composition, and aggregate level (dimer content)) on filter performance for a virus removal filtration process using the PlanovaÔ 20N, a virus removal filter. Ionic strength and pH affected the filter flux. A consistent high flux was maintained at an ionic strength greater than 10 mM and at pH 4,8 under a typical buffer composition (sodium chloride, citrate, acetate, and phosphate). Optimum IgG concentration was 10,20 mg/mL allowing for high throughput (kg/m2 of IgG). Dimer content negligibly affected the flux level. Under high throughput conditions, virus spiking did not affect flux whereas a parvovirus logarithmic reduction value greater than 5 was maintained. From the results of zeta potential analyses for IgG and the membrane, we considered that electrostatic interactions between antibodies and the membrane affect filter performance (flux level and throughput). These results indicate that the PlanovaÔ 20N filter is applicable for a wide range of solution conditions typically used in antibody processing. © 2010 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [source] Temporal indication of cannabis use by means of THC glucuronide determinationDRUG TESTING AND ANALYSIS, Issue 11-12 2009Ute Mareck Abstract According to the regulations of the World Anti-Doping Agency (WADA), the use of cannabinoids is forbidden in competition. In doping controls, the detection of cannabinoid misuse is based on the analysis of the non-psychoactive metabolite 11-nor-9-carboxy-delta-9-tetrahydrocannabinol (carboxy-THC). The determination of values greater than 15 ng/mL in urine represents an adverse analytical finding; however, no accurate prediction of the time of application is possible as the half-life of carboxy-THC ranges between three and four days. Consequently the detection of carboxy-THC in doping control urine samples collected in competition might also result from cannabis use in out-of-competition periods. The analysis of the glucuronide of the pharmacologically active delta 9-tetrahydrocannabinol (THC-gluc) may represent a complementary indicator for the detection of cannabis misuse in competition. An assay for the determination of THC-gluc in human urine was established. The sample preparation consisted of liquid-liquid extraction of urine specimens, and extracts were analysed by liquid chromatography/tandem mass spectrometry (LC-MS/MS). Authentic doping-control urine samples as well as specimens obtained from a controlled smoking study were analysed and assay characteristics such as specificity, detection limit (0.1 ng/mL), precision (>90%), recovery (,80%), and extraction efficiency (90%) were determined. Copyright © 2010 John Wiley & Sons, Ltd. [source] Effects of sublethal concentrations of atrazine and nitrate on metamorphosis of the African clawed frogENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 3 2003Karen Brown Sullivan Abstract Tadpoles of the African clawed frog (Xenopus laevis) were exposed to sublethal concentrations of atrazine (0, 40, and 320 ,g/L) and nitrate (0, 37, and 292 mg/L) from feeding stage to metamorphosis. A 3 × 3 factorial design was used to identify both single and interactive effects. At metamorphosis, tadpole weight, snout,vent length (SVL), and hematocrit were determined. Mean mortality was greater in tanks receiving 320 ,g/L atrazine; nitrate had no effect on mortality. Significant differences for all mean traits at metamorphosis occurred among atrazine treatments; higher atrazine exposure increased time to metamorphosis and decreased weight, SVL, and hematocrit. Nitrate treatments were not significantly different. Significant interaction tests between atrazine and nitrate occurred for weight and SVL at metamorphosis; the specific type of interaction varied among treatments. Assuming an additive mixture model, at low atrazine (40 ,g/L), the addition of 37 mg/L nitrate produced SVL values less than expected (a synergistic effect) while the addition of 292 mg/L nitrate yielded SVL values greater than expected (an antagonistic effect). A similar response was noted for tadpoles in the 320-,g/L atrazine treatments. These results indicate that environmentally realistic concentrations of atrazine exert a negative impact on amphibian metamorphosis. Also, this study suggests that mixtures of agricultural chemicals, even if sublethal, may exert negative and not necessarily consistent mixture effects. [source] Probing the access of protons to the K pathway in the Paracoccus denitrificans cytochrome c oxidaseFEBS JOURNAL, Issue 2 2005Oliver-M. In recent studies on heme-copper oxidases a particular glutamate residue in subunit II has been suggested to constitute the entry point of the so-called K pathway. In contrast, mutations of this residue (E78II) in the Paracoccus denitrificans cytochrome c oxidase do not affect its catalytic activity at all (E78IIQ) or reduce it to about 50% (E78IIA); in the latter case, the mutation causes no drastic decrease in heme a3 reduction kinetics under anaerobic conditions, when compared to typical K pathway mutants. Moreover, both mutant enzymes retain full proton-pumping competence. While oxidized-minus-reduced Fourier-transform infrared difference spectroscopy demonstrates that E78II is indeed addressed by the redox state of the enzyme, absence of variations in the spectral range characteristic for protonated aspartic and glutamic acids at ,,1760 to 1710 cm,1 excludes the protonation of E78II in the course of the redox reaction in the studied pH range, although shifts of vibrational modes at 1570 and 1400 cm,1 reflect the reorganization of its deprotonated side chain at pH values greater than 4.8. We therefore conclude that protons do not enter the K channel via E78II in the Paracoccus enzyme. [source] A new automated delineation method for SPECT lung scans using adaptive dual-exponential thresholdingINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 1 2007Alex Wang Abstract An accurate method for delineating lung contours in single photon emission computed tomography (SPECT) is critical to respiratory studies such as pulmonary embolism (PE) and respiratory aerosol deposition. Current delineation methods are not adaptive in nature and may require a priori information on lung volumes. We have developed a dual-exponential thresholding method that solely requires SPECT scans, and is fast, accurate, and adaptive in nature. A dataset consisted of 90 patients was studied retrospectively. While most were suspected of PE, other pulmonary disorders were also present. SPECT ventilation scans were obtained after inhalation of ,40 MBq of 99mTc-Technegas. Examination of the corresponding natural logarithmically transformed histograms revealed dual exponential functions like pattern. Adaptive thresholds were found as the intercept between the two exponential functions. 350 Monte Carlo simulations representative of normally-ventilated scans with varying counts were used to quantitatively measure and evaluate the method. Our method correctly delineated lung volumes to above 97% agreement for 310 of the 350 Monte Carlo simulations with maximum count values greater than or equal to 31. The 40 low-count simulations were included purely as extreme cases. For real patient scenario, an experienced physician was called upon to visually delineate a sample of 50 actual patient scans, and these delineated lung volumes were used as gold standard and compared with those delineated using our method. Our results had an average of 96% agreement. © 2007 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 17, 22,27, 2007 [source] Lower urinary tract symptoms and risk of prostate cancer in Japanese menINTERNATIONAL JOURNAL OF UROLOGY, Issue 8 2006AKIO MATSUBARA Aim: Our aim was to investigate whether or not men with lower urinary tract symptoms are at increased risk of prostate cancer. Methods: A total of 3511 men aged 50,79 years who underwent mass screening for prostate cancer between 2002 and 2004 for the first time, and completed the International Prostate Symptom Score (IPSS) questionnaire at the time of the prostate specific antigen (PSA) test, were enrolled in the present study. All men with PSA values greater than 4.0 ng/mL were advised and encouraged to undergo transrectal systematic sextant biopsy. The number of cancers subsequently detected was compared between men with IPSS scores of 0,7 and 8,35. Results: Of the 3511 men, 219 (6.2%) had PSA values greater than 4 ng/mL, 178 (5.1%) underwent biopsy, and 51 (1.5%) were found to have prostate cancer. Although the PSA positivity rate for men with IPSS scores of 8,35 was significantly higher than that in the 0,7 group, there were no significant intergroup differences in the cancer detection rates for biopsied men and for total screened subjects. Multivariate logistic regression analysis revealed that prostate volume was the dominant predictor for the detection of prostate cancer, followed by PSA level, but the IPSS made no significant contribution. No significant difference was noted in the IPSS scores between men with cancer and the others of the same age group. Conclusions: Symptomatic Japanese men are not at higher risk of prostate cancer despite their higher PSA values compared with asymptomatic men of the same age group. [source] Spring Cereals for Forage and Grain Production in a Cool Maritime ClimateJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 1 2003A. G. Todd Abstract Newfoundland's climate is marginal for agricultural production. The availability of locally grown cereal grain and high-quality forage are major limitations to successful animal agriculture in this region. Here, our overall objective was to compare several spring cereal species for both annual forage and grain production in Newfoundland's cool Maritime climate. Several varieties of barley (Hordeum vulgare L.), wheat (Triticum aesitivum L.), oats (Avena sativa L.) and pea (Pisum sativum L.),cereal mixtures for forage yield and quality, as well as grain yield and maturity, were compared in field trials on the east and west coasts in both 1999 and 2000. Barley headed earliest, yielded greatest forage dry matter, had lowest forage protein and acid detergent fibre (ADF) percentages, and had neutral detergent fibre (NDF) mean values greater than those of pea,cereal mixtures, but less than those of oats and wheat. Forage harvested from pea,cereal mixtures was similar to that of barley for yield, ADF and NDF, while P and protein percentage were much greater. Barley matured 10,15 days earlier than both wheat and oats. In general terms, all three spring cereals exhibited similar grain yield potential. Oats tillered less, but compensated by producing more kernels spike,1. Days to maturity for cereal grains in western Newfoundland were roughly similar to those reported for the Maritime provinces of Canada. Yield and maturity results for both forage and grain production suggest that eastern Newfoundland is a unique agro-ecoregion in North America, and agronomic recommendations specific to other regions may not be applicable in this region. [source] Middle cerebral artery peak systolic velocity and ductus venosus velocity in the investigation of nonimmune hydropsJOURNAL OF CLINICAL ULTRASOUND, Issue 7 2009Sedigheh Borna MD Abstract Purpose. This study was performed to investigate the cause of nonimmune hydrops fetalis by measuring the peak systolic velocity (PSV) in the middle cerebral artery (MCA) and velocity waveforms of the ductus venosus (DV) with Doppler. Methods. This cross-sectional study was done on 19 pregnancies referred to three university teaching hospitals for further investigation of nonimmune hydrops fetalis in 2007 and 2008. The MCA-PSV and DV velocity waveforms were recorded in all fetuses. Anemia was investigated in cases with MCA-PSV values greater than 1.50 MoM (multiple of the median). Cardiovascular causes and chromosomal abnormalities were investigated in fetuses with abnormal DV velocity. Results. Four of 19 fetuses had MCA-PSV values greater than 1.50 MoM. The causes of anemia were cytomegalovirus, parvovirus B19 infections, congenital heart disease, and Turner syndrome. Four cases had reversed flow in the DV; three of them had congenital heart disease on echocardiography; and one had a normal echocardiogram, but an abnormal karyotype was detected. Conclusion. Assessment of the MCA-PSV and DV velocity waveforms during sonographic examination of fetuses with nonimmune hydrops fetalis may improve our knowledge about the etiology of this condition. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2009 [source] HYDROCARBON POTENTIAL OF THE LATE CRETACEOUS GONGILA AND FIKA FORMATIONS, BORNU (CHAD) BASIN, NE NIGERIAJOURNAL OF PETROLEUM GEOLOGY, Issue 4 2010B. Alalade The hydrocarbon potential of possible shale source rocks from the Late Cretaceous Gongila and Fika Formations of the Chad Basin of NE Nigeria is evaluated using an integration of organic geochemistry and palynofacies observations. Total organic carbon (TOC) values for about 170 cutting samples range between 0.5% and 1.5% and Rock-Eval hydrogen indices (HI) are below 100 mgHC/gTOC, suggesting that the shales are organically lean and contain Type III/IV kerogen. Amorphous organic matter (AOM) dominates the kerogen assemblage (typically >80%) although its fluorescence does not show a significant correlation with measured HI. Atomic H/C ratios of a subset of the samples indicate higher quality oil- to gas-prone organic matter (Type II-III kerogens) and exhibit a significant correlation with the fluorescence of AOM (r2= 0.86). Rock-Eval Tmax calibrated against AOM fluorescence, biomarker and aromatic hydrocarbon maturity data suggests a transition from immature (<435°C) to mature (>435°C) in the Fika Formation and mature to post-mature (>470°C) in the Gongila Formation. The low TOC values in most of the shales samples limit their overall source rock potential. The immature to early mature upper part of the Fika Formation, in which about 10% of the samples have TOC values greater than 2.0%, has the best oil generating potential. Oil would have been generated if such intervals had become thermally mature. On the basis of the samples studied here, the basin has potential for mostly gaseous rather than liquid hydrocarbons. [source] Quantitative analysis of the major constituents of St John's wort with HPLC-ESI-MSJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 12 2005Dhammitha H. Chandrasekera A method was developed to profile the major constituents of St John's wort extracts using highperformance liquid chromatography-electrospray mass spectrometry (HPLC-ESI-MS). The objective was to simultaneously separate, identify and quantify hyperforin, hypericin, pseudohypericin, rutin, hyperoside, isoquercetrin, quercitrin and chlorogenic acid using HPLC-MS. Quantification was performed using an external standardisation method with reference standards. The method consisted of two protocols: one for the analysis of flavonoids and glycosides and the other for the analysis of the more lipophilic hypericins and hyperforin. Both protocols used a reverse phase Luna phenyl hexyl column. The separation of the flavonoids and glycosides was achieved within 35 min and that of the hypericins and hyperforin within 9 min. The linear response range in ESI-MS was established for each compound and all had linear regression coefficient values greater than 0.97. Both protocols proved to be very specific for the constituents analysed. MS analysis showed no other signals within the analyte peaks. The method was robust and applicable to alcoholic tinctures, tablet/capsule extracts in various solvents and herb extracts. The method was applied to evaluate the phytopharmaceutical quality of St John's wort preparations available in the UK in order to test the method and investigate if they contain at least the main constituents and at what concentrations. [source] pH-responsive ampholytic terpolymers of acrylamide, sodium 3-acrylamido-3-methylbutanoate, and (3-acrylamidopropyl)trimethylammonium chloride.JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 13 2004Abstract The solution properties of low-charge-density ampholytic terpolymers of acrylamide, sodium 3-acrylamido-3-methylbutanoate, and (3-acrylamidopropyl)trimethylammonium chloride were studied as functions of the solution pH, ionic strength, and polymer concentration. Terpolymers with low charge densities, large charge asymmetries, or both exhibited excellent solubility in deionized (DI) water, and higher charge density terpolymers were readily dispersible in DI water; however, the higher charge density terpolymer solutions separated into polymer-rich and polymer-poor phases upon standing over time. Charge-balanced terpolymers exhibited antipolyelectrolyte behavior at pH values greater than or equal to the ambient pH (6.5 ± 0.2); the same terpolymers behaved increasingly as cationic polyelectrolytes with decreasing solution pH because of the protonation of the 3-acrylamido-3-methylbutanoate (AMB) repeat units. Unbalanced terpolymers generally exhibited polyelectrolyte behavior, although the effects of intramolecular electrostatic attractions (i.e., polyampholyte effects) on the hydrodynamic volume of the unbalanced terpolymer coils were evident at certain values of the solution pH and salt concentration. The dilute-solution behavior of the terpolymers correlated well with the behavior predicted by several polyampholyte solution theories. In the semidilute regime, solution viscosities increased with increasing terpolymer charge density, and this indicated a significant enhancement of the solution viscosity by intermolecular electrostatic associations. Upon the addition of NaCl, semidilute-solution viscosities tended to decrease because of the disruption of the intermolecular electrostatic associations. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3252,3270, 2004 [source] Lycopene content differs among red-fleshed watermelon cultivars,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 10 2001Penelope Perkins-Veazie Abstract Lycopene, a carotenoid, has antioxidant properties that may reduce the incidence of certain cancers. Watermelon (Citrullus lanatus (Thunb) Matsum & Nakai) is a natural source of lycopene, with a reported average content of 48.7,µg,g,1 fresh weight based on samples taken from retail produce. This study demonstrated the variability of lycopene content in 11 red-fleshed watermelon cultivars grown at one location, representing seedless, open-pollinated and hybrid types, and in commercially shipped hybrid and seedless melons, representing seasonal production periods. Tristimulus colorimeter a* and chroma values were positively correlated with lycopene values, but linear or quadratic regressions of colorimeter data against lycopene values were not significant. Tristimulus colorimeter readings from cut melons were compared to amounts of lycopene extracted from the same melons. Lycopene content varied widely among cultivars, with four cultivars having mean values greater than 65.0,µg,g,1 fresh weight. Seedless types sampled tended to have higher amounts of lycopene (>50.0,µg,g,1 fresh weight) than seeded types. Watermelon lycopene content changed for some cultivars with production season. Published in 2001 for SCI by John Wiley & Sons, Ltd [source] Antibacterial and Hemolytic Activities of Quaternary Pyridinium Functionalized PolynorbornenesMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 5 2008Tarik Eren Abstract In this study, amphiphilic polyoxanorbornene with different quaternary alkyl pyridinium side chains were synthesized. The biological efficiencies of these polymers, with various alkyl substituents, were determined by bacterial growth inhibition assays and hemolytic activity (HC50) against human red blood cells (RBCs) to provide selectivity of these polymers for bacterial over mammalian cells. A series of polymers with different alkyl substituents (ethyl, butyl, hexyl, octyl, decyl and phenylethyl) and two different molecular weights (3 and 10 kDa) were prepared. The impact of alkyl chain length divided the biological activity into two different cases: those with an alkyl substituent containing four or fewer carbons had a minimum inhibitory concentration (MIC) of 200 µg,·,mL,1 and a HC50 greater than 1,650 µg,·,mL,1, while those with six or more carbons had lower MICs,,,12.5 µg,·,mL,1 and HC50,,,250 µg,·,mL,1. Using MSI-78, the potent Magainin derivative which has an MIC,=,12.0 µg,·,mL,1 and HC50,=,120 µg,·,mL,1, as a comparison, the polymers with alkyl substituents ,C4 (four carbons) were not very potent, but did show selectivity values greater than or equal to MSI-78. In contrast, those with alkyl substituents ,C6 were as potent, or more potent, than MSI-78 and in three specific cases demonstrated selectivity values similar to, or better than, MSI-78. To understand if these polymers were membrane active, polymer induced lipid membrane disruption activities were evaluated by dye leakage experiments. Lipid composition and polymer hydrophobicity were found to be important factors for dye release. [source] Plasma protein profiles in early asthmatic responses to inhalation allergen challengeALLERGY, Issue 1 2009T. Rhim Although mediators, such as lipids, cytokines, and chemokines, are related to the appearance of an IPR, there has been no reliable indicator to predict conditions for the appearance of an IPR. In this study, we adopted a proteomic approach to investigate the pathogenesis at the level of the plasma proteins and to develop plasma markers to predict the appearance of an IPR following an inhalation challenge with Dermatophagoides pteronyssinus (D.p.). Sixteen mild asthmatics were recruited. Plasma was obtained before challenge and when a decline in forced expiratory volume in 1 s (FEV1) values greater than 20% from the phosphate-buffered saline value was achieved during D.p. allergen challenge (positive responders), or at 60 min after the highest concentration of D.p. allergen was inhaled (negative responders). After comparing normalized volumes of the spots in the two groups, differentially expressed spots were identified using intra-gel digestion and mass spectrometric analysis. Before D.p. antigen challenge, four spots of gamma fibrinogen and its isoforms were significantly decreased and two spots of complement C3 fragments were significantly increased in the positive responders compared to the negative responders. After D.p. antigen challenge, complement C3 fragment was persistently higher, while gamma fibrinogen was lower in the positive responders than in the negative responders. A validation study using Western blotting showed that gamma fibrinogen expression in the IPR-positive asthmatics was significantly decreased compared to the average of the IPR-negative asthmatic control group. These results indicate that alterations in the complement cascade and fibrinogen may predispose patients to the appearance of an immediate response to D.p. allergen challenge and may provide plasma markers to predict the appearance of an IPR. [source] Validation of the short forms of the incontinence impact questionnaire (IIQ-7) and the urogenital distress inventory (UDI-6) in a Turkish population,NEUROUROLOGY AND URODYNAMICS, Issue 1 2007Cetin Cam Abstract Aim To validate the Turkish versions of the IIQ-7 and UDI-6 for use in Turkish-speaking populations. Methods After establishing the test-retest reliability and internal consistency in a pilot study, 302 patients were enrolled in the study and general and subscale scores of the questionnaires were calculated. All participants underwent an urodynamic assessment. Results Both instruments showed a high internal consistency (Cronbach's alpha for the IIQ-7 and UDI-6 was 0.87 and 0.74, respectively) and test-retest reliability (Spearman's rho was 0.99 for both of the scales (P,<,0.001). 55.6% of the participants showed urodynamic abnormality and/or leakage. 39.7% had urodynamic stress incontinence (USI) and 15.9% had detrussor overactivity (DOA),±,USI. The mean scores of each IIQ-7 and UDI-6 were significantly higher in the USI, and DOA,±,USI groups compared with normal women. Women with DOA,±,USI scored highest in the IIQ-7 and UDI-6. The irritative subscale scores of the 1st and 2nd items of the UDI-6 were significantly higher in the DOA,±,USI group. The stress subscale scores of 3rd and 4th items of UDI-6 were significantly higher in the USI group. Women with postvoid residual (PVR) urine values greater than 50 ml had significantly higher obstructive subscale scores compared to the ones who had less residual volumes. Conclusions The Turkish translated versions of the IIQ-7 and UDI-6 are reliable, consistent and valid instruments for assessing symptom severity and the impact on QOL in Turkish speaking women with urinary incontinence. Neurourol. Urodynam. © 2006 Wiley-Liss, Inc. [source] A Note on Comparing Exposure Data to a Regulatory Limit in the Presence of Unexposed and a Limit of DetectionBIOMETRICAL JOURNAL, Issue 6 2005Haitao Chu Abstract In some occupational health studies, observations occur in both exposed and unexposed individuals. If the levels of all exposed individuals have been detected, a two-part zero-inflated log-normal model is usually recommended, which assumes that the data has a probability mass at zero for unexposed individuals and a continuous response for values greater than zero for exposed individuals. However, many quantitative exposure measurements are subject to left censoring due to values falling below assay detection limits. A zero-inflated log-normal mixture model is suggested in this situation since unexposed zeros are not distinguishable from those exposed with values below detection limits. In the context of this mixture distribution, the information contributed by values falling below a fixed detection limit is used only to estimate the probability of unexposed. We consider sample size and statistical power calculation when comparing the median of exposed measurements to a regulatory limit. We calculate the required sample size for the data presented in a recent paper comparing the benzene TWA exposure data to a regulatory occupational exposure limit. A simulation study is conducted to investigate the performance of the proposed sample size calculation methods. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Carbohydrate antigen 19-9 change during chemotherapy for advanced pancreatic adenocarcinomaCANCER, Issue 12 2009Michele Reni MD Abstract BACKGROUND: Radiologic assessment of tumor response in pancreatic cancer is complicated by desmoplastic reactions within or around the tumor. The objective of this study was to evaluate the correlation between a decline in carbohydrate antigen 19-9 (CA 19-9) and survival in patients with advanced pancreatic cancer who received upfront chemotherapy. METHODS: CA 19-9 serum basal values were measured in 247 patients with advanced pancreatic cancer who were enrolled in 5 consecutive trials between 1997 and 2007. Survival curves were compared among patients who had a predefined CA 19-9 nadir variation (<50%. Group 1; 50% to 89%, Group 2; or >89%, Group 3). To eliminate guarantee-time bias, survival analysis was repeated using the landmark method. RESULTS: In both univariate and multivariate analysis, the basal CA 19-9 value significantly predicted survival. The median survival was 15.5 months for 34 patients who had normal basal CA 19-9 values, 11.9 months for 108 patients who had basal values between 38 U/mL and 1167 U/mL, and 8 months for 105 patients who had basal values >1167 U/mL. At least 1 CA 19-9 follow-up value was available for 204 patients who had baseline values greater than normal. A significant difference in overall survival was observed in univariate and multivariate analyses between Groups 1 and 2, between Groups 1 and 3, and between Groups 2 and 3. The results were confirmed using the landmark method. CONCLUSIONS: In this study, baseline CA 19-9 was confirmed as an independent prognostic factor for survival, and it may be considered as a stratification factor in trials in patients with advanced pancreatic cancer. Biochemical response may be used as a complementary measure to radiologic response to provide a better assessment of chemotherapy activity and to drive treatment decisions in clinical practice. Cancer 2009. © 2009 American Cancer Society. [source] | ||||||||||||||||||||||