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Similar Sensitivity (similar + sensitivity)
Selected AbstractsDistribution and functional characterization of human Nav1.3 splice variantsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2005R. Thimmapaya Abstract The focus of the present study is the molecular and functional characterization of four splice variants of the human Nav1.3 , subunit. These subtypes arise due to the use of alternative splice donor sites of exon 12, which encodes a region of the , subunit that resides in the intracellular loop between domains I and II. This region contains several important phosphorylation sites that modulate Na+ channel kinetics in related sodium channels, i.e. Nav1.2. While three of the four Nav1.3 isoforms, 12v1, 12v3 and 12v4 have been previously identified in human, 12v2 has only been reported in rat. Herein, we evaluate the distribution of these splice variants in human tissues and the functional characterization of each of these subtypes. We demonstrate by reverse transcriptase-polymerase chain reaction (RT-PCR) that each subtype is expressed in the spinal cord, thalamus, amygdala, cerebellum, adult and fetal whole brain and heart. To investigate the functional properties of these different splice variants, each , subunit isoform was cloned by RT-PCR from human fetal brain and expressed in Xenopus oocytes. Each isoform exhibited functional voltage-dependent Na+ channels with similar sensitivities to tetrodotoxin (TTX) and comparable current amplitudes. Subtle shifts in the V1/2 of activation and inactivation (2,3 mV) were observed among the four isoforms, although the functional significance of these differences remains unclear. This study has demonstrated that all four human splice variants of the Nav1.3 channel , subunit are widely expressed and generate functional TTX-sensitive Na+ channels that likely modulate cellular excitability. [source] Multiple P2 Receptors Contribute to a Transient Increase in Intracellular Ca2+ Concentration in Atp-Stimulated Rat Brown AdipocytesEXPERIMENTAL PHYSIOLOGY, Issue 6 2002Mariko Omatsu-Kanbe Extracellular ATP in micromolar concentrations evokes a transient elevation in intracellular free Ca2+ concentration ([Ca2+]i), which arises primarily from a release of Ca2+ from intracellular stores in rat brown adipocytes. We investigated the mechanisms underlying this transient nature of [Ca2+]i elevation during exposure to ATP by using fura-2 fluorescence measurements together with the P2 receptor antagonists pyridoxal-phosphate-6-azophenyl-2,,4,-disulfonic acid (PPADS) and suramin. Extracellular ATP (10 ,M) almost completely depressed the thapsigargin (100 nM)-evoked [Ca2+]i elevation mediated through store-operated Ca2+ entry. The inhibitory effect of ATP was antagonized by PPADS with IC50 of 0.7 ,M. In the presence of PPADS at concentrations of more than 5 ,M, the ATP-induced [Ca2+]i elevation became sustained during the entire duration of the agonist application, although the magnitude of the sustained [Ca2+]i elevation was reduced in a concentration-dependent manner by PPADS with an IC50 of 200 ,M. In contrast, the ATP-induced [Ca2+]i elevation was blocked by suramin in a concentration range similar to that required to antagonize the inhibitory effect of ATP on the store-operated pathway. These results suggest that the [Ca2+]i responses to extracellular ATP in rat brown adipocytes are mediated through the activation of at least two distinct P2 receptors exhibiting different sensitivities to PPADS but similar sensitivities to suramin. Extracellular ATP stimulates the PPADS-resistant P2 receptor to mobilize intracellular Ca2+ stores, which is probably followed by the activation of store-operated Ca2+ entry. Extracellular ATP, however, would inhibit this Ca2+ entry process through the stimulation of the PPADS-sensitive P2-receptor, which may underlie the transient nature of [Ca2+]i elevation in response to extracellular ATP. [source] The canopy conductance of a boreal aspen forest, Prince Albert National Park, CanadaHYDROLOGICAL PROCESSES, Issue 9 2004P. D. Blanken Abstract Annual fluxes of canopy-level heat, water vapour and carbon dioxide were measured using eddy covariance both above the aspen overstory (Populus tremuloides Michx.) and hazelnut understory (Corylus cornuta Marsh.) of a boreal aspen forest (53·629 °N 106·200 °W). Partitioning of the fluxes between overstory and understory components allowed the calculation of canopy conductance to water vapour for both species. On a seasonal basis, the canopy conductance of the aspen accounted for 70% of the surface conductance, with the latter a strong function of the forest's leaf area index. On a half-hour basis, the canopy conductance of both species decreased non-linearly as the leaf-surface saturation deficits increased, and was best parameterized and showed similar sensitivities to a modified form of the Ball,Berry,Woodrow index, where relative humidity was replaced with the reciprocal of the saturation deficit. The negative feedback between the forest evaporation and the saturation deficit in the convective boundary layer varied from weak when the forest was at full leaf to strong when the forest was developing or loosing leaves. The coupling between the air at the leaf surface and the convective boundary layer also varied seasonally, with coupling decreasing with increasing leaf area. Compared with coniferous boreal forests, the seasonal changes in leaf area had a unique impact on vegetation,atmosphere interactions. Copyright © 2004 John Wiley & Sons, Ltd. [source] A generalized exo -anomeric effect.ISRAEL JOURNAL OF CHEMISTRY, Issue 3-4 2000Substituent, solvent effects on the conformational equilibria of 2-(arylseleno)cyclohexanones The effects of substitution and solvent on the conformational equilibria of 2-[(4-R-substituted-phenyl)seleno]cyclohexanones are described. The conformational equilibria were determined by comparison of the linewidths of the H-2 resonances in the 1H NMR spectra of the conformationally averaged systems with those of the anancomeric (highly biased) 4-isopropyl-2-substituted cyclohexanones. The substituent (R = NMe2, OMe, Me, H, F, Cl, CF3, NO2) and solvent ((CD3)2CO, CD3CN, CD2Cl2, CDCl3) effects are discussed in terms of electrostatic effects and the possible stabilizing orbital interactions. The values of Keq (axial-equatorial) increase as the substituent becomes more electron withdrawing, in agreement with the dominance of nSe , ,*C=O or ,C-Se , ,*C=O orbital interactions in the axial conformers. The increase in the proportion of the equatorial isomers in more polar solvents for a given substituent suggests a damping of the dipolar interactions in the equatorial isomers. However, the proportion of the equatorial isomers in a given solvent increases as the substituent becomes more electron withdrawing, indicating that electrostatic interactions do not dominate in controlling the conformational equilibria. Analysis of the equilibrium data by means of a dual substituent parameter approach indicates the best correlation with ,I and ,+R substituent constants in CD2Cl2 and with ,I and ,°R substituent constants in CD3CN, with similar sensitivities to the resonance and polar effects. The correlations are interpreted in terms of accommodation of effective positive charge on the selenium atom in the axial isomers in CD2Cl2, and a lesser sensitivity to the buildup of positive charge in the more polar solvent CD3CN. Comparison of the IR ,CO -stretching frequencies for the axial and equatorial ArSe-substituted anancomeric systems (R = NO2, NMe2) indicates a higher stretching frequency for the NO2 -substituted isomers. In the case of the NMe2 -substituted compounds, ,CO appears at a higher frequency in the equatorial isomer, whereas in the case of the NO2 -substituted compounds, ,CO is less sensitive to the axial or equatorial orientation of the substituent. The results are consistent with the operation of nse , ,*c=0 or ,C-Se , ,*C=O orbital interactions in the axial isomers. The JC2-H2 values in the axially-substituted anancomeric isomers are of greater magnitude than those in the equatorially-substituted isomers, which is also consistent with the operation of the orbital interactions described above. There is, however, no marked substituent effect on the JC2,H2 values within the series of axial or equatorial isomers. We argue that this does not support the dominance of ,C-Se , ,*C=O orbital interactions. Examination of crystal structures reported in the literature for related compounds indicates a particular gauche orientation about the C2,Se bond, which lends further support to the operation of an nSe , ,*C=O orbital interaction. We suggest that the latter interaction is a manifestation of a generalized exo -anomeric effect. [source] Diagnosis of breast cancer using diffuse reflectance spectroscopy: Comparison of a Monte Carlo versus partial least squares analysis based feature extraction techniqueLASERS IN SURGERY AND MEDICINE, Issue 7 2006Changfang Zhu MS Abstract Background and Objective We explored the use of diffuse reflectance spectroscopy in the ultraviolet-visible (UV-VIS) spectrum for the diagnosis of breast cancer. A physical model (Monte Carlo inverse model) and an empirical model (partial least squares analysis) based approach, were compared for extracting diagnostic features from the diffuse reflectance spectra. Study Design/Methods The physical model and the empirical model were employed to extract features from diffuse reflectance spectra measured from freshly excised breast tissues. A subset of extracted features obtained using each method showed statistically significant differences between malignant and non-malignant breast tissues. These features were separately input to a support vector machine (SVM) algorithm to classify each tissue sample as malignant or non-malignant. Results and Conclusions The features extracted from the Monte Carlo based analysis were hemoglobin saturation, total hemoglobin concentration, beta-carotene concentration and the mean (wavelength averaged) reduced scattering coefficient. Beta-carotene concentration was positively correlated and the mean reduced scattering coefficient was negatively correlated with percent adipose tissue content in normal breast tissues. In addition, there was a statistically significant decrease in the beta-carotene concentration and hemoglobin saturation, and a statistically significant increase in the mean reduced scattering coefficient in malignant tissues compared to non-malignant tissues. The features extracted from the partial least squares analysis were a set of principal components. A subset of principal components showed that the diffuse reflectance spectra of malignant breast tissues displayed an increased intensity over wavelength range of 440,510 nm and a decreased intensity over wavelength range of 510,600 nm, relative to that of non-malignant breast tissues. The diagnostic performance of the classification algorithms based on both feature extraction techniques yielded similar sensitivities and specificities of approximately 80% for discriminating between malignant and non-malignant breast tissues. While both methods yielded similar classification accuracies, the model based approach provided insight into the physiological and structural features that discriminate between malignant and non-malignant breast tissues. Lasers Surg. Med. © 2006 Wiley-Liss, Inc. [source] Modelling sources and sinks of CO2, H2O and heat within a Siberian pine forest using three inverse methodsTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 590 2003M. Siqueira Abstract Source/sink distributions of heat, CO2 and water vapour in a Siberian Scots pine forest were estimated from measured concentration and temperature profiles using three inverse analysis methods. These methods include: a Eulerian second-order closure model (EUL); a localized near-field Lagrangian dispersion model (LNF); and a hybrid model (HEL) which uses the Eulerian second-order turbulence model to calculate the flow statistics combined with the regression analysis used with the Lagrangian model. Model predictions were compared to heat flux profiles measured at five levels in the canopy, and to CO2 and water-vapour fluxes measured close to the ground and above the forest. Predictions of sensible-heat flux profiles by the LNF and HEL schemes were systematically better than results from the EUL analysis. This improvement was attributed to the redundancy in the measured profile (scalar concentration and temperature) data for LNF and HEL and to the imposed smoothness condition used in the regression analyses, whereas the EUL approach calculates a source for each level without any redundancy. The LNF and HEL schemes were also better than EUL in predicting source distributions for CO2 and water vapour, although errors were larger than for sensible heat. The main novelty in our study is the use of EUL to decompose the vertical variability in scalar (or heat) sources into variability produced by the inhomogeneity in flow statistics and variability inferred from the measured mean scalar concentration (or temperature) profile. Hence, it is possible with this analysis to assess how much ,new information' about the source variability is attributed to vertical variation in the measured mean scalar concentration (or temperature) profiles. The analysis shows that measured water vapour concentration profiles provide little information on the inferred source distribution, whereas the CO2 profiles contain more information. Monte Carlo simulations show that computed sources from all three inverse methods have similar sensitivities to errors in measured temperatures. Errors are reduced when the reference temperature above the canopy is held fixed, implying that errors in this temperature propagate throughout the entire domain. When information content and error estimations are combined, a valuable tool to assess the quality of source prediction by inverse methods can be generated. Copyright © 2003 Royal Meteorological Society [source] The lethal effects of gamma irradiation on larvae of the Huhu beetle, Prionoplus reticularis: a potential quarantine treatment for New Zealand export pine treesENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2000Philip J. Lester Abstract Gamma irradiation was investigated as a possible method for disinfestation of huhu beetle larvae, Prionoplus reticularis White, in Pinus radiata D. Don. Larvae of four representative size classes were irradiated at six doses, and the lethal dose (LD99) calculated from mortality data 3 days and 10 days post treatment. All larval size classes showed a similar sensitivity to gamma irradiation and required 3677 Gray (Gy) and 2476 Gy for a LD99 3 and 10 days post-treatment, respectively. The penetration of gamma irradiation into pine wood was found to be lowest in freshly cut logs, and decreased linearly at a rate of 0.698 Gy mm,1 of wood. The penetration was greatest in wood that had been stored for 2 years, and decreased 0.512 Gy mm,1 of wood. These results are likely to be correlated with wood moisture content. Gamma irradiation appears to be a potential alternative method to fumigation for quarantine treatment of P. reticularis. [source] Relative sensitivity of bull trout (Salvelinus confluentus) and rainbow trout (Oncorhynchus mykiss) to acute copper toxicityENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 3 2002James A. Hansen Abstract Bull trout (Salvelinus confluentus) were recently listed as threatened in the United States under the federal Endangered Species Act. Past and present habitat for this species includes waterways contaminated with heavy metals released from mining activities. Because the sensitivity of this species to copper was previously unknown, we conducted acute copper toxicity tests with bull and rainbow trout (Oncorhynchus mykiss) in side-by-side comparison tests. Bioassays were conducted using water at two temperatures (8°C and 16°C) and two hardness levels (100 and 220 mg/L as CaCO3). At a water hardness of 100 mg/L, both species were less sensitive to copper when tested at 16°C compared to 8°C. The two species had similar sensitivity to copper in 100-mg/L hardness water, but bull trout were 2.5 to 4 times less sensitive than rainbow trout in 220-mg/L hardness water. However, when our results were viewed in the context of the broader literature on rainbow trout sensitivity to copper, the sensitivities of the two species appeared similar. This suggests that adoption of toxicity thresholds that are protective of rainbow trout would be protective of bull trout; however, an additional safety factor may be warranted because of the additional level of protection necessary for this federally threatened species. [source] Qualitative and quantitative evaluation of equine respiratory mechanics by impulse oscillometryEQUINE VETERINARY JOURNAL, Issue 1 2006E. VAN ERCK Summary Reasons for performing study: The long- established conventional reference technique (CRT) for measuring respiratory mechanics in horses lacks sensitivity and there is a need for further refinement in new technology, such as the impulse oscillometry system (IOS). Objectives: To evaluate the potential use of the IOS as a clinical respiratory function test and compare it to the current CRT in horses suffering from common upper and lower airway dysfunctions. Methods: Six healthy horses were tested before and after induction of a unilateral nasal obstruction (UNO) or transient left laryngeal hemiplegia (LLH). Six heaves-affected horses were tested in clinical remission and during a heaves crisis, before and after nebulisation of cumulative doses of a bronchodilator therapy (ipratropium bromide; IPB). Results: As opposed to the CRT, the IOS was able to detect partial upper airway obstruction (UAO) caused by UNO or LLH in resting horses, without differentiating both conditions. Upper airway obstruction caused an upward shift of resistance (Rrs) from 5 to 35 Hz without altering reactance (Xrs). As for the CRT, IOS respiratory parameters measured in heaves-affected horses in crisis differed significantly from values measured during remission. The difference in frequency-dependent behaviour of Rrs and Xrs allowed discrimination between upper and lower airway obstructions. Bronchodilator treatment induced significant dose-dependent changes in Xrs at 5 and 10 Hz, from the first dose. Total pulmonary resistance (RL) and Rrs at 5 Hz were affected from the second dose and displayed similar sensitivity. Although post treatment RL values were comparable to remission, Rrs and Xrs remained significantly different, characterising persistent peripheral obstruction. Conclusions: The IOS was more sensitive than the CRT in detecting partial UAO in resting horses and persistent post treatment peripheral dysfunction in heaves-affected horses. The IOS is a sensitive test that provides graded quantitative and qualitative information on disease-induced respiratory dysfunctions as well as on treatment efficiency in horses. Potential relevance: The IOS could represent a practical and sensitive alternative respiratory function test for routine clinical investigations of common airway obstructive diseases and therapy in horses. [source] A Closed Form Slug Test Theory for High Permeability AquifersGROUND WATER, Issue 1 2005David W. Ostendorf We incorporate a linear estimate of casing friction into the analytical slug test theory of Springer and Gelhar (1991) for high permeability aquifers. The modified theory elucidates the influence of inertia and casing friction on consistent, closed form equations for the free surface, pressure, and velocity fluctuations for overdamped and under-damped conditions. A consistent, but small, correction for kinetic energy is included as well. A characteristic velocity linearizes the turbulent casing shear stress so that an analytical solution for attenuated, phase shifted pressure fluctuations fits a single parameter (damping frequency) to transducer data from any depth in the casing. Underdamped slug tests of 0.3, 0.6, and 1 m amplitudes at five transducer depths in a 5.1 cm diameter PVC well 21 m deep in the Plymouth-Carver Aquifer yield a consistent hydraulic conductivity of 1.5 × 10,3 m/s. The Springer and Gelhar (1991) model underestimates the hydraulic conductivity for these tests by as muchas 25% by improperly ascribing smooth turbulent casing friction to the aquifer. The match point normalization of Butler (1998) agrees with our fitted hydraulic conductivity, however, when friction is included in the damping frequency. Zurbuchen et al. (2002) use a numerical model to establish a similar sensitivity of hydraulic conductivity to nonlinear casing friction. [source] Dark lumen magnetic resonance enteroclysis in combination with mri colonography for whole bowel assessment in patients with Crohn's disease: First clinical experienceINFLAMMATORY BOWEL DISEASES, Issue 4 2005Andreas G Schreyer MD Abstract Background: Magnetic resonance enteroclysis (MRE) is a recently introduced imaging technique that assesses the small bowel with similar sensitivity and specificity as the fluoroscopically performed conventional enteroclysis. Magnetic resonance imaging colonography (MRC) seems to be a promising technique for polyp assessment in the colon. In this feasibility study, we evaluated the combination of small bowel MRI with unprepared MRC as an integrative diagnostic approach of the whole bowel in patients with Crohn's disease. Methods: Thirty patients with known Crohn's disease were prospectively examined. No particular colonic preparation was applied. Applying the dark lumen technique in all patients, MRE and MRC were performed within 1 session using an integrative examination protocol. T2-weighted and contrast-enhanced T1-weighted sequences were acquired. Inflammation assessment (grades 0 to 2) of the colon was compared with conventional colonoscopy in 29 patient and with surgery in 1 patient. The entire colon was graded fair to good distended in all patients. In 11 of 210 evaluated colonic segments, feces hindered an adequate intraluminal bowel assessment. Twenty-three of 30 patients had complete colonoscopy as the gold standard. In 7 patients, complete colonoscopy could not be performed because of an inflamed stenosis. Results: Correct grading of colonic inflammation was performed with 55.1% sensitivity and 98.2% specificity in all segments. Considering only more extensive inflammation (grade 2), the sensitivity of MRC increased to 70.2% with a specificity of 99.2%. Conclusions: The combination of MRE and MRC could improve the diagnostic value of abdominal MRI evaluation in patients with Crohn's disease. However, MRC can not replace conventional colonoscopy in subtle inflammation assessment. [source] Rapid detection of metastasis of gastric cancer using reverse transcription loop-mediated isothermal amplificationINTERNATIONAL JOURNAL OF CANCER, Issue 5 2007Daisuke Horibe Abstract Tailor-made surgeries for patients with solid malignancies have been under consideration on the basis of the development of new approaches for minor metastatic foci of malignant tumors. Accurate and reliable methods to detect metastases in biopsy specimens with certain rapidity are essential for the performance of these surgeries. The aim of this study was to develop a rapid and practical method to detect metastasis in specimens from patients with gastric carcinoma with the use of reverse transcription loop-mediated isothermal amplification (RT-LAMP) reaction, a novel technique for detecting mRNA expressions of targeted sequences with high sensitivity, specificity and rapidity under isothermal conditions. RT-LAMP primers to detect cytokeratin19 (CK19) mRNA were generated and 92 lymph nodes (LNs) obtained from 9 patients with gastric cancer were tested for tumor metastases with this technique. Among 92 LNs, 15 were metastasis-positive by routine histopathological examination. RT-LAMP reaction detected CK19 expression in all of the pathologically positive LNs and in 16 of 77 negative LNs. Nested RT-PCR assay for CK19 expression was also performed on 2 of the 9 cases including 32 LNs. The agreement rate of CK19 expression detection by RT-LAMP and RT-PCR analysis was 31/32 (97%). The RT-LAMP technique showed similar sensitivity to detect metastases as nested RT-PCR assay, with a rapidity comparable to that of intraoperative histopathological examination with frozen sectioning and hematoxylin and eosin staining. This method is expected to play an essential role in the performance of tailor-made surgeries in the near future. © 2006 Wiley-Liss, Inc. [source] From gene profiling to diagnostic markers: IL-18 and FGF-2 complement CA125 as serum-based markers in epithelial ovarian cancerINTERNATIONAL JOURNAL OF CANCER, Issue 7 2006Cécile Le Page Abstract We used an oligonucleotide-based DNA microarray to identify potential markers in 39 primary cultures of ovarian cancer specimens compared with 11 primary cultures of normal ovarian epithelia. Differential gene expression of IL-18 and FGF-2 was validated on a subset of samples by quantitative PCR and by IHC, using an independent tissue array of 90 cores of 20 normal ovarian surface epithelia and 70 EOCs representing different grades and pathologies of ovarian disease. We further compared, by ELISA, these two markers with CA125 in sera from 25 cancer-free and 47 ovarian cancer patients. IL-18 and FGF-2 proteins were significantly elevated in tumor tissues (p<0.04) and sera (p<0.05) from patients with ovarian cancer. In combination, the three markers (IL-18, FGF-2, and CA125) showed similar sensitivity in scoring for ovarian cancer (35/45 patients) compared to that of CA125 alone (37/45) and significantly improved the specificity of detection (20/25 patients) compared to each marker individually (15/25 for CA125; 18/25 FGF-2; 16/25 for IL-18). In conclusion we show that a combination of the three serum markers (IL-18, FGF-2 and CA125) is associated with EOC, with higher specificity than CA125 alone. Prospective studies with a large cohort of susceptible ovarian cancer patients will be required to expand these findings. © 2005 Wiley-Liss, Inc. [source] Virulent spores of Bacillus anthracis and other Bacillus species deposited on solid surfaces have similar sensitivity to chemical decontaminantsJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2007J-L. Sagripanti Abstract Aims:, To compare the relative sensitivity of Bacillus anthracis and spores of other Bacillus spp. deposited on different solid surfaces to inactivation by liquid chemical disinfecting agents. Methods and Results:, We prepared under similar conditions spores from five different virulent and three attenuated strains of B. anthracis, as well as spores of Bacillus subtilis, Bacillus atrophaeus (previously known as Bacillus globigii), Bacillus cereus, Bacillus thuringiensis and Bacillus megaterium. As spore-surface interactions may bias inactivation experiments, we evaluated the relative binding of different spores to carrier materials. The survival of spores deposited on glass, metallic or polymeric surfaces were quantitatively measured by ASTM standard method E-2414-05 which recovers spores from surfaces by increasing stringency. The number of spores inactivated by each decontaminant was similar and generally within 1 log among the 12 different Bacillus strains tested. This similarity among Bacillus strains and species was observed through a range of sporicidal efficacy on spores deposited on painted metal, polymeric rubber or glass. Conclusions:, The data obtained indicate that the sensitivity of common simulants (B. atrophaeus and B. subtilis), as well as spores of B. cereus, B. thuringiensis, and B. megaterium, to inactivation by products that contain either: peroxide, chlorine or oxidants is similar to that shown by spores from all eight B. anthracis strains studied. Significance and Impact of the Study:, The comparative results of the present study suggest that decontamination and sterilization data obtained with simulants can be safely extrapolated to virulent spores of B. anthracis. Thus, valid conclusions on sporicidal efficacy could be drawn from safer and less costly experiments employing non-pathogenic spore simulants. [source] Brood size and environmental conditions sex-specifically affect nestling immune response in the European starling Sturnus vulgarisJOURNAL OF AVIAN BIOLOGY, Issue 6 2005Eunice H. Chin In sexually size-dimorphic species, the larger sex can be more sensitive to stressful environmental conditions, often resulting in reduced growth and elevated mortality rates. Development of the immune system is regarded as highly resource dependent, and recent data suggest that nestling passerines experience a possible resource-based trade-off between growth and immunity. Given the hypothesized importance of maximizing growth for the larger sex, the corresponding immune system may also exhibit similar sensitivity to limited resources. To better understand how natural variation in brood size and resources might differentially affect growth and immune function in nestlings of a sexually size-dimorphic species, we examined the relationship between brood size and inter-sexual differences in cell-mediated immunity (CMI) and survival in European starling Sturnus vulgaris nestlings where males are larger in both mass and structural size. We hypothesized that male CMI response should be negatively impacted by increasing sibling competition (brood size), especially during periods of low resource availability. In a year of reduced parental provisioning rates and reduced chick growth rates, male offspring exhibited the predicted negative relationship, whereas female CMI response was unaffected. However, in a year of improved provisioning rates and chick growth, neither sex exhibited a negative relationship between immune response and brood size. Thus, natural variation in brood size can affect sex-specific immunity differently in offspring of a sexually size-dimorphic passerine. However, this relationship appears resource-dependent, suggesting that the hypothesized resource-based trade-off may be compensated for in years of adequate resource abundance. [source] Development of an Antibody Hapten-Chip System for Detecting the Residues of Multiple Antibiotic Drugs,JOURNAL OF FORENSIC SCIENCES, Issue 4 2009Ailiang Chen M.Sc. Abstract:, The abuse of antibiotic drugs during animal production remains a worldwide problem and the subsequent detection of the residues of various drugs present at low concentrations in complex biological matrices poses significant analytical challenges. The present study outlines a practical biochip assay system to identify antibiotic residues in different animal tissue extracts. The system uses a simple but efficient multiresidue sample extraction procedure to isolate the antibiotic residues which were then identified directly using high-affinity monoclonal antibodies presented in a competitive immunoassay with conjugated antibiotic hapten-chips. The hapten-chip can analyze six samples each for eight antibiotics on a single chip within 3 h. The analytical results with both artificial positive standard samples and the incurred samples show that the antibody hapten-chip system has a comparable accuracy and a similar sensitivity to a standard ultra performance liquid chromatography,mass spectrometry (MS)/MS assay. In conclusion, an effective analytical screening system based on antibody hapten-chip was developed for detecting multiple antibiotic residues from multiple samples. [source] Beyond bone mineral density: can existing clinical risk assessment instruments identify women at increased risk of osteoporosis?JOURNAL OF INTERNAL MEDICINE, Issue 5 2004L. E. Wehren Abstract. Objective., Although osteoporosis and fragility fracture are common amongst postmenopausal women, the extent of risk varies, and measurement of bone mineral density (BMD) is the standard tool used to diagnose and assess fracture risk. Rates of diagnosis remain relatively low, and several groups have developed instruments to help identify individuals who would most benefit from BMD testing. In this paper, we review and compare the performance of these instruments to identify those most useful in the primary care setting. Design., Review of screening instruments comprised osteoporosis clinical risk factors and comparison of the sensitivity and specificity of these algorithms. Results., Validated instruments have varying complexity, but similar sensitivity and specificity for identifying individuals who are likely to have low BMD. The area under the receiver operating characteristic curve ranges from 0.75 (SOFSURF) to 0.81 (SCORE). The simplest of the instruments (OST) uses only age and weight and has an AUC of 0.79. Conclusions., The Osteoporosis Self-assessment Tool, the simplest of the instruments, performs as well as more complex tools and, because of its simplicity, may be the most useful means for the busy clinician to identify postmenopausal women who would most benefit from BMD testing. [source] Human brain aminopeptidase A: biochemical properties and distribution in brain nucleiJOURNAL OF NEUROCHEMISTRY, Issue 1 2008Nadia De Mota Abstract Aminopeptidase A (APA) generated brain angiotensin III, one of the main effector peptides of the brain renin angiotensin system, exerting a tonic stimulatory effect on the control of blood pressure in hypertensive rats. The distribution of APA in human brain has not been yet studied. We first biochemically characterized human brain APA (apparent molecular mass of 165 and 130 kDa) and we showed that the human enzyme exhibited similar enzymatic characteristics to recombinant mouse APA. Both enzymes had similar sensitivity to Ca2+. Kinetic studies showed that the Km (190 ,mol/L) of the human enzyme for the synthetic substrate- l -glutamyl-,-naphthylamide was close from that of the mouse enzyme (256 ,mol/L). Moreover, various classes of inhibitors including the specific and selective APA inhibitor, (S)-3-amino-4-mercapto-butyl sulfonic acid, had similar inhibitory potencies toward both enzymes. Using (S)-3-amino-4-mercapto-butyl sulfonic acid, we then specifically measured the activity of APA in 40 microdissected areas of the adult human brain. Significant heterogeneity was found in the activity of APA in the various analyzed regions. The highest activity was measured in the choroids plexus and the pineal gland. High activity was also detected in the dorsomedial medulla oblongata, in the septum, the prefrontal cortex, the olfactory bulb, the nucleus accumbens, and the hypothalamus, especially in the paraventricular and supraoptic nuclei. Immunostaining of human brain sections at the level of the medulla oblongata strengthened these data, showing for the first time a high density of immunoreactive neuronal cell bodies and fibers in the motor hypoglossal nucleus, the dorsal motor nucleus of the vagus, the nucleus of the solitary tract, the Roller nucleus, the ambiguus nucleus, the inferior olivary complex, and in the external cuneate nucleus. APA immunoreactivity was also visualized in vessels and capillaries in the dorsal motor nucleus of the vagus and the inferior olivary complex. The presence of APA in several human brain nuclei sensitive to angiotensins and involved in blood pressure regulation suggests that APA in humans is an integral component of the brain renin angiotensin system and strengthens the idea that APA inhibitors could be clinically tested as an additional therapy for the treatment of certain forms of hypertension. [source] Measurement of spin-lattice relaxation times and chemical exchange rates in multiple-site systems using progressive saturationMAGNETIC RESONANCE IN MEDICINE, Issue 1 2007Craig J. Galbán Abstract A new method for measuring spin-lattice relaxation times and chemical exchange (CE) rate constants in multiple-site exchanging systems is described. The method, chemical exchange and T1 measurement using progressive saturation (CUPS), was applied to determine T1s and analyze phosphorus exchange among phosphocreatine (PCr), ATP, and inorganic phosphate (Pi), mediated by creatine kinase (CK) and ATP synthase, using 31P-MRS. Two-site exchange was analyzed in vitro and in the rat leg, and three-site exchange was analyzed in the rat heart. Data were fitted to a model of progressive saturation incorporating T1 relaxation and CE. For the in vitro system at 8.45T, we found T1(PCr) = 2.86 s and T1(,-ATP) = 1.72 s. For the rat gastrocnemius at 1.9T, we found T1(PCr) = 6.60 s and T1(,-ATP) = 2.06 s. For the rat heart at 9.4T, we found T1(PCr) = 3.35 s, T1(,-ATP) = 0.69 s, and T1(Pi) = 1.83 s. All of these values were within 20% of literature values. Similarly, the determined exchange rates were in the same range as published values. Using simulations, we compared CUPS with transient saturation transfer as a method for measuring T1s and rates. The two methods showed similar sensitivity to noise. We conclude that CUPS is a viable alternative for measuring T1s and CE rates in exchanging systems. Magn Reson Med 58:8,18, 2007. © 2007 Wiley-Liss, Inc. [source] Sensitivity of Botrytis cinerea from vegetable greenhouses to boscalidPLANT PATHOLOGY, Issue 4 2007C. Q. Zhang Between 2004 and 2006, 228 isolates of Botrytis cinerea from two regions in China were characterized for baseline sensitivity to boscalid, a new active ingredient that interferes with succinate ubiquinone reductase in the electron transport chain. The isolates showed similar sensitivity in different years and regions. Baseline sensitivities were distributed as unimodal curves with mean EC50 values of 1·07 (± 0·11) and 0·42 (± 0·05) mg L,1 for inhibition of mycelial growth and conidial germination, respectively. Laboratory studies were conducted to evaluate the risk of development of resistance to boscalid. Boscalid-resistant mutants were obtained by UV-treatment at lower frequencies and with smaller resistance factors than pyrimethanil-resistant mutants. All boscalid-resistant mutants were also significantly more sensitive to Qo inhibitors than their wild-type parents and showed reduced sporulation in vitro and pathogenicity on aubergine leaves. The results suggested that the risk of resistance developing for boscalid was lower than for pyrimethanil. However, as B. cinerea is a high-risk pathogen, appropriate precautions against resistance development should be taken. Synergism between the activity of boscalid and that of kresoxim-methyl was observed. [source] Should liquid-based cytology be performed prior to colposcopy?AUSTRALIAN AND NEW ZEALAND JOURNAL OF OBSTETRICS AND GYNAECOLOGY, Issue 6 2009A comparison of the accuracy, cost in a tertiary referral setting, unsatisfactory rates Objective:, To compare the use of liquid-based cytology (LBC) with conventional cytology (CC) in the assessment cervical intraepithelial neoplasia (CIN) prior to colposcopy. Design:, Retrospective Cohort Study. Methods:, Liquid-based cytology and CC findings were compared with colposcopic assessment and directed cervical biopsy in terms of sensitivity and specificity for high grade lesions only and for any abnormalities. The degree of correlation was sought. Secondary outcomes were unsatisfactory rate and cost. Results:, A total of 1961 women had colposcopy of whom 528 had cervical biopsy. LBC and CC have similar sensitivity and specificity for both high-grade lesions and any abnormalities. In comparison with cervical biopsy, LBC and CC sensitivity for high-grade disease was 89.1% and 88.6% respectively and for any abnormalities, the sensitivity was 86.6% and 87.0%. Specificity for high-grade disease was 83.1% and 84.7% and for any abnormalities, the specificity was 53.8% and 56.4%. The unsatisfactory rate was significantly lower in LBC 4.38% compared to 1.84% (P < 0.001). However, the use of LBC was associated with an additional cost of A$1496 for each unsatisfactory smear avoided. Conclusion:, In high prevalence setting, LBC showed no statistically significant difference in sensitivity and specificity from CC for the detection of CIN. A reduction in unsatisfactory smears was evident, but at significant additional cost. [source] Differential cytotoxicity of novel somatostatin and dopamine chimeric compounds on bronchopulmonary and small intestinal neuroendocrine tumor cell linesCANCER, Issue 4 2008Mark Kidd PhD Abstract BACKGROUND. Survival rates for gastrointestinal (GI) and bronchopulmonary (BP) neuroendocrine tumors (NETs) have not significantly altered (overall 67%, 5-year survival) in 30 years (1973-2004), whereas the incidence has increased (, 1000%) in the same time frame. No effective or specific antineoplastic agent is available for treatment, although somatostatin analogs inhibit tumor secretion. Given the coexistence of somatostatin and dopamine regulatory receptors on NET cells, the antiproliferative efficacy as well as the signaling and transcriptional targets of their ligands were evaluated. METHODS. The cytotoxic effects of 12 somatostatin/dopamine compounds were evaluated in 3 NET cell lines, and real-time polymerase chain reaction and enzyme-linked immunoadsorbent assay studies were performed to delineate antiproliferative signaling pathways. RESULTS. The atypical BP-NET, NCI-H720, was most sensitive to the sst5 analog BIM23206 (half-maximal concentration, 2.4 pM) and demonstrated similar sensitivity to lanreotide and the sst2 analog BIM23120. The typical BP-NET, NCI-H727, was most sensitive to BIM23120 (0.7 nM) and to the pan-somatostatin receptor analog (BIM23A779). The GI-NET, KRJ-I, was most sensitive to sst2,5 analogs lanreotide (1 nM) and BIM23244 (7.4 nM). Lanreotide activated extracellular signal regulated kinase-1/2 phosphorylation and p21WAF1/CIP1 transcription, but inhibited Ki-67 transcription. NCI-H720 was most sensitive to the sst2,5 - and D2 -selective compound BIM23A761 (4.2 nM), as was NCI-H727 (5.5 nM). KRJ-I did not respond to any chimeric analog. BIM23A761 activated c-Jun N-terminal kinase signaling and caused inhibition of Ki-67 transcription. P21WAF1/CIP1 transcription was activated only in NCI-H727 cells. CONCLUSIONS. The different responses of each individual cell line suggested that NETs from different locations arising from different neuroendocrine cells may require cell-specific antiproliferative agents based on the unique receptor profile of individual lesions. Cancer 2008. © 2008 American Cancer Society. [source] Diagnostic accuracy of Heidelberg Retina Tomograph III classifications in a Turkish primary open-angle glaucoma populationACTA OPHTHALMOLOGICA, Issue 1 2010Banu Bozkurt Abstract. Purpose:, This study aimed to evaluate the diagnostic accuracy of Moorfields regression analysis (MRA) and the glaucoma probability score (GPS) in primary open-angle glaucoma (POAG) and to measure the level of agreement between the two algorithms in classifying eyes as normal or abnormal in a Turkish population. Methods:, We prospectively selected 184 healthy subjects and 158 subjects with POAG, who underwent an ophthalmological examination, visual field analysis and imaging with the Heidelberg Retina Tomograph II, using HRT III software, Version 3.0. The diagnostic accuracies of the two classifications were measured when the borderline was taken as either normal (highest specificity criteria) or abnormal (highest sensitivity criteria). The agreement between them was calculated using the unweighted kappa (,) coefficient. Results:, Optic nerve head topographic parameters showed statistically significant differences between the control and POAG groups (p < 0.001). The parameters with the highest area under the receiver operating characteristic curves were global GPS (0.86), cup : disc area (0.85), rim : disc area (0.85) and vertical cup : disc (0.85). According to the highest specificity criteria, MRA had a sensitivity of 67.7% and a specificity of 95.1%, whereas the GPS had a sensitivity of 70.9% and a specificity of 88.0%. According to the highest sensitivity criteria, MRA had a sensitivity of 81.0% and a specificity of 75.0%, whereas the GPS had a sensitivity of 89.2% and a specificity of 57.6%. A moderate agreement of 68% (233 eyes) with a , coefficient of 0.51 was found between MRA and the GPS. Conclusions:, The GPS automated classification showed similar sensitivity to MRA, but considerably lower specificity, when applied in a Turkish population. [source] Simultaneous voiding cystourethrography and voiding urosonography reveals utility of sonographic diagnosis of vesicoureteral reflux in childrenACTA PAEDIATRICA, Issue 12 2003M Nakamura Aim: To evaluate the diagnostic potential of voiding urosonography (VUS) compared with fluoroscopic voiding cystourethrography (VCUG) under identical conditions and to evaluate potential reasons for false-negative VUS results, particularly regarding bladder concentrations of the US contrast agent, Levovist. Methods: Fifty-six paediatric patients (M/F 34/22, mean age 2.3 y, age range 1 mo-14 y) underwent simultaneous VUS and VCUG under identical conditions. The bladder was filled by simultaneous administration of Levovist and the X-ray contrast medium, DIP Conray. Levovist concentrations in bladders were calculated using amounts of Levovist injected and total DIP Conray infused when reflux was first observed in either procedure. Results: Sensitivities of VUS and VCUG for detection of vesicoureteral reflux (VUR) were both 86%, assuming that VUR detected by either method represented a true-positive, and no reflux by either method represented a true-negative. Patients under 24-mo of age displayed a better VUS sensitivity, of 94%. Levovist concentrations in bladders ranged from 1.8% to 23%, with older children tending to demonstrate increased bladder capacity and lower concentration. All VUS false-negative units displayed Levovist bladder concentrations of less than 5%. Conclusion: The present simultaneous study suggests that: 1) the two techniques demonstrate similar sensitivity for detection of reflux; 2) sustained Levovist bladder concentrations of below 5% may not allow detection of reflux on VUS; and 3) VUS represents a suitable technique, particularly for small children whose bladder capacity is not so large. [source] | |||||||||||||||||||