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In this paper, we describe development of a high-throughput, highly sensitive method based on Lab Chip CGE-SDS platform for purity determination and characterization of virus-like particle (VLP) vaccines. A capillary gel electrophoresis approach requiring about 41 s per sample for analysis and demonstrating sensitivity to protein initial concentrations as low as 20 μg/mL, this method has been used previously to evaluate monoclonal antibodies, but this application for lot release assay of VLPs using this platform is unique. The method was qualified and shown to be accurate for the quantitation of VLP purity. Assay repeatability was confirmed to be less than 2% relative standard deviation of the mean (% RSD) with interday precision less than 2% RSD. The assay can evaluate purified VLPs in a concentration range of 20-249 μg/mL for VEE and 20-250 μg/mL for EEE and WEE VLPs.

The interstitial chromosome (chr.) 1q21-q22 region is frequently amplified in human cancers, where it has been reported to carry prognostic significance for patients. We attempted to delineate chr. 1q21-q22 for affected gene(s) in hepatocellular carcinoma (HCC) by array-CGH and detected copy number gains of ρ-guanine nucleotide exchange factor-H1 (GEF-H1) as most significant event. Gene expression evaluation in the HCC cohort indicated common up-regulations of GEF-H1 in 64% tumours compared to adjacent non-tumoural liver (64/100; paired t-test p < 0.0001). Moreover, GEF-H1 over-expressions correlated with microvascular invasion and advanced-stage tumours (p < 0.05). High GEF-H1 levels also predict shorter disease-free and overall survival of HCC patients (p < 0.03). Functional knock-down of GEF-H1 by RNAi indicated marked reduction in cell invasion through matrigel and an inhibition of cell migration (p < 0.035), but an effect on cell viability was not apparent. More interestingly, a mesenchymal-epithelial transition (MET) was readily observed in GEF-H1 knock-down cells, where a concomitant re-expression of epithelial markers (E-cadherin and cytokeratin 18) and cell adhesion proteins (α-catenin and γ-catenin) was found but down-regulation of mesenchymal features (N-cadherin, vimentin and fibronectin). This phenotype was accompanied by reduced filamentous actin polymerizations and diminution of the stress fibre formation. In addition, reduced active form of GTP-RhoA, together with its downstream effectors, including cleaved ROCK1 and phosphorylated MLC2, were also detected in GEF-H1-depleted cells. Taken together, our findings underscore a potent oncogenic role for GEF-H1 in promoting the metastatic potentials of HCC, possibly through activation of RhoA signalling and the EMT phenomenon.

Homozygous deletion screening has been widely utilized to define tumour suppressor genes (TSGs) in cancers. Although these biallelic deletions are infrequent, their identification has facilitated the discovery of many important TSGs. We have systematically examined the genome of hepatocellular carcinoma (HCC), a highly malignant tumour that is rapidly fatal, for the presence of homozygous deletions. Array-CGH analysis on early passage of HCC cultures and cell lines led us to identify six homozygous deleted (HD) regions. A high concordance between array-CGH and expression of HD genes was demonstrated, where crystallin Lambda1 (CRYL1; located on chromosome 13q12.11) displayed the most frequent down-regulation. We found that reduced mRNA expression of CRYL1 was common in HCC tumours when compared with their adjacent non-tumoural liver (p = 0.0097). Significant associations could also be drawn between repressed CRYL1 and advanced tumour staging, increased tumour size, and shorter disease-free survival of patients (p < 0.037). Moreover, homozygous deletions on CRYL1 could be detected in 36% of HCC cases, where recurrent HDs were identified on exons 1, 5, and 8. Examination of other causal events suggested histone deacetylation and promoter hypermethylation to be likely inactivating mechanisms as well. Re-expression of CRYL1 in the SK-Hep1 cell line, where biallelic loss of CRYL1 was found, induced profound inhibition of cellular proliferation and cell growth (p < 0.0015). By Annexin V staining, CRYL1 restoration readily increased pro-apoptotic cells with an induction of PARP cleavage. Flow cytometry further revealed that CRYL1 could prolong the G(2)-M phase, possibly through interruption of the Cdc2/cyclin B pathway. Given that regional chromosome 13q12-q14 loss is a causal genomic event in HCC tumourigenesis, our finding may have implications for identifying a novel TSG CRYL1 within this important locus.

Background: Different levels of positive end-expiratory pressure (PEEP) with and without a recruitment maneuver (RM) may have a significant impact on ventilator-induced lung injury but this issue has not been well addressed. Methods: Anesthetized rats received hydrochloric acid (HCl, pH 1.5) aspiration, followed by mechanical ventilation with a tidal volume of 6 ml/kg. The animals were randomized into four groups of 10 each: (1) high PEEP at 6 cm H2O with an RM by applying peak airway pressure at 30 cm H2O for 10 s every 15 min; (2) low PEEP at 2 cm H2O with RM; (3) high PEEP alone; and (4) low PEEP alone. Results: The mean arterial pressure and the amounts of fluid infused were similar in the four groups. Application of the higher PEEP improved oxygenation compared with the lower PEEP groups (P

An analysis is made of the turbulent Graetz problem with viscous energy dissipation effects in pipes with uniform wall beat flux. The effects of viscous dissipation on fully developed Nusselt numbers are studied for fluids with Prandtl numbers 1, 10, 102, 103 for Reynolds numbers between 5 × 103 and 5 × 105 with both cooling and heating conditions at the pipe wall. The viscous dissipation effects on convective turbulent heat transfer in arctic hot oil pipelines are discussed. On a fait une analyse du probleme de turbulence de Graetz en determinant les effets de la dissipation visqueuse d'energie dans des tuyaux ou un flux uniforme de chaleur s'exerce sur les parois. On a etudie les effets de la dissipation visqueuse sur des nombres de Nusselt bien mis en valeur, dans le cas de fluides dont les nombres de Prandtl etaient 1,10, 102 et 103 et les nombres de Reynolds variaient entre 5 × 103 et 5 × 105; le travail impliquait a la fois des conditions de refroidissement et de chauffage sur les parois des tuyaux. On discute les effets de la dissipation visqueuse sur le transfert convectif et turbulent de la) chaleur dans les pipe-lines qui transportent l'huile chaude dans l'Arctique.

The thermal entrance region heat transfer problem for fully developed laminar flow in curved pipes with uniform wall temperature is approached by an alternating direction implicit method for the parabolic energy equation for a flow regime with Dean number ranging from 0 to an order of 100. This work represents an extension of the classical Graetz problem in straight tubes to curved pipes. The graphical results for temperature developments in the form of temperature profiles through the horizontal and vertical planes, isothermals and local Nusselt number variations in the thermal entrance region are presented in such a way as to illustrate clearly the interaction between the secondary flow and the developing temperature field for Prandtl numbers of 0.1, 0.7, 10 and 500. For a given Dean number, the effect of Prandtl number is to shorten the thermal entrance length (I/Gz) and the temperature field develops rather rapidly with large Prandtl number. The effect of Dean number is similar to that of Prandtl number with Dean number effect becoming much more appreciable at high Prantdl numbers than at low Prandtl number. On a attaque le probleme de transfert de la chaleur dans la region ou elle penetre, dans le cas d'un ecoulement laminaire en plein fonctionnement dans des tuyaux recourbes dont la temperatures des parois etait uniforme; on a utilise a cette fin une methode implicite, en directions alternees, pour determiner l'equation d'energie parabolique d'un systeme d'ecoulement dans lequel les nombres de Dean variaient entre 0 et 100. Ledit travail represente une extension a des tuyaux recourbes du probleme classique de Graetz dans des tuyaux droits. On presente les resultats graphiques des variations de temperature sous forme de profils de temperature dans les plans horizontal et vertical, de lignes isothermes et de variations locales du nombre de Nusselt dans la region d'entree de la chaleur; on le fait de maniere a illustrer clairement l'interaction entre l'ecoulement secondaire et le champ d'evolution de la temperature, Iorsque les nombres de Prandtl sont 0.1, 0.7, 10 et 500. Pour un nombre specifique de Dean, l'effet du nombre de Prandtl, est de reduire la longueur de l'entree de la chaleur (1/Gz) et l'evolution du champ de la temperature se fait plutǒt rapidement lorsque le nombre de Prandtl est considerable. L'effet du nombre de Dean est semblable a celui du nombre de Prandtl, mais il est bien plus appreciable lorsque le nombre de Prandtl est eleve que lorsque celui-ci est faible.

The Joule-Thomson effect is known to be important in arctic gas pipelines. The Joule-Thomson effects on forced convective heat transfer in the thermal entrance region of pipes with uniform wall temperature are studied for steady fully developed turbulent gas flows by the Graetz method. Thermal entrance heat transfer results are presented for Prandtl number 0.72, Reynolds number 105 and Brinkman number ± 0.1, ± 1.0 with Joule-Thomson parameter Jμ ranging from 0 to 1.0 to cover the possible range in practical applications. Bulk temperatures and Nusselt numbers are also presented for fully developed flow with Reynolds numbers from 5 × 103 to 106. For given Prandtl and Reynolds numbers, the asymptotic Nusselt number is found to be dependent on the Joule-Thomson parameter only and is independent of Brinkman number. The fully developed bulk temperature is a linear function of Brinkman number and a linear relationship exists between the bulk temperature parameter (-θbf/Br) and the Joule-Thomson parameter Jμ for given Prandtl and Reynolds numbers. On sait que les effets de Joule et Thomson sont importants dans le cas des pipe-lines qui transportent le gaz de la region arctique; on a etudie, par la methode de Graetz et relativement aux ecoulements de gaz turbulents, stables et en pleine evolution, l'action desdits effets sur le transfert thermique convectif et force dans la region d'entree de chaleur des tuyaux a parois uniformes. Pour embrasser l'echelle possible des applications pratiques, on presente les resultats de transfert de la chaleur a l'entree de celle-ci dans le cas du nombre de Prandtl de 0.72, du nombre de Reynolds de 105 et du nombre de Brinkman de ± 0.1, ± 1.0 ainsi que du parametre de Joule et Thomson variant entre 0 to 1.0. On presente aussi les temperatures globales et les nombres de Nusselt, dans le cas d'un eoculement en plein evolution avec des nombres de Reynolds echelonnes entre 5 × 103 et 106. On a trouve que, pour des nombres donnes de Prandtl et Reynolds, le nombre asymptotique de Nusselt ne dependait que du parametre de Joule et Thomson et qu'il etait independant du nombre de Brinkman. La temperature globale de l'ecoulement en pleine evolution est une fonction lineaire du nombre de Brinkman et il existe une relation lineaire entre le parametre de temperature globale (-θbf/Br) et le parametre Ju de Joule et Thomson, dans le cas de nombres donnees de Prandtl et Reynolds.

The problem of low-Peclet-number thermal entry heat transfer for plane Poiseuille flow in parallel-plate channels with uniform but unequal wall temperatures is approached by the eigenfunction expansion method utilizing the Gram-Schmidt orthonormalization procedure. The formulation considers axial heat conduction and allows upstream heat penetration through the thermal entrance. Numerical results are obtained for the case with entrance condition parameter θ0 = 1 and Peclet number Pe = 1, 5, 10 and 50. The effect of Peclet number on temperature distributions in both upstream and downstream regions is studied. At Pe = 50, the concept of thermal boundary layer is applicable and the present series solution does not yield physically reasonable temperature distribution locally near the upper plate at the thermal entrance. The difficulty may be attributed to the nature of thermal boundary conditions at the thermal entrance and the transition from elliptic problem to parabolic problem with the increase of Peclet number. On a etudie le transfert de la chaleur, pour des nombres faibles de Peclet, dans la region d'entree thermique, lors d'nn ecoulement plan de Poiseuille dans des canaux a plaques paralleles ou les temperatures des parois etaient uniformes, mais inegales. On a employe dans ladite etude la methode d'expansion de la fonction propre, laquelle utilise la technique d'orthonormalisation de Gram et Schmidt. La formulation considere la conduction axiale de la chaleur et permet une penetration de la chaleur vers le haut par l'entree thermique. On a obtenu des resultats numeriques lorsque le parametre de la condition d'entree θ0 = 1 et que les nombres de Peclet Pe etaient 1, 5, 10 et 50. On a etudie l'effet du nombre de Peclet sur les distributions des temperatures dans les regions ou la penetration de la chaleur se faisait vers le haut et vers le bas. Lorsque le nombre de Peclet etait 50, le concept de la couche-limite de chaleur s'appliquait et la solution trouvee n'a pas fourni une distribution des temperatures qui etait physiquement raisonnable pres de la plaque superieure a l'entree thermique. On peut attribuer ladite difficulte a la nature des conditions-limites de chaleur a l'entree de celle-ci et a la transition d'un probleme elliptique a un probleme parabolique avec un accroissement du nombre de Peclet.

An analysis is made to deteimine the conditions marking the onset of longitudinal vortices in the laminar natural convection flow over a heated isothermal inclined plate. A linear stability theory based on Boussinesq approximation and without the conventional parallel-flow assumption for basic velocity and temperature profiles is employed in the derivation of perturbation equations. An iterative procedure employing a fourth order Runge-Kutta method is applied in the solution of the perturbation equations. A comparison between the neutral stability resuts obtained with and without the commonly used parallel-flow approximation in the stability theory of small disturbances shows that the parallel-flow assumption is an invalid one for the present problem. Solutions are obtained for Pr = 0.72, 1, 2, 10, 100, and ∞ and the critical Rayleigh number marking the onset of longitudinal vortices is found to be a rather weak function of Prandtl number. A comparison of the present neutral stability results for the inclination angles α = 20° ∼ 60° with experimental data reported in the literature reveals that the theory predicts critical values which are generally two orders of magnitude lower than the experimental data. On fait une analyse pour determiner les conditions qui marquent la production de tourbillons Iongitudinaux dans l'ecoulement laminaire a convection naturelle qui se fait sur une plaque inclinee chauffee d'une maniere isothermique. On emploie, dans l'etablissement des equations de perturbation, une theorie de stabilite lineaire qui est basee sur l'approximation de Boussinesq, mais est depourvue de la supposition classique d'ecoulement parallele pour la vitesse de base et les profits de temperature. On applique, dans la solution des equations de perturbation, un procede iteratif ou l'on utilise une methode de quatrieme ordre de Runge et Kutta. On montre que la supposition de l'ecoulement parallele est sans valeur dans le probleme actuel, en comparant les resultats de stabilite neutre, obtenus avec ou sans l'approximation de l'ecoulement parallele qu'on utilise couramment dans la theorie de stabilite des perturbations faibles. On obtient des solutions pour des nombres de Prandtl de 0.72, 1, 2, 10, 100 et ∞ et trouve que le nombre critique de Rayleigh qui correspond a la production des tourbillons longitudinaux est une fonction pluto't faible du nombre de Prandtl. En comparant, pour les angles d'inclinaison α = 20° ∼ 60°, les resultats actuels de la stabilite neutre avec les donnees experimentales deja publiees, on trouve que la theorie prevoit des valeurs critiques qui sont generalement inferieures de deux ordres de grandeur aux donnees experimentales.

SUMMARY: Destruction of A. niger conidiospores at 20°C (68°F) by 20 ppm NaClO and 20 ppm iodine as iodophor yielded D values of 0.61 min and 0.86, respectively at pH 3.0 and 1.31 and 2.04 min, respectively at pH 7.0. On the basis of mojar concentrations, iodine was slightly more effective than chlorine. A D value of 0.026 min was obtained with 4% NaOH at 60°C (140°F) indicating 4% NaOH at 60°C to be far more germicidal than 20 ppm of either halogen compound at 20°C. One per cent NaOH at 30°C resulted in an immediate and rapid release of amino acids presumably from the spore wall during the first 2 min of contact and a slower rate of release of RNA, with DNA released at the slowest rate.