bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical Study of Fluid Flow and Heat Transfer in Partially Heated Microchannels Using the Explicit Finite Volume Method
Authors: Chaudhuri A. , Guha C. , Dutta T. K. 
Published: March 2007

AbstractFluid flow behavior and heat transfer characteristics of pressure driven flow in partially heated microchannels have been investigated using the explicit Finite Volume Method (FVM). The developed flow solver utilizes the compressible Navier‐Stokes (NS) system of equations with Maxwell's first order slip boundary condition and the corresponding temperature jump relation derived by von Smoluchowski to achieve the solutions. The effects of Knudsen number and gas species have been studied for partially heated microchannels similar to the classical Graetz problem. The existence of nonlinear pressure distribution and dominant heat diffusion for higher Knudsen number regime are predicted by the solution. The fluid flow and heat transfer characteristics of the partially heated microchannels greatly depend on the transport properties of the medium under similar flow conditions.
Crossflow Ultrafiltration of Binary Biomolecule Mixture: Analysis of Permeate Flux, Cake Resistance and Sieving Coefficient
Authors: Salgın U. , Salgın S. 
Published: March 2007

AbstractThe aim of this paper is to demonstrate the effects of hydrodynamic conditions on the permeate flux, cake resistance and sieving coefficient in a crossflow ultrafiltration process separating biomolecules of different molecular weights. A binary mixture of L‐phenylalanine (L‐phe) and lipase was ultrafiltered through a hydrophobic polyether sulphone (PES) membrane with 10 kDa molecular weight cut‐off. The changes in permeate flux, cake layer resistance and observed sieving coefficient with different transmembrane pressures (TMP) and crossflow velocities were evaluated. The effect of TMP was examined at two different velocities (0.114 m s–1 and 0.176 m s–1) and the effect of velocity was examined at two different TMP (20 kPa and 115 kPa) for the experimental system designed. In the initial stage of the crossflow filtration, it was determined that the TMP was more effective than the velocity. The cake layer resistance increased with increasing TMP and it decreased with increasing velocity for the high TMP value of 115 kPa. A maximum of the observed sieving coefficient was achieved with increasing velocity. An increase in TMP at low inlet velocity (0.114 m s–1) affected the observed sieving coefficient positively.
Imatinib mesylate for targeting the platelet‐derived growth factor β receptor in combination with fluorouracil and leucovorin in patients with refractory pancreatic, bile duct, colorectal, or gastric cancer—A dose‐escalation Phase I trial
Authors: Al‐Batran Salah‐Eddin , Atmaca Akin , Schleyer Eberhard , Pauligk Claudia , Hosius Christian , Ehninger Gerhard , Jäger Elke 
Published: March 2007

AbstractBACKGROUND.In previous experimental models, because of its ability to inhibit the activity of platelet‐derived growth factor β receptor, imatinib decreased the interstitial fluid pressure and improved the delivery and efficacy of anticancer drugs, including fluorouracil. The objective of this Phase I study was to define the dose‐limiting toxicity (DLT) and maximum tolerated dose (MTD) of imatinib in combination with fluorouracil and leucovorin in patients with chemotherapy‐refractory gastrointestinal cancer.METHODS.A 3‐patient cohort dose‐escalating study design was used. Patients received leucovorin 200 mg/m2 followed by fluorouracil 2000 mg/m2 as a 24‐hour infusion on Days 1 and 2 combined with imatinib on Days −4, −3, −2, −1, 1, 2, 3, and 4. Cycles were repeated every 2 weeks, and the imatinib dose was escalated from 300 mg daily to 700 mg daily in 100‐mg steps.RESULTS.Thirty patients were enrolled at 5 dose levels. Frequent and dose‐dependant National Cancer Institute Common Toxicity Criteria grade 1–4 adverse events with suspected relation to the treatment were anemia (43%), nausea (33%), fluid retention (27%), elevated serum γ‐glutamyl‐transpeptidase (20%), and diarrhea. DLTs were severe neutropenia, central fluid retention, and severe nausea observed in 1 patient each, resulting in an MTD for imatinib of 600 mg per day. There were no differences in imatinib pharmacokinetics before or during chemotherapy. A minor response was observed; and signs of clinical activity, including the resolution of ascites and improvement in performance status, were noted in some patients.CONCLUSIONS.The combination of biweekly fluorouracil/leucovorin and imatinib 600 mg daily given in a week‐on/week‐off schedule was feasible and safe. Nausea and fluid retention represented the DLTs. Cancer 2007. © 2007 American Cancer Society.
XAF1 mediates apoptosis through an extracellular signal‐regulated kinase pathway in colon cancer
Authors: Yu Li Fen , Wang Jide , Zou Bing , Lin Marie C. M. , Wu Yun Lin , Xia Harry H. X. , Sun Yun Wei , Gu Qing , He Hua , Lam S. K. , Kung Hsiang Fu , Wong Benjamin C. Y. 
Published: March 2007

AbstractBACKGROUND.XIAP‐associated factor 1 (XAF1) negatively regulates the function of the X‐linked inhibitor of apoptosis protein (XIAP), a member of the IAP family that exerts antiapoptotic effects. The extracellular signal‐regulated kinase (ERK) pathway is thought to increase cell proliferation and to protect cells from apoptosis. The aim of the study was to investigate the correlation between the ERK1/2 signaling pathway and XAF1 in colon cancer.METHODS.Four human colon cancer cell lines, HCT1116 and Lovo (wildtype p53), DLD1 and SW1116 (mutant p53), were used. Lovo stable transfectants with XAF1 sense and antisense were established. The effects of dominant‐negative MEK1 (DN‐MEK1) and MEK‐specific inhibitor U0126 on the ERK signaling pathway and expression of XAF1 and XIAP proteins were determined. The transcription activity of core XAF1 promoter was assessed by dual luciferase reporter assay. Cell proliferation was measured by MTT assay. Apoptosis was determined by Hoechst 33258 staining.RESULTS.U0126 increased the expression of XAF1 in a time‐ and dose‐dependent manner. A similar result was obtained in cells transfected with DN‐MEK1 treatment. Conversely, the expression of XIAP was down‐regulated. Activity of the putative promoter of the XAF1 gene was significantly increased by U0126 treatment and DN‐MEK1 transient transfection. rhEGF‐stimulated phosphorylation of ERK appeared to have little or no effect on XAF1 expression. Overexpression of XAF1 was more sensitive to U0126‐induced apoptosis, whereas down‐regulation of XAF1 by antisense reversed U0126‐induced inhibition of cell proliferation.CONCLUSIONS.XAF1 expression was up‐regulated by inhibition of the ERK1/2 pathway through transcriptional regulation, which required de novo protein synthesis. The results suggest that XAF1 mediates apoptosis induced by the ERK1/2 pathway in colon cancer. Cancer 2007. © 2007 American Cancer Society.
The burden of liver cancer in Asians and Pacific Islanders in the Greater San Francisco Bay Area, 1990 through 2004
Authors: Chang Ellen T. , Keegan Theresa H. M. , Gomez Scarlett L. , Le Gem M. , Clarke Christina A. , So Samuel K. S. , Glaser Sally L. 
Published: March 2007

AbstractBACKGROUND.To the authors' knowledge, no previous U.S. study has examined time trends in the incidence rate of liver cancer in the high‐risk Asian/Pacific Islander population. In this study, liver cancer incidence trends were evaluated in Chinese, Filipino, Japanese, Korean, and Vietnamese men and women in the Greater San Francisco Bay Area of California between 1990 and 2004.METHODS.Populations at risk were estimated by using the cohort‐component demographic method. Annual percentage changes (APCs) in age‐adjusted incidence rates of primary liver cancer among Asians/Pacific Islanders in the Greater Bay Area Cancer Registry were calculated by using joinpoint regression analysis.RESULTS.The incidence rate of liver cancer between 1990 and 2004 did not change significantly in Asian/Pacific Islander men or women overall. However, the incidence rate declined, although the decline was not statistically significant, among Chinese men (APC, −1.6%; 95% confidence interval [95% CI], −3.4–0.3%), Japanese men (APC, −4.9%; 95% CI, −10.7–1.2%), and Japanese women (APC, −3.6%; 95% CI, −8.9–2%). Incidence rates remained consistently high for Vietnamese, Korean, and Filipino men and women. Trends in the incidence rate of hepatocellular carcinoma were comparable to those for liver cancer. Although disparities in liver cancer incidence between Asians/Pacific Islanders and other racial/ethnic groups diminished between the period from 1990 through 1994 and the period from 2000 through 2004, the disparities among Asian subgroups increased.CONCLUSIONS.Liver cancer continues to affect Asian/Pacific Islander Americans disproportionately, with consistently high incidence rates in most subgroups. Culturally targeted prevention methods are needed to reduce the high rates of liver cancer in this growing population in the U.S. Cancer 2007. © 2007 American Cancer Society.
Metrics for packet reordering—A comparative analysis
Authors: Piratla Nischal M. , Jayasumana Anura P. 
Published: March 2007

AbstractPacket reordering is an inevitable phenomenon on the Internet. An ideal metric for packet reordering should capture reordering accurately, provide insight into the nature of reordering, and help in the evaluation and analysis of reordering leading to mitigation of its adverse effects. Proposed metrics for packet reordering, namely, reorder density, reorder buffer‐occupancy density, reordering extent, andn‐reordering, overcome to various degrees the deficiencies of percentage reordering in capturing the nature and extent of reordering. These metrics vary widely in areas such as evaluation complexity, measurement technique, usage, and in the definition used for packet reordering itself. Metrics for reordering are evaluated using a framework consisting of a set of both essential and desirable attributes of reorder metrics. The attributes include the ability to capture reordering, sensitivity to lost and duplicate packets in reorder measurements, usefulness, simplicity, and evaluation complexity. Finally, the characterization of packet reordering using these metrics is discussed, using sets of measurements carried over the Internet. Copyright © 2007 John Wiley & Sons, Ltd.
Estrogen mediation of injury‐induced cell birth in neuroproliferative regions of the adult zebra finch brain
Authors: Lee Diane W. , Fernando Gowry , Peterson R. Scott , Allen Timothy A. , Schlinger Barney A. 
Published: March 2007

AbstractEstrogens influence neuronal differentiation, migration, and survival in intact brains. In injured brains, estrogens can also be neuroprotective. In Experiment 1, following a unilateral penetrating injury to the hippocampus (HP), adult female zebra finches were injected once with BrdU to label mitotic cells then sacrificed 2 h, 1 day, or 7 days postinjection. Cell proliferation was dramatically enhanced in the ipsilateral HP, as well as in neuroproliferative areas including the subventricular zone (SVZ) proximal to the injury. This increase was seen at all time points investigated. Ovariectomy (OVX) substantially suppressed proliferation bilaterally especially in the SVZ indicating that gonadal hormones influenced cell proliferation in both the intact and injured hemisphere. To determine if estrogens were directly involved, estrogen was depleted in Experiment 2 through either OVX or administration of the aromatase inhibitor fadrozole (FAD). Birds were implanted with estradiol or blank followed 2 weeks later by a unilateral penetrating lesion to the HP. Injury‐induced substantial proliferation, which was again significantly suppressed bilaterally in both OVX and FAD birds. Estrogen replacement reversed this effect in FAD but not OVX birds therefore the suppression following OVX may be due in part to nonestrogenic influences. Suppression of cell birth in FAD birds was indeed due to the removal of endogenous sources of estrogen. Results therefore indicate that estrogens are directly involved in the brain's response to injury and may be acting to provide a rich environment for the production and perhaps protection of new cells. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007.
Functional proteomics in Ciona intestinalis: A breakthrough in the exploration of the molecular and cellular mechanism of ascidian development
Authors: Inaba Kazuo , Nomura Mamoru , Nakajima Ayako , Hozumi Akiko 
Published: March 2007

AbstractAscidians have been providing a unique experimental system for a variety of fields, including reproductive biology, developmental biology, neurobiology, immunology, and evolutional biology. Recent progress in the genome sequencing of Ciona intestinalis has led to the development of a great tool for investigating the gene functions and expressions involved in several biological events in ascidians. The disclosure of genomic information has ushered in the postgenomic era, spearheaded by extensive protein analysis. The characterization of the function, localization, and molecular interaction of cellular proteins results in a more direct description of the molecular mechanism underlying several biological processes. Proteomics in ascidians, however, has just recently appeared and is not well established yet. In this study, we give an outline of the technical processes used in proteomics and review the recent status of ascidian proteomics. Developmental Dynamics 236:1782–1789, 2007. © 2007 Wiley‐Liss, Inc.
Functional expression of aquaporins in embryonic, postnatal, and adult mouse lenses
Authors: Varadaraj Kulandaiappan , Kumari Sindhu S. , Mathias Richard T. 
Published: March 2007

AbstractAquaporin 0 (AQP0) and AQP1 are expressed in the lens, each in a different cell type, and their functional roles are not thoroughly understood. Our previous study showed that these two AQPs function as water transporters. In order to further understand the functional significance of these two different aquaporins in the lens, we investigated their initiation and continued expression. AQP0 transcript and protein were first detected at embryonic stage (E) 11.25 in the differentiating primary fiber cells of the developing lens; its synthesis continued through the adult stage in the secondary fiber cells. Low levels of AQP1 expression were first seen in lens anterior epithelial cells at E17.5; following postnatal day (P) 6.5, the expression gradually progressed towards the equatorial epithelial cells. In the postnatal lens, the increase in membrane water permeability of epithelial cells and lens transparency coincides with the increase in AQP1 expression. AQP1 expression reaches its peak at P30 and continues through the adult stage both in the anterior and equatorial epithelial cells. The enhancement in AQP1 expression concomitant with the increase in the size of the lens suggests the progression in the establishment of the lens microcirculatory system. In vitro and in vivo studies show that both aquaporins share at least one important function, which is water transport in the lens microcirculatory system. However, the temporal expression of these two AQPs suggests an apparently unique role/s in lens development and transparency. To our knowledge, this is the first report on the expression patterns of AQP0 and AQP1 during lens development and differentiation and their relation to lens transparency. Developmental Dynamics 236:1319–1328, 2007. © 2007 Wiley‐Liss, Inc.
Validating in utero electroporation for the rapid analysis of gene regulatory elements in the murine telencephalon
Authors: Langevin Lisa Marie , Mattar Pierre , Scardigli Raffaella , Roussigné Myriam , Logan Cairine , Blader Patrick , Schuurmans Carol 
Published: March 2007

AbstractWith the ultimate goal of understanding how genetic modules have evolved in the telencephalon, we set out to modernize the functional analysis of cross‐species cis‐regulatory elements in mouse. In utero electroporation is rapidly replacing transgenesis as the method of choice for gain‐ and loss‐of‐function studies in the murine telencephalon, but the application of this technique to the analysis of transcriptional regulation has yet to be fully explored and exploited. To empirically define the developmental stages required to target specific populations of neurons in the dorsal telencephalon, or pallium, which gives rise to the neocortex in mouse, we performed a temporal and spatial analysis of the migratory properties of electroporated versus birth‐dated cells. Next, we compared the activities of two known Ngn2 enhancers via transgenesis and in utero electroporation, demonstrating that the latter technique more faithfully reports the endogenous telencephalic expression pattern observed in an Ngn2lacZ knock‐in line. Finally, we used this approach to test the telencephalic activities of a series of deletion constructs comprised of the zebrafish ER81 upstream regulatory region, allowing us to identify a previously uncharacterized enhancer that displays cross‐species activity in the murine piriform cortex and lateral neocortex, yet not in more medial domains of the forebrain. Taken together, our data supports the contention that in utero technology can be exploited to rapidly examine the architecture and evolution of pallial‐specific cis‐regulatory elements. Developmental Dynamics 236:1273–1286, 2007. © 2007 Wiley‐Liss, Inc.
Nr2e3 and Nrl can reprogram retinal precursors to the rod fate in Xenopus retina
Authors: McIlvain Vera A. , Knox Barry E. 
Published: March 2007

AbstractTransformation of undifferentiated progenitors into specific cell types is largely dependent on temporal and spatial expression of a complex network of transcription factors. Here, we examined whether neural retina leucine zipper (Nrl) and photoreceptor‐specific nuclear receptor Nr2e3 transcription factors contribute to cell fate determination. We cloned the Xenopus Nr2e3 gene and showed that its temporal and spatial expression is similar to its mammalian ortholog. We tested its in vivo function by misexpressing these transcription factors in Xenopus eye primordia, demonstrating that either human Nr2e3 or Nrl directed photoreceptor precursors to become rods at the expense of cones. Furthermore, overexpression of Xenopus Nrl dramatically increased the number of lens fibers, whereas human Nrl did not, suggesting evolutionary divergence of function of the Nrl gene family. Misexpression of Nrl and Nr2e3 together were more effective than either transcription factor alone in directing precursors to the rod fate. Developmental Dynamics 236:1970–1979, 2007. © 2007 Wiley‐Liss, Inc.
Macrophage migration inhibitory factor is essential for allergic asthma but not for Th2 differentiation
Authors: Magalhães Elizabeth S. , Mourao‐Sa Diego S. , Vieira‐de‐Abreu Adriana , Figueiredo Rodrigo T. , Pires Ana L. , Farias‐Filho Francisco A. , Fonseca Bruna P. F. , Viola João P. B. , Metz Christine , Martins Marco A. , Castro‐Faria‐Neto Hugo C. , Bozza Patrícia T. , Bozza Marcelo T. 
Published: March 2007

AbstractMacrophage migration inhibitory factor (MIF) is increased in asthmatic patients and plays a critical role in the pathogenesis of asthma. We show here that mice lacking MIF failed to develop airway hyper‐responsiveness (AHR), tissue eosinophilia, and mucus metaplasia. Analysis of the bronchoalveolar fluids revealed a substantial reduction of IL‐13, eotaxin and cysteinyl‐leukotrienes. The lack of these cardinal features of asthma in MIF–/– mice occurs regardless of high concentrations of IL‐4 in the lung and OVA‐specific IgE in the serum. Antigen‐specific lymphocyte proliferation and IL‐13 production were similarly increased in the draining lymph nodes of OVA‐immunized and challenged MIF–/– mice compared to WT, but were reduced in the spleen of MIF–/–, thus indicating differential roles of MIF in these compartments. Stimulation of naive CD4+ cells with anti‐CD3 antibody demonstrated that MIF–/– cells produced increased amounts of IFN‐γ and IL‐4 compared to WT CD4+ cells. Finally, treatment of sensitized BALB/c mice with neutralizing anti‐MIF antibody abrogated the development of ARH and airway inflammation without affecting the production of Th2 cytokines or IgE. The present study demonstrates that MIF is required for allergic inflammation, adding important elements to our knowledge of asthma pathogenesis and suggesting that neutralization of MIF might be of therapeutic value in asthma.
On‐line coupling of solid‐phase microextraction to commercial CE‐MS equipment
Authors: Santos Bricio , Simonet Bartolomé M. , Ríos Ángel , Valcárcel Miguel 
Published: March 2007

AbstractWe developed a new interface for the on‐line coupling of a fiber for solid‐phase microextraction (SPME) with a CE system with an electrospray interface for MS detection. The on‐line interface was a modification of a split‐flow interface typically used for coupling flow systems to CE. The modification consists of an additional channel closed with a septum that permits the introduction of the fiber in the interface, right at the inlet region of the separation capillary. The interface was designed to be used with commercial fibers. Although commercial fibers can be used directly, we recommend cutting the stationary phase and using fibers with a 2‐mm stationary phase. The system was tested for the analysis of tetracycline antibiotic residues, viz., tetracycline, oxytetracycline and doxycycline in soils. The overall accuracy was assessed by regression analysis of spiked samples, showing successful results at a 95% confidence level. The reproducibility, expressed as RSD, was 5.3% and the LOD of tetracycline antibiotics in soil ranged from 2.9 to 3.2 μg/kg.
Study of recombinant cytochrome P450 2C9 activity with diclofenac by MEKC
Authors: Konečný Jiři , Juřica Jan , Tomandl Josef , Glatz Zdeněk 
Published: March 2007

AbstractCytochrome P450 2C9 (CYP2C9) is one of the most important isoforms in human liver involved in the metabolism of a large number of therapeutic agents. The aim of this paper is to demonstrate the applicability of CE for the determination of the enzymatic activity of CYP2C9 with diclofenac as a probe substrate. MEKC with SDS as a pseudostationary phase was used for this purpose. Compared to other assays, the MEKC‐based method is rapid, can be automated and requires only a small quantity of enzymes and substrate. Moreover, the enzymatic reaction can be monitored with high sensitivity and repeatability even when the reaction mixture is used for the analysis without any pretreatment. The kinetic study on the given enzymatic reaction was also performed since the basic characterization of drug biotransformation generally begins with the enzyme kinetic analysis of metabolite formation. As a result, the Michaelis constant and maximum reaction velocity were evaluated, the values 3.44 ± 0.45 μM and 19.78 ± 0.76 nmol⋅min−1nmol−1, respectively, were in agreement with the literature data. On the other hand, a slight deviation from typical Michaelis–Menten kinetics with a weak positive cooperativity was found at diclofenac concentrations below 2 μM. The same atypical kinetic behavior of CYP2C9 was also observed by other authors.