bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation into temperature rise and volumetric entropy generation rate in fluid and porous subsystems
Authors: Yilbas B.S. , Bin Mansoor S.
Published: June 2010

Temperature differential occurs between the fluid phase and the solid phase in porous medium. The heat transfer in fluid and solid phases in a porous medium becomes non‐equilibrium and the fluid phase as well as the solid phase in the porous medium separates thermally forming two subsystems. In the present study, temperature fields in fluid and solid phases in the porous medium are predicted using the two‐equation model. Entropy generation rates in each phase as well as entropy generation rate due to thermal exchange between phases are computed. It is found that temperatures of both subsystems are different along the axial distance at the mid‐plane and this difference varies with time. Volumetric entropy generation rate due to thermal exchange between both phases is considerably less than that generated in each phase. © 2010 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/htj.20298
Boiling heat transfer coefficient of R22 and an HFC/HC refrigerant mixture in a fin‐and‐tube evaporator of a window air conditioner
Authors: Herbert Raj M. , Mohan Lal D.
Published: June 2010

The commonly used refrigerant in unitary type air conditioners is R22 and its phase out schedule in developing countries is to commence from 2015. Many alternatives to R22 are found in published literature in which R407C has similar characteristics to those of R22 except for its zeotropic nature. However, R407C which is an HFC is made compatible with the mineral oil lubricant in the system compressor by the addition of 20% of HC. This HFC/HC mixture called the M20 refrigerant mixture is reported to be a retrofit refrigerant for R22. Though its latent heat value is greater than that of R22, its refrigerating capacity is lower when it is used to retrofit R22 window air conditioners. Hence, a heat transfer analysis was conducted in the evaporator of a room air conditioner, for practically realized heat flux conditions during standard performance testing. The tests were conducted as per the BIS and ASHRAE standards. Kattan–Thome–Favrat maps are used to confirm the flow patterns, which prevail inside the fin‐and‐tube evaporator in the tested operating conditions. It is revealed that the heat transfer coefficient/heat fluxes are poorer for M20 because of the lower mass flow rate and higher vapor fraction at the entry of the evaporator than that of R22 in the prevailing operating conditions. The heat transfer coefficients of the M20 refrigerant mixture under various test conditions are lower in the range of 14% to 56% than those of R22. © 2010 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/htj.20299
Liquid film flow rising along the outer surface of the rotating cone
Authors: Adachi Takahiro , Sato Naoya , Kobari Naoto , Hori Toshihiro
Published: June 2010

We have investigated fluid flow characteristics of liquid film flow rising along the outer surface of a rotating cone. The fluid is given a centrifugal force due to the rotation of the cone, while strong surface tension maintains the centrifugal force at the outer surface of the liquid film flow. Therefore, the fluid does not spread outward from the cone, but goes up along it. We have visualized the interesting flow phenomena with a high‐speed video camera. In addition, we have measured the correlation between the wetted radius, rotation rate of the cone, and flow rate of the rising film flow. © 2010 Wiley Periodicals, Inc. Heat Trans Asian Res; 39(7): 492–496, 2010; Published online 2 June 2010 in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/htj.20307
Heat removable limit for nuclear fuel
Authors: Morooka Shinichi , Kudo Yoshiro , Hotta Akitoshi
Published: June 2010

The imminent revival of nuclear power has progressed in recent years and many countries, including the U.S., are planning construction of new NPPs (nuclear power plants). This movement is called “Nuclear Renaissance.”

In the fuel assembly design of a nuclear reactor, the heat‐removal limit (critical power, critical heat flux), below which generated heat can be removed without a sudden rise of fuel temperature, is one of the design limits. From the perspective of ensuring reliability and safety of nuclear reactors, it is very important to predict this limit with sufficient precision.

The purpose of this paper is to review the following items:

State‐of‐the‐art simulation techniques to predict the heat‐removal limit

Cutting‐edge design concepts to enhance the heat‐removal limit

A challenge beyond the heat‐removal limit by introducing the post‐BT (boiling transition) criteria

In this paper, aiming for more efficient processes and a higher level of optimization in the nuclear fuel design, the importance of some key physical models and relevant experimental data is focused in order to improve prediction accuracy of the heat transfer including the post BT region. © 2010 Wiley Periodicals, Inc. Heat Trans Asian Res; 39(7): 482–491, 2010; Published online 2 June 2010 in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/htj.20308
Regulatory T cells in tumor immunity
Authors: Nishikawa Hiroyoshi , Sakaguchi Shimon
Published: June 2010

Recent studies have revealed that Foxp3+CD25+CD4+ regulatory T cells (Tregs), which are physiologically engaged in the maintenance of immunological self‐tolerance, play critical roles for the control of antitumor immune responses. For example, a large number of Foxp3+Tregs infiltrate into tumors, and systemic removal of Foxp3+Tregs enhances natural as well as vaccine‐induced antitumor T‐cell responses. Tregs are recruited to tumor tissues via chemokines, such as CCL22 binding to CCR4 expressed by Tregs. They appear to expand and become activated in tumor tissues and in the draining lymph nodes by recognizing tumor‐associated antigens as well as normal self‐antigen expressed by tumor cells. These results indicate that cancer vaccines targeting tumor‐associated self‐antigens may potentially expand/activate Tregs and hamper effective antitumor immune responses, and that tumor immunity can therefore be enhanced by depleting Tregs, attenuating Treg suppressive function, or rendering effector T cells refractory to Treg‐mediated suppression. Recent attempts have indeed demonstrated that combinations of monoclonal antibodies capable of modulating Treg functions synergistically enhance antitumor activity and are more effective than a single monoclonal antibody therapy. Combination therapy targeting a variety of molecules expressed in antigen‐presenting cells, effector T cells and Tregs is envisaged to be a promising anticancer immunotherapy.
Trends in the incidence of cancer in the Sousse region, Tunisia, 1993–2006
Authors: Missaoui Nabiha , Trabelsi Amel , Parkin Donald M. , Jaidene Lilia , Chatti Daniel , Mokni Moncef , Korbi Sadok , Hmissa Sihem
Published: June 2010

In this article, we analyzed trends in incidence rates of the major cancer sites for a 14‐year period, 1993–2006, in the Sousse region localized in the centre of Tunisia. Five‐year age‐specific rates, crude incidence rates (CR), world age‐standardized rates (ASR), percent change (PC) and annual percent change (APC) were calculated using annual data on population size and its estimated age structure. A total of 6,975 incident cases of cancer were registered, with a male to‐female sex ratio of 1.4:1. ASRs showed stable trends (−0.1% in males, and +1.0% in females). The leading cancer sites in rank were lung, breast, lymphoma, colon‐rectum, bladder, prostate, leukemia, stomach and cervix uteri. For males, the incidence rates of lung, bladder and prostate cancers remained stable over time. While, cancers of colon‐rectum showed a marked increase in incidence (APC: +4.8%; 95% CI: 1.2%, 8.4%) and non‐Hodgkin's lymphoma (NHL) showed a notable decline (APC: −4.4%; 95% CI: −8.2, −0.6). For females, cancers of the breast (APC: +2.2%; 95% CI: 0.4%, 4.0%) and corpus uteri (APC: +7.4%; 95% CI: 2.8%, 12.0%) showed a marked increase in incidence during the study period, while the cervix uteri cancer decreased significantly (APC: −6.1%; 95% CI: −9.2%, −3.0%). The results underline the increasing importance of cancer as a cause of mortality and morbidity in Tunisia. Our findings justify the need to develop effective program aiming at the control and prevention of the spread of cancer amongst Tunisian population.
Aryl hydrocarbon receptor activation during pregnancy, and in adult nulliparous mice, delays the subsequent development of DMBA‐induced mammary tumors
Authors: Wang Tao , Gavin Heather M. , Arlt Volker M. , Lawrence B. Paige , Fenton Suzanne E. , Medina Daniel , Vorderstrasse Beth A.
Published: June 2010

2,3,7,8‐Tetrachlorodibenzo‐p‐dioxin (TCDD), the prototypic ligand for the aryl hydrocarbon receptor (AhR), promotes tumor formation in some model systems. However, with regard to breast cancer, epidemiological and animal studies are inconclusive as to whether exposure increases tumor incidence or may instead be protective. We have previously reported that mice exposed to TCDD during pregnancy have impaired differentiation of mammary tissue, including decreased branching and poor development of lobuloalveolar structures. Because normal pregnancy‐induced mammary differentiation may protect against subsequent neoplastic transformation, we hypothesized that TCDD‐treated mice would be more susceptible to chemical carcinogenesis after parturition. To test this, mice were treated with TCDD or vehicle during pregnancy. Four weeks later, 7,12‐dimethylbenz[a]anthracene (DMBA) was administered to induce mammary tumor formation. Contrary to our hypothesis, TCDD‐exposed parous mice showed a 4‐week delay in tumor formation relative to controls, and they had a lower tumor incidence throughout the 27‐week time course. The same results were obtained in nulliparous mice given TCDD and DMBA on the same schedule. We next addressed whether the delayed tumor incidence was a reflection of decreased tumor initiation, by testing the formation of DMBA‐DNA adducts and preneoplastic lesions, induction of cytochrome P450s, and cell proliferation. None of these markers of tumor initiation differed between vehicle‐ and TCDD‐treated animals. The expression of CXCL12 and CXCR4 was also measured to address their possible role in tumorigenesis. Taken together, our results suggest that AhR activation by TCDD slows the promotion of preneoplastic lesions to overt mammary tumors.
Cell Lysis of Cyanobacteria and Its Implications for Nutrient Dynamics
Authors: Ye Linlin , Wu Xiaodong , Tan Xiao , Shi Xiaoli , Li Daming , Yu Yang , Zhang Min , Kong Fanxiang
Published: June 2010

The dynamics of nutrients, such as phosphorus, nitrogen, and carbohydrates, during cyanobacteria cell lysis was investigated under darkness incubation in the laboratory. The cell lysis rate of cyanobacteria sampled from Lake Taihu was measured using an esterase assay. Based on particulate esterase activity, the calculated cyanobacteria lysis rate was 0.094 d–1. During 30 days of darkness incubation, Chlorophyll a concentration decreased from 56 μg L–1 to 2.0 μg L–1. Parallel to this, total particulate carbohydrate concentration decreased rapidly. The fluctuation of dissolved organic carbon concentration was a function of the production of non‐carbohydrate by cyanobacteria and the decomposition of carbohydrate by bacteria. Total dissolved carbohydrates and dissolved polysaccharides concentrations showed a similar pattern, declining at the beginning of the experiment and keeping relatively stable, thereafter. In contrast, the concentration of dissolved monosaccharides remained constant during the entire process. The concentrations of NH4+ and PO43– increased at the early stage, and then decreased afterwards. A gradual decrease in NO3– concentration after day 8 indicated that anaerobic conditions might be produced during the cell lysis process. The present results demonstrated cyanobacteria cell lysis has a big influence on the nutrient status of the surrounding water. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of the Environmental Factors on the Caloric Content of Benthic and Phytophilous Invertebrates in Neotropical Reservoirs in the Paraná State, Brazil
Authors: Moretto Bagatini Yara , Benedito Evanilde , Higuti Janet
Published: June 2010

The complexity of the relations between the organisms and the environment are reflected through the energy content. So we tested the hypothesis on body energy content variation in invertebrates and its relation with some environmental factors (season, habitat type, trophic status and trophic guild). We expected higher energy values for phytophilous fauna, rainy season, in reservoirs with higher trophic levels and for herbivorous invertebrates. The results showed the influence of seasonality and trophic status of the reservoir on the energy content of invertebrates, which was higher in the rainy season and in the mesotrophic reservoirs, due to the input of allochthonous material during this season, confirming our initial prediction. A higher caloric content was recorded for carnivorous and detritivorous invertebrates. The differences between the trophic guilds were primarily related to the opportunistic feeding behavior, which may be considered as one of the main factors controlling the energy flow of benthic and phytophilous invertebrates. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Preliminary evaluation of acute toxicity of 188Re–BMEDA–liposome in rats
Authors: Liu Chi‐Mou , Chang Chih‐Hsien , Chang Ya‐Jen , Hsu Chin‐Wei , Chen Liang‐Cheng , Chen Hsiao‐Lin , Ho Chung‐Li , Yu Chia‐Yu , Chang Tsui‐Jung , Chiang Tung‐Chuan , Lee Te‐Wei
Published: June 2010

Liposomes can selectively target cancer sites and carry payloads, thereby improving diagnostic and therapeutic effectiveness and reducing toxicity. To evaluate therapeutic strategies, it is essential to use animal models reflecting important safety aspects before clinical application. The objective of this study was to investigate acute radiotoxicity of 188Re‐N,N‐bis (2‐mercaptoethyl)‐N′,N′‐diethylethylenediamine (BMEDA)‐labeled pegylated liposomes (188Re–BMEDA–liposome) in Sprague–Dawley rats. Rats were administered with 188Re–BMEDA–liposome, normal saline as blank or non‐radioactive liposome as vehicle control via intravenous injection and observed for 14 days. Examinations were conducted with respect to mortality, clinical signs, food consumption, body weight and hematological and biochemical analyses. In addition, gross necropsy, histopathological examinations and cytogenetic analyses were also performed. None of the rats died and no clinical sign was observed during the 14‐day study period. Rats administered with 188Re–BMEDA–liposome at dosage of 185 MBq displayed a significant weight loss compared with the control from study day (SD) 1 to SD 4, and the white blood cell count reduced to 5–10% of initial value (female: 18.55 ± 6.58 to 0.73 ± 0.26 × 103 µl−1; male: 14.52 ± 5.12 to 1.43 ± 0.54 × 103 µl−1) 7 days‐post injection, but were found to have recovered on SD 15. There were no significant differences in biochemical parameters and histopathological assessments between the 188Re–BMEDA–liposome‐treated and control groups. The frequencies of dicentric chromosomes were associated with dosage of 188Re–BMEDA–liposome. The information generated from this study on acute toxicity will serve as a safety reference for further subacute toxicity study in rats and human clinical trials. Copyright © 2010 John Wiley & Sons, Ltd.
Distinct immunohistomorphologic changes in periprosthetic hip tissues from historical and highly crosslinked UHMWPE implant retrievals
Authors: Baxter Ryan M. , Ianuzzi Allyson , Freeman Theresa A. , Kurtz Steven M. , Steinbeck Marla J.
Published: June 2010

Assessment of immune response to implant wear debris in periprosthetic tissue following total hip arthroplasty suggests that multiple factors are involved in the loss implant function. The current study investigated wear debris and the associated immunohistomorphologic changes in tissues from nine patients with historical (gamma air‐sterilized) and nine highly crosslinked UHMWPE implant components. Paraffin embedded tissue sections were evaluated for the presence of histiocytes, giant cells, fibrocartilage/bone, and necrosis. To determine the incidence, degree and co‐localization of immunohistomorphologic changes and wear, overlapping full‐field tissue arrays were collected in brightfield and polarized light. The historical cohort tissues predominantly showed histiocytes associated with significant accumulations of small wear (0.5–2 μm), and giant cells associated with large wear (≥2 μm). Frequently, focal regions of necrosis were observed in association with wear debris. For the highly crosslinked cohort, inflammation and associated wear debris were limited, but in tissues from patients revised after implantation times of >2 years a response was observed. Whereas significant amounts of fibrocartilage/bone were observed in patients at earlier implantation times. In both cohorts, tissue responses were more extensive in the retroacetabular or proximal femoral regions. The current findings suggest that wear debris‐induced inflammation may be a major contributor to the loss of implant function for both the historical and highly crosslinked cohorts, but it is not the primary cause of early implant loosening. This study highlights the importance of using a more quantitative and standardized assessment of immunohistomorphologic responses in periprosthetic tissues, and emphasizes differences in specific anatomical regions of individual patient tissues. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.
Role of histone acetylation in the development of diabetic retinopathy and the metabolic memory phenomenon
Authors: Zhong Qing , Kowluru Renu A.
Published: June 2010

Hyperglycemia is considered as one of the major determinants in the development of diabetic retinopathy, but the progression of retinopathy resists arrest after hyperglycemia is terminated, suggesting a metabolic memory phenomenon. Diabetes alters the expression of retinal genes, and this continues even after good glycemic control is re‐instituted. Since the expression of genes is affected by chromatin structure that is modulated by post‐translational modifications of histones, our objective is to investigate the role of histone acetylation in the development of diabetic retinopathy, and in the metabolic memory phenomenon. Streptozotocin‐induced rats were maintained either in poor glycemic control (PC, glycated hemoglobin, GHb >11%) or good glycemic control (GC, GHb <6%) for 12 months, or allowed to be in PC for 6 months followed by in GC for 6 months (PC‐GC). On a cellular level, retinal endothelial cells, the target of histopathology of diabetic retinopathy, were incubated in 5 or 20 mM glucose for 4 days. Activities of histone deacetylase (HDAC) and histone acetyltransferase (HAT), and histone acetylation were quantified. Hyperglycemia activated HDAC and increased HDAC1, 2, and 8 gene expressions in the retina and its capillary cells. The activity HAT was compromised and the acetylation of histone H3 was decreased. Termination of hyperglycemia failed to provide any benefits to diabetes‐induced changes in retinal HDAC and HAT, and histone H3 remained subnormal. This suggests “in principle” the role of global acetylation of retinal histone H3 in the development of diabetic retinopathy and in the metabolic memory phenomenon associated with its continued progression. J. Cell. Biochem. 110: 1306–1313, 2010. © 2010 Wiley‐Liss, Inc.
Novel regulation of 25‐hydroxyvitamin D3 24‐hydroxylase (24(OH)ase) transcription by glucocorticoids: Cooperative effects of the glucocorticoid receptor, C/EBPβ, and the Vitamin D receptor in 24(OH)ase transcription
Authors: Dhawan Puneet , Christakos Sylvia
Published: June 2010

Glucocorticoid‐induced bone loss has been proposed to involve direct effects on bone cells as well as alterations in calcium absorption and excretion. Since vitamin D is important for the maintenance of calcium homeostasis, in the present study the effects of glucocorticoids on vitamin D metabolism through the expression of 24(OH)ase, an enzyme involved in the catabolism of 1,25(OH)2D3, were examined. Injection of vitamin D replete mice with dexamethasone (dex) resulted in a significant induction in 24(OH)ase mRNA in kidney, indicating a regulatory effect of glucocorticoids on vitamin D metabolism. Whether glucocorticoids can affect 24(OH)ase transcription is not known. Here we demonstrate for the first time a glucocorticoid receptor (GR) dependent enhancement of 1,25(OH)2D3‐induced 24(OH)ase transcription. Dex treatment of GR and vitamin D receptor (VDR) transfected COS‐7 cells and dex treatment of osteoblastic cells (in which VDR and GR are present endogenously) potentiated 1,25(OH)2D3‐induced 24(OH)ase transcription. In addition, GR was found to cooperate with C/EBPβ to enhance VDR‐mediated 24(OH)ase transcription. Using the rat 24(OH)ase promoter with the C/EBP site mutated, GR‐mediated potentiation of 1,25(OH)2D3‐induced 24(OH)ase transcription was inhibited. Immunoprecipitation indicated that that GR can interact with C/EBPβ and ChIP/re‐ChIP analysis showed that C/EBPβ and GR bind simultaneously to the 24(OH)ase promoter. These findings indicate a novel mechanism whereby glucocorticoids can alter VDR‐mediated 24(OH)ase transcription through functional cooperation between C/EBPβ and GR that results in an enhanced ability of C/EBPβ to cooperate with VDR in the regulation of 24(OH)ase. J. Cell. Biochem. 110: 1314–1323, 2010. © 2010 Wiley‐Liss, Inc.
Long chain‐polyunsaturated fatty acids modulate membrane phospholipid composition and protein localization in lipid rafts of neural stem cell cultures
Authors: Langelier Bénédicte , Linard Alain , Bordat Christian , Lavialle Monique , Heberden Christine
Published: June 2010

Rat neural stem cells/neural progenitors (NSC/NP) are generally grown in serum‐free medium. In this study, NSC/NP were supplemented with the main long‐chain polyunsaturated fatty acids (PUFAs) present in the brain, arachidonic acid (AA), or docosahexaenoic acid (DHA), and were monitored for their growth. Lipid and fatty acid contents of the cells were also determined. Under standard conditions, the cells were characterized by phospholipids displaying a highly saturated profile, and very low levels of PUFAs. When cultured in the presence of PUFAs, the cells easily incorporated them into the phospholipid fraction. We also compared the presence of three membrane proteins in the lipid raft fractions: GFR and connexin 43 contents in the rafts were increased by DHA supplementation, whereas Gβ subunit content was not significantly modified. The restoration of DHA levels in the phospholipids could profoundly affect protein localization and, consequently, their functionalities. J. Cell. Biochem. 110: 1356–1364, 2010. © 2010 Wiley‐Liss, Inc.
Non‐muscle myosin IIB helps mediate TNF cell death signaling independent of actomyosin contractility (AMC)
Authors: Flynn Patrick G. , Helfman David M.
Published: June 2010

Non‐muscle myosin II (NM II) helps mediate survival and apoptosis in response to TNF‐alpha (TNF), however, NM II's mechanism of action in these processes is not fully understood. NM II isoforms are involved in a variety of cellular processes and differences in their enzyme kinetics, localization, and activation allow NM II isoforms to have distinct functions within the same cell. The present study focused on isoform specific functions of NM IIA and IIB in mediating TNF induced apoptosis. Results show that siRNA knockdown of NM IIB, but not NM IIA, impaired caspase cleavage and nuclear condensation in response to TNF. NM II's function in promoting cell death signaling appears to be independent of actomyosin contractility (AMC) since treatment of cells with blebbistatin or cytochalasin D failed to inhibit TNF induced caspase cleavage. Immunoprecipitation studies revealed associations of NM IIB with clathrin, FADD, and caspase 8 in response to TNF suggesting a role for NM IIB in TNFR1 endocytosis and the formation of the death inducing signaling complex (DISC). These findings suggest that NM IIB promotes TNF cell death signaling in a manner independent of its force generating property. J. Cell. Biochem. 9999: 1365–1375, 2010. © 2010 Wiley‐Liss, Inc.
Inhibition of β‐catenin/Tcf signaling by flavonoids
Authors: Park Seyeon , Choi Jaemin
Published: June 2010

Functional activation of β‐catenin/T‐cell factor (Tcf) signaling has been implicated in human carcinogenesis. We identified the inhibitory effect of various polyphenolic flavonoid compounds against β‐catenin/Tcf signaling in β‐catenin‐activated cells. Genistein, kaempferol, isorhamnentin, and baicalein inhibited the transcriptional activity of β‐catenin/Tcf in HEK293 cells transiently transfected with a constitutively active mutant β‐catenin gene. To investigate the inhibitory mechanism, electrophoresis mobility shift assay, immunoprecipitation, and Western blot experiments were performed. The shift assay showed that the binding of Tcf complexes with its specific DNA‐binding sites was suppressed by four kinds of flavonoids. Immunoprecipitation analysis also showed that the binding of β‐catenin to Tcf‐4 was also disrupted by these flavonoids. Western blot analysis showed a decreased level of β‐catenin in nucleus caused by genistein. Genistein also decreased phosphorylation of Akt and GSK3β. Taken together, these results suggest that the polyphenolic flavonoids genistein, kaempferol, isorhamnentin, and baicalein are negative regulators of β‐catenin/Tcf signaling and their inhibitory mechanism is related to the decreased binding of β‐catenin/Tcf complexes to consensus DNA. J. Cell. Biochem. 110: 1376–1385, 2010. © 2010 Wiley‐Liss, Inc.
Mechanism of dihydrofolate reductase downregulation in melanoma by 3‐O‐(3,4,5‐trimethoxybenzoyl)‐(−)‐epicatechin
Authors: Sánchez‐del‐Campo Luís , Chazarra Soledad , Montenegro María F. , Cabezas‐Herrera Juan , Rodríguez‐López José Neptuno
Published: June 2010

In our search to improve the stability and cellular absorption of tea polyphenols, we synthesized 3‐O‐(3,4,5‐trimethoxybenzoyl)‐(−)‐epicatechin (TMECG), which showed high antiproliferative activity against melanoma. TMECG downregulates dihydrofolate reductase (DHFR) expression in melanoma cells and we detail the sequential mechanisms that result from this even. TMECG is specifically activated in melanoma cells to form a stable quinone methide (TMECG‐QM). TMECG‐QM has a dual action on these cells. First, it acts as a potent antifolate compound, disrupting folate metabolism and increasing intracellular oxidized folate coenzymes, such as dihydrofolate, which is a non‐competitive inhibitor of dihydropterine reductase, an enzyme essential for tetrahydrobiopterin (H4B) recycling. Such inhibition results in H4B deficiency, endothelial nitric oxide synthase (eNOS) uncoupling and superoxide production. Second, TMECG‐QM acts as an efficient superoxide scavenger and promotes intra‐cellular H2O2 accumulation. Here, we present evidence that TMECG markedly reduces melanoma H4B and NO bioavailability and that TMECG action is abolished by the eNOS inhibitor Nω‐nitro‐L‐arginine methyl ester or the H2O2 scavenger catalase, which strongly suggests H2O2‐dependent DHFR downregulation. In addition, the data presented here indicate that the simultaneous targeting of important pathways for melanoma survival, such as the folate cycle, H4B recycling, and the eNOS reaction, could represent an attractive strategy for fighting this malignant skin pathology. J. Cell. Biochem. 110: 1399–1409, 2010. © 2010 Wiley‐Liss, Inc.
Odontoblast‐targeted Bcl‐2 overexpression impairs dentin formation
Authors: Zhang Wenjian , Ju Jun , Gronowicz Gloria
Published: June 2010

Apoptosis has been described extensively in tooth development, which is under tight control of multiple apoptosis regulators, including anti‐apoptotic protein Bcl‐2. However, it is totally unclear how Bcl‐2 is related to odontogenesis, especially dentinogenesis. Using a transgenic mouse Col2.3Bcl‐2 in which human Bcl‐2 was overexpressed in odontoblasts, the effect of Bcl‐2 on dentinogenesis was investigated. Overexpression of Bcl‐2 was detected by immunohistochemistry and Western blot. Odontoblast apoptosis was evaluated by TUNEL and Western blot detection of cleaved caspase‐3. Odontoblast differentiation was assessed by real‐time PCR detection of dentin matrix expression. Dentin mineralization was evaluated by micro‐CT in vivo, and alizarin red S staining and calcium content analysis in vitro. Bcl‐2 was found to be overexpressed in odontoblasts and prevent their apoptosis. Odontoblast differentiation and mineralization was inhibited by Bcl‐2, as evidenced by lower expressions of DMP‐1, OC, and DSPP, and decreased odontoblast mineralization in vitro, as well as decreased dentin thickness and mineral density in vivo when compared to the wild‐type animals. Inhibition of odontoblast differentiation by Bcl‐2 occurs, at least partially, via a suppression of MEK‐ERK1/2 signaling pathway. In conclusion, Bcl‐2 overexpression prevents odontoblast apoptosis and impairs dentin formation, partially via an inhibition of odontoblast differentiation. This study revealed some novel functions of Bcl‐2 in dentinogenesis in addition to its anti‐apoptotic effect, which shed some light on the genetic complexity of tooth development. J. Cell. Biochem. 111: 425–432, 2010. © 2010 Wiley‐Liss, Inc.
A multilevel investigation of neighborhood effects on parental warmth
Authors: Tendulkar Shalini A. , Buka Stephen , Dunn Erin C. , Subramanian S.V. , Koenen Karestan C.
Published: June 2010

Although researchers recognize that social contexts shape parenting behaviors, the relationship between neighborhood environment and parenting remains poorly understood. To address this gap, we investigated the associations between compositional and contextual (structural, social, and safety) characteristics of neighborhoods and parental warmth. Data came from the Project on Human Development in Chicago Neighborhoods (PHDCN) Study and the 1990 Census. Results of multilevel linear regression analyses suggested that most of the unexplained variation in warmth resulted from compositional differences between caregivers within neighborhoods. We also found significant unexplained neighborhood variation in warmth after adjusting for numerous compositional variables, though our neighborhood variables did not explain this remaining variation. Other compositional or contextual variables may account for this neighborhood level variation. Findings suggest that although differences between caregivers explain most of the between‐neighborhood variation in parental warmth, neighborhood environment is important. These findings highlight the importance of the neighborhood in studies of parenting. © 2010 Wiley Periodicals, Inc.
Violence exposure and depressive symptoms among adolescents and young adults disconnected from school and work
Authors: Mendelson Tamar , K. Turner Alezandria , Tandon S. Darius
Published: June 2010

The psychological effects of exposure to different types of violence among urban adolescents and young adults are not yet well understood. This study investigated exposure to neighborhood violence, relationship violence, and forced sex among 677 urban African Americans aged 16–23 enrolled at an employment and training center. We assessed prevalence of each violence exposure type, the relation of each exposure type to depressive symptoms, and the extent to which exposure to multiple violence types is additively associated with depressive symptoms. Potential gender differences were also explored. Nearly 60% of our sample reported violence exposure, with males reporting more neighborhood violence and females reporting more forced sex. For both genders, each violence exposure domain was independently associated with depressive symptoms, and exposures in multiple domains had an additive effect on depressive symptom levels. These findings have implications for developing strategies to improve mental health outcomes among urban adolescents and young adults. © 2010 Wiley Periodicals, Inc.
Coping with the personal loss of having a parent with mental illness: young adults' narrative accounts of spiritual struggle and strength
Authors: Maunu Aleisha , Stein Catherine H.
Published: June 2010

The present study examines the personal accounts of nine young adults who have parents living with mental illness. Adults' experience of personal loss due to their parents' mental illness and perceptions of their religious faith journey and spiritual struggles are described. Overall, young adults who reported experiencing more personal loss due to their parents' mental illness also reported feeling more confused on their faith journey, and reported experiencing more spiritual struggle relative to participants who reported experiencing less personal loss. Regardless of level of personal loss, all participants identified positive personal attributes that resulted from coping with their parents' illness, including a greater sense of independence, personal strength, and compassion. © 2010 Wiley Periodicals, Inc.
Disclosure in 3D of slit‐membrane as well as ‐strands, and en‐face basal lamina in situ of renal glomerulus of normal rats in embedment‐free section transmission electron microscopy
Authors: Kondo Hisatake
Published: June 2010

With higher contrast and transparency due to the absence of epon and stereo‐viewing effect due to thicker sections than conventional electron microscopy as methodological advantages, the renal glomerular slits were re‐examined in embedment‐free section electron microscopy. In addition to clear demonstration of strands bridging the slits in forms of ladders with highly irregular intervals and various extension‐directions and length, this study disclosed clearly for the first time in the “section” TEM thin sheets which partially spanned the slit together with the strand‐ladders. No strands were found to align in forms of typical zippers in normal kidney. Furthermore, en‐face ultrastructure of the basal lamina in situ was clearly demonstrated in superimposed sites of the endothelial fenestrae with the slits. Microsc. Res. Tech. 74:142–147, 2011. © 2010 Wiley‐Liss, Inc.
Silk‐elastinlike protein polymers improve the efficacy of adenovirus thymidine kinase enzyme prodrug therapy of head and neck tumors
Authors: Greish Khaled , Frandsen Jordan , Scharff Stephanie , Gustafson Joshua , Cappello Joseph , Li Daqing , O'Malley Bert W. , Ghandehari Hamidreza
Published: June 2010

Background

Adenoviral‐directed enzyme prodrug therapy is a promising approach for head and neck cancer gene therapy. The challenges faced by this approach, however, comprise transient gene expression and dissemination of viruses to distant organs.

Methods

We used recombinant silk‐elastinlike protein polymer (SELP) matrices for intratumoral delivery of adenoviruses containing both thymidine kinase‐1 and luciferase genes in a nude mouse model of JHU‐022 head and neck tumor. Hydrogels made from two SELP analogues (47K and 815K), with similar silk to elastinlike block ratios but different block lengths, were studied for intratumoral viral delivery. Tumor‐bearing mice were followed up for tumor progression and luciferase gene expression concomitantly for 5 weeks. Polymer safety was evaluated through body weight change, blood count, and liver and kidney functions, in addition to gross and microscopic histological examination.

Results

SELP‐815K analogues efficiently controlled the duration and extent of transfection in tumors for up to 5 weeks with no detectable spread to the liver. An approximately five‐fold greater reduction in tumor volume was obtained with matrix‐mediated delivery compared to intra‐tumoral injection of adenoviruses in saline. SELP matrix proved safe in all injected mice compared to the control group.

Conclusions

The SELP‐controlled gene delivery approach could potentially improve the anticancer activity of virus‐mediated gene therapy at the same time as limiting viral spread to normal organs. Copyright © 2010 John Wiley & Sons, Ltd.
10th international symposium on the synthesis and applications of isotopes and isotopically labelled compounds – poster presentations Session 19, Sunday, June 14 to Thursday, June 18, 2009
Authors: Wheeler William
Published: June 2010

The poster session is a series of papers dealing with a conglomeration of all of the previous sessions. Cristian Postolache, the fourth of the Wiley Young Scientist Award winners gave a Poster in this session. Copyright © 2010 John Wiley & Sons, Ltd.
Evaluation of topographical and geographical effects on some climatic parameters in the Central Anatolia Region of Turkey
Authors: Apaydin Halit , Anli Alper S. , Ozturk Fazli
Published: June 2010

A two‐phase research was implemented to determine the effect of topography on climate parameters by using spatial interpolation and conventional statistical procedures in non‐homogeneous topography. The primary set of climate data for the Central Anatolia Region includes monthly mean global solar radiation, sunshine duration, surface air temperature, relative humidity, wind speed and rainfall, recorded from 1976 to 2005.

In the first phase, the effect of elevation on climate parameters was evaluated. For this purpose, kriging and co‐kriging geostatistical interpolation techniques were compared to determine which one of the two techniques was more successful in determining the spatial distribution of climate parameters in variable topography. The inclusion of elevation as a covariate resulted in reduction of errors on sunshine duration, temperature and wind speed. On the basis of these error values, there is a relationship between elevation and sunshine duration, temperature and wind speed.

In the second phase, multiple regression equations were developed to determine the effect of topography on annual mean values of climate factors. The highest correlation (−0.76) was found between solar radiation and latitude. The most effective factors were latitude and elevation. They alone explain 57% of the variability for sunshine duration and 56% for temperature, respectively. The multiple regression results were more significant than were the individual, pairwise correlation relationships. The mostly explained factor was temperature. Its variability was explained by latitude, elevation, aspect and slope as a ratio of 81.7%. Separate regression models for each data set and both response variables varied in their ability to explain variability in the response, withR2values between 0.125 and 0.817. Copyright © 2010 Royal Meteorological Society
Variability of regional snow cover in spring over western Canada and its relationship to temperature and circulation anomalies
Authors: Bao Zhenhao , Kelly Richard , Wu Renguang
Published: June 2010

This study documents the variability of spring snow cover over the western Canadian Prairies and Northern Boreal Forest and its relationship to sea surface temperature (SST) over the North Pacific and atmospheric circulation over the North Pacific–North America. The work is based on monthly snow cover extent (SCE) estimates derived from Advanced Very High Resolution Radiometer data during 1972–2008. Results show that the SCE along eastern parts of the Canadian Rocky Mountains has the largest variance during March and April. Two regional SCE indices are defined using area mean SCE anomalies over the region of 47–53°N, 104–111°W (SCE‐A) and 55–60°N, 111–120°W (SCE‐B) based on the leading empirical orthogonal function (EOF) patterns of SCE in March and April, respectively. These two SCE indices are not only significantly correlated with simultaneous and preceding winter 500 hPa heights over mid‐latitude northwestern North America and central North Pacific but also with SST in mid‐latitude eastern North Pacific in preceding autumn and winter. Furthermore, it is found that the SST anomalies in the mid‐latitudes along the western coast of North America in the preceding autumn–winter influence the 500 hPa height over northwestern North America in April and cause the variations of SCE‐B. Finally, it is shown that the SCE‐B can be used as a climatic index to characterize the connection of SCE with the regional skin temperature in late spring and early summer. Copyright © 2010 Royal Meteorological Society
Regionality of monsoon onset in South America: a three‐stage conceptual model
Authors: Nieto‐Ferreira Rosana , Rickenbach Thomas M.
Published: June 2010

The evolution of monsoon onset across South America has complex temporal and regional variability that are controlled by local and remote land–ocean–atmosphere processes. In this study, a three‐stage conceptual model for the onset of the South American monsoon season is proposed based on a rain threshold analysis and a rotated empirical orthogonal function (REOF) analysis of the Global Precipitation Climatology Project version 2 (GPCP‐v2) dataset. This two‐pronged approach allowed the identification of regions of South America that share a common seasonal cycle of rainfall variability and likely have a common mechanism for monsoon onset.

According to this model, the first stage of onset starts around pentad 59 (October 18–22) when precipitation begins in the northwestern part of the continent and gradually progresses towards the south and southeast. The second stage is marked by the abrupt establishment of the South Atlantic Convergence Zone (SACZ). This stage occurs on average around pentad 61 (October 28–November 1). The third stage of monsoon onset involves the late arrival of the monsoon to the mouth of the Amazon River, associated with the slow migration of the Atlantic Intertropical Convergence Zone (ITCZ). This final stage of onset occurs on average by pentad 73 (December 27–31). This three‐stage model of onset provides a useful framework for the study of regional differences in monsoon onset mechanisms, a subject that is further explored in two companion studies. Copyright © 2010 Royal Meteorological Society
Trends in temperature, diurnal temperature range and sunshine duration in Northeast India
Authors: Jhajharia Deepak , Singh Vijay P.
Published: June 2010

Trends in maximum (Tmax), minimum (Tmin) and mean (Tmean) temperatures; diurnal temperature range (DTR = Tmax − Tmin); and sunshine duration at eight sites in Northeast (NE) India were investigated. Three sites observed decreasing trends in DTR corresponding to annual, seasonal (pre‐monsoon and monsoon) and monthly (September) time scales. On the other hand, DTR increases were also observed at other three sites in monsoon and post‐monsoon seasons as well as in the months of June, October and December. The sites showing DTR decreases (increases) witnessed either increasing trends in Tmin (Tmax) or decreasing trends in Tmax (Tmin), with Tmax (Tmin) showing either no trend or increasing at a smaller rate than Tmin (Tmax). Temperature remained practically trendless in winter and pre‐monsoon seasons over NE India. However, temperature increases were observed in monsoon and post‐monsoon seasons. Decreasing trends in sunshine duration were observed mainly on annual, seasonal (winter and pre‐monsoon) and monthly (January, February and March) time scales. Concomitant decreases in sunshine duration may be one of the potential causes of the observed DTR decreases over NE India. Copyright © 2010 Royal Meteorological Society
Present‐day interannual variability of surface climate in CMIP3 models and its relation to future warming
Authors: Scherrer Simon C.
Published: June 2010

Interannual variability (IAV) of 2m temperature (T), sea level pressure (SLP) and precipitation (P) in the CMIP3 20th century model simulations are compared with IAV in observational and reanalysis data sets using standard deviation based variability indices. Further, the relation between the representation of T IAV and the amplitude of future warming is investigated. In the Northern Hemisphere (NH) extratropics, T and SLP IAV are (in contrast to P) in general well represented although a few models perform much worse than others. General problem regions are: (1) sea ice boundary regions, where well‐known biases in the mean states exist; and (2) the Pacific Ocean and Central Africa where SLP IAV is consistently underestimated. T and SLP IAV discrepancies are often found in similar regions and are large in well‐known bias problem regions in the tropics and subtropics and high mountain regions. ‘Bad’ IAV representation also occurs in regions with small biases. T IAV is in general better reproduced over land than over sea and in the extratropics than in the tropics. Among the ‘good’ IAV models there is no robust relation between the tropics (sea only) and the extratropics (land only). The relation between the model's ability to correctly represent T IAV and projected temperature changes is slightly negative (more warming for better IAV representation) but except for the NH summer season not significant when the worst models in terms of IAV representation are omitted. This suggests that aggregated over large regions (with exception of NH summer) no robust relations are found between the model's ability to correctly represent T IAV and the projected temperature change. Copyright © 2010 Royal Meteorological Society
The influence of trees and grass on outdoor thermal comfort in a hot‐arid environment
Authors: Shashua‐Bar Limor , Pearlmutter David , Erell Evyatar
Published: June 2010

The effects of vegetation on human thermal stress in a hot‐arid region were tested in two semi‐enclosed urban spaces with various combinations of mature trees, grass, overhead shading mesh and paving. The index of thermal stress was calculated hourly from measured meteorological data in the studied sites to evaluate thermal comfort in the different spaces based on radiative and convective pedestrian–environment energy exchanges and sweat efficiency, and expressed on a thermal sensation scale ranging from ‘comfortable’ to ‘very hot’. The efficiency of water use in providing improved comfort was gauged for each of the vegetative landscaping treatments by comparing the total evapotranspiration with the reduction in thermal stress, both expressed in terms of their values in equivalent energy. While conditions in a paved, unshaded courtyard were found to be uncomfortable throughout the daytime hours (with half of these hours defined by severe discomfort), each of the landscape treatments made a clear contribution to improved thermal comfort. With shading, either by trees or mesh, discomfort was reduced in duration by over half and limited in maximum severity when the shading was placed above paving. When combined with grass, both shading mechanisms yielded comfortable conditions at all hours. In both cases, the effect of trees was more pronounced than that of the mesh, but by a small margin. With unshaded grass, ‘hot’ conditions in the courtyard were restricted to a short period in mid‐afternoon, a considerable improvement over unshaded paving, attributable mainly to the lower radiant surface temperatures. Copyright © 2010 Royal Meteorological Society