bluuebunny/crossref_metadata_2025 huggingface dataset:
Sun Tracking Systems: A Review
Authors: Lee Chia-Yen , Chou Po-Cheng , Chiang Che-Ming , Lin Chiu-Feng
Published: May 2009

The output power produced by high-concentration solar thermal and photovoltaic systems is directly related to the amount of solar energy acquired by the system, and it is therefore necessary to track the sun’s position with a high degree of accuracy. Many systems have been proposed to facilitate this task over the past 20 years. Accordingly, this paper commences by providing a high level overview of the sun tracking system field and then describes some of the more significant proposals for closed-loop and open-loop types of sun tracking systems.
Cartilage Regeneration of Adipose-Derived Stem Cells in a Hybrid Scaffold from Fibrin-Modified PLGA
Authors: Wei Yiyong , Hu Hunyu , Wang Haiqiang , Wu Yinsong , Deng Lianfu , Qi Jin
Published: May 2009

Adipose-derived stem cells (ASCs) appear to be a useful stem cell population, which has been shown to possess multipotentiality. The aim of this study was to evaluate the utility of ASCs in tissue-engineered cartilage using a hybrid scaffold from fibrin-modified PLGA scaffold. ASCs were isolated from rabbit adipose tissue. The PLGA scaffold was prepared by low-temperature deposition technology and the hybrid scaffold was fabricated by a freeze-drying method. When ASCs were seeded onto fibrin-modified PLGA scaffold in vitro, enhanced cellular viability was observed compared to unmodified PLGA scaffold. The analysis of proteoglycan and collagen II revealed that fibrin-modified scaffold succeeded in inducing ASCs to differentiate into chondrocytes in vitro. A preliminary study on cartilage regeneration was also performed in vivo. Observation of histology and immunoblotting demonstrated that ASCs containing the hybrid scaffold promoted cartilage regeneration in the defects of articular cartilage much better than other groups. These results indicated that ASCs containing the hybrid scaffold are a more effective way to potentially enhance articular cartilage regeneration.
Collagenase Isoforms for Pancreas Digestion
Authors: Bertuzzi Federico , Cainarca Silvia , Marzorati Simona , Bachi Angela , Antonioli Barbara , Nano Rita , Verzaro Roberto , Ricordi Camillo
Published: May 2009

The available information concerning the characteristics and composition of collagenase batches, which are effective in the digestion of human pancreas for islet transplants, is scarce and incomplete. A large inter-and intrabatched variability in activity and efficiency of blend enzymes available for isolation has been observed. The aim of this study was to characterize enzyme blend components. Liberase batches were characterized by SDS-PAGE analyses, microelectrophoresis, and then by MALDI-TOF MS analysis. Three main bands were detected by SDS-PAGE analysis and submitted to MALDI-TOF MS analysis. Two bands were found to correspond to class I (isoform β and another of 106 kDa) and one to class II (isoform δ) collagenase. These results represent an important step towards a complete characterization of enzymes, with the final aim of identifying key components for a standardized product.
Flowers Are an important food for small apes in southern Sumatra
Authors: Lappan Susan
Published: May 2009

Flowers are included in the diets of many primates, but are not generally regarded as making an important contribution to primate energy budgets. However, observations of a number of lemur, platyrrhine, and cercopithecine populations suggest that some flower species may function as key primate fallback foods in periods of low abundance of preferred foods (generally ripe fruits), and that flowers may be preferred foods in some cases. I report heavy reliance on flowers during some study months for a siamang (Symphalangus syndactylus) population in southern Sumatra. Siamangs at Way Canguk spent 12% of feeding time eating flowers from October 2000 to August 2002, and in 1 month flower‐feeding time exceeded 40% of total feeding time. The overall availabilities of fig and nonfig fruits, flowers, and new leaves in the study area were not significant predictors of the proportion of time that siamangs spent consuming any plant part. However, flower‐feeding time was highest in months when nonfig fruit‐feeding time was lowest, and a switch from heavy reliance on fruit to substantial flower consumption was associated with a shift in activity patterns toward reduced energy expenditure, which is consistent with the interpretation that flowers may function as a fallback food for Way Canguk siamangs. Hydnocarpus gracilis, a plant from which siamangs only consume flowers, was the third‐most‐commonly consumed plant at Way Canguk (after Ficus spp. and Dracontomelon dao), and flowers from this plant were available in most months. It is possible that relatively high local availability of these important siamang plant foods is one factor promoting high siamang density in the study area. Am. J. Primatol. 71:624–635, 2009. © 2009 Wiley‐Liss, Inc.
Me3SiCl and Et3SiI‐promoted one‐pot synthesis of 1,4‐dihydropyridine derivatives
Authors: Mirza‐Aghayan Maryam , Langrodi Mahboubeh Khoshkameh , Rahimifard Mahshid , Boukherroub Rabah
Published: May 2009

An efficient synthesis of 1,4‐dihydropyridine derivatives has been achieved by the one‐pot cyclocondensation reaction of methyl 3‐aminocrotonate and a range of aldehydes in the presence of chlorotrimethylsilane as a promoter under solvent‐free conditions. The cyclocondenstion reaction requires a very short time and takes place in good to excellent yields. Furthermore iodotriethylsilane, generated in situ by the reaction of triethylsilane and methyl iodide in the presence of palladium chloride, has been investigated for the synthesis of 1,4‐dihydropyridine derivatives. This facile and efficient method affords high yields for the preparation of 1,4‐dihydropyridines at room temperature and short reaction times. Copyright © 2009 John Wiley & Sons, Ltd.
Determination of enalapril maleate and atenolol in their pharmaceutical products and in biological fluids by flow‐injection chemiluminescence
Authors: Al‐arfaj Nawal A. , Al‐Abdulkareem Eman A. , Aly Fatma A.
Published: May 2009

A chemiluminescent method using flow injection (FI) was investigated for rapid and sensitive determination of enalapril maleate and atenolol, which are used in the treatment of hypertension. The method is based on the sensitizing effect of these drugs on the Ce(IV)–sulfite reaction. The different experimental parameters affecting the chemiluminescence (CL) intensity were carefully studied and incorporated into the procedure. The method permitted the determination of 0.01–3.0 µg mL−1 of enalapril maleate in bulk form with correlation coefficient r = 0.99993, lower limit of detection (LOD) 0.0025 µg mL−1 (S/N = 2) and lower limit of quantitation (LOQ) 0.01 µg mL−1. The linearity range of atenolol in bulk form was 0.01–2.0 µg mL−1 (r = 0.99989) with LOD of 0.0003 µg mL−1 (S/N = 2) and LOQ of 0.01 µg mL−1. In biological fluids the linearity range of enalapril maleate was 0.1–2.0 µg mL−1 in both urine and serum, and for atenolol the linearity range was 0.1–1.0 µg mL−1 in both urine and serum. The method was also applied to the determination of the drugs in their pharmaceutical preparations. Copyright © 2009 John Wiley & Sons, Ltd.
Reactive oxygen species and peroxisomes: Struggling for balance
Authors: Bonekamp Nina A. , Völkl Alfred , Fahimi H. Dariush , Schrader Michael
Published: May 2009

Reactive oxygen species (ROS) can surely be considered as multifunctional biofactors within the cell. They are known to participate in regular cell functions, for example, as signal mediators, but overproduction under oxidative stress conditions leads to deleterious cellular effects, cell death and diverse pathological conditions. Peroxisomal function has long been linked to oxygen metabolism due to the high concentration of H2O2‐generating oxidases in peroxisomes and their set of antioxidant enzymes, especially catalase. Still, mitochondria have been very much placed in the centre of ROS metabolism and oxidative stress. This review discusses novel findings concerning the relationship between ROS and peroxisomes, as they revealed to be a key player in the dynamic spin of ROS metabolism and oxidative injury. An overview of ROS generating enzymes as well as their antioxidant counterparts will be given, exemplifying the precise fine‐tuning between the opposing systems. Various conditions in which the balance between generation and scavenging of ROS in peroxisomes is perturbed, for example, exogenous manipulation, ageing and peroxisomal disorders, are addressed. Furthermore, peroxisome‐derived oxidative stress and its effect on mitochondria (and vice versa) are discussed, highlighting the close interrelationship of both organelles. © 2009 International Union of Biochemistry and Molecular Biology, Inc.
Review of the mechanism of processive actin filament elongation by formins
Authors: Paul Aditya S. , Pollard Thomas D.
Published: May 2009

We review recent structural and biophysical studies of the mechanism of action of formins, proteins that direct the assembly of unbranched actin filaments for cytokinetic contractile rings and other cellular structures. Formins use free actin monomers to nucleate filaments and then remain bound to the barbed ends of these filaments as they elongate. In addition to variable regulatory domains, formins typically have formin homology 1 (FH1) and formin homology 2 (FH2) domains. FH1 domains have multiple binding sites for profilin, an abundant actin monomer binding protein. FH2 homodimers encircle the barbed end of a filament. Most FH2 domains inhibit actin filament elongation, but FH1 domains concentrate multiple profilin‐actin complexes near the end of the filament. FH1 domains transfer actin very rapidly onto the barbed end of the filament, allowing elongation at rates that exceed the rate of elongation by the addition of free actin monomers diffusing in solution. Binding of actin to the end of the filament provides the energy for the highly processive movement of the FH2 as a filament adds thousands of actin subunits. These biophysical insights provide the context to understand how formins contribute to actin assembly in cells. Cell Motil. Cytoskeleton 2009. © 2009 Wiley‐Liss, Inc.
Eigensolution of rotationally repetitive space structures using a canonical form
Authors: Kaveh A. , Nemati F.
Published: May 2009

In this paper, an efficient eigensolution is presented for calculating the buckling load and free vibration of rotationally cyclic structures. This solution uses a canonical form linear algebra that often occurs in matrices associated with graph models. A substructuring method is proposed to avoid the generation of entire matrices. Utilizing the aforementioned method, the geometric stiffness matrix is generated in an efficient time saving manner. Then solution for the eigenproblem is presented for geometric nonlinearity via the canonical form based on the block diagonalization method. In order to confirm the efficiency of the presented method, examples are solved using both the classic and the presented approaches. Comparison of the required computational time for the two methods shows that in the new approach the required computational time is reduced considerably. Copyright © 2009 John Wiley & Sons, Ltd.
Secure ubiquitous connectivity in hybrid multipath wirelessad hocnetwork
Authors: Vaidya Binod , Kim Tai‐hoon , Park Jong Hyuk , Lee Young Jae
Published: May 2009

With the increasing demand of ubiquitous computing, the interconnection of mobilead hocnetwork (MANET) to internet is also getting attractive, which is so‐called hybrid or connected MANET. Further, as the use of multipathad hocrouting protocols is favorable in many application, hybrid multipath MANET, which is a MANET with multiple routes to the Internet, will also grow. Security issues in hybrid MANET, however, are still a challenging task. This paper addresses security issues related to Internet connectivity andad hocrouting. In this paper, we present secure architecture framework for ubiquitous connectivity in hybrid multipath MANET that provides secure FA discovery as well as a secure Mobile IP registration for MN. We provide security and performance analysis for the proposed framework, and compare it with the exisitng schemes. It shows that the proposed framework is more effective than the existing schemes in terms of various parameters. Copyright © 2009 John Wiley & Sons, Ltd.
Papillary thyroid carcinoma with metastasis to the frontal skull
Authors: Feng Dian , Rhatigan Ronald , Shuja Sania , Wolfson David , Makary Raafat , Koch Kathryn , Masood Shahla
Published: May 2009

Papillary thyroid carcinoma with metastasis to the frontal skull is extremely rare. We report a case of unsuspected papillary thyroid carcinoma with frontal skull metastasis. The patient was a 62‐year‐old African American woman with presentation of a 4‐cm firm, painless, immobile, ill‐defined mass at the right forehead. Ultrasound and computer tonography detected a hypervascular and osteolytic tumor involving the skull and overlying skin. Fine‐needle aspiration was performed followed by surgical biopsy. Cytologic examination revealed the presence of hypercellular and bloody material. The neoplasm showed glandular features and was composed of clusters of round to oval cells with pinkish squamoid cytoplasm, oval nuclei and inconspicuous nucleoli on smears and sections of cell block. With immunocytochemical stain, the neoplastic cells were positive for pancytokeratin and vimentin and focally positive for EMA, while they were negative for S100, HMB45, Melan‐A, CD34, GFAP, CD10, LCA, RCC and CD138. The diagnosis was a metastatic carcinoma. Clinical follow up with surgical biopsy was recommended. Surgical biopsy demonstrated histological and cytological features of papillary thyroid carcinoma including prominent papillae, nuclear overlapping, grooves, and intranuclear pseudoinclusions. Thus, a diagnosis of metastatic papillary thyroid carcinoma was rendered. Though skull metastasis of thyroid carcinoma is rare, it should be considered in the differential diagnosis when a skull mass lesion is encountered. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.
Clear‐cell hidradenoma in a child: A diagnostic dilemma for the cytopathologist
Authors: Gupta Ruchika , Singh Sompal , Gupta Kusum , Kudesia Madhur
Published: May 2009

Primary cutaneous tumors are infrequently subjected to fine needle aspiration cytology. As a result, the cytological reports of skin adnexal tumors like hidradenoma are scarce in the available literature.

A young boy with a painless nodule on forehead underwent fine needle aspiration. The smears showed clusters of epithelial cells containing blue cytoplasm, some of which had vacuolated cytoplasm with mild nuclear pleomorphism and occasional larger hyperchromatic nucleus. The cytological features, in conjunction with the clinical examination, suggested a skin appendageal tumor. Though nuclear pleomorphism and occasional larger nucleus posed a cytological diagnostic challenge, a diagnosis of benign appendageal tumor was suggested, considering the young age of the patient. This was later confirmed as a clear‐cell hidradenoma on excision biopsy.

The cytopathologist should consider skin appendageal tumors during evaluation of cutaneous nodules. An accurate diagnosis requires a close clinico‐pathologic correlation. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.
Mixed metaplastic carcinoma of the breast associated with pregnancy: Diagnostic dilemmas in fine‐needle aspiration cytology
Authors: Skagias Lazaros , Vasou Olympia , Michalopoulou Fani , Kondi‐Pafiti Agathi , Politi Ekaterini
Published: May 2009

Metaplastic carcinoma of the breast represents a rare entity characterized by the simultaneous presence of ductal, squamous, and/or mesenchymal components in several proportions. There are limitations in fine‐needle aspiration diagnosis due to its pathological heterogeneity. When it develops under pregnancy and lactation influence, the cytologic evaluation appears to be more difficult and accurate diagnosis often proves challenging. We describe a case of mixed metaplastic carcinoma with dominant areas of squamous metaplasia, sarcomatoid stroma with spindle cells, and a minor component of cartilaginous metaplasia. We notify our experience in diagnostic approach of this entity focusing on differential diagnosis. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.
A straightforward synthesis of 5‐ethyl‐3‐hydroxy‐4‐methyl‐2(5H)‐furanone
Authors: Tian Hong‐Yu , Zhang Hao , Sun Bao‐guo
Published: May 2009

5‐Ethyl‐3‐hydroxy‐4‐methyl‐2(5H)‐furanone has a sweet, maple, caramel odour and is an important flavour compound. It was synthesized starting from diethyl oxalate through the Grignard reaction and condensation. The effects of bases on the condensation of the intermediate, ethyl 2‐oxobutanoate, with propanal were investigated. The self‐condensation predominated when a weaker base, such as K2CO3, was used, while the yield of the desired product increased with the increasing basicity of the bases used. The self‐condensation could be suppressed completely in the presence of a stronger base, LDA or t‐BuOK, and 5‐ethyl‐3‐hydroxy‐4‐methyl‐2(5H)‐furanone was produced in about 90% separated yield in the presence of 3 eq of t‐BuOK. Copyright © 2009 John Wiley & Sons, Ltd.
High-dose ursodeoxycholic acid for the treatment of primary sclerosing cholangitis #
Authors: Lindor Keith D. , Kowdley Kris V. , Luketic Velimir A. C. , Harrison Edwyn M. , McCashland Timothy , Befeler Alex S. , Harnois Denise , Jorgensen Roberta , Petz Jan , Keach Jill , Mooney Jody , Sargeant Carol , Braaten Julie , Bernard Tamara , King Debra , Miceli Ellen , Schmoll Jeff , Hoskin Tanya , Thapa Prabin , Enders Felicity
Published: May 2009

Previous controlled trials are inconclusive regarding the efficacy of ursodeoxycholic acid (UDCA) for treating primary sclerosing cholangitis (PSC). One hundred fifty adult patients with PSC were enrolled in a long-term, randomized, double-blind controlled trial of high-dose UDCA (28-30 mg/kg/day) versus placebo. Liver biopsy and cholangiography were performed before randomization and after 5 years. The primary outcome measures were development of cirrhosis, varices, cholangiocarcinoma, liver transplantation, or death. The study was terminated after 6 years due to futility. At enrollment, the UDCA (n = 76) and placebo (n = 74) groups were similar with respect to sex, age, duration of disease, serum aspartate aminotransferase and alkaline phosphatase levels, liver histology, and Mayo risk score. During therapy, aspartate aminotransferase and alkaline phosphatase levels decreased more in the UDCA group than the placebo group (P < 0.01), but improvements in liver tests were not associated with decreased endpoints. By the end of the study, 30 patients in the UDCA group (39%) versus 19 patients in the placebo group (26%) had reached one of the pre-established clinical endpoints. After adjustment for baseline stratification characteristics, the risk of a primary endpoint was 2.3 times greater for patients on UDCA than for those on placebo (P < 0.01) and 2.1 times greater for death, transplantation, or minimal listing criteria (P = 0.038). Serious adverse events were more common in the UDCA group than the placebo group (63% versus 37% [P < 0.01]). Conclusion: Long-term, high-dose UDCA therapy is associated with improvement in serum liver tests in PSC but does not improve survival and was associated with higher rates of serious adverse events. (Hepatology 2009.)
Compensatory role of P-glycoproteins in knockout mice lacking the bile salt export pump #
Authors: Wang Renxue , Chen Huey-Ling , Liu Lin , Sheps Jonathan A. , Phillips James M. , Ling Victor
Published: May 2009

Bile salt export pump (BSEP; ATP-binding cassette, subfamily B, member 11) mutations in humans result in progressive familial intrahepatic cholestasis type 2, a fatal liver disease with greatly reduced bile flow. However in mice, Bsep knockout leads only to mild cholestasis with substantial bile flow and up-regulated P-glycoprotein genes (multidrug resistance protein 1a [Mdr1a] and Mdr1b). To determine whether P-glycoprotein is responsible for the relatively mild phenotype observed in Bsep knockout mice, we have crossed mouse strains knocked out for Bsep and the two P-glycoprotein genes and generated a triple knockout mouse. We found that a knockout of the three genes leads to a significantly more severe phenotype with impaired bile formation, jaundice, flaccid gallbladder, and increased mortality. The triple knockout mouse is the most severe genetic model of intrahepatic cholestasis yet developed. Conclusion: P-glycoprotein functions as a critical compensatory mechanism, which reduces the severity of cholestasis in Bsep knockout mice. (Hepatology 2009.)
Evaluating a nonionic surfactant as a tool to improve water availability in irrigated cotton
Authors: Sullivan D. G. , Nuti R. C. , Truman C. C.
Published: May 2009

Nonionic surfactants have been well researched in turf grass environments as a tool to ameliorate water‐repellant conditions. However, few studies have evaluated the risks and benefits of nonionic surfactant applications in row‐crop agricultural systems. The objective of this study was to evaluate the impact of a nonionic surfactant on cotton (Gossypium hirsutum L.) production on a Faceville loamy sand (fine, kaolinitic thermic Typic Kandiudult) in the coastal plain region of Georgia. The experiment consisted of two components: (1) on‐site rainfall simulation and (2) agronomic cotton field trials. Treatments were designed to test the impact of rate and frequency of surfactant applications using six combinations of application rates and timings. For the rainfall simulation component, only the control (0·0 L ha−1) and high rate (0·51 L ha−1) of surfactant applications were evaluated. During the field trial, soil water content, cotton stand counts, and yield were measured. Rainfall simulations showed that the addition of surfactant increased runoff, decreased infiltration, and promoted surface sealing. Despite the demonstrated potential for water loss, agronomic field trials showed that crop yields were not significantly different between surfactant‐treated and untreated plots. No differences in soil water content were observed between treatments at 5 and 15 cm depths; however, soil water content was significantly higher in untreated control plots at the 30 cm depth. Data demonstrate the need for clarification of soil physical/chemical properties and surfactant interactions that may lend themselves to the creation of surface seals and how these seals impact soil/water conservation and crop yield. Published in 2009 by John Wiley & Sons, Ltd.
Histone deacetylase inhibitors: Potential in cancer therapy
Authors: Marks P.A. , Xu W.‐S.
Published: May 2009

The role of histone deacetylases (HDAC) and the potential of these enzymes as therapeutic targets for cancer, neurodegenerative diseases and a number of other disorders is an area of rapidly expanding investigation. There are 18 HDACs in humans. These enzymes are not redundant in function. Eleven of the HDACs are zinc dependent, classified on the basis of homology to yeast HDACs: Class I includes HDACs 1, 2, 3, and 8; Class IIA includes HDACs 4, 5, 7, and 9; Class IIB, HDACs 6 and 10; and Class IV, HDAC 11. Class III HDACs, sirtuins 1–7, have an absolute requirement for NAD+, are not zinc dependent and generally not inhibited by compounds that inhibit zinc dependent deacetylases. In addition to histones, HDACs have many nonhistone protein substrates which have a role in regulation of gene expression, cell proliferation, cell migration, cell death, and angiogenesis. HDAC inhibitors (HDACi) have been discovered of different chemical structure. HDACi cause accumulation of acetylated forms of proteins which can alter their structure and function. HDACi can induce different phenotypes in various transformed cells, including growth arrest, apoptosis, reactive oxygen species facilitated cell death and mitotic cell death. Normal cells are relatively resistant to HDACi induced cell death. Several HDACi are in various stages of development, including clinical trials as monotherapy and in combination with other anti‐cancer drugs and radiation. The first HDACi approved by the FDA for cancer therapy is suberoylanilide hydroxamic acid (SAHA, vorinostat, Zolinza), approved for treatment of cutaneous T‐cell lymphoma. J. Cell. Biochem. 107: 600–608, 2009. © 2009 Wiley‐Liss, Inc.
Linking chronic tryptophan deficiency with impaired bone metabolism and reduced bone accrual in growing rats
Authors: Sibilia Valeria , Pagani Francesca , Lattuada Norma , Greco Antonella , Guidobono Francesca
Published: May 2009

There is increasing evidence that serotonin may regulate bone metabolism. However, its role remains to be clarified. Serotonin seems to be either beneficial or detrimental for bone tissues depending on the pharmacological manipulation used. In this study we evaluated the impact of a reduction of serotonergic stores induced by chronic tryptophan (TRP) depletion on various bone parameters in growing rats. For this purpose rats received a TRP‐free diet for 60 days. Bone mass, mineral content and density were measured by DXA and by pQCT in the appendicular skeleton. Bone metabolic markers included urinary deoxypyridinoline and serum osteocalcin measurements. IGF‐I levels were also evaluated. In TRP‐free diet rats, we found a decrease in body weight, a delayed femoral bone growth and bone mineral content as measured by DXA. pQCT analysis showed that these effects were related to a reduction of both cortical and trabecular bone and are associated with a reduction of bone strength. These effects are due to a negative shift in the balance between bone formation and resorption with a significant decrease in bone formation as evidenced by a reduction both in osteocalcin and IGF‐I levels. The present data extend our overall knowledge on the participation of serotonin in the regulation of growing bone and could be of interest in studying the impairment of bone growth in depressed subjects under particular condition of rapid bone accrual such as childhood and adolescence. J. Cell. Biochem. 107: 890–898, 2009. © 2009 Wiley‐Liss, Inc.
Reactive oxygen species‐induced cell death of rat primary astrocytes through mitochondria‐mediated mechanism
Authors: Wang Chia‐Chun , Fang Kuan‐Min , Yang Chung‐Shi , Tzeng Shun‐Fen
Published: May 2009

Astrocytes, the most abundant glial cell population in the central nervous system (CNS), play physiological roles in neuronal activities. Oxidative insult induced by the injury to the CNS causes neural cell death through extrinsic and intrinsic pathways. This study reports that reactive oxygen species (ROS) generated by exposure to the strong oxidizing agent, hexavalent chromium (Cr(VI)) as a chemical‐induced oxidative stress model, caused astrocytes to undergo an apoptosis‐like cell death through a caspase‐3‐independent mechanism. Although activating protein‐1 (AP‐1) and NF‐κB were activated in Cr(VI)‐primed astrocytes, the inhibition of their activity failed to increase astrocytic cell survival. The results further indicated that the reduction in mitochondrial membrane potential (MMP) was accompanied by an increase in the levels of ROS in Cr(VI)‐primed astrocytes. Moreover, pretreatment of astrocytes withN‐acetylcysteine (NAC), the potent ROS scavenger, attenuated ROS production and MMP loss in Cr(VI)‐primed astrocytes, and significantly increased the survival of astrocytes, implying that the elevated ROS disrupted the mitochondrial function to result in the reduction of astrocytic cell viability. In addition, the nuclear expression of apoptosis‐inducing factor (AIF) and endonuclease G (EndoG) was observed in Cr(VI)‐primed astrocytes. Taken together, evidence shows that astrocytic cell death occurs by ROS‐induced oxidative insult through a caspase‐3‐independent apoptotic mechanism involving the loss of MMP and an increase in the nuclear levels of mitochondrial pro‐apoptosis proteins (AIF/EndoG). This mitochondria‐mediated but caspase‐3‐independent apoptotic pathway may be involved in oxidative stress‐induced astrocytic cell death in the injured CNS. J. Cell. Biochem. 107: 933–943, 2009. © 2009 Wiley‐Liss, Inc.
Identification and characterization of an Nrf2‐mediated ARE upstream of the rat glutamate cysteine ligase catalytic subunit gene (GCLC)
Authors: Li Muyao , Chiu Jen‐Fu , Kelsen Anne , Lu Shelly C. , Fukagawa Naomi K.
Published: May 2009

The antioxidant response element (ARE) is an essential component of upstream regulatory sequences present on genes for most phase II detoxification enzymes, including the glutamate cysteine ligase catalytic subunit (GCLC). NF‐E2‐related factor 2 (Nrf2) is a principal transcription factor that binds to the ARE and plays a key role in cellular responses to stress via the Keap1‐Nrf2‐ARE pathway. However, the ARE that mediates human GCLC gene expression has not been found in the rat. Thus, how the ARE‐mediated Keap1‐Nrf2‐ARE pathway regulates glutathione homeostasis in the rat remains a puzzle. We have identified a putative ARE sequence ∼4 kb upstream in the rat GCLC. We further defined the rat GCLC‐ARE in the category with the most ARE characters, that is, this rat GCLC‐ARE is a sequence‐specific site that significantly enhances promoter activity in reporter genes. The rat GCLC‐ARE is an Nrf2‐mediated element to which binding has been demonstrated in nuclear extracts and induced by tert‐butylhydroquinone. Given the central role that rat models play in toxicology and pathology, this first discovery of the rat GCLC‐ARE enhancer similar to that found in the human gene has broad implications for the study of antioxidant defenses and their regulation in a number of different fields. J. Cell. Biochem. 107: 944–954, 2009. © 2009 Wiley‐Liss, Inc.
Trends in daily precipitation on the northeastern Iberian Peninsula, 1955–2006
Authors: López‐Moreno J. I. , Vicente‐Serrano S. M. , Angulo‐Martínez M. , Beguería S. , Kenawy A.
Published: May 2009

The temporal evolution of nine daily precipitation indices over the northeastern Iberian Peninsula was analysed for the period 1955–2006, using data from 217 observatories. Cross‐tabulation analysis enabled detection of statistically significant overlap among spatial distributions of trends in the study area. There was a general decrease in annual precipitation at most observatories, a decrease in the number of rainy days and precipitation intensity and an increase in the duration of dry spells. The frequency and contribution to annual precipitation of moderate and heavy rainfall events did not change at most observatories, or showed a decreasing trend in these events. There was very large spatial and seasonal variability, with implications for water management and risk assessment in the region. The decrease in precipitation was very marked in headwaters during winter and spring, potentially affecting reservoir management in the region. Heavy rainfall events generally decreased in the west of the region in winter, and in the east of the region in autumn, when these areas are more exposed to hazards related to extreme rainfall. Large differences in the sign and magnitude of trends occurred over very short distances, suggesting the need for dense networks of observatories to ensure reliable and robust detection of regional trends. Copyright © 2009 Royal Meteorological Society
Mycotoxins in fuel ethanol co‐products derived from maize: a mass balance for deoxynivalenol
Authors: Schaafsma Arthur W , Limay‐Rios Victor , Paul Diane E , Miller J David
Published: May 2009

BACKGROUND: Three matrices—corn (maize) meal, distiller's dried grains with solubles (DDGS) and condensed distiller's solubles (CDS)—were sampled in sequence from a continuous dry‐milling process plant for the determination of mass balance of deoxynivalenol (DON). Four commercially available enzyme‐linked immunosorbent assay (ELISA) kits were evaluated for their ability to measure the presence of DON. Liquid chromatography/tandem mass spectrometry (LC/MS/MS) was used as standard method to detect DON and other Fusarium toxins.

RESULTS: The concentrations of DON in DDGS and especially CDS were overestimated or underestimated by ELISA. However, for both matrices, all ELISA methods were not significantly different in their mean results from the LC/MS/MS standard, although the variability in results was much higher. DON concentrations in the CDS and the final DDGS co‐product were significantly higher (P ≤ 0.01) than in the starting material (corn grain). Toxin concentration increased by a factor of 3 on a dry weight basis in DDGS compared with the starting corn and by a factor of 4 in CDS. Mean concentration of DON in CDS was four times higher (7.11 mg kg−1) than in corn grains (1.80 mg kg−1) and 1.4 times higher than in DDGS (5.24 mg kg−1). Mass balance calculations showed that CDS was the main source of contamination of DON, comprising ca 70% of the toxin found in the final product (DDGS). Most DON (87%) was accounted for by this analysis.

CONCLUSION: Concentrations in the grain corn entering ethanol plants should be close to the dietary values recommended for swine in Canada and the USA for DON (1 mg kg−1). Small amounts of acetyldeoxynivalenol and DON glucoside were also found in the three matrices along with a small amount of zearalenone. Unlike the situation for DON, the DON glucoside was not concentrated into DDGS and CDS, indicating that it was hydrolysed during the fermentation process. Copyright © 2009 Society of Chemical Industry
Perioperative immunonutrition in head and neck cancer
Authors: Sorensen LTC Douglas , McCarthy Mary , Baumgartner MAJ Brian , Demars CPT Sean
Published: May 2009

Objectives/Hypothesis:

Immune‐modulating nutrition (IMN) support before and after surgery has the potential to promote host defense, antitumor activities, and wound healing. The purpose of this study was to examine the nutritional, immunologic, and wound healing outcomes in patients receiving IMN versus standard formula.

Study Design:

A prospective, blinded, randomized design was used for this study. Fifteen patients with head and neck squamous cell carcinoma received either an IMN formula (treatment group) or a standard stress formula (relative comparison group [RCG]) for a period of 7 days pre‐ and postoperatively.

Methods:

Albumin and prealbumin were measured at baseline, day of surgery (DOS), and postoperative day (POD) 1, 4, and 8. Immunologic outcomes included C‐reactive protein and total lymphocyte count with lymphocyte subset counts (CD3, CD4, CD8, CD4:8 ratio, CD19, CD56) at baseline, DOS, POD1, 4, and 8. Cell‐mediated immunity was evaluated by delayed‐type hypersensitivity. Wound healing was assessed using the ASEPSIS tool.

Results:

CD3+ and CD4+ T cells demonstrated a significant difference between groups on POD 1 (P = .03 for both) and CD56 NK cells on POD 8 (P = .04). In general, wounds healed without complications except for tracheoesophageal fistula development in two patients in the RCG.

Conclusions:

A trend toward less immune suppression in patients receiving IMN is supported in this study. Laryngoscope, 2009
Unsaturated PA X,20 from Renewable Resources via Metathesis and Catalytic Amidation
Authors: Mutlu Hatice , Meier Michael A. R.
Published: May 2009

The synthesis of unsaturated polyamides that can be obtained from plant oil derivatives via two different approaches is described. First, long chain aliphatic α,ω‐dienes with two symmetrically spaced amide segments were polymerized via ADMET polymerization. Secondly, dimethyl(E)‐icos‐10‐enedioate, a bio‐based unsaturated monomer that was obtained via metathesis, was polymerized with different aliphatic diamines using strong organic bases, such as TBD, as catalysts. Both reaction pathways led to unsaturated PA X,20 and the two different routes were investigated, optimized and compared. Moreover, the polymers were characterized by 1H NMR analysis and SEC, and the properties of the resulting polyamides were investigated by DSC and TGA.

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Automated Layer‐by‐Layer Deposition of Polyelectrolytes in Flow Mode
Authors: Ivanov Svetlozar , Kurniawan Fredy , Tsakova Vessela , Mirsky Vladimir M.
Published: May 2009

Multilayer structures of conducting polymers were fabricated by a simply automated approach in flow mode. Polyaniline and poly(styrene sulfonate) were used as a model system, allowing a fast electrochemical and spectroscopic determination of the amount of deposited material. The technology was applied for layer‐by‐layer deposition of up to 100 bilayers. The results demonstrate a well reproducible and almost constant amount of the adsorbed polymer at each deposition cycle. The method can be applied for deposition of other conducting or non‐conducting polymers, biological macromolecules and composites of polyelectrolytes and nanoparticles.

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Diallyl trisulfide‐induced apoptosis in human cancer cells is linked to checkpoint kinase 1‐mediated mitotic arrest
Authors: Xiao Dong , Zeng Yan , Singh Shivendra V.
Published: May 2009

Growth suppressive effect of diallyl trisulfide (DATS), a promising cancer chemopreventive constituent of garlic, against cultured human cancer cells correlates with checkpoint kinase 1 (Chk1)‐mediated mitotic arrest, but the fate of the cells arrested in mitosis remains elusive. Using LNCaP and HCT‐116 human cancer cells as a model, we now demonstrate that the Chk1‐mediated mitotic arrest resulting from DATS exposure leads to apoptosis. The DATS exposure resulted in G2 phase and mitotic arrest in both LNCaP and HCT‐116 cell lines. The G2 arrest was accompanied by downregulation of cyclin‐dependent kinase 1 (Cdk1), cell division cycle (Cdc) 25B, and Cdc25C leading to Tyr15 phosphorylation of Cdk1 (inactivation). The DATS‐mediated mitotic arrest correlated with inactivation of anaphase‐promoting complex/cyclosome as evidenced by accumulation of its substrates cyclinB1 and securin. The DATS treatment increased activating phosphorylation of Chk1 (Ser317) and transient transfection with Chk1‐targeted siRNA conferred significant protection against DATS‐induced mitotic arrest in both cell lines. The Chk1 protein knockdown also afforded partial yet statistically significant protection against apoptotic DNA fragmentation and caspase‐3 activation resulting from DATS exposure in both LNCaP and HCT‐116 cells. Even though DATS treatment resulted in stabilization and Ser15 phosphorylation of p53, the knockdown of p53 protein failed to rescue DATS‐induced mitotic arrest. In conclusion, the results of the present study indicate that Chk1 dependence of DATS‐induced mitotic arrest in human cancer cells is not influenced by the p53 status and cells arrested in mitosis upon DATS exposure are driven to apoptotic DNA fragmentation. © 2009 Wiley‐Liss, Inc.
Pediatric acute lymphoblastic leukemia complicated by secondary hemophagocytic lymphohistiocytosis
Authors: Devecioglu Omer , Anak Sema , Atay Didem , Aktan Pinar , Devecioglu Esra , Ozalp Beril , Saribeyoglu Ebru
Published: May 2009

Hemophagocytic lymphohistiocytosis (HLH) may be familial or secondary to infections, malignancies, metabolic disorders. Infectious causes are mostly viral and EBV is the mostly frequently seen etiologic agent. In this case, we report a child with acute lymphoblastic leukemia (ALL), who had three episodes of secondary HLH, possibly due to two different viral etiologies, namely CMV and RSV together with her malignancy, during her induction‐consolidation treatment. Pediatr Blood Cancer 2009;53:491–492. © 2009 Wiley‐Liss, Inc.
Post cardiac transplantation lymphoproliferative disorder presenting as t(8;14) Burkitt leukaemia/lymphoma treated with low intensity chemotherapy and rituximab
Authors: Windebank Kevin , Walwyn Tom , Kirk Richard , Parry Gareth , Hasan Asif , Bown Nick , Wilkins Bridget
Published: May 2009

Background

Post‐transplant lymphoproliferative disorder (PTLD) occasionally presents as Burkitt lymphoma/L3 leukaemia (BLL).

Procedure

We reviewed records of cases of PTLD post‐cardiac transplantation (1990–2007) occurring in our unit.

Results

There were 15 episodes in 13 patients including four cases of EBV‐driven Burkitt‐type disease with t(8;14) translocations presenting with advanced stage disease. The first case was treated with a variety of low dose chemotherapy combinations. Despite problems during therapy he obtained complete remission, but died from complications of pre‐existing cardiac allograft vasculopathy 7 months later. The subsequent three cases were treated with a UKCCSG low stage lymphoma protocol, NHL 9001 and Rituximab. They remain in complete remission.

Conclusions

In the context of PTLD the prognostic significance of advanced stage EBV‐driven BLL with the t(8;14) translocation may be different to that in immunocompetent children. Pediatr Blood Cancer 2009;53:392–396. © 2009 Wiley‐Liss, Inc.
The use of elastic compression stockings for post‐thrombotic syndrome in a child
Authors: Biss Tina T. , Kahr Walter H.A. , Brandão Leonardo R. , Chan Anthony K.C. , Thomas Karen E. , Williams Suzan
Published: May 2009

Post‐thrombotic syndrome (PTS) is a potential complication following deep vein thrombosis (DVT) in children. Guidelines for management of PTS in children are non‐existent. The absence of guidelines may limit the use of elastic compression stockings (ECS), offered for prevention and treatment of PTS in adults. We report the case of a 6‐year‐old, who developed PTS following a presumed line‐related lower limb DVT, with dramatic improvement in functional status with ECS use. The presented case highlights the subtle nature of symptoms, potential benefits and limitations of ECS use for PTS, and current lack of evidence in children. Pediatr Blood Cancer 2009;53:462–463. © 2009 Wiley‐Liss, Inc.
The thermal regime of permafrost and its susceptibility to degradation in upland terrain near Inuvik, N.W.T.
Authors: Burn C. R. , Mackay J. R. , Kokelj S. V.
Published: May 2009

Mean near‐surface ground temperatures in upland terrain near Inuvik range between −4°C and −1.2°C and the thickness of permafrost is about 90 m. The warm permafrost is due to the relatively deep snow cover that accumulates in the open‐canopy forest. Changes in surface conditions may lead to permafrost degradation in this environment, as is evident from elevated ground temperatures beneath disturbed surfaces in a gravel pit, in terrain burned by forest fire and where the snow depth has been increased by fencing. The values for mean annual ground temperature near Inuvik are lower end‐members of the distribution of ground temperatures in the boreal forests of northwest Canada. The range in the mean temperature of near‐surface permafrost throughout this 1200‐km wide belt (from 0°C to about −4°C) is comparable to the range over 100 km northwards from Inuvik across the treeline (from about −4°C to −8°C). Copyright © 2009 John Wiley & Sons, Ltd. and Her Majesty the Queen in right of Canada.
Identification of neutralizing conformational epitopes on the human papillomavirus type 31 major capsid protein and functional implications
Authors: Fleury Maxime J. J. , Touzé Antoine , Maurel Marie‐Christine , Moreau Thierry , Coursaget Pierre
Published: May 2009

The aim of this study was to characterize the conformational neutralizing epitopes of the major capsid protein of human papillomavirus type 31. Analysis of the epitopes was performed by competitive epitope mapping using 15 anti‐HPV31 and by reactivity analysis using a HPV31 mutant with an insertion of a seven‐amino acid motif within the FG loop of the capsid protein. Fine mapping of neutralizing conformational epitopes on HPV L1 was analyzed by a new approach using a system displaying a combinatorial library of constrained peptides exposed on E. coli flagella. The findings demonstrate that the HPV31 FG loop is dense in neutralizing epitopes and suggest that HPV31 MAbs bind to overlapping but distinct epitopes on the central part of the FG loop, in agreement with the exposure of the FG loop on the surface of HPV VLPs, and thus confirming that neutralizing antibodies are mainly located on the tip of capsomeres. In addition, we identified a crossreacting and partially crossneutralizing conformational epitope on the relatively well conserved N‐terminal part of the FG loop. Moreover, our findings support the hypothesis that there is no correlation between neutralization and the ability of MAbs to inhibit VLP binding to heparan sulfate, and confirm that the blocking of virus attachment to the extracellular matrix is an important mechanism of neutralization.
Alanine substitutions of noncysteine residues in the cysteine‐stabilized αβ motif
Authors: Yang Ying‐Fang , Cheng Kuo‐Chang , Tsai Ping‐Hsing , Liu Chung‐Cheng , Lee Tian‐Ren , Ping‐Chiang Lyu
Published: May 2009

The protein scaffold is a peptide framework with a high tolerance of residue modifications. The cysteine‐stabilized αβ motif (CSαβ) consists of an α‐helix and an antiparallel triple‐stranded β‐sheet connected by two disulfide bridges. Proteins containing this motif share low sequence identity but high structural similarity and has been suggested as a good scaffold for protein engineering. The Vigna radiate defensin 1 (VrD1), a plant defensin, serves here as a model protein to probe the amino acid tolerance of CSαβ motif. A systematic alanine substitution is performed on the VrD1. The key residues governing the inhibitory function and structure stability are monitored. Thirty‐two of 46 residue positions of VrD1 are altered by site‐directed mutagenesis techniques. The circular dichroism spectrum, intrinsic fluorescence spectrum, and chemical denaturation are used to analyze the conformation and structural stability of proteins. The secondary structures were highly tolerant to the amino acid substitutions; however, the protein stabilities were varied for each mutant. Many mutants, although they maintained their conformations, altered their inhibitory function significantly. In this study, we reported the first alanine scan on the plant defensin containing the CSαβ motif. The information is valuable to the scaffold with the CSαβ motif and protein engineering.
Persistence, metabolism and safety evaluation of thiamethoxam in tomato crop
Authors: Karmakar Rajib , Kulshrestha Gita
Published: May 2009

BACKGROUND: Thiamethoxam, a neonicotinoid insecticide, has been widely accepted for use in various crops, including vegetables, owing to its high efficacy against various chewing and sucking insect pests. In this particular study, the authors examined the residue dynamics of this insecticide in tomato and soil and calculated a safety index for this insecticide in an Indian context.

RESULTS: In tomato fruits, the insecticide dissipated from 82 to 87% in 10 days with a half‐life of 4 days, whereas dissipation in soil, under tomato crop, varied between 72 and 75% in 15 days with a half‐life of 9 days. Total residues reached below detectable level in 15 days in tomato fruits and 20 days in soil. Maximum damage (30%) was found in control plots, as opposed to 8–10% of fruit damage in treated plots. One degradation product was detected on the tomato fruit surface, and three metabolites were identified in tomato fruits by the LC‐MS technique. The metabolites have been reported for the first time in tomato fruits.

CONCLUSION: Thiamethoxam at normal and double the recommended use rate effectively controlled aphids, whiteflies and Helicoverpa, as the insect population decreased to a minimum within 10 days of spraying in comparison with the control. There was no significant difference between the two rates of application, and both thiamethoxam treatments significantly increased tomato fruit yield compared with the untreated control. A maximum residue limit (MRL) of 0.05 mg kg−1 for tomato has been proposed, with a corresponding preharvest interval (PHI) of 8 days. These parallel advances in toxicology and analytical chemistry have strengthened the observations that thiamethoxam can be used safely and efficiently in crop protection programmes. Copyright © 2009 Society of Chemical Industry