bluuebunny/crossref_metadata_2025 huggingface dataset:
Moisture controls on carbon dioxide dynamics of peat‐Sphagnum monoliths
Authors: Strack M. , Price J. S.
Published: January 2009

Sphagnum moss is the major peat‐forming vegetation component in boreal peatlands. The relationship between Sphagnum productivity and moss moisture content has been documented; however, the link between moss moisture content and conditions in the underlying peat column is less clear. We conducted a pilot study in which we monitored volumetric moisture content with depth and gravimetric water content of Sphagnum capitula and CO2 exchange for two peat monoliths with intact moss layer dominated by Sphagnum fuscum and S. magellanicum. Measurements were made under drying conditions and rewetting from below and following simulated precipitation events. Capitulum moisture content was related to water table position but varied between species. Both capitulum moisture content and water table position could be used to explain net CO2 exchange and respiration during drying and rewetting from below, although hysteresis was apparent where respiration was lower on rewetting than drying for the same water table position. Precipitation complicated these relationships because small events (<5 mm) rewetted the upper few centimeters of moss resulting in a change in capitulum moisture content equivalent to a rise in water table position of ∼20 cm. This change in capitulum moisture content resulted in substantial shifts in both photosynthesis and respiration rates without affecting water table position or subsurface volumetric water contents as shallow as 5 cm below the surface. While these small events will be difficult to measure in the field, this study suggests they are essential to effectively track or model Sphagnum productivity because they may contribute significantly to seasonal carbon balance. Copyright © 2009 John Wiley & Sons, Ltd.
Linking water sources with foliar nutrient status in upland plant communities in the Everglades National Park, USA
Authors: Saha Amartya K. , Lobo O'Reilly Sternberg Leonel da Silviera , Miralles‐Wilhelm Fernando
Published: January 2009

Plant communities within an ecosystem can vary in water source usage and nutrient availabilities, thus permitting community coexistence and diversity. We investigated the differences in water source utilization in two ecologically important upland plant communities: tropical hardwood hammocks and pine rocklands in the predominantly flooded Everglades ecosystem. We then linked these differences with their foliar nutrient levels and photosynthetic performance as measured by δ13C abundance. Based on a comparison of δ18O of plant stem waters with those of potential water sources (nutrient‐poor groundwater and nutrient‐rich water in organic litter referred to as soilwater), we observed that during the wet season hammock plants relied on soilwater while in the dry season they relied on groundwater. A similar seasonal shift was observed in pineland plants, however, groundwater constituted the major part of water uptake throughout the year except for late wet season. Consistent with the nutrient concentration of different water sources used in the two communities, hammocks had a greater annual mean foliar nitrogen and phosphorus concentration at the community level over pinelands as well as a higher leaf area index. High foliar N concentration in hammock plants was associated with eventual stomatal limitation of photosynthesis. Hammock species being intolerant of flooded soils are restricted to water uptake in the shallow unsaturated soil layer in the wet season, yet access the lowered groundwater table in the dry season. This dependence on a relatively narrow annual range of water table levels should be considered in South Florida water management and Everglades restoration. Copyright © 2009 John Wiley & Sons, Ltd.
Catalytic Asymmetric Oxidation of Heteroaromatic Sulfides with tert‐Butyl Hydroperoxide Catalyzed by a Titanium Complex with a New Chiral 1,2‐Diphenylethane‐1,2‐diol Ligand
Authors: Jiang Biao , Zhao Xiao‐Long , Dong Jia‐Jia , Wang Wan‐Jun
Published: January 2009

Heteroaromatic sulfoxides, especially 1H‐benzimidazolylpyridinylmethyl sulfoxides, usually used as the blockbuster gastric proton pump inhibitors (PPIs), have been prepared highly enantioselectivily by catalytic asymmetric oxidation of sulfides attached to nitrogen‐containing heterocyles with tert‐butyl hydroperoxide in the presence of a chiral titanium complex, formed in situ from Ti(iPrO)4, chiral 1,2‐diphenylethane‐1,2‐diol 3c and water. The chiral sufoxides were obtained in high yield (97 %) with excellent enantiomeric excess (up to 98 %). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Nanocomposite Films Obtained by Electrochemical Codeposition of Conducting Polymers and Carbon Nanotubes
Authors: Brânzoi Viorel , Pilan Luisa , Brânzoi Florina
Published: January 2009

The electrochemical growth of carbon nanotubes (CNTs) – conducting polymer composites offers the ability to produce three‐dimensional nanostructured films that combine the redox pseudo‐capacitive charge storage mechanism of conducting polymers with the high surface area and conductivity of CNTs [1–3]. In this paper we report the electropolymerization and characterization of polypyrrole films (PPy) doped with poly (m‐aminobenzenesulfonic acid) (PABS) functionalized single‐walled carbon nanotubes (SWCNTs) (PPy/CNTs). The negatively charged CNTs served as anionic dopant during the electropolymerization to synthesize PPy/CNTs composite films. Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and scanning electron microscopy (SEM) were used to investigate the electrochemical properties of the composite films.
Caffeic acid phenethyl ester decreases cholangiocarcinoma growth by inhibition of NF‐κB and induction of apoptosis
Authors: Onori Paolo , DeMorrow Sharon , Gaudio Eugenio , Franchitto Antonio , Mancinelli Romina , Venter Julie , Kopriva Shelley , Ueno Yoshiyuki , Alvaro Domenico , Savage Jennifer , Alpini Gianfranco , Francis Heather
Published: January 2009

Caffeic acid phenethyl ester (CAPE) inhibits the growth of tumor cells and is a known inhibitor of nuclear factor kappa beta (NF‐κB), which is constitutively active in cholangiocarcinoma (CCH) cells. We evaluated the effects of CAPE on CCH growth bothin vitroandin vivo.Inhibition of NF‐κB DNA‐binding activity was confirmed in nuclear extracts treated with CAPE at 50, 40 and 20 μM. CAPE decreases the expression of NF‐κB1 (p50) and RelA (p65). CAPE decreased the growth of a number of CCH cells but not normal cholangiocytes. Cell cycle decrease was seen by a decrease in PCNA protein expression and the number of BrdU‐positive cells treated with CAPE at 20 μM compared to vehicle. Inhibition of growth and increased cell cycle arrest of Mz‐ChA‐1 cells by CAPE were coupled with increased apoptosis. Bax expression was increased, whereas Bcl‐2 was decreased in cells treated with CAPE compared to vehicle.In vivostudies were performed in BALB/c nude (nu/nu) mice implanted subcutaneously with Mz‐ChA‐1 cells and treated with daily IP injections of DMSO or CAPE (10 mg/kg body weight in DMSO) for 77 days. Tumor growth was decreased and tumor latency was increased 2‐fold in CAPE compared to vehicle‐treated nude mice. In tumor samples, decreased CCH growth by CAPE was coupled with increased apoptosis. CAPE bothin vivoandin vitrodecreases the growth of CCH cells by increasing apoptosis. These results demonstrate that CAPE might be an important therapeutic tool in the treatment of CCH. © 2009 UICC
Increased levels of copper efflux transporter ATP7B are associated with poor outcome in colorectal cancer patients receiving oxaliplatin‐based chemotherapy
Authors: Martinez‐Balibrea Eva , Martínez‐Cardús Anna , Musulén Eva , Ginés Alba , Manzano José Luis , Aranda Enrique , Plasencia Carmen , Neamati Nouri , Abad Albert
Published: January 2009

Recently, the copper efflux transporters ATP7B and ATP7A have been implicated in the transport of and resistance to platinum drugs in breast and ovarian cancers. Because of the extensive use of oxaliplatin in colorectal cancer (CRC), we examined the expression of both transporters in tumors from CRC patients treated with oxaliplatin/5FU and sought to determine whether their expression can predict clinical outcome in these patients. ATP7B and ATP7A levels were determined by quantitative real‐time PCR in 50 primary tumors of previously untreated patients with advanced colorectal adenocarcinoma who were subsequently treated with oxaliplatin/5FU. Additionally, ATP7B protein expression was assessed by immunohistochemical staining using a tissue microarray. Patients with the lowest mRNA expression levels of ATP7B had a significantly longer time to progression (TTP) (p = 0.0009) than patients with the highest levels (12.14 months vs. 6.43 months) who also had an increased risk of progression (HR = 3.56; 95% CI, 1.6–7.9; p = 0.002). Furthermore, patients with low levels of both protein and mRNA of ATP7B derived the maximum benefit from oxaliplatin/5FU with the longest TTP as compared with patients with high levels of ATP7B protein and mRNA (14.64 months vs. 4.63 months, respectively, p = 0.01) and showed a nonsignificant trend toward a lower response rate (37.5% and 75%, respectively). In conclusion, ATP7B mRNA and protein expression in colorectal tumors is associated with clinical outcome to oxaliplatin/5FU. Prospective studies are required to evaluate the role of this marker in tailoring chemotherapy. © 2009 UICC
TMF/ARA160 downregulates proangiogenic genes and attenuates the progression of PC3 xenografts
Authors: Abrham Galya , Volpe Marina , Shpungin Sally , Nir Uri
Published: January 2009

TMF/ARA160 is a Golgi‐associated protein whose level is downregulated in solid tumors. TMF changes its subcellular localization on exposure of cells to stress cues, thereby, directing proteins, such as the key transcription factor, Stat3, to proteasomal degradation. Here, we show that enforced ectopic expression of HA‐TMF in PC3 prostate carcinoma cells, which do not express Stat3, significantly attenuated the development and growth of xenograft tumors elicited by these cells in athymic mice. Immunohistochemical analysis revealed impaired angiogenesis and accelerated onset of apoptosis in the HA‐TMF‐expressing tumors. RNA expression profiling revealed the downregulation of several proangiogenic genes in HA‐TMF‐expressing xenografts. Among these were the interleukin‐8 and interleukin‐1β genes, whose expression is controlled by nuclear factor‐kB. The level of the nuclear factor‐kB component, p65/RelA, was decreased in HA‐TMF‐expressing xenografts, and TMF was found to direct the ubiquitination and proteasomal degradation of p65/RelA in metabolically stressed PC3 clones. Taken together, our findings indicate that TMF/ARA160 is a regulator of key transcription factors under metabolic constraints, thereby affecting angiogenesis and progression of solid tumors, which are subjected to metabolic stress. © 2009 UICC
High serum interleukin‐6 level predicts future hepatocellular carcinoma development in patients with chronic hepatitis B
Authors: Wong Vincent Wai‐Sun , Yu Jun , Cheng Alfred Sze‐Lok , Wong Grace Lai‐Hung , Chan Hoi‐Yun , Chu Eagle Siu‐Hong , Ng Enders Kai‐On , Chan Francis Ka‐Leung , Sung Joseph Jao‐Yao , Chan Henry Lik‐Yuen
Published: January 2009

Increased interleukin‐6 (IL‐6) production is implicated in the pathogenesis of hepatocellular carcinoma (HCC) in animal models. Although previous studies showed that HCC patients had higher serum IL‐6 level at the time of diagnosis, it is unclear if the cytokine contributes to the development of HCC or is just a reaction to cancer. To address this question, we performed a nested case‐control study. Consecutive chronic hepatitis B patients were recruited from 1997 to 2000 and followed till 2008. Profiling of 27 cytokines, chemokines and growth factors was performed at baseline, date of peak alanine aminotransferase (ALT) level and the last visit. Thirty‐seven patients developed HCC at a median follow‐up of 62 months (interquartile range: 41–110). Serum IL‐6 was higher in patients with HCC than controls both during peak ALT and at the last visit (both p = 0.02). Patients with IL‐6 above 7 pg/ml during peak ALT had increased risk of HCC or death (adjusted hazard ratio 3.0; 95% confidence interval 1.2, 7.8; p = 0.02). The sensitivity, specificity, positive and negative predictive values of this cutoff to predict future HCC development were 70%, 73%, 72% and 71%, respectively. Combination of IL‐6 and AFP improved the sensitivity in diagnosing HCC or predicting future HCC development. In conclusion, high serum IL‐6 level predates the development of HCC in chronic hepatitis B patients, and has moderate accuracy in predicting future cancer. This may assist clinicians in selecting high‐risk patients for HCC surveillance program. © 2009 UICC
Nongenomic effect of estrogen on the MAPK signaling pathway and calcium influx in endometrial carcinoma cells
Authors: Zhang Lili , Li Xiaoping , Zhao Lijun , Zhang Lifang , Zhang Guo , Wang Jianliu , Wei Lihui
Published: January 2009

17β‐Estradiol (E2) is well known to interact with intracellular receptors that act as nuclear transcription factors. However, abundant evidence now indicates that E2 can also rapidly induce several nongenomic effects through signaling pathways related to cell growth, preservation, and differentiation. We studied the nongenomic effects of E2 in two human endometrial carcinoma cell lines, Ishikawa (estrogen receptor (ER) positive) and Hec‐1A (ER negative or low) by cultivating them with either E2 or its membrane‐impermeable conjugate, E2–BSA. We found that phosphorylation of Erk1/2 could be induced by either E2 or E2–BSA in Ishikawa cells. In Hec‐1A cells, only E2 was able to induce Erk1/2 phosphorylation. Although the existence of a nongenomic component to the response was indicated by the finding that it could not be completely inhibited by the ER antagonist ICI182780,and it can also be inhibited by calcium inhibitor Nifedipine partly. Phosphorylation of Akt could not be induced, either by E2 or E2–BSA, in either cell line. Both E2 and E2–BSA elicited calcium influx in Ishikawa cells. In contrast to these nongenomic effects, only E2 was able to stimulate expression of the anti‐apoptotic‐protein Bcl‐2. Taken together, these data indicate that nongenomic effects such as Erk1/2 phosphorylation and calcium influx can be initiated from the membrane in Ishikawa cell, and calcium can activate Erk1/2 phosphorylation. Except for ER, there must be other binding location of estrogen in endometrial cancer cells, and the nongenomic effects of estrogen initiated from plasma membrane by E2–BSA cannot lead to transcriptional effect of Bcl‐2 expression. J. Cell. Biochem. 106: 553–562, 2009. © 2009 Wiley‐Liss, Inc.
Adenosine triggers the nuclear translocation of protein kinase C epsilon in H9c2 cardiomyoblasts with the loss of phosphorylation at Ser729
Authors: Xu Tian‐Rui , He Guiyuan , Rumsby Martin G.
Published: January 2009

Adenosine is a major mediator of ischaemic preconditioning (IPC) and cardioprotection. The translocation and activation of protein kinase C epsilon, triggered by adenosine, are essential for these processes. We report here that H9c2 cardiomyoblasts express five PKC isoforms (α, βI, δ, ε and ζ). PKCε is predominantly associated with F‐actin fibres in unstimulated H9c2 cells but translocates to the nucleus on stimulation with adenosine. Cytosolic PKCε associated with F‐actin fibres is phosphorylated at Ser729 but nuclear PKCε lacks phosphorylation at this site. Adenosine triggers the nuclear translocation after 5 min stimulation. PKCε Ser729Ala and Ser729Glu mutants showed no translocation on adenosine stimulation suggesting both phosphorylation and serine at 729 are critical for this translocation. Among five PKC isoforms (α, βI, δ, ε and ζ) detected, PKCε is the only isoform translocating to the nucleus upon adenosine stimulation. Disruption of microtubules (MTs), but not F‐actin‐rich fibres, blocked translocation of both endogenous PKCε and overexpressed GFP‐PKCε to the nucleus. Ten proteins interacted with cytosolic PKCε; five of which are components of myofibrils. Matrin 3 and vimentin interacted with nuclear PKCε. These findings suggest that adenosine stimulates PKCε translocation to the nucleus in H9c2 cells in a mechanism involving dephosphorylation at Ser729 and MT, which should advance our understanding of the signalling pathways stimulated by adenosine in IPC and cardioprotection. J. Cell. Biochem. 106: 633–642, 2009. © 2009 Wiley‐Liss, Inc.
The nucleosomal binding protein NSBP1 is highly expressed in the placenta and modulates the expression of differentiation markers in placental Rcho‐1 cells
Authors: Shirakawa Hitoshi , Rochman Mark , Furusawa Takashi , Kuehn Michael R. , Horigome Satoru , Haketa Keiichi , Sugita Yumi , Inada Tomoyuki , Komai Michio , Bustin Michael
Published: January 2009

We report that NSBP1, a nucleosome binding protein that affects the structure of chromatin, is highly expressed in mouse placenta. In Rcho‐1 cells, which recapitulate the differentiation of trophoblast giant cells of living placenta, NSBP1 expression is linked to differentiation. Disregulation of NSBP1 protein levels, by either siRNA treatment or by overexpression, alters the expression of several members of the prolactin gene family without affecting the levels of several transcription factors involved in placental differentiation. Our studies identify NSBP1 as a nucleosome binding protein that modulates the expression of prolactin gene family members most likely by inducing changes in chromatin structure. J. Cell. Biochem. 106: 651–658, 2009. © 2009 Wiley‐Liss, Inc.
The important role of the apoptotic effects of zinc in the development of cancers
Authors: Franklin Renty B. , Costello Leslie C.
Published: January 2009

Zinc is a trace element that is essential for the normal function of cells. It is a cofactor for the structure and function of a wide range of cellular proteins including enzymes, transcription factors, and structural proteins. Recent studies have shown that zinc plays a role in the development of various cancers. Unfortunately no established common relationships of zinc with cancer development and progression have been identified. Zinc is known to have systemic effects such as regulation of the immune system as well as direct cellular effects resulting in regulation of gene expression, bioenergetics, metabolic pathways, signal transduction and cell invasion. Zinc is also reported to regulate cell proliferation and growth. In this review presentation we focus on the effects of zinc that are involved in the regulation of apoptosis in malignant cells. We selected the apoptotic effects of zinc because zinc is reported to both induce apoptosis in some cancers and to protect other cancer cells against apoptosis induced by other factors. The effects of zinc in the regulation of apoptosis appear to be cell type specific. More importantly the reported effects of zinc on cancer cells must be viewed from the perspective of the physiological regulation of zinc homeostasis. Thus one must be mindful of the experimental conditions under which zinc effects are investigated relative to the physiological and pathological conditions of cellular zinc distribution and concentrations that can exist in situ. J. Cell. Biochem. 106: 750–757, 2009. © 2009 Wiley‐Liss, Inc.
Cellular and functional analysis of four mutations located in the mitochondrial ATPase6 gene
Authors: Vazquez‐Memije Martha Elisa , Rizza Teresa , Meschini Maria Chiara , Nesti Claudia , Santorelli Filippo Maria , Carrozzo Rosalba
Published: January 2009

The smallest rotary motor of living cells, F0F1‐ATP synthase, couples proton flow—generated by the OXPHOS system—from the intermembrane space back to the matrix with the conversion of ADP to ATP. While all mutations affecting the multisubunit complexes of the OXPHOS system probably impact on the cell's output of ATP, only mutations in complex V can be considered to affect this output directly. So far, most of the F0F1‐ATP synthase variations have been detected in the mitochondrial ATPase6 gene. In this study, the four most frequent mutations in the ATPase6 gene, namely L156R, L217R, L156P, and L217P, are studied for the first time together, both in primary cells and in cybrid clones. Arginine (“R”) mutations were associated with a much more severe phenotype than Proline (“P”) mutations, in terms of both biochemical activity and growth capacity. Also, a threshold effect in both “R” mutations appeared at 50% mutation load. Different mechanisms seemed to emerge for the two “R” mutations: the F1 seemed loosely bound to the membrane in the L156R mutant, whereas the L217R mutant induced low activity of complex V, possibly the result of a reduced rate of proton flow through the A6 channel. J. Cell. Biochem. 106: 878–886, 2009. © 2009 Wiley‐Liss, Inc.
Identification and expansion of human osteosarcoma‐cancer‐stem cells by long‐term 3‐aminobenzamide treatment
Authors: Di Fiore Riccardo , Santulli Andrea , Drago Ferrante Rosa , Giuliano Michela , De Blasio Anna , Messina Concetta , Pirozzi Giuseppe , Tirino Virginia , Tesoriere Giovanni , Vento Renza
Published: January 2009

A novel cancer stem‐like cell line (3AB‐OS), expressing a number of pluripotent stem cell markers, was irreversibly selected from human osteosarcoma MG‐63 cells by long‐term treatment (100 days) with 3‐aminobenzamide (3AB). 3AB‐OS cells are a heterogeneous and stable cell population composed by three types of fibroblastoid cells, spindle‐shaped, polygonal‐shaped, and rounded‐shaped. With respect to MG‐63 cells, 3AB‐OS cells are extremely smaller, possess a much greater capacity to form spheres, a stronger self‐renewal ability and much higher levels of cell cycle markers which account for G1‐S/G2‐M phases progression. Differently from MG‐63 cells, 3AB‐OS cells can be reseeded unlimitedly without losing their proliferative potential. They show an ATP‐binding cassette transporter ABCG2‐dependent phenotype with high drug efflux capacity, and a strong positivity for CD133, marker for pluripotent stem cells, which are almost unmeasurable in MG‐63 cells. 3AB‐OS cells are much less committed to osteogenic and adipogenic differentiation than MG‐63 cells and highly express genes required for maintaining stem cell state (Oct3/4, hTERT, nucleostemin, Nanog) and for inhibiting apoptosis (HIF‐1α, FLIP‐L, Bcl‐2, XIAP, IAPs, and survivin). 3AB‐OS may be a novel tumor cell line useful for investigating the mechanisms by which stem cells enrichment may be induced in a tumor cell line. The identification of a subpopulation of cancer stem cells that drives tumorigenesis and chemoresistance in osteosarcoma may lead to prognosis and optimal therapy determination. Expression patterns of stem cell markers, especially CD133 and ABCG2, may indicate the undifferentiated state of osteosarcoma tumors, and may correlate with unfavorable prognosis in the clinical setting. J. Cell. Physiol. 219: 301–313, 2009. © 2009 Wiley‐Liss, Inc.
Ion/Molecule reactions in SiH4/H2S and GeH4/H2S mixtures
Authors: Antoniotti Paola , Operti Lorenza , Rabezzana Roberto , Turco Francesca , Vaglio Gian Angelo , Grandinetti Felice
Published: January 2009

The gas phase ion chemistry of silane/hydrogen sulfide and germane/hydrogen sulfide mixtures was studied by ion trap mass spectrometry (ITMS), in both positive and negative ionization mode. In positive ionization, formation of X/S (X = Si, Ge) mixed ions mainly takes place via reactions of silane or germane ions with H2S, through condensation followed by dehydrogenation. This is particularly evident in the system with silane. On the other side, reactions of HnS2+ ions with XH4 (X = Si, Ge) invariably lead to formation of a single XS bond. In negative ionization, a more limited number of mixed ion species is detected, but their overall abundance reaches appreciable values, especially in the SiH4/H2S system. Present results clearly indicate that ion processes play an important role in formation and growth of clusters eventually leading to deposition of amorphous solids in chemical vapor deposition (CVD) processes. Copyright © 2009 John Wiley & Sons, Ltd.
Desorption electrospray ionization mass spectrometry of DNA nucleobases: implications for a liquid film model
Authors: Qiu Bo , Luo Hai
Published: January 2009

Desorption electrospray ionization (DESI) mass spectrometry has been implemented on a commercial ion‐trap mass spectrometer and used to optimize mass spectrometric conditions for DNA nucleobases: adenine, cytosine, thymine, and guanine. Experimental parameters including spray voltage, distance between mass spectrometer inlet and the sampled spot, and nebulizing gas inlet pressure were optimized. Cluster ions including some magic number clusters of nucleobases were observed for the first time using DESI mass spectrometry. The formation of the cluster species was found to vary with the nucleobases, acidification of the spray solvent, and the deposited sample amount. All the experimental results can be explained well using a liquid film model based on the two‐step droplet pick‐up mechanism. It is further suggested that solubility of the analytes in the spray solvent is an important factor to consider for their studies by using DESI. Copyright © 2009 John Wiley & Sons, Ltd.
A longitudinal examination of the work–nonwork boundary strength construct
Authors: Hecht Tracy D. , Allen Natalie J.
Published: January 2009

Many organizations are blurring the boundaries between work and nonwork through practices such as flextime, telecommuting, and on‐site day‐cares. Such integration of work and nonwork is purported to help employees find the seemingly elusive “work‐life balance.” Scholarly investigations of this issue have increased in number, but a standard measure of work–nonwork boundary strength has yet to emerge. The purpose of this research is to explore the boundary strength construct through the process of measure validation. In Study 1, data were collected from students (N = 162) to pilot test the measure. Study 2 was a longitudinal field study in which data were collected from employees of Canadian organizations (Survey 1: N = 793; Matched data for Surveys 1 & 2: N = 205). Confirmatory factor analyses supported the hypothesized two‐factor structure of the work–nonwork boundary strength measure, confirming the importance of differentiating boundary strength at home (BSH) and boundary strength at work (BSW). Longitudinal analyses confirmed the structural invariance of the measure and revealed that boundary strengths are relatively stable over a period of 1 year. Role identification was related to boundary strength at home only. Weak boundaries, both at home and at work, were associated with high inter‐role conflict. Copyright © 2009 John Wiley & Sons, Ltd.
How changes in job demands and resources predict burnout, work engagement, and sickness absenteeism
Authors: Schaufeli Wilmar B. , Bakker Arnold B. , Van Rhenen Willem
Published: January 2009

The present longitudinal survey among 201 telecom managers supports the Job Demands‐Resources (JD‐R) model that postulates a health impairment process and a motivational process. As hypothesized, results of structural equation modeling analyses revealed that: (1) increases in job demands (i.e., overload, emotional demands, and work‐home interference) and decreases in job resources (i.e., social support, autonomy, opportunities to learn, and feedback) predict burnout, (2) increases in job resources predict work engagement, and (3) burnout (positively) and engagement (negatively) predict registered sickness duration (“involuntary” absence) and frequency (“involuntary” absence), respectively. Finally, consistent with predictions results suggest a positive gain spiral: initial work engagement predicts an increase in job resources, which, in its turn, further increases work engagement. Copyright © 2009 John Wiley & Sons, Ltd.
Validation of green‐solvent extraction combined with chromatographic chemical fingerprint to evaluate quality of Stevia rebaudiana Bertoni
Authors: Teo Chin Chye , Tan Swee Ngin , Yong Jean Wan Hong , Hew Choy Sin , Ong Eng Shi
Published: January 2009

An approach that combined green‐solvent methods of extraction with chromatographic chemical fingerprint and pattern recognition tools such as principal component analysis (PCA) was used to evaluate the quality of medicinal plants. Pressurized hot water extraction (PHWE) and microwave‐assisted extraction (MAE) were used and their extraction efficiencies to extract two bioactive compounds, namely stevioside (SV) and rebaudioside A (RA), from Stevia rebaudiana Bertoni (SB) under different cultivation conditions were compared. The proposed methods showed that SV and RA could be extracted from SB using pure water under optimized conditions. The extraction efficiency of the methods was observed to be higher or comparable to heating under reflux with water. The method precision (RSD, n = 6) was found to vary from 1.91 to 2.86% for the two different methods on different days. Compared to PHWE, MAE has higher extraction efficiency with shorter extraction time. MAE was also found to extract more chemical constituents and provide distinctive chemical fingerprints for quality control purposes. Thus, a combination of MAE with chromatographic chemical fingerprints and PCA provided a simple and rapid approach for the comparison and classification of medicinal plants from different growth conditions. Hence, the current work highlighted the importance of extraction method in chemical fingerprinting for the classification of medicinal plants from different cultivation conditions with the aid of pattern recognition tools used.
Candidate's Thesis: Laryngotracheal separation in neurologically impaired children: Long‐term results
Authors: Cook Steven P.
Published: January 2009

Objectives:

Fifty‐six consecutive neurologically impaired pediatric children underwent laryngotracheal separation (LTS) for acute recurrent and chronic aspiration in the last 18 years. The population demographics, indications for surgery, and comorbidities are reviewed. This study reports early and late complications and survivorship including admissions for pneumonia/aspiration. Diagnosis related group (DRGs) and work relative value units (wRVUs) were measured to document the potential benefits before and after LTS.

Study Design:

Retrospective review of patient charts and records in an electronic medical record during an 18 year period.

Methods:

Information was obtained by a chart review and utilization of the electronic medical record. Patient specific DRG and wRVU data on their hospitalizations and outpatient encounters at the Alfred I. duPont Hospital for Children of the Nemours Foundation and survival data were recorded. Data was analyzed using chi‐square analysis, a two‐tailedttest, and a Fisher's Exact test.

Results:

Laryngotracheal separation achieved complete control of aspiration in all the children. A significant reduction in the number of hospital admissions for pneumonias after surgery was noted. After LTS there was a reduced average number of DRGs per month (p < .001) as well as wRVUs. Transient fistula formation (11%) was the most common complication. No patient had his or her procedure reversed to date.

Conclusion:

Laryngotracheal separation is 100% effective in controlling aspiration in all of neurologically impaired children in this study, It is a valuable procedure to prolong the life of children who have intractable aspiration. After LTS, a decrease in DRGs and wRVUs reduces health care costs for these patients. Prior to LTS, all medical and surgical treatment options for aspiration should be discussed and considered, based on the extent of the child's underlying neurologic status, ability to verbally communicate, degree of upper airway obstruction, and hope of recovery of neurologic function. Laryngoscope, 2009
Utility of anti‐HSP 70, TNF‐α, ESR, antinuclear antibody, and antiphospholipid antibodies in the diagnosis and treatment of sudden sensorineural hearing loss
Authors: Süslü Nilda , Yılmaz Taner , Gürsel Bülent
Published: January 2009

Objectives:

To investigate the performance of various laboratory tests used for patients with sudden sensorineural hearing loss (SSNHL).

Study Design:

Prospective clinical trial.

Methods:

Thirty patients who presented with SSNHL and 30 healthy people with no cochleovestibular disorders were selected as study and control groups.The laboratory panel includes the following tests: anti‐HSP 70 antibody immunoassay, tumor necrosis factor‐alpha (TNF‐α), erythrocyte sedimentation rate (ESR), antinuclear antibody (ANA), and antiphospholipid antibodies. The study group was given corticosteroid therapy and separated into two groups: the corticosteroid responders and the corticosteroid nonresponders. In the follow‐up, repeat audiograms were evaluated to determine the response to treatment.

Results:

TNF‐α was found at lower titers in the study group when compared with the control group in contrast to other studies. Also, anti‐HSP 70 was not found in high titers in the study group. ANA and ESR were the two parameters that were significantly more positive in the study group compared with the control group.

Conclusions:

Because of the lack of association between a positive test and response to corticosteroid treatment, detection of the anti‐HSP 70 antibody, TNF‐α, ESR, and ANA, at present, do not offer clinically useful information in the treatment of SSNHL. Also, because of the lower titers of TNF‐α documented in patients with SSNHL, we do not recommend the use of specific TNF‐α inhibitors in SSNHL. Laryngoscope, 2009
Changing patterns of tracheotomy use in anterior skull base surgery with free tissue reconstruction
Authors: Myers Larry L. , Sumer Baran D. , Lowery Jamel E. , Truelson John M. , Leach Joseph L. , Sinard Robert J.
Published: January 2009

Objective:

To evaluate how changing patterns of tracheotomy use with free tissue reconstruction of the anterior skull base affect postoperative complications.

Design:

Retrospective comparison of clinical cohort to historic control group.

Setting:

Tertiary care medical center.

Patients:

We reviewed 201 patients with a diagnosis of malignant or locally aggressive benign neoplasms of the nasal cavity and paranasal sinuses between January 1993 and December 2006. Of these, we studied 33 consecutive patients that underwent ablative anterior skull base surgery reconstructed with free tissue transfers. We divided the study group into two cohorts: Group 1, patients treated from 1993–2000, and Group 2, patients treated from 2000–2006.

Main Outcome Measures:

Tracheotomy use and postoperative complications.

Results:

There were 16 patients in Group 1 and 17 patients in Group 2. There were 11 patients who received a tracheotomy in Group 1, and only 5 in Group 2 (P = .038). Five patients in either group experienced complications (P = 1.000). There was one case of meningitis in Group 1 and no cases in Group 2 (P = .485). There were two cases of pneumocephalus in Group 2 and none in Group 1 (P = .485) and no cases of tension pneumocephalus. Six patients in each group had recurrent disease (P = 1.000). There was no statistically significant difference in survival (P = .675).

Conclusions:

The decreased use of tracheotomy in patients undergoing free tissue transfer reconstruction of anterior skull base defects did not lead to an increase in complications. Routine use of tracheotomy in these patients is unnecessary and should be reserved for selected cases. Laryngoscope, 2009
The effect of topical amphotericin B on inflammatory markers in patients with chronic rhinosinusitis: A multicenter randomized controlled study
Authors: Ebbens Fenna A. , Georgalas Christos , Luiten Silvia , van Drunen Cornelis M. , Badia Lydia , Scadding Glenis K. , Hellings Peter W. , Jorissen Mark , Mullol Joaquim , Cardesin Alda , Bachert Claus , van Zele Thibaut P. J. , Lund Valerie J. , Fokkens W. J.
Published: January 2009

Background:

It has been suggested that an exaggerated immune response to fungi is crucial in the pathogenesis of chronic rhinosinusitis (CRS). Based on this rationale, the use of topical antifungals (amphotericin B) has been advocated. Studies on its clinical effectiveness are, however, contradictory.

Objectives:

To examine the effect of nasal antifungal treatment on secreted mediators in samples of nasal lavage fluid from patients with CRS with or without nasal polyps (NP).

Methods:

Part two of a prospective double‐blind, placebo‐controlled multicenter clinical trial investigating the effect of 13 weeks of treatment with amphotericin B or placebo on the levels of pro‐inflammatory cytokines, chemokines and growth factors (i.e., IL‐1β, IL‐1RA, IL‐2, IL‐2R, IL‐3, IL‐4, IL‐5, IL‐6, IL‐7, IL‐8, IL‐10, IL‐12 (p40/p70 subunits), IL‐13, IL‐15, IL‐17, TNF‐α, IFN‐α, IFN‐γ, G‐CSF, GM‐CSF, MIP‐1α, MIP‐1β, IP‐10, MIG, eotaxin, RANTES, MCP‐1, MCP‐2, MCP‐3, VEGF, EGF, FGF‐basic, HGF, Gro‐α) and albumin via a fluorescent enzyme immunoassay in nasal lavage specimens of CRS patients with or without NP.

Results:

Topical amphotericin B had no significant effect on the level of any of the tested pro‐inflammatory cytokines, chemokines, and growth factors in CRS nasal lavage samples. Treatment with placebo, however, increased the level of MIP‐1α and MIP‐1β, which are mediators involved in wound healing.

Conclusions:

Topical amphotericin B has no significant effect on activation markers of nasal inflammatory cells in chronic rhinosinusitis with or without nasal polyps. Laryngoscope, 2009
Antiestrogen therapy for hereditary hemorrhagic telangiectasia: A double‐blind placebo‐controlled clinical trial
Authors: Yaniv Eitan , Preis Michal , Hadar Tuvia , Shvero Jacob , Haddad Miriam
Published: January 2009

Objectives/Hypothesis:

Hereditary hemorrhagic telangiectasia (HHT) is associated with recurrent epistaxis in 90% of cases. Good response to hormone treatment has been documented, although its use remains controversial. The aim of this study was to examine the efficacy of an antiestrogenic agent, Tamoxifen, in the treatment of HHT‐associated epistaxis.

Methods:

Twenty‐five patients (11 men, 14 women; mean age 51 years) with a diagnosis of epistaxis due to HHT were randomly assigned to receive treatment with oral tamoxifen 20 mg/d or placebo for 6 months. Follow‐up consisted of physical examination and once‐monthly blood tests.

Results:

The groups were similar in age and sex distribution. Of the 21 participants who completed the trial, alleviation of the epistaxis was noted in 9 of 10 tamoxifen‐treated patients and 3 of 11 placebo‐treated patients (including 2 with only temporary improvement). The difference between the groups at the trial end point was significant for both frequency (P= .01) and severity (P= .049) of the disease. Hemoglobin concentration rose in 4 tamoxifen‐treated patients and decreased in 5 controls.

Conclusions:

Tamoxifen appears to be an effective agent for the treatment of epistaxis due to HHT. Laryngoscope, 2009
Cochlear implantation is associated with minimal anesthetic risk in the elderly
Authors: Coelho Daniel H. , Yeh Joseph , Kim Jung T. , Lalwani Anil K.
Published: January 2009

Objectives/Hypothesis:

Most elderly patients with severe to profound hearing loss are not being referred for cochlear implantation (CI), the only intervention to significantly improve hearing and quality of life in this population. Possible concern over the risks of anesthetic in the elderly may be one of the foremost concerns. The authors investigated whether advanced age is a risk factor when undergoing general anesthesia for cochlear implantation.

Study Design:

Retrospective chart review.

Methods:

A retrospective chart review was conducted at a tertiary academic referral center of 70 patients older than 70 years, who underwent CI with general anesthesia between 1984 and 2007, and for whom anesthesia records were available. Patients were divided into anesthetic risk group A (American Society of Anesthesiologist classification [ASA] I/II) and B (ASA III/IV). Intraoperative and postoperative anesthesia‐related complications were identified.

Results:

Of the 70 patients, 44 were in group A and 26 were in group B, both with a mean age of 77. Four patients, one from group A and three from group B, required intraoperative pressors for blood pressure support. There were no anesthesia‐related complications in group A, but there were three (12% of group B and 4% overall) in group B: delayed extubation, postoperative congestive heart failure, and urinary retention. There was no long‐term morbidity or mortality.

Conclusions:

General anesthesia is well tolerated by elderly patients undergoing cochlear implantation. Preexisting medical condition of the patient as defined by ASA is a better predictor of intraoperative and postoperative complication than age alone. Laryngoscope, 2009
Radiotherapy in laryngeal carcinoma: Can a panel of 13 markers predict response?
Authors: Wildeman Maarten A. M. , Gibcus Johan H. , Hauptmann Michael , Begg Adrian C. , van Velthuysen Marie Louise F. , Hoebers Frank J. , Mastik Mirjam F. , Schuuring Ed , van der Wal Jacqueline E. , van den Brekel Michiel W. M.
Published: January 2009

Objectives/Hypothesis:

To find biomarkers associated with response to radiotherapy in laryngeal cancer that can be used together with clinical parameters to improve outcome prediction.

Methods:

In this study, 26 patients irradiated for laryngeal carcinomas with a local recurrence within two years (cases) and 33 patients without recurrence (controls) were included. All pretreatment biopsies were arrayed onto a tissue array. Immunohistochemistry was performed for 13 biomarkers that were selected from the literature as potential predictors for radioresponse in head and neck (HN) cancer: Bcl‐2, Bcl‐xL, p16, p21, p27, p53, cyclin D1, HIF‐1α, CA9, COX‐2, EGFR, ki‐67, and pRB.

Results:

Univariate logistic regression models showed borderline statistically significant increased relative risks, with positivity for CA9, COX‐2, and p53. Goeman's global testing revealed an overall association between outcome and the 13 markers together with clinical variables. The most important markers were CA9 and COX‐2.

Conclusions:

In laryngeal carcinoma, hypoxia and COX‐2 overexpression provide a stronger contribution to an increased risk of local recurrence after radiotherapy compared with the well‐known candidate markers p53, Bcl‐2, and cyclin D1. However, no robust expression profile for the prediction of radioresistance was found. Laryngoscope, 2009
Frequency of a dental source for acute maxillary sinusitis
Authors: Bomeli Steven R. , Branstetter Barton F. , Ferguson Berrylin J.
Published: January 2009

Objective:

To identify radiographic features of odontogenic acute maxillary sinusitis and to determine the frequency of a causative dental infection in patients with radiographic evidence of maxillary sinus fluid.

Study Design:

Retrospective review of 101 sinus computed tomography scans with unilateral or bilateral maxillary sinus fluid.

Methods:

Each maxillary sinus was graded for extent of fluid, degree of mucosal thickening, and presence of dental pathology. Univariate chi‐square analysis was used to identify potential radiologic and demographic features predictive of sinus fluid. Multivariate logistic regression was then used to determine which features were independently predictive.

Results:

124 of the 202 maxillary sinuses (61%) had sinus fluid. Univariate analysis excluded age, gender, and prior surgery as predictive features. The multivariate analysis included the radiographic features of oroantral fistula, periapical abscess, periodontal disease, projecting tooth root, and dental caries. Of these, only oroantral fistula and the combination of periodontal disease with either a projecting tooth root or periapical abscess were identified as significant sources of maxillary sinusitis. In sinuses that were <1/3 opacified by fluid, 17% had a dental source of infection. In sinuses with 1/3 to 2/3 fluid opacification, 53% had an identifiable dental source, and in sinuses that were >2/3 opacified by fluid, 79% had an identifiable dental source. Mucosal thickening demonstrated a similar relationship with dental sources, so that sinuses having both >2/3 fluid opacification and moderate mucosal thickening were 86% likely to have an identifiable dental source.

Conclusions:

Odontogenic infections are often the source of acute maxillary sinusitis, especially if the radiographic findings of sinusitis are severe. Laryngoscope, 2009
Substernal goiters and sternotomy
Authors: Cohen Jason P.
Published: January 2009

Objective:

To determine what factors predispose patients with retrosternal goiters to median sternotomy.

Study Design:

Retrospective review.

Methods:

Analysis of a single surgeon experience with 113 substernal goiters operated upon during a 10‐year period.

Results:

108 goiters were successfully removed through a cervical approach. Four patients required sternotomy, and it was concluded that one patient who did not receive sternotomy might have been better managed with sternotomy. Factors that led to sternotomy were malignancy, involvement of the posterior mediastinum, extensive substernal extension, and the presence of an ectopic nodule. The latter two were the most important factors. Revision surgery and tracheal compression did not influence the need for sternotomy.

Conclusions:

On the basis of preoperative imaging, it is possible to predict which patients with retrosternal goiters are likely to require median sternotomy. These factors are malignancy, extension into the posterior mediastinum, substernal extension inferior to the level of the aortic arch, and the lack of a solid attachment between the cervical and mediastinal components of the thyroid gland. Although previously reported, the latter factor has not received sufficient recognition in the management of retrosternal goiter. Laryngoscope, 2009
On the propagation of uncertainty in weather radar estimates of rainfall through hydrological models
Authors: Collier Chris. G.
Published: January 2009

The generation of flow forecasts using rainfall inputs to hydrological models has been developed over many years. Unfortunately, errors in input data to models may vary considerably depending upon the different sources of data such as raingauges, radar and high resolution Numerical Weather Prediction (NWP) models. This has hampered the operational use of radar for quantitative flow forecasting. The manner with which radar rainfall input and model parametric uncertainty influence the character of the flow simulation uncertainty in hydrological models has been investigated by several authors. In this paper an approach to this problem based upon a stochastic hydrological model is considered. The errors in the input data, although they may be constrained, do propagate through the model to the flow predictions. Previous work on this error propagation through a fully distributed model is described, and a similar analysis for a stochastic hydrological model implemented in a mixed rural and urban area in north‐west England carried out. Results are compared with those previously published for an American catchment. A possible approach to selecting flow forecast ensemble members is proposed. Copyright © 2009 Royal Meteorological Society