bluuebunny/crossref_metadata_2025 huggingface dataset:
Persulfate/ascorbic acid initiated synthesis of poly(acrylonitrile)‐grafted tamarind seed gum: A potential commercial gum
Authors: Singh Vandana , Tripathi Devendra Narayan , Malviya Tulika , Sanghi Rashmi
Published: October 2008

Acrylonitrile was grafted on to tamarind seed gum using persulfate/ascorbic acid redox initiator and a representative sample of the graft copolymer (Tm‐g‐PAN) was characterized using infrared spectroscopy (FTIR), X‐ray diffraction (XRD) and scanning electron microscopy (SEM). Grafting conditions were optimized where %G and %E were found to increase with the increase in the concentration of the monomer; initiator, and the reaction temperature, whereas increase in gum concentration decreased the %G in the concentration range of 4–12 g/L, The maximum % grafting (%G) and % efficiency (%E) achieved were 305 and 75%, respectively. Water/saline retention, gel forming ability, and the shelf life of the grafted gum solutions were also studied to explore the possibility of its commercial utilization. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Evaluation of critical incidents in general surgery
Authors: Zingg U , Zala-Mezoe E , Kuenzle B , Licht A , Metzger U , Grote G , Platz A
Published: October 2008

Background

The analysis of adverse events is a central step in critical incident reporting, but has not been described in a surgical setting. The aim of this study was to develop an evaluation protocol and assess its feasibility.

Methods

All incidents were analysed by a multidisciplinary team. A coding system based on three published theories was used to assess all incidents and their underlying causes. A risk analysis was also conducted.

Results

Between July 2004 and December 2005, 9785 inpatients were treated and 139 critical incidents reported. Classification of active errors revealed 47·7 per cent to be execution failures and 45·9 per cent knowledge-based errors. The distribution of medical errors was 12·9 per cent diagnostic, 46·0 per cent treatment, 17·3 per cent preventive and 23·7 per cent other. Some 282 latent failures were identified among the 139 incidents. Risk analysis revealed a severe incident rate of 21·6 per cent.

Conclusion

This study has shown the feasibility of an evaluation protocol based on a combination of three classification systems and a risk analysis. It allows a thorough assessment of critical incidents, identification of priorities and tailored countermeasures.
Long-term follow-up of proximal versus distal laparoscopic gastric bypass for morbid obesity
Authors: Müller M K , Räder S , Wildi S , Hauser R , Clavien P-A , Weber M
Published: October 2008

Background

Laparoscopic gastric bypass is the ‘gold standard’ for treatment of morbidly obese patients in many centres. There is debate regarding the optimal length for small bowel limbs. This study aimed to determine whether the proximal or distal approach is better.

Methods

Twenty-five patients undergoing primary distal gastric bypass in 2000–2002 were randomly matched for age, sex and preoperative body mass index (BMI) with 25 patients having a primary proximal bypass. All distal operations were performed laparoscopically; one proximal procedure was converted to open surgery.

Results

Mean operating time was 170 min for proximal and 242 min for distal bypasses (P = 0·004); median hospital stay was similar in the two groups. There were no deaths and the overall complication rate was similar, as was weight loss at 4 years: BMI decreased from 45·9 to 31·7 kg/m2 for the proximal and from 45·8 to 33·1 kg/m2 for the distal approach. Co-morbidities decreased after surgery in both groups; the prevalence of diabetes, arterial hypertension and dyslipidaemia at all time points was similar in the two groups.

Conclusion

Proximal and distal laparoscopic gastric bypass operations are feasible and safe, with no differences in weight loss or reduction of co-morbidity in unselected morbidly obese patients.
Pancreas-preserving total duodenectomy versus standard pancreatoduodenectomy for patients with familial adenomatous polyposis and polyps in the duodenum
Authors: de Castro S M M , van Eijck C H J , Rutten J P , Dejong C H , van Goor H , Busch O R C , Gouma D J
Published: October 2008

Background

Pancreas-preserving total duodenectomy (PPTD) was introduced as a replacement for pancreatoduodenectomy (PD) for familial adenomatous polyposis (FAP). This study analysed the results of PPTD in the Netherlands and reviewed the relevant literature.

Methods

All 26 patients who underwent PPTD for FAP in four centres in the Netherlands between January 2000 and January 2007 were compared with a group of 77 patients who had PD for ampulla of Vater adenocarcinoma at one centre during the same interval.

Results

Morbidity rates were similar after PPTD for FAP (16 patients, 62 per cent) and PD for ampulla of Vater adenocarcinoma (44 patients, 57 per cent) (P = 0·694). One patient (4 per cent) died after PPTD and two (3 per cent) after PD. A review of the literature, including patients from the present study, found that 71 patients had PPTD, with postoperative morbidity in 36 (51 per cent) and one death (1 per cent). In publications containing a total of 94 patients who underwent PD for FAP, 43 (46 per cent) developed complications and three (3 per cent) died.

Conclusion

PPTD has similar short-term results to PD in terms of morbidity and mortality.
Predictors of symptomatic and objective outcomes after surgical reintervention for failed antireflux surgery
Authors: Furnée E J B , Draaisma W A , Broeders I A M J , Smout A J P M , Vlek A L M , Gooszen H G
Published: October 2008

Background

Recurrent gastro-oesophageal reflux disease (GORD) and troublesome dysphagia after primary antireflux surgery are treated successfully by reoperation in 70 per cent of patients. Identifying predictors of outcome could allow selection of patients likely to benefit from further surgery. The aim was to identify such predictors in patients reoperated on for recurrent GORD or troublesome dysphagia.

Methods

Between 1994 and 2005, 83 patients (mean(s.d.) age 47·2(14·4) years; 47 men) with recurrent GORD and 47 (aged 50·7(13·4) years; 18 men) with troublesome dysphagia had further surgery. The predictive values of demographic, anatomical and manometric variables, and 24-h pH monitoring were analysed with respect to symptomatic and objective outcomes in each group.

Results

None of the factors included in a multivariable analysis predicted outcome after surgery for recurrent GORD. Independent predictors of symptomatic outcome after reoperation for dysphagia were amplitude of distal oesophageal contractions (odds ratio (OR) 1·613 (95 per cent confidence interval (c.i.) 1·087 to 2·393); P = 0·017), intrathoracic wrap migration (OR 0·077 (0·003 to 1·755); P = 0·108) and an abdominal approach (OR 0·012 (0·001 to 0·337); P = 0·009).

Conclusion

Low-amplitude distal oesophageal contractions, intrathoracic wrap migration and an abdominal approach were significant predictors of an unsuccessful symptomatic outcome after reoperation for troublesome dysphagia.
False-negative sentinel lymph node biopsy
Authors: van Wely B J , Smidt M L , de Kievit I M , Wauters C A P , Strobbe L J A
Published: October 2008

Background

The clinical significance of false-negative axillary sentinel lymph node (SLN) biopsy has yet to be established. The aim of this study was to assess the axillary recurrence rate and false-negative rate, to identify prognostic factors and to monitor survival.

Methods

A prospective registry of sentinel lymph node biopsy (SLNB) procedures performed between 1998 and 2004 was analysed. All nodes retrieved were examined by haematoxylin and eosin and immunohistochemical staining. Further surgical treatment was performed only for positive SLNs. Adjuvant treatment was given according to Dutch guidelines.

Results

Of 592 patients, 392 had a negative SLNB. After a median follow-up of 65 months, 11 patients developed axillary recurrence (2·8 per cent). Ten of these patients were primarily treated by simple mastectomy and therefore had no external-beam radiation therapy; no further prognostic factors could be identified. The false-negative rate was 6·9 per cent. The median time from SLNB to detection of the axillary recurrence was 27 months. The median follow-up after recurrence was 35 months, and one patient developed systemic disease. Pathology revision revealed two previously undetected micrometastases.

Conclusion

Axillary recurrence and false-negative rates after SLNB increase with longer follow-up.
The surgical application of point-of-care haemostasis and platelet function testing
Authors: Dickinson K J , Troxler M , Homer-Vanniasinkam S
Published: October 2008

Background

Disordered coagulation complicates many diseases and their treatments, often predisposing to haemorrhage. Conversely, patients with cardiovascular disease who demonstrate antiplatelet resistance may be at increased thromboembolic risk. Prompt identification of these patients facilitates optimization of haemostatic dysfunction. Point-of-care (POC) tests are performed ‘near patient’ to provide a rapid assessment of haemostasis and platelet function.

Methods

This article reviews situations in which POC tests may guide surgical practice. Their limitations and potential developments are discussed. The paper is based on a Medline and PubMed search for English language articles on POC haemostasis and platelet function testing in surgical practice.

Results

POC tests identifying perioperative bleeding tendency are already widely used in cardiovascular and hepatic surgery. They are associated with reduced blood loss and transfusion requirements. POC tests to identify thrombotic predisposition are able to determine antiplatelet resistance, predicting thromboembolic risk. So far, however, these tests remain research tools.

Conclusion

POC haemostasis testing is a growing field in surgical practice. Such testing can be correlated with improved clinical outcome.
Randomized clinical trial of stapled haemorrhoidopexy performed under local perianal block versus general anaesthesia
Authors: Gerjy R , Lindhoff-Larson A , Sjödahl R , Nyström P-O
Published: October 2008

Background

The aim was to assess the feasibility of performing stapled haemorrhoidopexy under local anaesthesia.

Methods

Fifty-eight patients with haemorrhoid prolapse were randomized to receive local or general anaesthesia. The perianal block was applied immediately peripheral to the external sphincter. Submucosal block was added after applying the purse-string suture. Patients reported average and peak pain daily for 14 days using a visual analogue scale (VAS). They also completed anal symptom questionnaires before the operation and at follow-up. The surgeon assessed the restoration of the anal anatomy 3–6 months after surgery.

Results

The anal block was sufficient in all patients. The mean accumulated VAS score for average pain was 23·1 in the general anaesthesia group and 29·4 in the local anaesthesia group (P = 0·376); mean peak pain scores were 42·1 and 47·9 respectively (P = 0·537). Mean change in symptom load was also similar between the groups, with score differences of 7·0 in the general anaesthesia group and 6·1 in the local anaesthesia group. No patient had a recurrence of prolapse.

Conclusion

Perianal local block is easy to apply with a high degree of acceptability among patients. Postoperative pain, restoration of anatomy and symptom resolution were similar to that of stapled haemorrhoidopexy performed under general anaesthesia. Registration number: ISRCTN19930199 (http://www.controlled-trials.com).
Letter 1: Use of enoxaparin results in more haemorrhagic complications after breast surgery than unfractionated heparin (Br J Surg 2008; 95: 834–836)
Authors: Kittisupamongkol W
Published: October 2008

The Editors welcome topical correspondence from readers relating to articles published in the Journal. Responses should be sent electronically via the BJS website (www.bjs.co.uk). All letters will be reviewed and, if approved,appear on the website. A selection of these will be edited and published in the Journal. Letters must be no more than 250 words in length.
Synthesis of Isoxazolopyridobicyclooxacalix[4]arenes: A New Family of Heteracalixarene Systems
Authors: Ferrini Serena , Fusi Stefania , Giorgi Gianluca , Ponticelli Fabio
Published: October 2008

A new family of isoxazolopyridobicyclooxacalix[4]arenes was obtained by reaction of dichloroisoxazolopyridines with phloroglucinol. X‐ray crystallography and density functional calculations were used for their structural determination and evaluation of their chemical properties. Their role as metal chelators was studied by mass spectrometry. This new family of heteracalixarenes is of potential interest for host–guest interactions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Development and characterization of hepatitis C virus genotype 1-7 cell culture systems: Role of CD81 and scavenger receptor class B type I and effect of antiviral drugs # †
Authors: Gottwein Judith M. , Scheel Troels K. H. , Jensen Tanja B. , Lademann Jacob B. , Prentoe Jannick C. , Knudsen Maria L. , Hoegh Anne M. , Bukh Jens
Published: October 2008

Six major hepatitis C virus (HCV) genotypes and numerous subtypes have been described, and recently a seventh major genotype was discovered. Genotypes show significant molecular and clinical differences, such as differential response to combination therapy with interferon-α and ribavirin. Recently, HCV research has been accelerated by cell culture systems based on the unique growth capacity of strain JFH1 (genotype 2a). By development of JFH1-based intergenotypic recombinants containing Core, envelope protein 1 and 2 (E1, E2), p7, and nonstructural protein 2 (NS2) of genotype 6a and 7a strains, as well as subtype 1b and 2b strains, we have completed a panel of culture systems for all major HCV genotypes. Efficient growth in Huh7.5 cells depended on adaptive mutations for HK6a/JFH1 (6a/2a, in E1 and E2) and J4/JFH1 (1b/2a, in NS2 and NS3); viability of J8/JFH1 (2b/2a) and QC69/JFH1 (7a/2a) did not require adaptation. To facilitate comparative studies, we generated virus stocks of genotype 1–7 recombinants with infectivity titers of 103.7 to 105.2 50% tissue culture infectious dose/mL and HCV RNA titers of 107.0 to 107.9 IU/mL. Huh7.5 cultures infected with genotype 1–6 viruses had similar spread kinetics, intracellular Core, NS5A, and lipid amounts, and colocalization of Core and NS5A with lipids. Treatment with interferon-α2b but not ribavirin or amantadine showed a significant antiviral effect. Infection with all genotypes could be blocked by specific antibodies against the putative coreceptors CD81 and scavenger receptor class B type I in a dose-dependent manner. Finally, neutralizing antibodies in selected chronic phase HCV sera had differential effects against genotype 1–7 viruses. Conclusion: We completed and characterized a panel of JFH1-based cell culture systems of all seven major HCV genotypes and important subtypes and used these viruses in comparative studies of antivirals, HCV receptor interaction, and neutralizing antibodies. (Hepatology 2009.)
Steam absorption into films of aqueous solution of lithium bromide and lithium iodide mixture falling over a column of horizontal pipes
Authors: Kiyota Masanori , Morioka Itsuki , Kimoto Keisuke , Suekane Tetsuya
Published: October 2008

To improve absorption chiller performance, an aqueous solution of lithium bromide and lithium iodide mixture at the ratio of 1:0.7 was proposed for an absorbing medium since it has a higher solution limit than conventional lithium bromide solution. But the component lithium iodide solution has a higher equilibrium pressure than the lithium bromide solution. To investigate the absorption performance of the mixture liquid, experiments were carried out using a horizontal pipe column. Experimental range of the mass concentration was 62–66% for the mixture solution and 62–63% for the lithium bromide solution. The absorption rate of lithium bromide solution at 62% and 63% is almost equal to the mixture solution at 63% and 64%, respectively. Compared at the same concentrations, the mixture solution is inferior to the lithium bromide solution; at the maximum concentration, the mixture solution has about 20 to 50% higher absorption rates than the lithium bromide solution. Surface temperature of the falling films was measured by thermal video and used to determine the heat transfer coefficient and mass transfer coefficient, which becomes larger for the mixture solution than for the lithium bromide solution. This is due to the decreased viscosity of the mixture solution. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(7): 431–444, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20213
Identifying rotation and oscillation in surface tension measurement using an oscillating droplet method
Authors: Ozawa Shumpei , Koda Takuro , Adachi Masayoshi , Shiratori Suguru , Takenaga Noriaki , Hibiya Taketoshi , Watanabe Masahito
Published: October 2008

We proposed a new approach to identify the frequencies of droplet rotation and m=±2 oscillation that degrade the accuracy of surface tension measurement by an oscillating droplet method. Frequencies of droplet rotation and m=±2 oscillation can be identified by a phase unwrapping analysis of time dependence of the deflection angle for the maximum diameter of the droplet image observed from above. The present method was validated, using test data with given frequencies. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(7): 421–430, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20214
Frost formation on a bionic super‐hydrophobic surface under natural convection conditions
Authors: Gou Yunjun , Liu Zhongliang , Wang Jieteng , Cheng Shuiyuan
Published: October 2008

A bionic super‐hydrophobic surface has a multiple micro‐nano‐binary structure (MNBS) similar to the lotus leaf surface microstructure. This kind of surface has a contact angle of water greater than 150° and a roll angle smaller than 5°. In this paper, the frost deposition phenomena on a bionic super‐hydrophobic surface were observed. The surface has many micro bumps and its contact angle is 162°. The formation of water droplets, the droplet freezing process, the formation of initial frost crystals and the frost layer structure on a cold bionic super‐hydrophobic surface under natural convection conditions were closely observed. The frost layer structure formed on the super‐hydrophobic surface shows remarkable differences to that on a plain copper surface: the structure is weaker, looser, thin, and easily removed and most importantly, it is of a very special pattern, a pattern similar to a chrysanthemum, a frost layer structure that has not been reported before to the best of the present authors knowledge. The experimental results also show that a super‐hydrophobic surface has a strong ability to restrain frost growth. The frost deposition on this bionic surface was delayed 55 minutes when compared with a plain copper surface under the conditions of a cold plate temperature of −10.1°C, air temperature of 18.4°C, and relative humidity of 40%. A theoretical analysis was also presented to explain the observed phenomena. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(7): 412–420, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20216
TCEB1 promotes invasion of prostate cancer cells
Authors: Jalava Sanni E. , Porkka Kati P. , Rauhala Hanna E. , Isotalo Jarkko , Tammela Teuvo L. , Visakorpi Tapio
Published: October 2008

Amplification of the long arm of chromosome 8 is one of the most recurrent findings in prostate cancer and it is associated with poor prognosis. Several minimal regions of amplification suggest multiple target genes which are yet to be identified. We have previously shown that TCEB1, EIF3S3, KIAA0196 and RAD21 are amplified and overexpressed in prostate cancer and they are located in the 8q area. In this study, we examined the functional effects of these genes to prostate cancer cell phenotype. We overexpressed and inhibited the genes by lentivirus mediated overexpression and RNA interference, respectively. shRNA mediated TCEB1 silencing decreased significantly cellular invasion of PC‐3 and DU145 cells through Matrigel. TCEB1 silencing reduced the anchorage‐independent growth of PC‐3 cells. Similar effects were not seen with any other genes. When overexpressed in NIH 3T3 cells, TCEB1 and EIF3S3 increased the growth rate of the cells. Transcriptional profiling of TCEB1 silenced PC‐3 cells revealed decrease of genes involved in invasion and metastasis. Finally, we also confirmed here the overexpression of TCEB1 in hormone‐refractory prostate tumors. This study indicates that TCEB1 promotes invasion of prostate cancer cells, is involved in development of hormone‐refractory prostate cancer and is thereby a strong candidate to be one of the target genes for the 8q gain. © 2008 Wiley‐Liss, Inc.
How many cervical cancers are prevented by treatment of screen‐detected disease in young women?
Authors: Sasieni Peter , Castanon Alejandra , Parkin D. Max
Published: October 2008

Others have argued that as many as a third of women treated for high‐grade cervical intraepithelial neoplasia (CIN) would have developed cervical cancer in the absence of screening and treatment. Under various assumptions and using past data on CIN grade 3 (CIN3) registrations in England and Scotland, we estimate what cervical cancer rates would have been in the absence of screening. Data on registrations of cervical carcinoma in situ for England and Scotland were used to project the additional numbers of invasive cervical cancers that would have resulted had the carcinoma in situ not been treated. We compare the resulting cervical cancer rates (under different models) with rates recorded in Cancer Incidence in 5 Continents. In order for the projected rates in England and Scotland at ages 20–24 not to be exceptionally high compared to maximum recorded rates for each registry in Cancer Incidence in 5 Continents, the progression rate from CIN3 to invasive cancer in women aged 20–24 should not exceed 1% per year. Similar progression rates were reasonable for women aged 25–29. Under the previously accepted assumption of 4.33% progression per year, cervical cancer rates in women aged 20–29 in both England and Scotland would have been 2–5 times greater than any observed rate (other than one registry, based on just 4 cases). From this analysis, at most 1.5% of women treated (equivalent to 3% of CIN3 registrations) would have had cancer by age 25, whereas it is reasonable to assume that over half of them would have regressed by age 25. © 2008 Wiley‐Liss, Inc.
Cholinergic signaling through nicotinic acetylcholine receptors stimulates the proliferation of cervical cancer cells: An explanation for the molecular role of tobacco smoking in cervical carcinogenesis?
Authors: Calleja‐Macias Itzel E. , Kalantari Mina , Bernard Hans‐Ulrich
Published: October 2008

We have analyzed the expression of mRNAs encoding nicotinic acetylcholine receptors (nAChRs) in CaSki, SiHa and HeLa cell lines, which are derived from two squamous and one adenocarcinoma of the cervix, respectively. We detected with reverse transcription‐polymerase chain reaction mRNAs for ten of the 16 nAChR subunits, namely strong signals for alpha‐5, alpha‐7, alpha‐9, beta‐1 and epsilon, and weak signals for alpha‐4, beta‐2, beta‐4, gamma and delta. We confirmed the translation of alpha‐5 and beta‐1, corresponding to the two strongest RNA signals, in SiHa and HeLa cells by Western blotting, and the localization of these proteins to the plasma membrane by immunofluorescence. The beta‐1 subunit was detected membrane‐associated in normal and neoplastic squamous epithelia of the cervix in situ, but appeared to be absent from the underlying mesenchyme and even from adjacent columnar epithelia. These observations suggest that normal and neoplastic cervical squamous epithelial cells express several combinations of the pentameric nAChRs. We also measured that the proliferation of SiHa and HeLa cells is stimulated by nicotine. This indicates that cholinergic signaling under normal physiological conditions and stimulated by nicotine in tobacco users affects epithelial homeostasis and neoplastic progression at the cervix in a way similar to the known effects on epithelia of the mouth, the airways and the lung. Since tobacco smoking is established as a risk factor in cervical carcinogenesis, and since nicotine and its derivatives become concentrated in cervical mucus, nAChR‐dependent signaling is apparently an important molecular cofactor of human papillomavirus‐dependent cervical carcinogenesis. © 2008 Wiley‐Liss, Inc.
International liquidity swaps: is the Chiang Mai Initiative pooling reserves efficiently?
Authors: Kohlscheen E. , Taylor M. P.
Published: October 2008

We analyse the network of bilateral liquidity swaps (BSAs) among the ASEAN+3 countries. We find that the network has taken the correlation of capital flows in the region into account, in the sense that countries with lower correlation of reserve growth have engaged in larger BSAs. All else equal, a decimal point increase in the correlation of international reserve growth decreases the size of a bilateral swap agreement between 18% and 27%. Moreover, we find that the approximately $ 60 bn of BSAs have had a limited impact, if any, on government bond spreads so far. Finally, we identify potential gains from inter‐regional BSAs. Copyright © 2008 John Wiley & Sons, Ltd.
Convergence of integrins and EGF receptor signaling via PI3K/Akt/FoxO pathway in early gene Egr‐1 expression
Authors: Cabodi Sara , Morello Virginia , Masi Alessio , Cicchi Riccardo , Broggio Chiara , DiStefano Paola , Brunelli Elisa , Silengo Lorenzo , Pavone Francesco , Arcangeli Annarosa , Turco Emilia , Tarone Guido , Moro Laura , Defilippi Paola
Published: October 2008

The early gene early growth response (Egr‐1), a broadly expressed member of the zing‐finger family of transcription factors, is induced in many cell types by a variety of growth and differentiation stimuli, including epidermal growth factor (EGF). Here we demonstrate that Egr‐1 expression is mainly regulated by integrin‐mediated adhesion. Integrin‐dependent adhesion plays a dual role in Egr‐1 regulation, either being sufficient “per se” to induce Egr‐1, or required for EGF‐dependent expression of Egr‐1, which occurs only in adherent cells and not in cells in suspension. To dissect the molecular basis of integrin‐dependent Egr‐1 regulation, we show by FLIM‐based FRET that in living cells beta1‐integrin associates with the EGF receptor (EGFR) and that EGF further increases the extent complex formation. Interestingly, Egr‐1 induction depends on integrin‐dependent PI3K/Akt activation, as indicated by the decrease in Egr‐1 levels in presence of the pharmacological inhibitor LY294002, the kinase‐defective Akt mutant and Akt1/2 shRNAs. Indeed, upon adhesion activated Akt translocates into the nucleus and phosphorylates FoxO1, a Forkhead transcription factors. Consistently, FoxO1silencing results in Egr‐1‐increased levels, indicating that FoxO1 behaves as a negative regulator of Egr‐1 expression. These data demonstrate that integrin/EGFR cross‐talk is required for expression of Egr‐1 through a novel regulatory cascade involving the activation of the PI3K/Akt/Forkhead pathway. J. Cell. Physiol. 218: 294–303, 2009. © 2008 Wiley‐Liss, Inc.
How TRW Automotive helps global virtual teams perform at the top of their game
Authors: Duckworth Holly
Published: October 2008

Global virtual teams have the deck stacked against them: long distances, cultural differences, lack of social cues to help gauge each other's trustworthiness—and leaders unprepared to deal with these challenges. What such teams need for success are special leadership, consistent work practices, and keen attention to communication and building trust through a focus on member commitment and competency. TRW Automotive trains its continuous improvement leaders on how to apply the Goals, Roles, Processes, and Interpersonal Relationships (GRPI) Model with their far‐flung virtual project members to create the all‐important interdependent relationships and team cohesion in the absence of face‐to‐face interactions. © 2008 Wiley Periodicals, Inc.
Synthesis and characterization of organic/inorganic hybrid star polymers of 2,2,3,4,4,4‐hexafluorobutyl methacrylate and octa(aminophenyl)silsesquioxane nano‐cage made via atom transfer radical polymerization
Authors: Hussain H. , Tan B. H. , Gudipati C. S. , Xaio Y. , Liu Y. , Davis Thomas P. , He C.B.
Published: October 2008

Well‐defined organic/inorganic hybrid fluorinated star polymers were synthesized via atom transfer radical polymerization (ATRP) of 2,2,3,4,4,4‐hexafluorobutyl methacrylate (HFBMA) using octa(aminophenyl)silsesquioxane (OAPS) nano‐cage as initiator. For this purpose, OAPS was transformed into ATRP initiator by reacting with 2‐bromoisobutyrylbromide. ATR polymerization of HFBMA was carried out in trifluorotoluene at 75 °C using CuCl/2,2‐bipyridine or N,N,N′,N″,N″‐pentamethyldiethylenetriamine as catalyst system. GPC and 1H NMR data confirmed the synthesis of OAPS/PHFBMA hybrid star polymer. Kinetics of the ATR polymerization of HFBMA using OAPS nano‐cage initiator was also investigated. The OAPS/PHFBMA hybrid stars were found to be molecularly dispersed in solution (THF); however, TEM micrographs revealed the formation of spherical particles of ∼ 120–180 nm by the OAPS/PHFBMA hybrid star polymer after solvent evaporation. Thermal characterization of the nanocomposites by differential scanning calorimetry (DSC) revealed a slightly higher glass transition temperature (Tg) (when compared with the linear PHFBMA) of higher molecular weight OAPS/PHFBMA hybrid star polymers. In contrast, lower Tg than the linear PHFBMA was observed for OAPS/PHFBMA of relatively lower molecular weight (but higher than the linear PHFBMA). Thermal gravimetric analysis (TGA) showed a significant retardation (by ∼60 °C) in thermal decomposition of nanocomposites when compared with the linear PHFBMA. Additionally, surface properties were evaluated by measuring the contact angles of water on polymer surfaces. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7287–7298, 2008
Titanium tetrachloride supported on atom transfer radical polymerized poly(methyl acrylate‐co‐1‐octene) as catalyst for ethylene polymerization
Authors: Kaur Sukhdeep , Singh Gurmeet , Gupta Virendra K.
Published: October 2008

Ethylene polymerizations were performed using catalyst based on titanium tetrachloride (TiCl4) supported on synthesized poly(methyl acrylate‐co‐1‐octene) (PMO). Three catalysts were synthesized by varying TiCl4/PMO weight ratio in chlorobenzene resulting in incorporation of titanium in different percentage as determined by UV‐vis spectroscopy. The coordination of titanium with the copolymer matrix was confirmed by FTIR studies. The catalysts morphology as observed by SEM was found to be round shaped with even distributions of titanium and chlorine on the surface of catalyst. Their performance was evaluated for atmospheric polymerization of ethylene in n‐hexane using triethylaluminum as cocatalyst. Catalyst with titanium incorporation corresponding to 2.8 wt % showed maximum activity. Polyethylenes obtained were characterized for melting temperature, molecular weight, morphology and microstructure. The polymeric support utilized for TiCl4 was synthesized using activators regenerated by electron transfer (ARGET) Atom Transfer Radical Polymerization (ATRP) of methyl acrylate (MA) and 1‐octene (Oct) with Cu(0)/CuBr2/tris(2‐(dimethylamino)ethyl)amine (Me6TREN) as catalyst and ethyl 2‐bromoisobutyrate (EBriB) as initiator at 80 °C. The copolymer poly(methyl acrylate‐1‐octene; PMO) obtained showed monomodal curve in Gel Permeation Chromatography (GPC) with polydispersity of 1.37 and copolymer composition (1H NMR; FMA) of 0.75. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7299–7309, 2008
Block copolymer micelles conjugated with anti‐EGFR antibody for targeted delivery of anticancer drug
Authors: Noh Taiho , Kook Yeon Hee , Park Chiyoung , Youn Hyewon , Kim Hana , Oh Eun Tax , Choi Eun Kyung , Park Heon Joo , Kim Chulhee
Published: October 2008

Antiepidermal growth factor receptor antibody (anti‐EGFR antibody) was conjugated with the block copolymer micelle based on poly(ethylene glycol) (PEG) and poly(ε‐caprolactone) (PCL) for active targeting to EGFR overexpressing cancer cells. Doxorubicin (DOX) was encapsulated in the core of the block copolymer (MePEG‐b‐PCL) micelle (DOX‐micelle). The mean diameters of the DOX‐micelle and the anti‐EGFR‐PEG‐b‐PCL copolymer micelles loaded with DOX (DOX‐anti‐EGFR‐micelle) were about 25 and 31 nm, respectively. The RKO human colorectal cancer cells expressing moderate degree of EGFR were incubated with free DOX, DOX‐micelle, or DOX‐anti‐EGFR‐micelle to study the distribution of DOX in the cells. When cells were incubated with free DOX, moderate degree of DOX fluorescence was observed in the nuclei. In the cells treated with DOX‐micelle, the DOX fluorescence intensity in the cytoplasm was much greater than that in the nuclei. On the other hand, the nuclei of the cells treated with DOX‐anti‐EGFR‐micelle exhibited DOX fluorescence intensity similar to that in the cytoplasm. The cytotoxicity of DOX‐anti‐EGFR‐micelle to induce apoptosis in RKO cells was significantly greater than that of free DOX or DOX‐micelle. These results demonstrated that the presence of anti‐EGFR antibody on the DOX‐micelle surface (DOX‐anti‐EGFR‐micelle) increased the internalization of the DOX‐micelle and nuclear accumulation of DOX, and enhanced the DOX‐induced cell death. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7321–7331, 2008
Radical and cationic photopolymerization: New pyrylium and thiopyrylium salt‐based photoinitiating systems
Authors: El‐Roz Mohamad , Lalevée Jacques , Morlet‐Savary Fabrice , Allonas Xavier , Fouassier Jean Pierre
Published: October 2008

New thiopyrylium and pyrylium salt‐based photoinitiating systems for visible light induced free radical polymerization (FRP) or free radical promoted cationic polymerization (FRPCP) under visible lights are presented. The reaction mechanisms are investigated by laser flash photolysis and the structure/reactivity trend is discussed. The abilities of two different classes of coinitiators are investigated (thiols/disulfides and silanes). In FRP, upon irradiation with a xenon lamp (λ > 390 nm), the (thio)pyrylium salts in combination with thiols or disulfides lead to very high polymerization rates, compared to the reference eosin Y/methyldiethanolamine system. In FRPCP, silanes are found much better coinitiators: a high efficiency of the photopolymerization under air is noted. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7369–7375, 2008
Degradation of RAFT polymers in a cyclic ether studied via high resolution ESI‐MS: Implications for synthesis, storage, and end‐group modification
Authors: Gruendling Till , Pickford Russell , Guilhaus Michael , Barner‐Kowollik Christopher
Published: October 2008

We report on the detailed mass spectrometric analysis of the degradation products generated during storage of poly(methyl methacrylate) (pMMA) and polystyrene (pSty) carrying cumyldithiobenzoate (CDB) endgroups. Samples were stored in either a cyclic ether (tetrahydrofuran) (THF) or an inert solvent (dichloromethane). The degradation process was followed over a period of 4‐weeks. Degradation rate of the reversible addition fragmentation (RAFT) polymer strongly depends on the hydroperoxide‐content of the solvent. Mass spectrometric evidence supports an unexpected radical degradation mechanism for the pMMA macroRAFT agent. Hydroperoxide functional pMMA was the single product after less than 7 days in high purity THF. No formation of the sulfine/thioester was observed. The identity of the hydroperoxide was unambiguously assigned using accurate mass measurements by Fourier‐Transform ion‐cyclotron‐resonance mass spectrometry together with chemical identification reactions. The hydroperoxide end group formation proceeds efficiently as well as in high yields and thus constitutes a powerful method for end group modification. The degradation pathways of the CDB functional pSty in THF include mainly oxidation towards the sulfine/thioester, with little degradation via thermal elimination of dithiobenzoic acid and subsequent epoxidation. The shelf life of CDB functional polymers is limited even in inert solvent because of this inherent but slow thermal elimination reaction. Because of the short period necessary for the transformation of the functional dithiobenzyl endgroups, substitution of cyclic ethers as solvents for RAFT polymers in synthesis and analysis is strongly suggested. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7447–7461, 2008
Water‐soluble dendritic‐conjugated polyfluorenes: Synthesis, characterization, and interactions with DNA
Authors: Yu Minghui , Liu Libing , Wang Shu
Published: October 2008

Three generation of Boc‐protected dendritic‐conjugated polyfluorenes (Boc‐PFP‐G0‐2) were synthesized by Suzuki coupling 1,4‐phenyldiboronic ester with dendritic monomers that were synthesized through generation‐by‐generation approach. The gel permeation chromatography (GPC) analyses showed that the weight‐average molecular weight (Mw) of Boc‐PFP‐G0‐2 was in the range of 11,400–20,400 Da with the polydispersity index (PDI) in the range of 1.32–1.96. Treatment of Boc‐protected polymers with 6 M HCl in dioxane yielded cationic dendritic‐conjugated polyfluorenes (PFP‐G0‐2). They were soluble in common polar solvents such as DMSO, DMF, and water with absorption maxima between 345 and 379 nm. The solutions of PFP‐G0‐2 in water were highly fluorescent with emission maxima between 416 and 425 nm. Because higher generation dendrons could prevent the formation of π‐stacking aggregates of backbones of conjugated polymer, the fluorescence quantum efficiencies (QEs) of PFP‐G0‐2 enhance as the dendritic generation grew. The interactions between 25 mer double‐stranded DNA (dsDNA) and PFP‐G0‐2 were studied using ethidium bromide (EB) as fluorescent probe. The electrostatic bindings of PFP‐G0‐2 with dsDNA/EB complex result in displacement of EB from DNA double helix to the solution accompanying by a quenching of EB fluorescence. The PFP‐G2 with highest generation of dendritic side chains possessed a highest charge density and could form most stable complex with dsDNA. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7462–7472, 2008
Bismuth halide‐catalyzed polymerizations of ε‐caprolactone
Authors: Lahcini Mohammed , Schwarz Gert , Kricheldorf Hans R.
Published: October 2008

In contrast to BiF3, the other three Bi‐halides catalyzed the ring‐opening polymerization of ε‐caprolactone (ε‐CL) in bulk. A temperature of 140 °C was found to be advantageous for rapid polymerization and optimum molecular weights. At this temperature, the reactivity of the catalysts increases in the order BiCl3 < BiBr3 < BiJ3. Variation of the monomer‐catalyst ratio (M/C) yielded number‐average molecular weights (Mns) up to 80,000 Da (corrected SEC data, 120,000 Da uncorrected), but a proper control of the Mns was not achieved. In addition to CH2OH endgroups, CH2Cl, CH2Br, and CH2J endgroups were detected, but no evidence for a cationic polymerization mechanism was found. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7483–7490, 2008
Characterization, crystallization kinetics, and melting behavior of poly(ethylene succinate) copolyester containing 10 mol % butylene succinate
Authors: Lu Hsin‐Ying , Lu Shih‐Fu , Chen Ming , Yang Chao‐Sen , Chen Chi He , Tsai Chia‐Jung
Published: October 2008

Copolyester was synthesized and characterized as having 89.9 mol % ethylene succinate units and 10.1 mol % butylene succinate units in a random sequence, as revealed by NMR. Isothermal crystallization kinetics was studied in the temperature range (Tc) from 30 to 73 °C using differential scanning calorimetry (DSC). The melting behavior after isothermal crystallization was investigated using DSC by varying the Tc, the heating rate and the crystallization time. DSC curves showed triple melting peaks. The melting behavior indicates that the upper melting peaks are associated primarily with the melting of lamellar crystals with various stabilities. As the Tc increases, the contribution of recrystallization slowly decreases and finally disappears. A Hoffman‐Weeks linear plot gives an equilibrium melting temperature of 107.0 °C. The spherulite growth of this copolyester from 80 to 20 °C at a cooling rate of 2 or 4 °C/min was monitored and recorded using an optical microscope equipped with a CCD camera. Continuous growth rates between melting and glass transition temperatures can be obtained after curve‐fitting procedures. These data fit well with those data points measured in the isothermal experiments. These data were analyzed with the Hoffman and Lauritzen theory. A regime II → III transition was detected at around 52 °C. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2431–2442, 2008
Surface phonon polariton modes of wurtzite structure Alx Ga1–xN thin film
Authors: Zhang L. , Shi J.‐J.
Published: October 2008

The polar phonon polariton modes in a wurtzite thin film structure are theoretically investigated in the present paper. It is confirmed that there are two types of phonon polariton modes, i.e. the surface phonon polariton (SPP) modes and the confined phonon polariton (CPP) modes in wurtzite thin film systems. The frequency ranges of the SPP and CPP modes are discussed in detail. The dispersive equation of the SPP modes is also deduced. Numerical calculations on Alx Ga1–x N thin film structures reveal that, for a given free wave number kt in the x ‐direction, there are two branches of SPP modes in general. The Al concentration x of Alx Ga1–x N materials and the thickness d of the wurtzite thin film have an important influence on the dispersive properties of the polariton modes, especially as the thickness d is small. Our calculated results are completely consistent with the recent experimental observation in Alx Ga1–x N thin film systems. We confirm that the SPP modes observed are the low‐frequency branches of SPP modes. Furthermore, the frequency values of the high‐frequency branches of SPP modes are explicitly given, and a possible method for observing these high‐frequency SPP modes is also brought forward. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
EXAFS analysis of blue luminescence in polyoxytungstate citrate gels
Authors: De Buysser Klaartje , Van Driessche Isabel , Vermeir Pieter , Thuy Tran Thi , Schaubroeck Joseph , Hoste Serge
Published: October 2008

Remarkable color changes can be seen when ammonium metatungstate – citric acid gels are submitted to sunlight. The colors strongly depend of the pH values of the precursor solution. Luminescence measurements reveal that gels at pH 7 exhibit a strong blue emission resulting from the presences of WO42– tetrahedra while a slight green emission is due to WO66– octahedra. The shift in equilibrium from octahedral to tetrahedral coordination upon increase in pH is confirmed by detailed EXAFS analysis. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Auxeticity of Calcite and Aragonite polymorphs of CaCO3 and crystals of similar structure
Authors: Aouni Nizar , Wheeler Lewis
Published: October 2008

Auxeticity of Calcium Carbonate CaCO3 is explored for the polymorphs commonly known as calcite, which is trigonal, and aragonite, which is orthorhombic. A decomposition of the compliance tensor is presented for the trigonal and orthorhombic classes that simplifies the analysis of extreme values of Lamé compliance and Poisson's ratio. Simple criteria for the determination of auxeticity are proposed and discussed for a wide variety of trigonal and orthorhombic crystals. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Pharmacological and biological screening of ascorbigen: protection against glucose‐induced endothelial cell toxicity
Authors: Joshi Mandar S. , Bauer John A. , Werbovetz Karl A. , Barszcz Todd , Patil Popat N.
Published: October 2008

Cruciferous vegetables contain significant amounts of ascorbigen and related substances with known molecular structures. This study tested the hypothesis that ascorbigen demonstrates antioxidant properties and protects human umbilical cord endothelial cells against hyperglycemic toxicity in vitro. It was observed that ascorbigen, in micromolar concentrations, protected against endothelial cell death from glucose toxicity. Additionally, ascorbigen at 3.0 mm shifted the concentration response curve of l‐phenylephrine to the right, with a reduction in the maximal contractile effects of the agonist. This action was not related to α‐adrenoceptor blockade. Ascorbigen also relaxed the vascular tone induced by l‐phenylephrine, which is not mediated by an endothelial cell nitric oxide‐dependent mechanism. On the guinea‐pig ileum, the spasmogenic effects of carbachol, histamine and serotonin were reduced in the presence of 3 mm ascorbigen. Spasm of the gut induced by the acetylcholinesterase inhibitor, physostigmine, was antagonized by ascorbigen with an IC50 of 286 µm. This natural product also has a weak antiparasitic activity. The cytoprotective effects of ascorbigen may be highly relevant in the optimum physiological regulation of the function and the therapeutic value of this substance in disease settings needs to be further investigated. Copyright © 2008 John Wiley & Sons, Ltd.
Extracts of Cynomorium songaricum protect SK‐N‐SH human neuroblastoma cells against staurosporine‐induced apoptosis potentially through their radical scavenging activity
Authors: Lu Yi , Wang Qingguo , Melzig Matthias F. , Jenett‐Siems Kristina
Published: October 2008

In traditional Chinese medicine a number of herbs are used to alleviate the symptoms of aging, among them the stems of Cynomorium songaricum, Cynomoriaceae. This study evaluated the protective effect of different extracts of C. songaricum on staurosporine‐induced apoptotic cell death in SK‐N‐SH neuroblastoma cells. Staurosporine (100 nm) reduced cell viability to about 55%. The ethyl acetate fraction of C. songaricum significantly attenuated staurosporine‐induced cell death at concentrations of 100 and 10 µg/mL. On the other hand, the dichloromethane as well as water fractions showed no protective effects. In order to further analyse the protective mode of action, the superoxide anion scavenging activity of two extracts was evaluated in a xanthine/xanthine oxidase system. In this system, the EtOAc extract showed a good scavenging activity (IC50 value 2.9 µg/mL) without inhibition of xanthine oxidase. In conclusion, the results prove the neuroprotective activity of C. songaricum extracts in vitro, thus supporting its traditional use. Copyright © 2008 John Wiley & Sons, Ltd.
Antioxidant properties and xanthine oxidase inhibitory effects of Tamus communis L. root extracts
Authors: Boumerfeg Sabah , Baghiani Abderrahmane , Messaoudi Dalila , Khennouf Seddik , Arrar Lekhmici
Published: October 2008

This study was conducted to search for xanthine oxidase (XO) inhibitors from the root extracts of Tamus communis L. traditionally used in folk medicine in Algeria. Root extracts with different solvents were screened for purified milk xanthine oxidase inhibition. The root extracts (methanol, chloroform and ethyl acetate) and proteins, obtained in distilled water, inhibited bovine, sheep and human milk XO from three species in a concentration‐dependent manner, with an additional superoxide scavenging capacity, which reached its highest level with ethyl acetate extract (IC50 = 0.15, 0.04 and 0.09 g/L) for bovine XO, sheep XO and human XO, respectively. The antioxidant potential was confirmed with the non‐enzymatic method, total radical‐trapping antioxidant parameter (TRAP) assay, which showed that the Tamus communis L. extracts have a potential antioxidant activity in the same order obtained by using the reduction of cytochrome c, an enzymatic method, in which the antioxidant activity followed a decreasing order: ethyl acetate extract > chloroform extract > protein. Copyright © 2008 John Wiley & Sons, Ltd.