bluuebunny/crossref_metadata_2025 huggingface dataset:
Solution‐based Fabrication of High‐κ Gate Dielectrics for Next‐Generation Metal‐Oxide Semiconductor Transistors
Authors: Aoki Y. , Kunitake T.
Published: January 2004

The layer‐by‐layer adsorption of precursor metal alkoxides in solution and post‐annealing at 400 °C affords an alternate technique to the atomic layer chemical vapour deposition method for fabrication of next‐generation high‐κ gate dielectrics. A void‐free TiO2–La2O3 composite film (see Figure) with 18 nm thickness is readily fabricated, and shows a dielectric constant higher than 30.
Use of Coaxial Gas Jackets to Stabilize Taylor Cones of Volatile Solutions and to Induce Particle‐to‐Fiber Transitions
Authors: Larsen G. , Spretz R. , Velarde‐Ortiz R.
Published: January 2004

A novel method to control the stability of Taylor cones during electrospinning/electrospray of solutions with highly volatile solvents is presented. An additional advantage is that fiber‐to‐particle transitions are also controlled without changing the chemistry or the voltage/current characteristics. The Figure shows the transition from particles to fibers effected by simply changing the gas flow rate through an outer capillary.
Facile Microstructuring of Organic Semiconducting Polymers by the Breath Figure Method: Hexagonally Ordered Bubble Arrays in Rigid Rod‐Polymers
Authors: Song L. , Bly R. K. , Wilson J. N. , Bakbak S. , Park J. O. , Srinivasarao M. , Bunz U. H. F.
Published: January 2004

Microstructuring of conjugated polymers is facile utilizing the breath figure approach. Dilute solutions of conjugated polymers in carbon disulfide form highly ordered 2D hexagonal bubble arrays (see Figure and inside cover). The arrays are obtained if moist air is blown over the polymer solutions. Evaporative cooling leads to condensation of water droplets onto the liquid surface. After the solvent is evaporated, the ordered bubble array is observed.
Magnetic‐Field‐Induced Growth of Single‐Crystalline Fe3O4 Nanowires
Authors: Wang J. , Chen Q. , Zeng C. , Hou B.
Published: January 2004

Single‐crystalline nanowires of Fe3O4 hydrothermally synthesized under a magnetic field are reported. The square and hexagonal crystals formed in zero applied field are shown to give way to nanowires as the magnetic field is increased. The Figure shows the situation for a 0.25 T field. The structure and magnetic properties are characterized by transmission electron microscopy, X‐ray and electron diffraction, and magnetometry.
Crystallographic report: (2,2′‐Bipyridyl)bis(ethanoldithiocarbamato)zinc(II)
Authors: Saravanan M. , Ramalingam K. , Bocelli G. , Cantoni A.
Published: January 2004

Zn(meadtc)2(2,2′‐bipy) is a ZnS3N2 chromophore with a distorted square pyramidal geometry. The IR band at 1002 cm−1 and the bond valence sum value of 1.98 confirmed the monodentate dithiocarbamate in coordination. The non‐bonding Zn–S distance is 5.004(3) Å. Copyright © 2004 John Wiley & Sons, Ltd.
Organosilicon(IV) and organotin(IV) complexes as biocides and nematicides: synthetic, spectroscopic and biological studies of N∩N donor sulfonamide imine and its chelates
Authors: Jain Mukta , Gaur Shweta , Singh V. P. , Singh R. V.
Published: January 2004

A brief account is given of the synthesis and stereochemistry and the antibacterial, antifungal, nematicidal and insecticidal behaviour of organosilicon(IV) and organotin(IV) complexes of a biologically potent ligand, 2‐acetylfuransulfaguanidine. The unimolar and bimolar substitution products have been characterized by elemental analyses, conductance measurements, molecular weight determinations, and spectral studies, viz. IR, 1H NMR, 13C NMR, UV, 29Si NMR and 119Sn NMR spectra. The data support the binding of the nitrogen atom to the metal atom in R3M(N∩N), [R2M(N∩N)2 and R2M(N∩N)Cl [(R = Me/Ph and M = Si(IV) and Sn(IV)] types of complex. Based on these studies, with coordination number five and six a trigonal bipyramidal and an octahedral geometry have been proposed for the resulting derivatives. The free ligand (N∩NH) and its respective metal complexes were tested in vitro against a number of microorganisms to assess their antimicrobial properties. The results are indeed positive. In addition to these studies, the complexes also show good nematicidal and insecticidal properties. The results of these findings have been discussed in detail. Copyright © 2004 John Wiley & Sons, Ltd.
Crystallographic report: catena‐Aqua(2,2′‐bipyrimidine)lithium(I) perchlorate
Authors: Tong Ming‐Liang , Hu Sheng , Yu Xiao‐Lan , Chen Xiao‐Ming
Published: January 2004

A lithium(I) coordination polymer has been formed from LiClO4 and the 2,2′‐bipyrimidine (bpym) ligand in which each square pyramidal lithium(I) atom is coordinated in the basal plane by four nitrogen donor atoms derived from two bpym ligands and one water molecule at the apical position. These are connected into a layer structure via hydrogen‐bonding interactions involving the perchlorate anions. Copyright © 2004 John Wiley & Sons, Ltd.
Crystallographic report: A two‐dimensional layer structure containing calcium: [Ca3(1,3,5‐benzenetricarboxylate)2(H2O)12]n
Authors: Yang Yang‐Yi , Huang Zhong‐Qi , Szeto Lap , Wong Wing‐Tak
Published: January 2004

In the crystal structure, an eight‐coordinated calcium center is connected to adjacent seven‐coordinated calcium ions by a pair of µ‐aqua bridging ligands, leading to the formation of a chain, which is linked via benzenetricarboxylate ligands to neighboring chains to furnish a two‐dimensional layer structure. Layers are connected into a three‐dimensional structure facilitated by hydrogen bonding interactions. Copyright © 2004 John Wiley & Sons, Ltd.
Short communication: An alternative and effective catalyst for the silastannation of arylacetylenes with Me3SiSnBu3 at room temperature
Authors: Nakano Taichi , Miyamoto Takashi , Endoh Takanori , Shimotani Makoto , Ashida Naoki , Morioka Toshishige , Takahashi Yutaka
Published: January 2004

The palladium‐catalyzed silastannation of acetylenes with tributyl(trimethylsilyl)stannane in the presence of triethylphosphite is reported for the first time. The reaction occurs at room temperature to give (Z)‐silyl(stannyl)ethenes in high yields. The protodemetallation of the resulting adducts with HCl–tetraethylammonium chloride is described first, which demonstrates that the reaction is governed only by the stability of a carbonium ion arising from the protonation to (Z)‐silyl(stannyl)ethenes rather than the hard and soft acid and base principle, i.e. the β‐cation stabilization effect (σ–π stabilization one) of a stannyl group in the carbonium ion is rather significant. Copyright © 2004 John Wiley & Sons, Ltd.
Crystallographic report: Bis(N,N‐dibenzyldithiocarbamato)mercury(II)
Authors: Lai Chian Sing , Tiekink Edward R. T.
Published: January 2004

The monomeric structure of Hg[S2CN(CH2Ph)2]2, in which the mercury atom lies on a two fold axis that relates the unsymmetrically chelating dithiocarbamate ligands, features a severely distorted tetrahedral geometry. Copyright © 2004 John Wiley & Sons, Ltd.
Crystallographic report: Ethyltriphenyltin(IV), Et(Ph)3Sn
Authors: Casas José S. , Castellano Eduardo E. , Ellena Javier , García‐Tasende María S. , Goméz‐Torres Juán P. , Sánchez Agustín , Sordo José
Published: January 2004

The crystal lattice of the title compound comprises isolated molecules. The coordination polyhedron is a slightly distorted tetrahedron with C–Sn–C bond angles ranging from 106.62(17)° to 113.9(3)°. Copyright © 2004 John Wiley & Sons, Ltd.
Synthesis of Curcumin Analogues as Potential Antioxidant, Cancer Chemopreventive Agents
Authors: Youssef Khairia M. , El‐Sherbeny Magda A. , El‐Shafie Faiza S. , Farag Hassan A. , Al‐Deeb Omar A. , Awadalla Sit Albanat A.
Published: January 2004

New series of 3, 5‐bis(substituted benzylidene)‐4‐piperidones, 2, 7‐bis(substituted benzylidene)cycloheptanones, 1, 5‐bis(substituted phenyl)‐1, 4‐pentadien‐3‐ones, 1, 7‐bis(substituted phenyl)‐1, 6‐heptadien‐3, 5‐diones, 1, 1‐bis(substituted cinnamoyl)‐cyclopentanes, and 1, 1‐bis(substituted cinnamoyl)cyclohexanes have been synthesized and tested for their antioxidant activity. Among the tested compounds, compounds II4, II9 II10, II11, V1, and V4 exhibited higher free radical scavenger activity with % inhibition values of 90.71, 91.24, 96.91, 94.26, 99.23, and 99.85%, respectively. Moreover, compound V1 is the safest member toward peripheral multinuclear neutrophils (PMNs) with a % viability value of 91%. Detailed synthesis, spectroscopic, and biological data are reported.
Synthesis of New Pyrrolo[2, 3‐b]pyridines as a Potent Inhibitor of Tumour Necrosis Factor Alpha
Authors: Hilmy Khalid Mohammed Hassan
Published: January 2004

The MAP kinase p38 plays a key role in the biosynthesis of the inflammatory cytokines tumor necrosis factor α (TNF‐α) and 1L‐1β. Accordingly, new pyrrolo[2, 3‐]pyridine derivatives 5a—d were prepared from 2‐amino‐3‐cyanopyrroles 3a—d via the intermediate propenylaminopyrroles 4a—d. Then the compounds 5a—d were tested for their ability to inhibit the production of TNF‐α in vivo in rats. The most potent compounds 5a and 5b possess enhanced ability to inhibit the production of TNF‐α stimulated with bacterial lipopolysaccharide.
Styrylquinazolines: A New Class of Inhibitors on Prostaglandin E2 Production in Lipopolysaccharide‐activated Macrophage Cells
Authors: Park Jang Hyun , Min Hye‐Young , Kim Sun Suk , Lee Jae Yeol , Lee Sang Kook , Lee Yong Sup
Published: January 2004

A series of styrylquinazoline derivatives (2a—k) were prepared and evaluated for their inhibiton of prostaglandin E2 (PGE2) production by cyclooxygenase‐2 (COX‐2). The latter was induced by lipopolysaccharide‐stimulated macrophage cells RAW264.7.

3′, 4′‐Dihydroxylated styrylquinazolines (2a—c), 3′‐hydroxylated styrylquinazolines (2h, 2i), and 3′‐acetoxy‐styrylquinazolines (2j, 2k) exhibited good inhibitory effects of PGE2 production by COX‐2 with a range of IC50 values of 1.19 ∼ 3.56 μM. The potencies were comparable or better than that of the representative stilbene resveratrol (IC50 = 3.07 μM). These results indicate that styrylquinazolines can be considered as potential resveratrol analogues in the modulation of prostaglandin production by COX‐2.
Synthesis and Antihypertensive Activity of 1‐(2‐Thiazolyl)‐3, 5‐disubstituted ‐2‐Pyrazolines
Authors: Bagheri Maryam , Shekarchi Maryam , Jorjani Masoumeh , Ghahremani Mohammad Hossein , Vosooghi Mohssen , Shafiee Abbas
Published: January 2004

Several substituted 3‐aryl‐1‐(4‐aryl‐2‐thiazolyl)‐5‐(3‐pyridyl)‐2‐pyrazolines were synthesized by reacting substituted 3‐aryl‐5‐(3‐pyridyl)‐1‐thiocarbamoyl‐2‐pyrazolines with phenacyl bromide in ethanol. The structures of all compounds were confirmed by IR, 1H‐NMR, mass spectral data and elemental analyses. The antihypertensive activity of compounds was examined by the tail‐cuff method and compared with clonidine. Compounds 24—28 showed significant antihypertensive activity.
High‐humidity performance of paperboard after treatment with xylanase, endoglucanse, and their combination
Authors: Wong Ken K. Y. , Hamilton Nathan T. , Signal Frances A. , Campion Sylke H.
Published: January 2004

For paperboard used to produce packaging, treatment of its fiber constituents with commercial enzymes can improve its compressive strength under cycling and high‐humidity conditions. Xylanase that selectively removes pulp xylan (ca. 2% of the pulp by mass) yielded most of the observed beneficial effects, which did not appear related to the packing of the fiber network in the sheet or to the uptake of moisture at high humidity. There was also a marginal increase in the drainability of the pulp slurry, which may increase the rate of papermaking. Although endoglucanase activity also enhances certain pulp properties, there was little benefit in adding it to the xylanase treatment. © 2004 Wiley Periodicals, Inc.
Restructuring upstream bioprocessing: technological and economical aspects for production of a generic microbial feedstock from wheat
Authors: Koutinas A. A. , Wang R. , Webb C.
Published: January 2004

Restructuring and optimization of the conventional fermentation industry for fuel and chemical production is necessary to replace petrochemical production routes. Guided by this concept, a novel biorefinery process has been developed as an alternative to conventional upstream processing routes, leading to the production of a generic fermentation feedstock from wheat. The robustness of Aspergillus awamori as enzyme producer is exploited in a continuous fungal fermentation on whole wheat flour. Vital gluten is extracted as an added‐value byproduct by the conventional Martin process from a fraction of the overall wheat used. Enzymatic hydrolysis of gluten‐free flour by the enzyme complex produced by A. awamori during fermentation produces a liquid stream rich in glucose (320 g/L). Autolysis of fungal cells produces a micronutrient‐rich solution similar to yeast extract (1.6 g/L nitrogen, 0.5 g/L phosphorus). The case‐specific combination of these two liquid streams can provide a nutrient‐complete fermentation medium for a spectrum of microbial bioconversions for the production of such chemicals as organic acids, amino acids, bioethanol, glycerol, solvents, and microbial biodegradable plastics. Preliminary economic analysis has shown that the operating cost required to produce the feedstock is dependent on the plant capacity, cereal market price, presence and market value of added‐value byproducts, labor costs, and mode of processing (batch or continuous). Integration of this process in an existing fermentation plant could lead to the production of a generic feedstock at an operating cost lower than the market price of glucose syrup (90% to 99% glucose) in the EU, provided that the plant capacity exceeds 410 m3/day. Further process improvements are also suggested. © 2004 Wiley Periodicals, Inc.
Serial flux mapping of Corynebacterium glutamicum during fed‐batch L‐lysine production using the sensor reactor approach
Authors: Drysch A. , El Massaoudi M. , Wiechert W. , de Graaf A. A. , Takors R.
Published: January 2004

Using our recently developed sensor reactor approach, lysine‐producing, nongrowing Corynebacterium glutamicum MH20‐22B cells were subjected to serial 13C‐labeling experiments for flux analysis during the leucine‐limited fed‐batch production phase in a 300‐L bioreactor. Based on two‐dimensional (2D) nuclear magnetic resonance (NMR) measurements of 13C‐labeling patterns of cytoplasmic free metabolites, metabolic flux distributions in the central metabolism were successfully determined. Focusing on the highly concentrated metabolite L‐glutamate, the working hypothesis was validated that the equilibration of labeling patterns in intracellular pools was much faster (up to 9.45 min) than the labeling period (3 h) used in the experiments. Analysis of anaplerotic reactions revealed that highly selective lysine production was accompanied by a significant reduction of decarboxylating reactions from 10 mol% to only 2 mol%, whereas PEP/pyruvate‐carboxylating fluxes remained constant at about 40 mol% of consumed glucose. These results support the conclusion that an optimized C. glutamicum L‐lysine producer should possess increased PEP carboxylase and/or pyruvate carboxylase activity combined with downregulated, decarboxylating fluxes consuming oxaloacetate/malate. The findings also illustrate the usefulness of the sensor reactor approach in the study of industrial fermentations. © 2004 Wiley Periodicals, Inc.
Effect of doxycycline‐regulated calnexin and calreticulin expression on specific thrombopoietin productivity of recombinant chinese hamster ovary cells
Authors: Chung Joo Young , Lim Seung Wook , Hong Yeon Joo , Hwang Sun Ok , Lee Gyun Min
Published: January 2004

In an attempt to increase the specific thrombopoietin (TPO) productivity (qTPO) of recombinant Chinese hamster ovary (rCHO) cells (CHO‐TPO), the effect of expression level of calnexin (CNX) and calreticulin (CRT) on qTPO was investigated. To control both CNX and CRT expression levels simultaneously, the Tet‐Off system was first introduced in CHO‐TPO cells, and stable Tet‐Off cells (TPO‐Tet‐Off) were screened by luciferase assay. The doxycycline‐regulated CNX and CRT expression system in rCHO cells (TPO‐CNX/CRT) was established by cotransfection of CNX and CRT expression vector and pTK‐Hyg vector into TPO‐Tet‐Off cells and subsequent screening by Western blot analysis of CNX and CRT. The expression levels of CNX and CRT in TPO‐CNX/CRT cells could be tightly controlled by adding different concentrations of doxycycline to a culture medium. Compared with the basal level (2 μg/mL doxycyline), a 2.9‐fold increase in CNX expression and a 2.8‐fold increase in CRT expression were obtained in the absence of doxycycline. This, in turn, resulted in a 1.9‐fold increase in qTPO, not inhibiting cell growth or changing in vivo biological activity of TPO. Taken together, these results demonstrate that a simultaneous overexpression of CNX and CRT can increase the qTPO of rCHO cells. © 2004 Wiley Periodicals, Inc.
Experimental comparison of four methods of end-to-side anastomosis with expanded polytetrafluoroethylene
Authors: Trubel W , Schima H , Czerny M , Perktold K , Schimek M G , Polterauer P
Published: January 2004

Background

Four established techniques of distal end-to-side anastomosis (direct anastomosis, Linton patch, Taylor patch and Miller cuff) were compared to investigate the local distribution of anastomotic intimal hyperplasia. The study aimed to elucidate whether mechanical factors or flow alterations are mainly responsible for the improved patency rates reported for vein cuff interposition techniques in infrainguinal arterial reconstructions using prosthetic graft material.

Methods

Thirty-two expanded polytetrafluoroethylene (ePTFE) femoropopliteal bypass grafts were implanted in 16 sheep using the four anastomotic techniques. After 6 months the grafts were explanted and examined histologically. The local distribution of intimal hyperplasia was determined, particularly for areas of material transition and of high and low shear stress.

Results

The mean amount and distribution of intimal hyperplasia were similar for all anastomotic types. Intimal hyperplasia was greatest along all transitions between ePTFE and venous patches, and between ePTFE and recipient artery. It was lower along the transitions between venous patches and artery, and was lowest at the host artery floor.

Conclusion

Vein interposition did not reduce anastomotic intimal hyperplasia and did not change the distribution patterns of hyperplasia, which were influenced mainly by mechanical factors. The effect of vein interposition is to move areas of maximum intimal hyperplasia away from the small recipient artery up to the more capacious graft-patch anastomosis.
Hyperlipidaemia is positively correlated with lymph node metastasis in men with early gastric cancer
Authors: Kitayama J , Hatano K , Kaisaki S , Suzuki H , Fujii S , Nagawa H
Published: January 2004

Background

Although increased dietary fat or cholesterol has been reported to be a risk factor for the development of certain cancers, the effect of serum lipid levels on tumour metastasis is not clearly understood.

Methods

The association between lymph node metastasis and preoperative serum levels of total cholesterol (TC) and triglyceride (TG) as well as various pathological findings for tumours was examined in 353 patients with early gastric cancer who underwent gastrectomy with classical lymphadenectomy.

Results

The rate of lymph node metastasis was significantly higher in patients with early gastric cancer who had hypercholesterolaemia (TC 220 mg/dl or greater) or hypertriglyceridaemia (TG 150 mg/dl or greater). The tendency was more prominent in men, and multivariate analysis showed that hypertriglyceridaemia was an independent risk factor for nodal metastasis in men, in addition to pathological invasion to the submucosal layer or to lymphatic vessels. In contrast, neither hypercholesterolaemia nor hypertriglyceridaemia showed a significant association with nodal status in women with early gastric cancer.

Conclusion

Raised serum lipid levels might favour the development of lymph node metastasis in men with early-stage gastric cancer. In patients with early gastric cancer serum lipid levels should be checked before operation, and the use of minimal local treatments must be considered carefully in male patients with hyperlipidaemia.
Percutaneous radiofrequency ablation of pulmonary metastases in patients with colorectal cancer
Authors: King J , Glenn D , Clark W , Zhao J , Steinke K , Clingan P , Morris D L
Published: January 2004

Introduction

This study aimed to assess the safety and efficacy of imaging-guided percutaneous radiofrequency ablation (RFA) for local control of lung metastases from colorectal cancer (CRC).

Methods

Twenty patients with lung metastases from CRC were treated with a RITA® Starburst XL electrode and RITA® 1500 generator using temperature control and impedance monitoring. Patients received intravenous sedation and analgesia, or local anaesthetic, and stayed in hospital for at least 24 h after treatment. RFA was assessed with computed tomography (CT) at 1 week and 1 month, and then every 3 months.

Results

Forty-four CRC lung metastases in 19 patients were treated successfully at 25 treatment sessions. Five of 19 patients were retreated for new lesions. There were 13 pneumothoraces following the 25 treatments, and six patients required drainage. The median length of follow-up was 730 (range 148–924) days. Six months after treatment CT demonstrated that three lesions had progressed, 25 metastases were stable or smaller, and 11 were no longer visible. At 12 months five metastases had progressed, 11 were smaller or stable, and nine were not visible.

Conclusion

Percutaneous imaging-guided RFA was associated with modest morbidity. RFA can achieve local control of CRC lung metastases: nine of 25 metastases were not visible on CT at 12 months after treatment.
Mechanism of action of botulinum toxin on the internal anal sphincter
Authors: Jones O M , Brading A F , Mortensen N J McC
Published: January 2004

Background

Botulinum toxin is an effective treatment for anal fissure. Manometric studies support an apparent action of botulinum toxin on the internal anal sphincter (IAS). This aim of this study was to establish the underlying mechanism.

Methods

Porcine IAS strips were suspended in a superfusion organ bath and allowed to equilibrate. Electrical field stimulation (EFS) was applied with parameters that induced nitrergic relaxation followed by noradrenaline-mediated contraction. These responses were compared before and after addition of botulinum toxin.

Results

All strips developed myogenic tone, which was slightly increased following the addition of botulinum toxin. EFS-induced nitrergic relaxation was unaffected by toxin treatment. However, EFS-induced contraction was significantly reduced by toxin treatment. 1,1-Dimethyl-4-phenylpiperazinium iodide (DMPP), a nicotinic agonist, caused muscle strip contraction, which was blocked by guanethidine, implying the presence of sympathetic ganglia within the IAS. Botulinum toxin significantly attenuated DMPP-induced contraction.

Conclusion

In the treatment of anal fissure the major effect of botulinum toxin on the IAS is blockade of sympathetic (noradrenaline mediated) neural output. This is probably a postganglionic action, involving a reduction in noradrenaline release at the neuromuscular junction. Botulinum toxin has no significant effect on nitrergic transmission, which is probably not vesicular in nature.
Differential effect of nitric oxide synthase inhibition on sigmoid colon longitudinal and circular muscle responses to nicotine and nerve stimulation in vitro
Authors: McKirdy H C , Richardson C E , Green J T , Rhodes J , Williams G T , Marshall R W
Published: January 2004

Background

Nicotine has been shown to release nitric oxide from nerves in human sigmoid colon. This effect has been used to investigate the innervation and functional relationship of the longitudinal and circular muscle layers.

Methods

Strips of longitudinal and circular muscle were obtained from 19 patients with colorectal cancer. The strips from ten patients were subjected to electrical field stimulation (EFS) in vitro using stimulus parameters for selective stimulation of nerves. The effect of nicotine 1–10 μmol/l on EFS responses was then measured in the presence and absence of a nitric oxide synthase inhibitor, nitro-l-arginine methyl ester (l-NAME) 200 μmol/l. The effect of nicotine on spontaneous activity was investigated in the muscle strips from the other nine patients.

Results

Both longitudinal and circular strips responded to EFS with contraction. The time to achieve a peak contractile response (time to peak; TTP) was significantly longer (P < 0·001) in circular strips. l-NAME reduced the mean(s.e.m.) TTP in circular muscle from 23·3(2·0) to 17·2(1·5) s (P = 0·007) and altered its pattern of response to resemble that of longitudinal muscle. Nicotine 10 μmol/l reduced the contraction to EFS in circular (P < 0·001) but not in longitudinal (P = 0·347) muscle. The nicotine-induced reduction in circular muscle contraction was blocked by l-NAME 200 μmol/l (P = 0·005).

Conclusion

These findings suggest that nitric oxide release on neural stimulation is greater in circular than in longitudinal muscle.
Population-based study of carotid endarterectomy in Western Australia
Authors: Laurvick C L , Norman P E , Semmens J B , Hobbs M S T
Published: January 2004

Background

Previous studies reported an increase in the rates of operation following the publication of major trials that demonstrated the benefit of carotid endarterectomy in reducing stroke. The aim of this study was to determine whether carotid endarterectomy rates have continued to rise despite the reducing trend in most manifestations of atherosclerotic cardiovascular disease.

Methods

Record linkage was used to select patients who had a carotid endarterectomy during the interval from 1988 to 2001. Incidence rates were age-standardized and trends were examined with Poisson regression.

Results

The rate increased by 13·8 per cent per year between 1988 and 1998; however, from 1999 onwards the rate of carotid surgery fell by 15·8 per cent per year. In octogenarians, the rate increased steadily from 0·9 to 5·1 per 100 000 person-years between 1992 and 2000. The proportion of octogenarians also increased significantly from 0·9 per cent in 1988–1990 to 19·5 per cent in 2000–2001 (χ2 = 60·11, 4 d.f., P < 0·001).

Conclusion

For the first time a recent decline has been observed in the rate of carotid endarterectomy, most likely owing to a combination of the deceasing incidence of atherosclerosis and more widespread use of effective drugs in the treatment of cardiovascular disease. The rate and proportion of operations in patients aged 80 years or older has increased steadily.
Serum vascular endothelial growth factor as a tumour marker in soft tissue sarcoma
Authors: Hayes A J , Mostyn-Jones A , Koban M U , A'Hern R , Burton P , Thomas J M
Published: January 2004

Background

Vascular endothelial growth factor (VEGF) is a potent tumour-produced angiogenic factor. In this study serum levels of VEGF were measured before treatment and during follow-up in patients undergoing primary treatment for suspected soft tissue sarcoma (STS) to assess the value of serum VEGF as a tumour marker.

Methods

Between April 2001 and September 2002, serum VEGF levels were analysed prospectively in 144 patients undergoing primary treatment (surgery, 123; cytotoxic chemotherapy, ten; oral imatinib, eight; radiotherapy, three) for suspected soft tissue sarcoma. Serum VEGF was measured by immunoassay before treatment, in the immediate postoperative interval in patients undergoing surgery, and during follow-up. Serum VEGF concentrations were also measured in 15 healthy volunteers.

Results

Median pretreatment serum VEGF levels were significantly raised in patients with grade 2 and grade 3 sarcomas compared with concentrations in patients with benign lesions (413 and 467 versus 233 pg/ml respectively; P = 0·007 and P = 0·003 respectively). In patients with tumours that had a high level of VEGF expression before treatment, follow-up measurements reflected disease status after treatment.

Conclusion

Serum VEGF expression correlated with grade in soft tissue sarcoma and reflected response to treatment.
Electrolytic liver ablation is not associated with evidence of a systemic inflammatory response syndrome
Authors: Teague B D , Court F G , Morrison C P , Kho M , Wemyss-Holden S A , Maddern G J
Published: January 2004

Background

Local ablation has been proposed for treatment of liver tumours. Cryoshock, a variant of the systemic inflammatory response syndrome (SIRS), is a potentially fatal complication of cryoablation caused by systemic release of necrotic breakdown products from ablated liver. The proinflammatory cytokines tissue necrosis factor (TNF) α and interleukin (IL) 1 are important mediators of this response. This study assessed the risk of SIRS complicating electrolytic liver ablation by measuring circulating levels of inflammatory cytokines, other inflammatory markers and clinical markers of organ function.

Methods

Electrolytic liver ablation was performed in 16 pigs and four pigs served as controls. Platelet count, and serum levels of urea, creatinine, liver enzymes, C-reactive protein (CRP), TNF-α and IL-1β were measured before treatment and for 72 h after the procedure.

Results

There were significant dose-related increases in CRP and alanine aminotransferase levels with liver electrolysis. There was no significant derangement in renal function or platelet count following ablation. A rise in serum TNF-α and IL-1β levels was not associated with liver electrolysis.

Conclusion

There was no evidence of organ failure or significantly raised levels of proinflammatory cytokines as a result of liver electrolysis, suggesting that this is a safe procedure for liver ablation.
The hydroxyl radical scavenger MCI-186 protects the liver from experimental cold ischaemia–reperfusion injury
Authors: Ninomiya M , Shimada M , Harada N , Soejima Y , Suehiro T , Maehara Y
Published: January 2004

Background

Oxidative stress contributes to hepatic ischaemia–reperfusion (IR) injury in a biphasic pattern. In addition to direct cytotoxic effects, oxidative stress also initiates the signal transduction processes that promote second-phase liver injury. The present study investigated the effects of the hydroxyl radical scavenger MCI-186 on the biphasic process of hepatic cold IR injury.

Methods

After cold preservation for 16 h, rat livers were reperfused on an isolated liver perfusion system for 120 min with oxygenated Krebs–Henseleit bicarbonate buffer. Perfusate samples were obtained serially, and portal flow rates were also recorded. To determine whether MCI-186 affected cytokine levels that control the second-phase injury, levels of interleukin (IL) 10 and tumour necrosis factor (TNF) α were measured in the perfusate.

Results

Addition of MCI-186 1 mg/l into the perfusate significantly improved portal flow (P < 0·050), hepatic enzyme release into the perfusate (P = 0·038), total bile production (P = 0·029) and malondialdehyde concentration (P = 0·038). Furthermore, treatment with MCI-186 led to a substantial increase in IL-10 release (P = 0·032). TNF-α levels were not affected.

Conclusions

MCI-186, an agent ready for clinical use, appears to have direct and indirect protective effects against hepatic cold IR injury.
Surgical revision after failure of laparoscopic adjustable gastric banding
Authors: Weiss H G , Kirchmayr W , Klaus A , Bonatti H , Mühlmann G , Nehoda H , Himpens J , Aigner F
Published: January 2004

Background

This paper reports the outcome of surgical revision for complications following laparoscopic placement of an adjustable silicone gastric band (AGB) to treat morbid obesity.

Methods

Seventy-three (19·1 per cent) of 382 patients who underwent laparoscopic AGB placement between January 1996 and March 2001 presented with complications within 6 years after operation. Revision was carried out with the intention of reinstating the functional device in all patients.

Results

Successful surgical revision or gradual balloon deflation was performed in 53 patients (29 port-related complications, 14 pouch dilatations, 12 band leakages, three oesophageal dilatations, two symptomatic hernias, one late migration, one intracerebral bleed). Of these patients, 51 (96·2 per cent) had a successful outcome according to the Bariatric Analysis and Reporting Outcome System following significant additional postinterventional weight loss. AGB removal was carried out in 20 patients (13 early or late migrations, five pouch dilatations, three port-related complications, two psychiatric disorders, one band leakage). The final failure rate for complicated AGB procedures was 30·1 per cent.

Conclusion

AGB placement is associated with a variety of complications. In most cases surgical complications can be treated with minimally invasive surgery, which should allow further weight loss and improvement of quality of life during long-term follow-up. Alternative bariatric procedures should be reserved for patients with poor outcome after surgical revision of the AGB.
Randomized clinical trial of virtual reality simulation for laparoscopic skills training
Authors: Grantcharov T P , Kristiansen V B , Bendix J , Bardram L , Rosenberg J , Funch-Jensen P
Published: January 2004

Background

This study examined the impact of virtual reality (VR) surgical simulation on improvement of psychomotor skills relevant to the performance of laparoscopic cholecystectomy.

Methods

Sixteen surgical trainees performed a laparoscopic cholecystectomy on patients in the operating room (OR). The participants were then randomized to receive VR training (ten repetitions of all six tasks on the Minimally Invasive Surgical Trainer—Virtual Reality (MIST-VR)) or no training. Subsequently, all subjects performed a further laparoscopic cholecystectomy in the OR. Both operative procedures were recorded on videotape, and assessed by two independent and blinded observers using predefined objective criteria. Time to complete the procedure, error score and economy of movement score were assessed during the laparoscopic procedure in the OR.

Results

No differences in baseline variables were found between the two groups. Surgeons who received VR training performed laparoscopic cholecystectomy significantly faster than the control group (P = 0·021). Furthermore, those who had VR training showed significantly greater improvement in error (P = 0·003) and economy of movement (P = 0·003) scores.

Conclusion

Surgeons who received VR simulator training showed significantly greater improvement in performance in the OR than those in the control group. VR surgical simulation is therefore a valid tool for training of laparoscopic psychomotor skills and could be incorporated into surgical training programmes.
Use of oesophagogastroscopy to assess the response of oesophageal carcinoma to neoadjuvant therapy
Authors: Brown W A , Thomas J , Gotley D , Burmeister B H , Lim K-H , Martin I , Walpole E T , Thomson D B , Harvey J A , Smithers B M
Published: January 2004

Background

Approximately 25 per cent of patients with oesophageal cancer who undergo neoadjuvant chemoradiotherapy have no evidence of tumour in the resected specimen (complete pathological response). Those who do not respond have a poor 5-year survival compared with complete responders, regardless of whether or not they undergo surgery. Selecting for surgery only those who have a response to neoadjuvant therapy has the potential to improve overall survival as well as to rationalize the management of non-responders. This study assessed the accuracy of oesophagogastroscopy in this setting.

Methods

A prospective database of 804 patients undergoing oesophageal resection for carcinoma was reviewed. Endoscopic assessment of the response to neoadjuvant therapy in 100 consecutive patients was compared with the pathological assessment of response. The survival for each level of response was compared.

Results

At endoscopy 30 patients were considered to have had a complete response. This was confirmed pathologically in 15 patients. Survival was improved in those with a pathologically confirmed complete response (3-year survival rate 62·4 (s.e. 12·9) per cent) compared with non-responders (16·3 (s.e. 6·6) per cent). Those with microscopic residual disease also had an improved 3-year survival rate (46·3 (s.e. 12·2) per cent); however, oesophagogastroscopy failed to identify this subset.

Conclusion

Oesophagogastroscopy may be useful in the assessment of tumour response to neoadjuvant therapy. However, owing to its poor accuracy patients should not be excluded from further therapeutic intervention on the basis of this assessment alone.
Randomized clinical trial comparing an oral carbohydrate beverage with placebo before laparoscopic cholecystectomy
Authors: Bisgaard T , Kristiansen V B , Hjortsø N C , Jacobsen L S , Rosenberg J , Kehlet H
Published: January 2004

Background

Preoperative oral carbohydrate can attenuate postoperative insulin resistance and catabolism, and may have the potential to improve postoperative recovery. There are no data from randomized studies on postoperative clinical outcome after specific surgical procedures. This study evaluated the clinical effects of a preoperative carbohydrate beverage in patients undergoing laparoscopic cholecystectomy.

Methods

Ninety-four patients undergoing laparoscopic cholecystectomy were included in a randomized clinical trial. Patients were randomized to receive 800 ml of an iso-osmolar 12·5 per cent carbohydrate-rich beverage the evening before operation (100 g carbohydrate) and another 400 ml (50 g carbohydrate) 2 h before initiation of anaesthesia, or the same volume of a placebo beverage. The primary endpoint was general well-being the day after operation. Patients were evaluated from 5 days before to 5 days after operation. Daily scores of general well-being, fatigue, appetite and pain, computerized measurements of physical activity and sleep (actigraphy), and subjective sleep quality were recorded. Nausea and vomiting were assessed twice within the first 24 h after surgery.

Results

Data from 86 patients were available for statistical analysis, 43 in each treatment group. No significant intergroup differences in general well-being or any other outcome variable were found.

Conclusion

A preoperative carbohydrate beverage did not improve clinical outcome after laparoscopic cholecystectomy.
Late complications after ligation and bypass for popliteal aneurysm
Authors: Kirkpatrick U J , McWilliams R G , Martin J , Brennan J A , Gilling-Smith G L , Harris P L
Published: January 2004

Background

Ligation and bypass is standard treatment for popliteal aneurysm. This technique does not abolish collateral circulation to the aneurysm, which may continue to expand and/or rupture. This study assessed whether complete thrombosis of the aneurysm sac occurs after operation and examined the long-term clinical outcome.

Methods

The records of all patients who underwent popliteal aneurysm repair in a university hospital over 10 years were reviewed. Patients who had undergone ligation and bypass were recalled for clinical and ultrasonographic examination to determine the fate of the aneurysm sac.

Results

Persistent blood flow in the aneurysm sac was present in 12 of 36 legs a median of 48 months after operation. This was associated with symptomatic enlargement of the aneurysm in six patients. The incidence of sac enlargement was lower in bypassed aneurysms with no intrasac flow on duplex examination.

Conclusion

Ligation and bypass does not always abolish blood flow in the sac of a popliteal aneurysm. It may be associated with continued expansion and late complications.
Arterioportal shunting as an alternative to microvascular reconstruction after hepatic artery resection
Authors: Kondo S , Hirano S , Ambo Y , Tanaka E , Kubota T , Katoh H
Published: January 2004

Background

Portal vein and hepatic artery resection and reconstruction may be required in radical surgery for biliary cancer. Microvascular reconstruction requires special equipment and training, and may be difficult to accomplish when the arterial stump is small, when there are multiple vessels or when the stump lies deep within the wound. This study examined the feasibility and safety of arterioportal shunting as an alternative to arterial reconstruction.

Methods

Over 30 months, ten patients with biliary cancer (six bile duct and four gallbladder carcinomas) underwent radical surgery with en bloc resection of the hepatic artery and end-to-side arterioportal reconstruction between the common hepatic or gastroduodenal artery and the portal trunk.

Results

No patient died. Complications included bile leakage in two patients and liver abscess in one. Routine angiography performed 1 month after surgery revealed shunt occlusion in three patients. Once the existence of hepatopetal arterial collaterals had been confirmed in the remaining patients, the shunt was occluded by coil embolization.

Conclusion

Arterioportal shunting appears to be a safe alternative to microvascular reconstruction after hepatic artery resection. However, the safety of the procedure and its potential to increase the cure rate require further assessment in a larger series with a longer follow-up.
Liver transplantation for hepatocellular carcinoma
Authors: Lo C-M , Fan S-T
Published: January 2004

Far from being a general solution
Reflux after oesophagectomy
Authors: Aly A , Jamieson G G
Published: January 2004

Background

Reflux of gastric and duodenal content after oesophagectomy with gastric conduit reconstruction is a common problem and largely considered an inevitable consequence of surgery. Cervical burning and regurgitation, often more pronounced when supine, can be troublesome and even disabling, interfering substantially with quality of life. The aim of this study was to identify the factors contributing to reflux after oesophagectomy and evaluate measures to prevent or control it.

Methods

A Medline search using the terms ‘gastro-oesophageal reflux’, ‘oesophagectomy’ and ‘antireflux surgery’ was conducted. Additional references and search pathways were sourced from the bibliographies of articles located.

Results and conclusion

Reflux after oesophagectomy is a significant problem, with both clinical and pathological consequences. Simple measures to facilitate gastric emptying, such as creating a gastric tube, performing a pyloric drainage procedure and using gastric motility agents, may produce a reduction in symptoms but do not alone control reflux itself. A variety of surgical reconstructions have been used, many of which are either difficult to fashion or not suitable when a radical resection has been performed. A modified fundoplication at the anastomosis seems to be the simplest technique and may be relatively effective in controlling symptoms. The impact of strategies to reduce reflux on quality of life and on pathological sequelae of reflux in the oesophageal remnant remains to be evaluated.
Letter 1: Value of endoscopic ultrasonography as a predictor of long-term survival in oesophageal carcinoma (Br J Surg 2003; 90: 1367–1372)
Authors: Park K
Published: January 2004

The Editors welcome topical correspondence from readers relating to articles published in the Journal. Responses can be sent electronically via the BJS website (www.bjs.co.uk) or by post. 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. Letters submitted by post should be typed on A4-sized paper in double spacing and should be accompanied by a disk.
Chimeras of the Homing Endonuclease PI‐SceI and the Homologous Candida tropicalis Intein: A Study to Explore the Possibility of Exchanging DNA‐Binding Modules to Obtain Highly Specific Endonucleases with Altered Specificity
Authors: Steuer Shawn , Pingoud Vera , Pingoud Alfred , Wende Wolfgang
Published: January 2004

Homing endonucleases are extremely specific endodeoxyribonucleases. In vivo, these enzymes confer mobility on their genes by inducing a very specific double‐strand cut in cognate alleles that lack the cooling sequence for the homing endonuclease; the cellular repair of the double‐strand break with the endonuclease‐containing allele as a template leads to integration of the endonuclease gene, completing the homing process. As a result of their extreme sequence specificity, homing endonucleases are promising tools for genome engineering. For this purpose, it is desirable to design enzymes with defined new specificities. To analyse which DNA‐binding elements are potential candidates for use in the design of enzymes with modified or even new specificity, we produced several chimeric proteins derived from the Saccharomyces cerevisiae VMA1 intein (PI‐SceI) and the related Candida tropicalis VMA1 intein. Although the mature Candida intein is devoid of endonucleolytic activity, the exchange of two DNA‐binding modules of PI‐SceI with the homologous elements from the Candida intein results in an active endonuclease. The low sequence homology in these modules indicates that different protein–DNA contacts are responsible for the recognition of related DNA sequences. This flexibility in DNA recognition should, in principle, allow endonucleases to be produced with new specificities useful for genome engineering.
Cover Picture: Consensus Design of Repeat Proteins (ChemBioChem 2/2004)
Authors: Forrer Patrik , Binz H. Kaspar , Stumpp Michael T. , Plückthun Andreas
Published: January 2004

The cover picture shows an illustration of consensus design, a powerful protein‐engineering method that is based on sequence alignments of homologous proteins. An alignment of ankyrin repeats is shown in the sequence plane, and a consensus‐designed ankyrin repeat protein based on this alignment is shown in ribbon representation hovering over the plane. See more about the consensus design of repeat proteins and its use in repeat‐protein library construction in the article by Plückthun et al. on p. 183 ff. Such libraries promise to be excellent sources of a novel type of specific binding molecules. The help of Christian Zahnd in preparing this picture is gratefully acknowledged.
Transformation from Munsell space to Swedish NCS—Through Nayatani theoretical space
Authors: Nayatani Yoshinobu
Published: January 2004

A relationship and a method of transformation are given on color attributes between Munsell, Nayatani Theoretical, and NCS color spaces. The purpose of the study is to clarify the conceptual differences in structure between the three spaces. The structural differences are explained by using the transformations on five color samples. © 2004 Wiley Periodicals, Inc. Col Res Appl, 29, 151–157, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.10235