bluuebunny/crossref_metadata_2025 huggingface dataset:
Complete subunit sequences, structure and evolution of the 6 × 6‐mer hemocyanin from the common house centipede, Scutigera coleoptrata
Authors: Kusche Kristina , Hembach Anne , Hagner‐Holler Silke , Gebauer Wolfgang , Burmester Thorsten
Published: June 2003

Hemocyanins are large oligomeric copper‐containing proteins that serve for the transport of oxygen in many arthropod species. While studied in detail in the Chelicerata and Crustacea, hemocyanins had long been considered unnecessary in the Myriapoda. Here we report the complete molecular structure of the hemocyanin from the common house centipede Scutigera coleoptrata (Myriapoda: Chilopoda), as deduced from 2D‐gel electrophoresis, MALDI‐TOF mass spectrometry, protein and cDNA sequencing, and homology modeling. This is the first myriapod hemocyanin to be fully sequenced, and allows the investigation of hemocyanin structure–function relationship and evolution. S. coleoptrata hemocyanin is a 6 × 6‐mer composed of four distinct subunit types that occur in an approximate 2 : 2 : 1 : 1 ratio and are 49.5–55.5% identical. The cDNA of a fifth, highly diverged, putative hemocyanin was identified that is not included in the native 6 × 6‐mer hemocyanin. Phylogenetic analyses show that myriapod hemocyanins are monophyletic, but at least three distinct subunit types evolved before the separation of the Chilopoda and Diplopoda more than 420 million years ago. In contrast to the situation in the Crustacea and Chelicerata, the substitution rates among the myriapod hemocyanin subunits are highly variable. Phylogenetic analyses do not support a common clade of Myriapoda and Hexapoda, whereas there is evidence in favor of monophyletic Mandibulata.
Characterization of the bioactive conformation of the C‐terminal tripeptide Gly‐Leu‐Met‐NH2 of substance P using [3‐prolinoleucine10]SP analogues
Authors: Quancard Jean , Karoyan Philippe , Sagan Sandrine , Convert Odile , Lavielle Solange , Chassaing Gérard , Lequin Olivier
Published: June 2003

Residue Leu10 of substance P (SP) is critical for NK‐1 receptor recognition and agonist activity. In order to probe the bioactive conformation of this residue, cis‐ and trans‐3‐substituted prolinoleucines were introduced in position 10 of SP. The substituted SP analogues were tested for their affinity to human NK‐1 receptor specific binding sites (NK‐1M and NK‐1m) and their potency to stimulate adenylate cyclase and phospholipase C in CHO cells transfected with the human NK‐1 receptor. [trans‐3‐prolinoleucine10]SP retained affinity and potency similar to SP whereas [cis‐3‐prolinoleucine10]SP shows dramatic loss of affinity and potency. To analyze the structural implications of these biological results, the conformational preferences of the SP analogues were analyzed by NMR spectroscopy and minimum‐energy conformers of Ac‐cis‐3‐prolinoleucine‐NHMe, Ac‐trans‐3‐prolinoleucine‐NHMe and model dipeptides were generated by molecular mechanics calculations. From NMR and modeling studies it can be proposed that residue Leu10 of SP adopts a gauche(+) conformation around the χ1 angle and a trans conformation around the χ2 angle in the bioactive conformation. Together with previously published results, our data indicate that the C‐terminal SP tripeptide should preferentially adopt an extended conformation or a PPII helical structure when bound to the receptor.
Active site mutants of Drosophila melanogaster multisubstrate deoxyribonucleoside kinase
Authors: Solaroli Nicola , Bjerke Mia , Amiri Marjan H. , Johansson Magnus , Karlsson Anna
Published: June 2003

The multisubstrate deoxyribonucleoside kinase of Drosophila melanogaster (Dm‐dNK) is sequence‐related to three human deoxyribonucleoside kinases and to herpes simplex virus type‐1 thymidine kinase. Dm‐dNK phosphorylates both purine and pyrimidine deoxyribonucleosides and nucleoside analogues although it has a preference for pyrimidine nucleosides. We performed site‐directed mutagenesis on residues that, based on structural data, are involved in substrate recognition. The aim was to increase the phosphorylation efficiency of purine nucleoside substrates to create an improved enzyme to be used in suicide gene therapy. A Q81N mutation showed a relative increase in deoxyguanosine phosphorylation compared with the wild‐type enzyme although the efficiency of deoxythymidine phosphorylation was 10‐fold lower for the mutant. In addition to residue Q81 the function of amino acids N28, I29 and F114 was investigated by different substitutions. All of the mutated enzymes showed decreased efficiency of thymidine phosphorylation in comparison with the wild‐type enzyme supporting their importance for substrate binding and/or catalysis as proposed by the recently solved structure of Dm‐dNK.
Molecular characterization of H2O2‐forming NADH oxidases from Archaeoglobus fulgidus
Authors: Kengen Servé W. M. , van der Oost John , Vos Willem M. de
Published: June 2003

Three NADH oxidase encoding genes noxA‐1, noxB‐1 and noxC were cloned from the genome of Archaeoglobus fulgidus, expressed in Escherichia coli, and the gene products were purified and characterized. Expression of noxA‐1 and noxB‐1 resulted in active gene products of the expected size. The noxC gene was expressed as well but the protein produced showed no activity in the standard Nox assay. NoxA‐1 and NoxB‐1 are both FAD‐containing enzymes with subunit molecular masses of 48 and 69 kDa, respectively. NoxA‐1 exists predominantly as homodimer, NoxB‐1 as monomer. NoxA‐1 and NoxB‐1 showed pH optimum of 8.0 and 6.5, with specific NADH oxidase activities of 5.8 U·mg−1 and 4.1 U·mg−1, respectively. Both enzymes were specific for NADH as electron donor, but with different apparent Km values (NoxA‐1, 0.13 mm; NoxB‐1, 0.011 mm). The apparent Km values for oxygen differed significantly (NoxA‐1, 0.06 mm; NoxB‐1, 2.9 mm). In contrast with all mesophilic homologues, both enzymes were found to produce predominantly H2O2 instead of H2O. Despite apparent similarities, NoxB‐1 is essentially different from NoxA‐1. Whereas NoxA‐1 resembles typical H2O‐producing Nox enzymes that are expected to have a role in oxidative stress defence, NoxB‐1 belongs to a small group of enzymes that is involved in catalysing the reduction of unsaturated acids and aldehydes, suggesting a role in fatty acid oxidation. Moreover, NoxB‐1 contains a ferredoxin‐like motif, which is absent in NoxA‐1.
Systematic characterization of mutations in yeast acetohydroxyacid synthase
Authors: Duggleby Ronald G. , Pang Siew Siew , Yu Hongqi , Guddat Luke W.
Published: June 2003

Acetohydroxyacid synthase (AHAS, EC 4.1.3.18) catalyses the first step in branched‐chain amino acid biosynthesis and is the target for sulfonylurea and imidazolinone herbicides, which act as potent and specific inhibitors. Mutants of the enzyme have been identified that are resistant to particular herbicides. However, the selectivity of these mutants towards various sulfonylureas and imidazolinones has not been determined systematically. Now that the structure of the yeast enzyme is known, both in the absence and presence of a bound herbicide, a detailed understanding of the molecular interactions between the enzyme and its inhibitors becomes possible. Here we construct 10 active mutants of yeast AHAS, purify the enzymes and determine their sensitivity to six sulfonylureas and three imidazolinones. An additional three active mutants were constructed with a view to increasing imidazolinone sensitivity. These three variants were purified and tested for their sensitivity to the imidazolinones only. Substantial differences are observed in the sensitivity of the 13 mutants to the various inhibitors and these differences are interpreted in terms of the structure of the herbicide‐binding site on the enzyme.
Ligand‐specific dose–response of heterologously expressed olfactory receptors
Authors: Levasseur Grégoire , Persuy Marie‐Annick , Grebert Denise , Remy Jean‐Jacques , Salesse Roland , Pajot‐Augy Edith
Published: June 2003

Primary olfactory neuronal cultures exposed to odorant stimulation have previously exhibited concentration‐related effects in terms of intracellular cAMP levels and adenylate cyclase activity [Ronnett, G.V., Parfitt, D.J., Hester, L.D. & Snyder, S.H. (1991) PNAS88, 2366–2369]. Maximal stimulation occurred for intermediate concentrations, whereas AC activity declined for both low and high odorant concentrations. We suspected that this behavior might be ascribed to the intrinsic response of the first molecular species concerned by odorant detection, i.e. the olfactory receptor itself. In order to check this hypothesis, we developed an heterologous expression system in mammalian cells to characterize the functional response of receptors to odorants. Two mammalian olfactory receptors were used to initiate the study, the rat I7 olfactory receptor and the human OR17‐40 olfactory receptor. The cellular response of transfected cells to an odorant stimulation was tested by a spectrofluorimetric intracellular calcium assay, and proved in all cases to be dose‐dependent for the known ligands of these receptors, with an optimal response for intermediate concentrations. Further experiments were carried out with the rat I7 olfactory receptor, for which the sensitivity to an odorant, indicated by the concentration yielding the optimal calcium response, depended on the carbon chain length of the aldehydic odorant. The response is thus both ligand‐specific and dose‐dependent. We thus demonstrate that a differential dose–response originates from the olfactory receptor itself, which is thus capable of efficient discrimination between closely related agonists.
Exo‐mode of action of cellobiohydrolase Cel48C from Paenibacillus sp. BP‐23
Authors: Sánchez Marta M. , Pastor F. I. Javier , Diaz Pilar
Published: June 2003

Sequence analysis of a Paenibacillus sp. BP‐23 recombinant clone coding for a previously described endoglucanase revealed the presence of an additional truncated ORF with homology to family 48 glycosyl hydrolases. The corresponding 3509‐bp DNA fragment was isolated after gene walking and cloned in Escherichia coli Xl1‐Blue for expression and purification. The encoded enzyme, a cellulase of 1091 amino acids with a deduced molecular mass of 118 kDa and a pI of 4.85, displayed a multidomain organization bearing a canonical family 48 catalytic domain, a bacterial type 3a cellulose‐binding module, and a putative fibronectin‐III domain. The cloned cellulase, unique among Bacillales and designated Cel48C, was purified through affinity chromatography using its ability to bind Avicel. Maximum activity was achieved at 45 °C and pH 6.0 on acid‐swollen cellulose, bacterial microcrystalline cellulose, Avicel and cellodextrins, whereas no activity was found on carboxy methyl cellulose, cellobiose, cellotriose, pNP‐glycosides or 4‐methylumbeliferyl α‐d‐glucoside. Cellobiose was the major product of cellulose hydrolysis, identifying Cel48C as a processive cellobiohydrolase. Although no chromogenic activity was detected from pNP‐glycosides, TLC analysis revealed the release of p‐nitrophenyl‐glycosides and cellodextrins from these substrates, suggesting that Cel48C acts from the reducing ends of the sugar chain. Presence of such a cellobiohydrolase in Paenibacillus sp. BP‐23 would contribute to widen up its range of action on natural cellulosic substrates.
Fracture care of friend and foe during World War I
Authors: Kirkup John
Published: June 2003

Background:  In the early years of trench warfare, compound lower limb fractures caused by gunshot missiles prompted the ­questioning of traditional splintage techniques and established evacuation methods. These prejudiced recovery and delayed surgery, often by many days, causing a high mortality rate especially for open femoral fractures. Importantly, battle weaponry was modified by differences in climate and terrain in Mesopotamia, Gallipoli, the Alps and the Northern European plain, to manifest differences in wound pathology. In Flanders, the static situation limited simple bullet wounds and launched a high percentage of jagged shell ­fragment injuries complicated by tissue destruction, in‐driven clothing and metal contaminated with mud, lethal bacteria and spores. From no‐mans‐land, soldiers with arm fractures scrambled back unaided, with tibial fractures they might hobble between two comrades, but with femoral fractures they were helpless unless stretcher bearers arrived. Often they did not, or only after a lull in fighting, by which time death from blood loss or exposure supervened. Even on a stretcher, poor fracture immobilization and long arduous carries added to shock and mortality. Remedies to these deficiencies and observations by Australasian, Austrian, British, Canadian, French, German, South African and American surgeons are noted.

Conclusions:  Trained to treat bullet wounds in open terrain, many military medical organizations were slow to adjust to the novel challenges associated with trench warfare. However, from 1917 well‐trained stretcher bearers, efficient application of the Thomas splint, better control of haemorrhage and more rapid evacuation with motorized ambulances reduced deaths, amputation rates and long‐term disability significantly.
Effects of heterotopic bone formation on outcome after hip arthroplasty
Authors: Neal Bruce
Published: June 2003

Background:  Heterotopic bone formation (HBF) is well established as a frequent complication of major hip surgery, but its importance as a cause of impaired postoperative outcome is uncertain.

Methods:  A systematic overview of all studies that reported the association of HBF with the risk of impaired range of movement, pain or poor function, late after hip arthroplasty.

Results:  A computer‐based search identified 37 relevant studies that included 10 826 individuals. There were 30 studies (8305 participants) that assessed the association between HBF and range of movement, 14 studies (7420 participants) that assessed the association between HBF and pain and 16 studies (5918 participants) that assessed the association between HBF and function. Overall, there was a clear positive association of HBF with the risk of an impaired range of movement at the hip joint and with the risk of a poor functional outcome. The association of HBF with pain was unclear. There was evidence of effects of mild‐to‐moderate HBF on the postoperative range of movement.

Conclusions:  These results suggest that mild‐to‐moderate HBF, not just severe HBF, can influence outcome after major hip ­surgery. HBF may therefore be a more frequent cause of postoperative symptomatology than is generally believed. It is possible that effective prophylactic regimens will improve outcomes in large numbers of patients.
Nasal fractures: a study comparing local and general anaesthesia techniques
Authors: Rajapakse Yosanta , Courtney Mark , Bialostocki Adam , Duncan Gary , Morrissey Graham
Published: June 2003

Background:  The objective of the present study was to examine the outcome of nasal fracture reduction under both local anaesthesia and general anaesthesia techniques.

Methods:  Patient records were obtained from clinic lists of patients attending the otolaryngology (ORL) outpatient unit at ­Wellington Hospital or the plastic surgical unit at Hutt Hospital over a 24‐month period. To meet criteria for inclusion, patients had to have an isolated nasal deformity, be aged 14 years or older and be at least 6 months post reduction. Functional and aesthetic results were assessed using subjective and objective end outcome measures. A questionnaire was developed and used to assess subjective outcomes. The number of patients proceeding to open operative correction was used for the objective measure, which included septoplasty, septorhinoplasty or rhinoplasty.

Results:  A total of 197 patients had nasal fractures manipulated over this period. One hundred and seven were manipulated under general anaesthesia (GA) and 90 were manipulated under local anaesthesia (LA). The questionnaire completion rate was 66%. Patient demographics were statistically similar between the two groups. There was no statistical difference in patients" subjective assessment of outcome with treatment by GA or LA. More patients preferred to have their fracture manipulated under GA but this was not ­statistically significant. There was no significant difference between GA and LA groups in progression to open operative correction.

Conclusions:  Both LA and GA appear to be acceptable and satisfactory methods of anaesthesia in the reduction of simple displaced nasal fracture.
Single institution's initial experience with sentinel lymph node biopsy in breast cancer patients
Authors: Yong W. S. , Wong C. Y. , Lee J. S. Y. , Soo K. C. , Tan P. H. , Goh A. S. W.
Published: June 2003

Background:  The sentinel lymph node is the first draining node from a cancer‐bearing area and is therefore the first to manifest metastasis. In breast cancer it has been shown to predict the axillary status. Axillary dissection provides information determining prognosis and need for adjuvant therapy but carries a certain morbidity. Our aim was to determine the feasibility of detecting the sentinel node in a teaching hospital and whether the sentinel node accurately predicts the axillary status.

Methods:  All patients with stage I and II breast cancer and non‐palpable axillary nodes were eligible, including those with previous excision biopsy. We excluded pregnant women, those with previous axillary surgery and women with advanced breast cancer with enlarged axillary nodes. The sentinel node was detected with technetium‐99m‐labelled tin colloid and vital blue dye and removed, and axillary clearance was performed.

Results:  A total of 312 patients were examined from August 1996 to December 1998. The mean age was 53 years (range 28−83) and mean tumour size 2.6 cm (range 0.2−9.0). The detection rate of the sentinel node was 86%. The sentinel lymph node predicted the axillary status with a sensitivity of 83% and specificity of 100%. The false‐negative rate was 16.7%.

Conclusions:  Detection of the sentinel lymph node is feasible and it can accurately predict the nodal status of the axilla. ­However, the high false‐negative rate precludes as yet the use of sentinel lymph node biopsy in replacing axillary clearance as the standard of care for breast cancer.
Anatomical justification of Belghiti's ‘liver hanging manoeuvre’ in right hepatectomy with anterior approach
Authors: Meng William C.S. , Shao C.X. , Mak K.L. , Lau Patrick Y.Y. , Yeung Y.P. , Yip Andrew W.C.
Published: June 2003

Background:  In cases of right hepatectomy for huge tumour encroaching onto the diaphragm, the ‘anterior approach’ is the most common surgical procedure undertaken. The ‘liver hanging manoeuvre’ has been described previously as an adjunct to this pro­cedure. It involves the dissection of a retrohepatic avascular plane anterior to the surface of the inferior vena cava. A tape is then passed through and the liver is resected under suspension.

Methods:  Cadaveric specimens were used to identify the structural relationship of the avascular plane and also to determine whether it is truly avascular.

Results:  Thirteen cases were analysed. The mean length of the avascular tunnel was 6.4 ± 1.0 cm. The median number of accessory hepatic veins within the tunnel was two (zero to three). At the caudal half of the tunnel, the median number of veins was two (zero to three). As for the cranial half of the tunnel, there were two cases with one vein in each.

Conclusions:  The key to the liver hanging manoeuvre is to develop the retrohepatic tunnel. However, our study showed that it is not absolutely avascular. During the blind dissection, there is a chance of damaging a retrohepatic vein. This may result in troublesome haemorrhage within the confines of the tunnel. Video‐assisted dissection of this region may help in visualisation, and hence control, in order to avoid bleeding.
Solid pseudopapillary tumour of the pancreas
Authors: Ng Kheng Hong , Tan Puay Hoon , Thng Choon Hua , Ooi London Lucien
Published: June 2003

Background:  Solid pseudopapillary tumour of the pancreas is a rare pancreatic tumour that occurs predominantly in women, with very few cases reported in men. This is a tumour with low malignancy potential and surgical resection usually results in cure.

Methods:  A retrospective review of our experience with solid pseudopapillary tumours between April 1992 and December 2000 was undertaken.

Results:  Six patients were identified including one male patient. The median age was 30 years, with four patients presenting with abdominal pain and discomfort and two patients presenting with palpable abdominal masses. The mean tumour diameter was 10.2 cm and the lesions were found mainly in the body and tail of the pancreas. Only one patient had tumour at the pancreatic head. One patient had a locally invasive disease and another had peritoneal spread. None of the patients received adjuvant therapy. The mean follow up was 3.8 years (range: 1.5−10.0) and all patients were free of recurrence to date.

Conclusion:  SPT is a rare tumour with an unclear origin that has a distinct histology and presentation. Although preoperative diagnosis is difficult by computed tomography, magnetic resonance imaging may potentially improve this situation. In general, this is a tumour of very low malignant potential and long‐term survival is excellent after resection of the tumour.
Writings of Daniel Turner and his views on the practice of surgery
Authors: Magee Reginald
Published: June 2003

In the Cowlishaw collection there are two publications by Daniel Turner (1667−1740). These are his Apologia Chyrurgica and an epistle to Dr James Jurin. Turner qualified first as a surgeon and later practised as a physician. He was a successful author and it has been said that ‘His cases are not stated in the most delicate terms, nor was politeness among his excellencies’. Both of these publications were very critical of the various pretenders who engaged in medical practice at that time. A review of these works has been carried out and consideration of the type of practice in which these people were engaged.
Sir Thomas Browne: physician 1605−1682 and the Religio Medici
Authors: Mellick Sam
Published: June 2003

Sir Thomas Browne, 1605−1682, a physician of great scholarship, published his Religio Medici in 1642 as an expression of his own religious and professional beliefs. He had studied in Oxford and then turned to medicine and he pursued these studies in the Uni­versities of Montpellier, Padua and Leiden in Europe. Returning to Britain, he completed his medical degree and practised in Norwich for over three decades. He was considered one of the foremost physicians in England, although he did not practise in London, and he was conscious of the need for doctors to have a good knowledge of anatomy at a time when, before anaesthesia, surgery was becoming more adventurous. He was knighted by King Charles II in 1671. The curtailment of anatomy teaching in many undergraduate and postgraduate schools of medicine today would not have appealed to Browne. It is of growing concern to surgical colleges and academies who are now required to provide additional postgraduate anatomy teaching in order to satisfy the requirements of their examinations for surgeons.
An economic perspective on evidence‐based patient choice in surgery
Authors: Salkeld Glenn , Solomon Michael J.
Published: June 2003

The aim of the present paper is to provide an economic perspective on current and emerging issues relating to surgical decision‐making. The central issue discussed in the paper is choice and how this relates to patient management. The paper explores three factors that may influence the nature of choice; they are − evidence‐based medicine, patient involvement in making choices and the role of cost‐effectiveness analysis in surgery. Together, these factors are driving a shift from the traditional model of care based on medical beneficence to one based more on individual patient autonomy. This shift has been described as a move towards ‘evidence‐based patient choice’ (EBPC). The concept of EBPC is relatively new and ill defined. Yet it encapsulates what is happening now and what will occur more dramatically in the future; that is, the nature of the relationship between surgeon and patient is changing. We hope that this paper will provoke discussion on the concept of EBPC and cost‐effectiveness analysis in surgical decision‐making.
Sir William Turner and his studies on the mammalian placenta
Authors: Magee Reginald
Published: June 2003

William Turner was appointed Professor of Anatomy at the University of Edinburgh in 1867, and from 1903 until his death in 1916, he was Principal and Vice‐Chancellor. He was an outstanding teacher and many of those he taught went on to occupy chairs of anatomy. He published widely on anatomical subjects and one of his interests was comparative anatomy and physiology of the placenta.

This paper takes a brief look at Turner's studies on the anatomical structure of the placenta, its comparative anatomy, his thoughts about its physiology and its place in the evolutionary process. At the time, these lectures constituted an anatomical and physiological classic.

At the time Turner prepared his lectures, which were delivered in 1875 and 1876, little was known about the gestatory process in marsupials or monotremes. These mammals have a very brief period of intrauterine gestation and placentation and mention is made of studies that have been done in recent times on this subject.
Surgical repair of spontaneous renal allograft rupture: a new procedure
Authors: He Bulang , Rao M. Mohan , Han Xiuwu , Li Xiaobei , Guan Delin , Gao Juzhong
Published: June 2003

Background: The purpose of the present paper is to introduce a new surgical procedure using the external oblique aponeurosis (EOA) for repair of spontaneous renal allograft rupture.

Methods: Thirty‐eight cases with spontaneous renal allograft rupture were encountered in 1000 consecutive kidney transplants between April 1991 and August 2000. Thirty‐three cases underwent surgical exploration with two grafts undergoing nephrectomy, while a further 31 were repaired using the new surgical procedure. The external oblique aponeurosis (EOA) from the incision was trimmed into 1 cm × 1 cm square pieces. A 2/0 Dexon suture was placed through each piece of the EOA, then through the parenchyma of the kidney perpendicular to the rupture. Each suture was then placed through another piece of EOA and tied.

Results: Two repaired grafts were removed on day 7 and day 10, one due to graft re‐rupture and another with ischaemia secondary to irreversible acute rejection. The graft function of 29 cases had recovered completely at 30 days following surgical repair with one graft improving rapidly. Thirteen grafts were diagnosed as undergoing mild to moderate acute rejection, whereas a further 20 cases were considered to have acute tubular necrosis on histopathology. The allograft survival rate at 1 year and 5 years post grafting was 86% and 64%, respectively. No patients died from postoperative complications following repair using this procedure.

Conclusions: Spontaneous renal allograft rupture is a relatively common post‐transplant complication secondary to either acute tubular necrosis or acute rejection. This new surgical procedure is proposed as a reliable and practical method of repair following graft rupture. Preservation of graft function and viability following rupture appears achievable both in the medium and long‐term.
Outcomes of emergency common bile duct exploration: impact of preoperative endoscopic decompression
Authors: Koh Joyce S. B. , Chow Pierce K. H. , F. Chung Alexander Y. , Ooi Lucien P. J. , Wong Wai‐Keong , Fook‐Chong Stephanie , Soo Khee‐Chee
Published: June 2003

Background:  Emergency common bile duct exploration (CBDE) is still required in patients acutely ill with complicated biliary tract stone disease when endoscopic decompression fails to reverse their condition. This study looks at the clinical profile of patients requiring emergency CBDE and examines the various factors influencing the postoperative outcome.

Methods:  Clinical records of patients with emergency CBDE in Singapore General Hospital from January 1991 to December 1998 were reviewed. Factors influencing postoperative outcomes, for example, pre‐existing medical problems, hepatic para­‐­m­eters, the impact of endoscopic procedures (if any) and indications for surgery, were correlated with postoperative morbidity and 30‐day mortality.

Results:  The records of 100 patients were available for review. Major indications for emergency CBDE were cholangitis (51%) and intraoperative findings of common bile duct obstruction during emergency laparotomy (23%). Six patients had emergency CBDE because of iatrogenic complication of attempted therapeutic endoscopic retrograde cholangiopancreaticography (ERCP) for biliary stones. Overall mortality was 14.0% and 8.0% had retained stones. Mortality was significantly influenced by age, prior biliary disease, preoperative endoscopic biliary decompression in acute cholangitis (33.3%vs 9.4%, P = 0.035) and endoscopic complications.

Conclusions:  Among patients requiring emergency CBDE, uncomplicated preoperative endoscopic biliary decompression ben­efits patients with acute cholangitis.
Major trauma transfer in Western Australia
Authors: Gupta Robin , Rao Sudhakar
Published: June 2003

Background:  The transfer of critically injured patients in a rural Australian setting presents a unique challenge to medical services due to the constraints of distance and time. The purpose of this study is to analyse which injuries are being transferred, how they occur, pretransfer intervention, transfer methods and transfer times.

Methods:  The Trauma Registry Database collected data prospectively on all major rural trauma cases attending the Royal Perth Hospital between August 1994 and January 2000. Patients were divided into rural and metropolitan groups on the basis of trauma location, and the latter group used as a control.

Results:  A total of 1275 major trauma patients were treated of which 566 (44%) were from rural areas. Driver road traffic trauma was the most common cause of injury throughout, although most prominent in rural areas (30%vs 18%). For rural patients, the Royal Flying Doctor Service was responsible for 440 (79%) of transfers of which 83% had a doctor and a nurse escort. The most commonly transferred injuries from rural areas were head injury (63%) and thoracic injury (55%). A total of 450 (93%) rural patients were transferred to Royal Perth Hospital within 24 h of trauma although the mean transfer time was over 9 h.

Conclusions:  This data produces a realistic framework of how major trauma in rural areas is treated in Western Australia. It highlights some areas of good practice, such as transfer methods and escorts, but also highlights problem areas such as transfer times and pretransfer intervention.
Single stage primary anastomosis without colonic lavage for left‐sided colonic obstruction due to acute sigmoid volvulus: a prospective study of one hundred and ninety‐seven cases
Authors: De Utpal , Ghosh Shibajyoti
Published: June 2003

Background:  The purpose of this study was to examine the feasibility of single‐stage resection and anastomosis for acute left‐sided colonic obstruction due to acute sigmoid volvulus without intraoperative lavage. Mechanical bowel preparation has been shown to be unnecessary for elective colorectal surgery. Colonic decompression without intraoperative lavage may simplify operations in acute left‐sided colorectal obstruction.

Methods:  Emergency resection of acute sigmoid volvulus was performed. This was followed by primary anastomosis without on‐table lavage after closed bowel decompression.

Results:  A total of 197 patients underwent bowel decompression, resection and primary colonic anastomosis. Two patients developed anastomosis leak, requiring re‐laparotomy, Hartmann's procedure and delayed closure. Two deaths occurred postoperatively; these were unrelated to the nature of the surgery. The mean hospital stay was 9.8 days.

Conclusion:  Primary colonic anastomosis can be safely done for obstructed left colon due to acute sigmoid volvulus without intraoperative colonic lavage.
Outcome after intramedullary nailing of femoral shaft fractures
Authors: Harris Ian , Hatfield Angela , Donald Geoff , Walton Judie
Published: June 2003

Background:  The results of intramedullary nailing of femoral shaft fractures from Australian institutions have not been widely reported. This study examines a consecutive group of patients treated at a major metropolitan trauma centre and reports on the injury statistics and outcome data, and compares this to previously reported results from the literature.

Methods:  A total of 101 fractures in 97 consecutive adult patients were included in the study. Nine patients were excluded. At a minimum of 6 months post injury, 54 patients were interviewed by telephone and 35 patients presented for clinical review and underwent physical examination, computed tomography (CT) scanogram of the lower limbs and Short Form 36 questionnaires.

Results:  Road trauma accounted for 81% of injuries and 15% of fractures were open. Of the 54 patients reviewed, 13 (23%) required further surgery for delayed or non‐union. Of the 35 who presented for physical examination, there was poor correlation between perceived leg length discrepancy and measured leg length discrepancy on examination or scanogram. Presence of a limp correlated with measured leg length discrepancy of more than 1 cm but did not correlate with rotational abnormality measured on CT scanogram. Pain at the hip, thigh or knee was present in 60% of patients. The Short Form 36 scores for physical functioning, role − physical, bodily pain, general health and vitality were all significantly lower than population norms with P values ranging from <0.001−0.05. Subgroup analysis comparing isolated femur fracture to multi‐trauma patients for all five of these parameters revealed significant differences only in the multi‐trauma group.

Conclusion:  The incidence of pain, limp, leg length discrepancy and delayed or non‐union is higher in this study than in previously reported results of intramedullary nailing for femoral shaft fractures. This may be due to differences in the patient population, the skill level of the operating surgeon, or incomplete follow up.
Impact of core biopsy on the management of screen‐detected ductal carcinoma in situ of the breast
Authors: Cheng Michael S. P. , Fox Jane , Hart Stewart A.
Published: June 2003

Background:  Screen‐detected ductal carcinoma in situ (DCIS) usually presents as clinically impalpable microcalcification. Although core biopsy is well established as a diagnostic modality for invasive breast cancers, few reports address its impact on the management of screen‐detected DCIS. We examined the sensitivity of core biopsy in diagnosing screen‐detected DCIS, as well as its role in facilitating one‐step surgery in the community, especially a breast‐conserving approach.

Methods:  Through the Monash BreastScreen database, we reviewed the management of 148 patients diagnosed with pure DCIS over a 4‐year period. Particular attention was paid to the sensitivity and surgical margin status of 63 patients who underwent initial assessment with core biopsy, compared to patients who underwent excisional biopsy or fine needle aspiration cytology (FNAC).

Results:  Core specimens in 63 patients yielded positive histology in 57 (90%), allowing for breast‐conserving surgery in 45 and mastectomy in 12. Negative margins were obtained in 73% of those treated by breast‐conserving surgery, compared to 51% negative margins among those who underwent excisional biopsy initially. Overall, 45 of 57 patients with a positive core biopsy histology (79%) underwent one‐step surgery. Those assessed by FNAC had a 48% incidence of non‐diagnostic/benign cytology.

Conclusions:  Core biopsy facilitates one‐step surgery for screen‐detected DCIS, and potentially reduces the number of surgical procedures. Stereotactic core biopsy for suspicious microcalcifications should replace hookwire‐guided excisional biopsy and FNAC as the diagnostic modality of choice.
Epidemiology of abdominal aortic aneurysm in an Asian population
Authors: Yii Ming Kon
Published: June 2003

Background:  Abdominal aortic aneurysms (AAA) are common in the Caucasian population. Apart from reported differences in the occurrence of AAA in the black and white populations, there are few studies on the incidence of AAA in the Asian population.

Methods:  A prospective database of all patients with AAA seen between 1996 and 1999, in the South‐East Asian state of Sarawak in Borneo Island, was analysed. The demographic data included patient's age, sex, ethnic group, date of diagnosis, comorbidities, presentations and treatment outcomes. These were compared with the state population's demographic statistics.

Results:  Diagnoses of AAA were made in 123 patients during the study period. The male to female ratio was 3.5 : 1. The age range was 39−88 years with a median age of 70 years. Four patients were younger than 55 years. The incidence rate for the at‐risk male population older than 50 years was 25.6/100 000. The incidence rate reached 78.3/100 000 for males older than 70 years. The incidence rate for females older than 50 years was 7.6/100 000 and for those older than 70 years it was 18.7/100 000. All races were affected. Smoking, hypertension or respiratory disorders were present in more than 40% of the patients. Half of the patients underwent surgical repair.

Conclusion:  This study shows that AAA in this Asian population is not uncommon and the incidence is comparable to the Western world.
Thrombotic complications of venous aneurysms
Authors: French James R. , Moncrieff Nicholas J. , Englund Raymond , Hanel Kevin C.
Published: June 2003

Background:  Venous aneurysms are rare vascular anomalies that have been reported to occur throughout the body. We report a unique variation, namely a thrombosed subclavian vein aneurysm.

Methods:  A review of the records of patients with documented venous aneurysms presenting to the St George Hospital and their associated imaging was made. A literature search for articles pertaining to venous aneurysms was performed.

Results:  Four cases of venous aneurysms were identified; one subclavian vein, one inferior vena cava and two popliteal. The clinical course of these cases is detailed, along with a review of the literature.

Conclusions:  Venous aneurysms are infrequent findings and indicate that the patient is at significant risk of thrombosis. Popliteal vein aneurysms should be treated surgically.
A fatigue damage map for 2024‐T3 aluminium alloy
Authors: RODOPOULOS C. A. , DE LOS RIOS E. R. , LEVERS A. , YATES J. R.
Published: June 2003

The propagation of a fatigue crack from an initial defect of the same order as the scale of the microstructure through to failure has been modelled using a representation of fatigue damage according to the Navarro–de los Rios (N–R) model. The fatigue processes are presented in the form of a fatigue damage map (FDM). It is shown how the map can be used to create a traditional S–N curve and to provide information suitable for estimating fatigue lifetimes under damage tolerant conditions.
The effect of plasticity on incipient mixed‐mode fatigue crack growth
Authors: DAHLIN P. , OLSSON M.
Published: June 2003

Several criteria for the prediction of incipient crack path direction of non‐proportional mixed‐mode fatigue cracks, immediately after a change of load from steady mode I conditions are investigated. The analysis is based on two‐dimensional plane strain FE‐simulations in which the actual elasto‐plastic stress distribution is used for the MTS, MTSR and MEPSR criteria. The purpose of the analysis is to compare the numerical results with experimental results as well as with previous predictions based on solely elastic stress analyses, taken from the literature. It is shown that the influence from elasto‐plastic deformation on crack branching direction is of utmost importance. It is found that the incipient crack growth of metals falls into two categories: high strength metals follow the MTSp criterion whereas more ductile metals follow the MTSRp criterion. The subscript p indicates that the elasto‐plastic evaluation of the respective criterion should be used.
Inclined standing contact fatigue
Authors: ALFREDSSON B. , OLSSON M.
Published: June 2003

An experimental method is presented, in which a sphere is repeatedly pressed against a surface with an inclined contact load. The method is a development of the normally loaded standing contact fatigue test. Experiments are performed for three inclination angles below the angle of friction and the results are compared to those of the normally loaded standing contact fatigue test. The influence of tangential load on endurance limit load, number of cycles to crack initiation, contact mark appearance and crack behaviour in the surface as well as in cut views are evaluated. The surface crack behaviour outside the contact mark is analysed based on the cyclic contact stresses in the test specimen. The trajectories of the largest principal stresses are followed in both the surface view and in the cut view on the symmetry plane. These stress trajectories are compared to the experimental crack results. The connection between the inclined standing contact fatigue cracks and surface distress micro‐cracks is also discussed.
A threshold fatigue crack closure model: Part II – experimental verification
Authors: NEWMAN J. A. , RIDDELL W. T. , PIASCIK R. S.
Published: June 2003

Predictions from an analytical model that considers contributions and interactions between plasticity, roughness, and oxide induced crack closure are presented and compared with experimental data. The analytical model is shown to correctly predict the combined influences of crack roughness, oxide debris, and plasticity in the near‐threshold regime. Furthermore, analytical results indicate closure mechanisms interact in a non‐linear manner such that the total amount of closure is not the sum of closure contributions for each mechanism.
Finite element simulation of the mechanics of flat contact pad fretting fatigue tests
Authors: HAMMOUDA M. M. I. , EL‐BATANONY I. G. , SALLAM H. E. M.
Published: June 2003

An understanding into the macro kinetic and kinematic behaviour of fretted surfaces is provided. Making use of a modified version of a previously developed in‐house two‐dimensional elastic–plastic finite element analysis numerically simulates flat contact pad fretting fatigue tests. Basic macro mechanics concepts are adopted to idealise two bodies with rough contact surfaces and loaded at two different sites with arbitrary axial loading profiles. A time scale factor is devised to recognise the earliest candidate out of the events possibly accommodated at each loading increment.

The present analysis utilises a relevant experimental set up developed in the Structural Integrity Research Institute of the University of Sheffield as an application. Computational results accurate to within 1.2% and corresponding to one contact pad span and six constant normal loads acting individually with four amplitudes of two sinusoidal axial load cycles are presented. The present computations include (1) the development of the global and local normal and tangential reactions and relative sliding displacement acting along the fretting surfaces and (2) contact pad deformation, generated stress fields and plasticity development within the neighbouring region of the fretted area.
A threshold fatigue crack closure model: Part I – model development
Authors: NEWMAN J. A. , RIDDELL W. T. , PIASCIK R. S.
Published: June 2003

A fatigue crack closure model is developed that includes the effects of, and interactions between, the three closure mechanisms most likely to occur at threshold; plasticity, roughness, and oxide. This model, herein referred to as the CROP model (for Closure, Roughness, Oxide, and Plasticity), also includes the effects of out‐of‐plane cracking and multi‐axial loading. These features make the CROP closure model uniquely suited for, but not limited to, threshold applications. Rough cracks are idealized here as two‐dimensional sawtooths, whose geometry induces mixed‐mode crack‐tip stresses. Continuum mechanics and crack‐tip dislocation concepts are combined to relate crack face displacements to crack‐tip loads. Geometric criteria are used to determine closure loads from crack‐face displacements. Finite element results, used to verify model predictions, provide critical information about the locations where crack closure occurs. The CROP model is verified with experimental data in part II of this paper.
1010‐cycle fatigue properties of 1800 MPa‐class JIS‐SUP7 spring steel
Authors: FURUYA Y. , ABE T. , MATSUOKA S.
Published: June 2003

1010‐cycle fatigue tests were conducted at 100 Hz for three years and at 20 kHz for one week on 1800 MPa‐class JIS‐SUP7 spring steel. Uniaxial tests up to 108 cycles were also conducted at 120 and 600 Hz. The 120 Hz tests had larger control volumes. The fatigue limit at 1010 cycles was lower than at 108 cycles, and any frequency effect was shown to be negligible. A size effect was found; the tests with larger control volumes showed results of lower fatigue strength.
The effect of T‐stress on plane strain dynamic crack growth in elastic–plastic materials
Authors: JAYADEVAN K. R. , NARASIMHAN R. , RAMAMURTHY T. S. , DATTAGURU B.
Published: June 2003

In this paper, the effects of T‐stress on steady, dynamic crack growth in an elastic–plastic material are examined using a modified boundary layer formulation. The analyses are carried out under mode I, plane strain conditions by employing a special finite element procedure based on moving crack tip coordinates. The material is assumed to obey the J2 flow theory of plasticity with isotropic power law hardening. The results show that the crack opening profile as well as the opening stress at a finite distance from the tip are strongly affected by the magnitude and sign of the T‐stress at any given crack speed. Further, it is found that the fracture toughness predicted by the analyses enhances significantly with negative T‐stress for both ductile and cleavage mode of crack growth.
Deficits in spatial learning and synaptic plasticity induced by the rapid and competitive broad‐spectrum cyclooxygenase inhibitor ibuprofen are reversed by increasing endogenous brain‐derived neurotrophic factor
Authors: Shaw Kendra N. , Commins Sean , O'Mara Shane M.
Published: June 2003

Cyclooxygenase (COX), which is present in two isoforms (COX1 and 2), synthesizes prostaglandins from arachidonic acid; it plays a crucial role in inflammation in both central and peripheral tissues. Here, we describe its role in synaptic plasticity and spatial learning in vivo via an effect on brain‐derived neurotrophic factor (BDNF) and prostaglandin E2 (PGE2; both measured by Elisa). We found that broad‐spectrum COX inhibition (BSCI) inhibits the induction of long‐term potentiation (LTP; the major contemporary model of synaptic plasticity), and causes substantial and sustained deficits in spatial learning in the watermaze. Increases in BDNF and PGE2 following spatial learning and LTP were also blocked. Importantly, 4 days of prior exercise in a running wheel increased endogenous BDNF levels sufficiently to reverse the BSCI of LTP and spatial learning, and restored a parallel increase in LTP and learning‐related BDNF and PGE2. In control experiments, we found that BSCI had no effect on baseline synaptic transmission or on the nonhippocampal visible‐platform task; there was no evidence of gastric ulceration from BSCI. COX2 is inhibited by glucorticoids; there was no difference in blood corticosterone levels as measured by radioimmunoassay in any condition. Thus, COX plays a previously undescribed, permissive role in synaptic plasticity and spatial learning via a BDNF‐associated mechanism.