bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of computer anxiety on price value trade‐off in the on‐line environment
Authors: Suri Rajneesh , Lee Julie Anne , Manchanda Rajesh V. , Monroe Kent B.
Published: May 2003

This research adds to the understanding of how consumers' comfort with computers influences their evaluation of prices for goods offered over the Internet. The effect of computer anxiety, under different motivational conditions, on the evaluation of price for a product in an on‐line environment was examined with the use of an experimental design. The results indicate that computer anxiety interacts with motivation to influence price perceptions, in a manner consistent with predictions derived from the process theories of attitude formation and change. Specifically, in the high‐motivation condition, subjects with a greater level of computer anxiety viewed high price as indicative of higher value than those with less computer anxiety (who evaluated the low price as better value). In the low‐motivation condition, both groups linked high price with higher perceived quality than the low price level. © 2003 Wiley Periodicals, Inc.
Determinants of internet auction success and closing price: An exploratory study
Authors: Gilkeson James H. , Reynolds Kristy
Published: May 2003

Although auctions have been examined extensively in economics, and to some degree in marketing, on‐line auctions are only beginning to receive research attention. Further, in both economics and marketing the research on auctions has relied primarily on rational, economic theories. This article investigates how particular on‐line auction features impact two important outcomes: auction success and final closing price. Traditional economic theories as well as theories from marketing and psychology are employed to provide a broader picture of on‐line auctions. Specifically, several key factors related to auction success and closing price for four types of sterling flatware in an on‐line auction site (eBay) are examined. The findings show that, across all four piece types, a reserve auction format, the relative opening price, and the number of bids unexplained by a low or high opening price are associated with both auction success and final closing price. © 2003 Wiley Periodicals, Inc.
Impact of poor microsurgical suture technique on tissue perfusion in a rat model
Authors: Krapohl Björn D. , Reichert Bert , Machens Hans‐Günther , Mailänder Peter
Published: May 2003

This study was designed to evaluate the effect of poor suture technique in microsurgical small‐vessel anastomosis on tissue microcirculation. Eighteen male Sprague‐Dawley rats were divided into three groups of six animals each: sham control group, regular suture group (control), and inverting suture group. In the regular suture group, a standard single‐stitch suture technique was used for microsurgical reanastomosis of the transected common iliac artery. In the inverting suture group, a suture technique was applied inverting the vessel wall, thus simulating poor suture technique. After 24 h, intravital microcirculatory measurements were obtained in the cremaster muscle flap. The inverting suture caused a significant drop in capillary perfusion from 6.40 (sham control) and 5.65 (regular suture) to 1.81 capillaries per visual field (P < 0.005). A poor microsurgical anastomosis may result in a significant reduction of peripheral tissue perfusion, although blood flow through the main feeding vessel is maintained. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:141–146 2003
Biodegradable, thermosensitive implant for approximating cylindrical structures: A preliminary study
Authors: Leung P.C. , Yew David , Wu Chi , Peng Shu‐Tu
Published: May 2003

A new invention, i.e., a biodegradable, thermosensitive hybrid gel composite in the form of a thin sheet, was used as an implant inside the rat and guinea pig to test its tissue reactions, degradation, and function as a bridging agent. Tissue tractions in subcutaneous tissue, in muscle, around a peripheral nerve, and around an artery were mild. Degradation made rapid progress, starting on the third day and completed in 2–3 weeks. The hybrid gel, when wrapped around the cut ends of a peripheral nerve or an artery, functioned well as a bridging tube. In the case of the cut nerve, regenerating fascicles crept through the tube which protected them from fibrosis. In the case of the cut artery, patency of flow was maintained, and arterial wall healing was complete in 2–3 weeks. The hybrid gel composite contracted at body temperature, thus holding well to body tissues. Its biodegradable and inert nature offers the potential for future use as a tissue wrap and bridging agent. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:123–129 2003
Synergistic effect of vincristine with tacrolimus or sirolimus in prevention of acute heart allograft rejection in the rat
Authors: Jiang Wenlei , Jiang Jingen , Xu Dasheng , Wang Xiang , Qi Shijie , Ouyang Jun , Ma Anlun , Vu Minh Diem , Bilolo Kupa K. , Chen Huifang
Published: May 2003

The application of multiple immunosuppressive therapy for organ transplantation could enhance therapeutic efficacy, while minimizing the toxicity of individual drugs used in the regimen. In this study, the effect of the combined therapy of vincristine (VCR) with tacrolimus (FK506) or sirolimus (rapamycin, RAPA) was tested in prevention of acute heart allograft rejection in the rat. A Brown Norway (BN, RT 1n) to Lewis (LEW, RT 11) rat combination was used in a heart allografting model. VCR was administered intraperitoneally once daily, while FK506 and RAPA were given by gavage once daily for 14 days after transplantation. There were dose‐related prolongations of mean survival time (MST) to monotherapy of VCR, FK506, or RAPA. The MST in combination therapy indicated that a synergistic interaction was produced when compared with the respective monotherapies: VCR 0.05 mg/kg/day + FK506 0.5 mg/kg/day (16.00 ± 1.79 days, P = 0.001; combination index (CI) = 0.557); VCR 0.05 mg/kg/day + FK506 1.0 mg/kg/day (29.00 ± 10.54 days, P = 0.001; CI = 0.598); VCR 0.05 mg/kg/day + RAPA 0.2 mg/kg/day (17.33 ± 1.97 days, P = 0.001; CI = 0.500); and VCR 0.05 mg/kg/day + RAPA 0.4 mg/kg/day (21.17 ± 3.19 days, P = 0.001; CI = 0.838). Combination therapy of VCR and FK506 or RAPA produced synergistic effects in prevention of acute heart allograft rejection in the rat. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:117–122 2003
Microsurgery simulators in virtual reality: Review
Authors: Erel Ertan , Aiyenibe Babatunde , Butler Peter E.M.
Published: May 2003

Surgical training is undergoing a rapid transformation, which has been influenced by advances in computer modeling. Increased pressure to reduce the use of animals in technical training has led to a new approach in teaching microsurgery. This new technology may prove to be a cost‐effective, portable, and nonhazardous way forward in microsurgical training. This paper reviews the current state of available technological models used in microsurgical training. In doing so, we review articles from the latest journals and authenticated Internet websites to compare and contrast these various methods. Finally, we look at the specific technique that has potential impact on the future modeling of microsurgical techniques. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:147–152 2003
Indications for vascularized free rectus abdominis musculocutaneous flap in oromandibular region in terms of efficiency of anterior rectus sheath
Authors: Yokoo Satoshi , Komori Takahide , Furudoi Syungo , Shibuya Yasuyuki , Umeda Masahiro , Ichinose Akihiro , Nomura Tadashi , Terashi Hiroto , Tahara Shinya , Nibu Ken‐Ichi
Published: May 2003

The anterior rectus sheath, efficacious in reconstructive surgery, is used in oromandibular reconstruction with the free rectus abdominis musculocutaneous flap. This study describes reconstruction with this sheath in 20 patients: to preserve only the swallowing function in 10 patients (formation of the bulge of the reconstructed oral floor and prevention of its sinking); to preserve both swallowing and articulation in 5 patients (formation of the bulge of the reconstructed tongue and prevention of its sinking, concurrent with a money‐pouch‐like reconstruction of the tongue, laryngeal suspension, and neuroanastomosis); and to prevent exposure of the reconstruction plate, replacing the resected mandibular continuity in 5 patients. The purpose of reconstruction was achieved in all patients. The vascularized free rectus abdominis musculocutaneous flap with a firm anterior rectus sheath may be the first choice for these types of reconstruction. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:96–102 2003
Development and validation of new model for microvascular transplantation of epiphyseal plate allografts with minimal adjoining epiphyseal and metaphyseal bone
Authors: Bray Peter W. , Neligan Peter C. , Bowen C. Vaughan A. , Danska Jayne S. , Boyer Martin I.
Published: May 2003

A model for the free allograft microvascular transplantation of rabbit proximal tibial epiphyseal plate allografts was developed, validated, and tested in an in vivo animal model. Transplants contained the minimum amount of adjacent epiphyseal and metaphyseal bone compatible with preservation of the epiphyseal‐plate vascular supply, as determined by corrosion casting. Perfusion to this graft was evaluated quantitatively using radioactive microspheres, and qualitatively using India‐ink injection. Female New Zealand White rabbits at 12 weeks of age were utilized. Vascularized transplantation of epiphyseal plate allografts was performed either into a defect of matched size in the iliac crest or into a soft‐tissue pocket without bone contact. Cyclosporine A immunosuppression (CSA) was administered daily for 6 weeks. Two control groups underwent identical surgical procedures, but had no postoperative immunosuppression. Epiphyseal plates both with and without bone contact, in rabbits immunosuppressed postoperatively with CSA, demonstrated longitudinal growth and preserved viability as determined by positive bromodeoxyuridine uptake. Control epiphyseal plates transferred without postoperative immunosuppression were uniformly nonviable. This new model has value as a basis for further studies into the clinical applicability of isolated epiphyseal‐plate transplants. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:153–163 2003
Rat model of laryngeal transplantation with normal circulation maintained by combination with the tongue
Authors: Nakai Kunihiro , Hosokawa Ko , Yano Kenji , Sakai Yasuo , Takagi Satoshi , Kubo Tateki , Kakibuchi Masao
Published: May 2003

Recent research on laryngeal transplantation used a rat model with physiologically abnormal circulation, because the common carotid artery was used for venous drainage. Since a model with normal circulation is better for accurate assessment, we developed a vascularized laryngeal graft, using the common carotid artery as the arterial supply and the external jugular vein as the venous drainage. The transplant included other tributaries from the tongue and the pharynx by combination with the tongue, because the tributaries from the larynx were very small. Ten transplants were performed. The transplanted organs were examined daily. Seven days after transplantation, the composite grafts were evaluated histologically. The mortality rate was 10%. All composite grafts were fully viable, and their structure was maintained in the remaining nine rats. Our model is appropriate for experiments on laryngeal transplantation. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:135–140 2003
Free osteocutaneous lateral arm flap: Anatomy and clinical applications
Authors: Haas Franz , Rappl Thomas , Koch Horst , Pittler Petra , Scharnagl Erwin
Published: May 2003

For many surgeons, the potential to reconstruct skin, fascia, tendon, or bone in a single‐stage procedure has made the lateral arm flap the technique of choice for reconstruction of complex defects. The aim of this study was to examine more closely how the humeral bone is supplied by the posterior collateral radial artery. To this end, we dissected 30 cadaver arms to determine the vascular relationship of the lateral arm flap to the humerus. The number of directly supplying vessels, and height to the lateral epicondyle of the humerus, were examined. The reconstructive potential of the osteocutaneous flap in different indications is analyzed in a series of five clinical cases. In all dissected extremities, we found one or two branches of the posterior collateral artery directly and constantly supplying the bone between 2–7 cm proximal to the lateral epicondyle. In five cases, combined defects, including bone, were successfully reconstructed with lateral arm flaps, including vascularized bone. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:87–95 2003
Clinical application of ipsilateral C7 nerve root transfer for treatment of C5 and C6 avulsion of brachial plexus
Authors: Gu Y.‐D. , Cai P.‐Q. , Xu F. , Peng F. , Chen L.
Published: May 2003

We applied a nerve transfer, using the ipsilateral C7 nerve root to treat the C5 and C6 root avulsion of the brachial plexus. Four patients with C5 and C6 preganglionic injury were operated on with this new technique from 1998–2000. Transfer of the spinal accessory nerve to the suprascapular nerve was simultaneously done in 2 these patients. After a follow‐up of 1–2.5 years, the muscle strength of elbow flexors recovered to M4 (Lovett) in all cases, shoulder abduction of >90° with external rotation of 30–40° was gained in two cases, and that of 15–45° with no external rotation in the other two cases. No remarkable impairment was found in all C7‐innervated muscles except for decrease of muscle power of 1 grade (Lovett) in the short run. This new technique shows promise as an efficacious and safe treatment for C5 and C6 root avulsion of the brachial plexus. However, it should be applied prudently when incomplete injuries of the lower trunk are involved. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:105–108 2003
Memories of the early years of insulin treatment in the UK
Authors: Gill G , Jones K , Smyth C , Bain S , Barnett A
Published: May 2003

The Diabetes UK Golden Year Study investigated a large cohort of Nabarro Medal winners (with type 1 diabetes of over 50 years duration) for genetic and clinical markers of long‐term survival. During over 400 interviews held, a wealth of stories were collected concerning experiences during the early years of insulin treatment in the UK. Some patients reported difficulties in finding physicians willing to treat them with insulin, and all had to adopt very strict and detailed diet regimens. Prolonged hospital admission at diagnosis was usual, and in those pre‐NHS days, considerable patient expense was common. One woman with type 1 diabetes reported pregnancies in the 1940s that resulted in six miscarriages, one stillbirth and three perinatal deaths. Most patients were surprisingly positive about their experiences, particularly those who came into contact with Dr Robin Lawrence of King's College Hospital. As one participant commented, he had learnt ‘self‐discipline, determination and will‐power’. Copyright © 2003 John Wiley & Sons, Ltd.
Implementing MICRO‐HOPE in primary care with extra nurse support
Authors: Farrell KA , Bowen C , Lovatt S
Published: May 2003

An audit of work to implement the MICRO‐HOPE study findings in a UK rural practice is presented. Seventy‐three out of an eligible group of 142 who fitted the HOPE trial criteria were not taking an ACE inhibitor. Of these, 60 were invited to a special clinic session with a visiting nurse to provide an opportunity to offer ACE inhibitor treatment and follow‐up. The average age of males (n=29) and females (n=31) was 70.7 (SD 9.9) and 70.1 (SD 8.9) respectively. The mean HbA1c of the invited group was 7.64% (CI 7.33–7.95%) and mean blood pressure was 138/75mmHg (CI 134–143/73–77mmHg).

Thirty‐five (58%) patients attended and 20 (33%) started taking ramipril as a result of the intervention. In the interim, three had been started on treatment by a hospital. At 12 weeks, 14 (23%) were still on treatment from the practice. Only two (10%) achieved the target dosage of 10mg ramipril daily. Six patients (30%) had side‐effects and stopped ramipril treatment. The total cost of the intervention was £3200.

The nurse‐led intervention increased the appropriate ACE inhibitor usage among people with type 2 diabetes from 49% to 59% over three months. The proportion of patients on either an ACE inhibitors or angiotensin II‐receptor antagonists rose from a baseline of 56% to 65% at six months.

For a brief intervention, this was a worthwhile effect. This audit shows that increasing ACE inhibitor use is resource intensive but its small scale may exaggerate the effect size. Clarity is needed around the issue of any ‘class effect’ for ACE inhibitors and how patients will cope with the increasing burden of medication. Copyright © 2003 John Wiley & Sons, Ltd.
Continuous quality control in diabetes care – implications
Authors: Baksi AK , Ball R , Bedford S , Hogan D , Thomas Z , Wilson P
Published: May 2003

A prospective evaluation of randomly selected consultations was conducted to assess the quality of diabetes care with regard to metabolic control, education of patients, and patient satisfaction. Patients completed an anonymous questionnaire. Health professionals completed a separate questionnaire to record data, and to indicate whether medication was changed and if any education was given.

All consultations were conducted by health professionals in secondary care, during six consecutive months. Patients responded to three statements, on a five‐point scale. The statements were: I feel better after this consultation; I was given enough time to discuss my problems; and I have learnt something new about diabetes at this consultation. Biomedical indicators were age, sex, type of therapy for diabetes, BMI, HbA1c, blood pressure and cholesterol.

Out of a total of 2213 consultations, 721 (32.6%) were audited; 89% of consultations were conducted by career grade clinicians. There was a high degree of patient satisfaction. The number of patients who had HbA1c of 7% or less was 38 (14%) in the insulin group, and 150 (33%) in the tablet group. Mean (SD) cholesterol was 5.25 (1.03) and 5.4 (1.03) in the insulin and tablet groups respectively. Blood pressure readings were lower in the insulin group.

In conclusion, the metabolic standards do not meet those currently recommended although there was a high degree of patient satisfaction. In order to be able to compare quality standards of this evaluation with those provided by other units, it is recommended that there is a national agreement on the cohort of patients in audit, the indicators to be used, and how each indicator is to be expressed. It is also necessary to establish a nationally agreed questionnaire, easy to administer in routine practice, to evaluate patient satisfaction and responses. Copyright © 2003 John Wiley & Sons, Ltd.
A survey of physicians' involvement in the management of diabetic foot ulcers in secondary health care
Authors: Jude EB , Oyibo SO , Millichip MM , Boulton AJM
Published: May 2003

A survey was conducted to investigate the management of diabetic foot ulcers by physicians in secondary health care. Questionnaires were sent to 160 consultant diabetologists in the UK. Questions covered a number of important issues regarding the management of diabetic foot ulcers.

A 50% response rate was recorded. Reportedly, 67.1% of respondents had a designated foot clinic. The majority (61.1%) of physicians used antibiotics for all clinically infected ulcers. Many (67.1%) used antibiotics until clinical signs of infection had resolved, 25.3% used antibiotics until the ulcer healed completely, while 7.6% used antibiotics for a fixed time period. Most (83.5%) physicians used a variety of techniques for off‐loading foot ulcers, and the majority (81.0%) reviewed patients fortnightly or more frequently. Some physicians (30–50%) admitted all patients with complicated foot ulcers: this number was less in centres that had a designated foot clinic (p=0.01). Two‐thirds of physicians used a combination of intravenous antibiotics for inpatients. The availability of vascular surgery, podiatry and orthotist services in each centre was reported by 91.1%, 92.4% and 77.2% of physicians respectively.

In conclusion, there is considerable variation and potential deficiencies in certain aspects of diabetic foot care in the UK. National consensus and guidelines are required to streamline the management of diabetic foot ulcers. Copyright © 2003 John Wiley & Sons, Ltd.
Expert opinion statement on the use of insulin therapy in patients with type 2 diabetes in primary care
Authors: Barnett AH , Capaldi B , Davies‐Lyons M , Farooqi A , Gadsby R , Gilroy J , Hill J , Hughes EJ , Kirby M , Owens D , Tasker PR W , Vora J
Published: May 2003

Although the United Kingdom Prospective Diabetes Study (UKPDS) demonstrated the undoubted benefits of tight glycaemic control, over time most patients required oral combination therapy or insulin even to get close to glycaemic targets. Despite this, much confusion remains regarding the place of insulin therapy in management of type 2 diabetes.

In this article we provide a series of questions and answers relating to the use of insulin therapy in primary care based on the clinical experience of a multidisciplinary group of health professionals working in this area. We overview the undoubted advantage (and pitfalls) of intensive glycaemic control in preventing/delaying vascular complications and provide recommendations on indications for insulin initiation. We go on to discuss the question of who should prescribe insulin and in what clinical setting. Ideally, initiation should be in a clinical setting where the competence and skills exist in a convenient location for the patient. We then consider which insulin regimens should be used in type 2 diabetes with discussion of insulin in combination with oral agents, further intensified insulin treatment (basal bolus regimens) and twice daily premixed insulins. Insulin start doses are also discussed as well as titration regimens. We also consider the role of the rapid‐acting and long‐acting analogues in insulin therapy for type 2 diabetes.

We conclude that insulin prescribing in primary care is becoming a reality and probably a necessity in view of the increasing number of patients with type 2 diabetes. This will require appropriate training, funding and support at all levels (particularly from secondary care) if this is to be successful. We hope that this article will help to simplify and demystify insulin prescribing in primary care and allow more patients to be appropriately and optimally treated. Copyright © 2003 John Wiley & Sons, Ltd.
Genetic testing in maturity onset diabetes of the young (MODY) – practical guidelines for professionals
Authors: Shepherd M
Published: May 2003

Diagnostic and predictive genetic testing is possible in up to 80% of maturity onset diabetes of the young (MODY) families. Diagnostic genetic testing allows confirmation of MODY and defines the subtype. This allows appropriate advice regarding treatment and likely clinical course to be given. Those undergoing genetic testing should have the opportunity to discuss the implications of the tests and their possible reactions. If HNF‐1α is identified, patients on insulin from diagnosis may benefit from a trial of sulphonylureas. This article provides the first specific guidelines relating to the provision of genetic testing in MODY. Copyright © 2003 John Wiley & Sons, Ltd.
Fragmentation of dihydroxyacetone kinase 1 from Saccharomyces cerevisiae indicates a two‐domain structure
Authors: Molin Mikael , Larsson Thomas , Karlsson Karl‐Anders , Blomberg Anders
Published: May 2003

Global protein expression in Saccharomyces cerevisiae strains either deleted for both yeast dihydroxyacetone kinases (DAK1 and DAK2) or overexpressing DAK1, was characterized by two‐dimensional polyacrylamide gel electrophoresis (2‐D PAGE). We found protein expression in the double deletion strain to be highly similar to wild‐type. In the strain overexpressing Dak1p, nine spots representing fragments of the Dak1p protein in the size range 40–20 kDa and amounting to approximately 30% of total Dak1p, were discovered (native size Dak1p migrates at roughly 60 kDa). Fragments were characterized by matrix‐assisted laser desorption/ionization mass spectrometry and electrospray mass spectrometry analyses to represent either the N‐ or the C‐terminal part of the DAK1 protein. Cleavage points, predicted from mass spectrometry and 2‐D PAGE data, mapped almost exclusively in the middle region showing low sequence conservation between Dak1p and its closest homologues. We hypothesize that observed Dak1p fragments represent stable structural domains shielded from access by native endoproteases. Furthermore, overexpressing Dak1p with the non‐native N‐terminus (M)A‐, resulted in native size Dak1p and N‐terminal Dak1p fragments appearing in two major 2‐D PAGE forms of approximately equal size and abundance, but with slightly different isoelectric points. However, when overexpressing Dak1p with the native N‐terminus (M)S‐, only the more acidic 2‐D PAGE form appeared. In the N‐terminal acetyltransferase mutant nat1Δ, (M)A‐Dak1p species were converted into the basic form, arguing twin spots to represent forms with acetylated and deacetylated N‐termini. Data thus indicated that (M)A‐N‐termini, in the Dak1p context, were NatA substrates recognized with 50% lower efficiency than (M)S‐N‐termini.
Modulation of gene expression by extracellular pH variations in human fibroblasts: A transcriptomic and proteomic study
Authors: Bumke Maja A. , Neri Dario , Elia Giuliano
Published: May 2003

Homeostasis of the intracellular ionic concentration, in particular that of hydrogen ions, is pivotal to the maintenance of cell function and viability. Nonetheless, pH fluctuations in both the intracellular and the extracellular compartments can occurr during development, in physiological processes and in disease. The influence of pH variations on gene expression has been studied in different model systems, but only for a limited number of genes. We have performed a broad range analysis of the patterns of gene expression in normal human dermal fibroblasts at two different pH values (in the presence and in the absence of serum), with the aim of getting a deeper insight into the regulation of the transcriptional program as a response to a pH change. Using the Affymetrix gene chip system, we found that the expression of 2068 genes (out of 12 565) was modulated by more than two‐fold at 24, 48 or 72 h after the shift of the culture medium pH to a more acidic value, stanniocalcin 1 being a remarkable example of a strongly up‐regulated gene. Genes displaying a modulated pattern of expression included, among others, cell cycle regulators (consistent with the observation that acidic pH abolishes the growth of fibroblasts in culture) and relevant extracellular matrix (ECM) components. Extracellular matrix protein 2, a protein with a restricted pattern of expression in adult human tissues, was found to be remarkably overexpressed as a consequence of serum starvation. Since ECM components, whose expression is controlled by pH, have been used as targets for biomolecular intervention, we have complemented the Affymetrix analysis with a two‐dimensional polyacrylamide gel electrophoresis analysis of proteins which are differentially secreted by fibroblasts at acidic or basic pH. Mass spectrometric analysis of more than 650 protein spots allowed the identification of 170 protein isoforms or fragments, belonging to 40 different proteins. Some proteins were only expressed at basic pH (including, for instance, tetranectin), while others (e.g., agrin) were only detectable at acidic pH. Some of the identified proteins may represent promising candidate targets for biomedical applications, e.g., for antibody‐mediated vascular targeting strategies.
Proteomic analysis of the reactive phenotype of astrocytes following endothelin‐1 exposure
Authors: Egnaczyk Gregory F. , Pomonis James D. , Schmidt Julie A. , Rogers Scott D. , Peters Christopher , Ghilardi Joseph R. , Mantyh Patrick W. , Maggio John E.
Published: May 2003

Reactive gliosis is an invariant feature of the pathology of central nervous system (CNS) injury and a major determinant of neuronal survival and regeneration. To begin to understand the alterations in astrocyte protein expression that drive glial changes that occur following injury, we used an established model system (endothelin‐1 stimulation of hypertrophy) and proteomic analysis to define a discrete set of differentially expressed proteins and post‐translational modifications that occur as the astrocytes change from a quiescent to a reactive state. This orchestrated set of changes included proteins involved in cytoskeletal reorganization (caldesmon, calponin, alpha B‐crystallin, stathmin, collapsing response mediator protein‐2), cell adhesion (vinculin, galectin‐1), signal transduction (RACK‐1) and astrocyte differentiation (glutamine synthetase). Using proteomic analysis to understand what drives astrocyte expression of these functionally divergent molecules may offer insight into the mechanisms by which astrocytes can exhibit both pro‐regenerative and anti‐regenerative activities following CNS injury.
Proteome analysis of the purine stimulon from Lactococcus lactis
Authors: Beyer Natascha H. , Roepstorff Peter , Hammer Karin , Kilstrup Mogens
Published: May 2003

A comparative expression proteome analysis was carried out by analyzing differential expression patterns of pulse‐labelled proteins on two‐dimensional gels under standard conditions and during purine nucleotide starvation, followed by mass spectrometric identification of regulated proteins. Based upon the expression patterns, three stimulons could be identified in Lactococcus lactis subsp. cremoris. The Psu proteins (purine starvation up‐regulated) had increased synthesis during purine depletion in a purine auxotroph. Among these proteins were enzymes of the purine biosynthesis pathways (PurE, PurS, PurM, PurL), and enzymes involved in the generation of C1 units (GlyA, Fhs). C1 units are primarily required for purine biosynthesis. Upon analysis of the nucleotide sequence preceding the structural genes for these proteins in the L. lactis IL1403 genome sequence showed that all contained PurBox‐Pribnov box structures resembling the PurR activated promoters for the purDEK and purCSQLF operons. Most, and possibly all members of the Psu stimulon are thus members of the PurR regulon. Five Psu proteins could not be identified. The second stimulon, the Psd stimulon (purine starvation decreased), whose members are down‐regulated during purine depletion, contained proteins related to protein synthesis (PpsB, EF‐TS, trigger factor), or to GTPases (FtsZ, EF‐TS); or are involved in energy metabolism (GapB, CcpA). No common regulatory elements could be found for members of this stimulon. Two Psd proteins escaped identification. The last, Dcu (decoynine up‐regulated), stimulon contained proteins whose synthesis escaped the severe general depression during inhibition of the GMP synthetase by decoynine. This regulon was comprised of mostly glycolytic enzymes (fructose bisphosphate aldolase, enolase, pyruvate kinase) and translation elongation factors (GTPases: EF‐TU, EF‐G). Two Dcu proteins could not be identified. Out of 28 proteins subjected to mass spectrometry, 19 could be readily identified despite the fact that only the genome sequence of a strain of L. lactis subsp. lactis was available. The two subspecies share about 85% sequence identity, comparable to the genetic distance between Escherichia coli and Salmonella typhimurium. A success rate of 68% indicates that it may be feasible to perform proteomics based upon genomic sequences of relatives outside the genus.
Adsorption of bovine serum albumin onto poly(methyl methacrylate) stereocomplex films with a molecularly regulated nanostructure
Authors: Hamada Ken‐Ichi , Yamashita Keiko , Serizawa Takeshi , Kitayama Tatsuki , Akashi Mitsuru
Published: May 2003

Stereoregular poly(methyl methacrylate)s (PMMAs) were stepwise assembled on a quartz crystal microbalance (QCM) substrate after the immersion of the QCM into alternating acetonitrile solutions at ambient temperature. A quantitative QCM analysis at each step showed stereocomplex formation on the substrate surface. The adsorption of bovine serum albumin (BSA) onto stereocomplex films with a molecularly regulated nanostructure was analyzed quantitatively. The adsorption constant and the maximum adsorption amount, calculated by the assumption of Langmuir‐type adsorption, showed that BSA adsorbed with a relatively weak interaction onto the stereocomplex films. The BSA adsorption onto the stereocomplex films occurred in an end‐on manner, with a smaller adsorption constant than for that onto individual spin‐coated films. The amount of BSA adsorbed was significantly affected by the molecular weight of syndiotactic PMMA. Attenuated total reflection spectra indicated that BSA adsorbed onto the films with or without denaturing. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1807–1812, 2003
Synthesis of a novel hybrid liquid‐crystalline rod–coil diblock copolymer
Authors: Yi Yi , Wan Xinhua , Fan Xinghe , Dong Rong , Zhou Qifeng
Published: May 2003

A series of novel rod–coil diblock copolymers on the basis of mesogen‐jacketed liquid‐crystalline polymer were successfully prepared by atom transfer radical polymerization from the flexible polydimethylsiloxane (PDMS) macroinitiator. The hybrid diblock copolymers, poly{2,5‐bis[(4‐methoxyphenyl)oxycarbonyl]styrene}‐block‐polydimethylsiloxane, had number‐average molecular weights (Mn's) ranging from 9500 to 30,900 and relatively narrow polydispersities (≤1.34). The polymerization proceeded with first‐order kinetics. Data from differential scanning calorimetry validated the microphase separation of the diblock copolymers. All block copolymers exhibited thermotropic liquid‐crystalline behavior except for the one withMnbeing 9500. Four liquid‐crystalline diblock copolymers with PDMS weight fractions of more than 18% had two distinctive glass‐transition temperatures. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1799–1806, 2003
Further evidence for the inseparability of the theoretical enthalpic terminal and penultimate unit effects in the radical copolymerization of styrene with acrylonitrile
Authors: Kaim Andrzej , Cieplak Piotr
Published: May 2003

The theoretical enthalpies of propagation reactions at 0 K without zero‐point vibrational energy corrections according to terminal and penultimate models of the radical copolymerization of styrene with acrylonitrile are reported from molecular orbital calculations at the following levels of theory and basis sets: HF/6‐31G(d); B3‐LYP/6‐31G(d); B3‐LYP/6‐311G(d,p) and B3‐LYP/6‐311+G(3df)//6‐311G(d,p). Both the enthalpic terminal and penultimate unit effects, determined according to the theoretical thermochemistry, depend on the level of theory and basis set used for the molecular orbital calculations. The best performing B3LYP/6‐311+G(3df)//B3LYP/6‐311G(d,p) procedure gives theoretical enthalpies for the addition of styrene and acrylonitrile to CH that differ from experimental values by 0.6 and 1.6 kcal mol−1, respectively. An analysis of the results obtained here leads to the conclusion that at least for the styrene–acrylonitrile monomer system, that is, a monomer system known as one of the few systems that do not conform to terminal model composition and microstructure equations, the enthalpic terminal unit effects seem to depend on the penultimate units of the growing radical. This finding, together with the outcome from our previous work on the dependence of the penultimate effects on the terminal units in a growing macroradical, indicates the inseparability of the enthalpic terminal (implicit) and explicit penultimate unit effects on the radical copolymerization. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1778–1787, 2003
Preparation of a graded‐index polymeric preform by swollen bulk polymerization
Authors: Zhen Zhen , Li Xiao‐Dong , Wang Xin‐Qiu , Huang Yong , Liu Xin‐Hou
Published: May 2003

A swollen bulk polymerization approach for the preparation of a preform for manufacturing graded‐index plastic optical fibers was examined. The preform prepared by the proposed approach was transparent and bubble‐free and had a parabolic profile of the refractive index, with the highest refractive index at the center of the rod. The influences of the polymerization temperature and the type of dopant on the properties of the prepared preform were discussed. A higher temperature resulted in a steeper parabolic profile of the refractive index for the formed preform, and a lower temperature resulted in a higher refractive index near the core‐cladding region of the preform. The refractive‐index profiles of the preform were affected by the addition of the different types of dopants used. The concentration distribution of the dopant in the preform correlated to the refractive‐index distribution. In a comparison of bromobenzene (BB) and 1,2,4‐trichlorobenzene (TB) as dopants, it was observed that BB distributions along the profile were more uniform than TB distributions, and a dopant with a larger molecular volume was more concentrated in the core center. It was concluded that the refractive‐index distribution of the graded‐index preform could be controlled by the both temperature and the addition of different types of dopants during the swollen bulk polymerization process. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1813–1818, 2003
Elementary reaction analysis of the radical polymerization of α‐ethyl β‐N‐(α′‐methylbenzyl)itaconamates carrying (RS)‐ and (S)‐α‐methylbenzylaminocarbonyl groups
Authors: Sato Tsuneyuki , Hashimoto Masahiko , Seno Makiko , Hirano Tomohiro
Published: May 2003

The polymerizations of α‐ethyl β‐N‐(α′‐methylbenzyl)itaconamates carrying (RS)‐ and (S)‐α‐methylbenzylaminocarbonyl groups (RS‐EMBI and S‐EMBI) with dimethyl 2,2′‐azobisisobutyrate (MAIB) were studied in methanol (MeOH) and in benzene kinetically and with electron spin resonance (ESR) spectroscopy. The initial polymerization rate (Rp) at 60 °C was given by Rp = k[MAIB]0.58 ± 0.05[RS‐EMBI]2.4 ± 0.l and Rp = k[MAIB]0.61 ± 0.05[S‐EMBI]2.3 ± 0.l in MeOH and Rp = k[MAIB]0.54 ± 0.05[RS‐EMBI]1.7 ± 0.l in benzene. The rate constants of initiation (kdf), propagation (kp), and termination (kt) as elementary reactions were estimated by ESR, where kd is the rate constant of MAIB decomposition and f is the initiator efficiency. The kp values of RS‐EMBI (0.50–1.27 L/mol s) and S‐EMBI (0.42–1.32 L/mol s) in MeOH increased with increasing monomer concentrations, whereas the kt values (0.20−7.78 × 105 L/mol s for RS‐EMBI and 0.18−6.27 × 105 L/mol s for S‐EMBI) decreased with increasing monomer concentrations. Such relations of Rp with kp and kt were responsible for the unusually high dependence of Rp on the monomer concentration. The activation energies of the elementary reactions were also determined from the values of kdf, kp, and kt at different temperatures. Rp and kp of RS‐EMBI and S‐EMBI in benzene were considerably higher than those in MeOH. Rp of RS‐EMBI was somewhat higher than that of S‐EMBI in both MeOH and benzene. Such effects of the kinds of solvents and monomers on Rp were explicable in terms of the different monomer associations, as analyzed by 1H NMR. The copolymerization of RS‐EMBI with styrene was examined at 60 °C in benzene. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1819–1830, 2003
Synthesis and characterization of fluorinated poly(amide imide)s derived from 1,4‐bis(2′‐trifluoromethyl‐4′‐trimellitimidophenoxy)benzene and aromatic diamines
Authors: Li Z. X. , Fan L. , Ge Z. Y. , Wu J. T. , Yang S. Y.
Published: May 2003

A series of fluorinated poly(amide imide)s were prepared from 1,4‐bis(2′‐trifluoromethyl‐4′‐trimellitimidophenoxy)benzene and various aromatic diamines [3,3′,5,5′‐tetramethyl‐4,4′‐diaminediphenylmethane, α,α‐bis(4‐amino‐3,5‐dimethyl phenyl)‐3′‐trifluoromethylphenylmethane, 1,4‐bis(4′‐amino‐2′‐trifluoromethylphenoxy)benzene, 4‐(3′‐trifluoromethylphenyl)‐2,6‐bis(3′‐aminophenyl)pyridine, and 1,1‐bis(4′‐aminophenyl)‐1‐(3′‐trifluoromethylphenyl)‐2,2,2‐trifluoroethane]. The fluorinated poly(amide imide)s, prepared by a one‐step polycondensation procedure, had good solubility both in strong aprotic solvents, such as N‐methyl‐2‐pyrrolidinone, dimethylacetamide, dimethylformamide, dimethyl sulfoxide, and cyclopentanone, and in common organic solvents, such as tetrahydrofuran and m‐cresol. Strong and flexible polymer films with tensile strengths of 84–99 MPa and ultimate elongation values of 6–9% were prepared by the casting of polymer solutions onto glass substrates, followed by thermal baking. The poly(amide imide) films exhibited high thermal stability, with glass‐transition temperatures of 257–266 °C and initial thermal decomposition temperatures of greater than 540 °C. The polymer films also had good dielectric properties, with dielectric constants of 3.26–3.52 and dissipation factors of 3.0–7.7 × 10−3, and acceptable electrical insulating properties. The balance of excellent solubility and thermal stability associated with good mechanical and electrical properties made the poly(amide imide)s potential candidates for practical applications in the microelectronics industry and other related fields. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1831–1840, 2003
Clinical application of direct sputum sensitivity testing in a severe infective exacerbation of cystic fibrosis
Authors: Serisier David J. , Jones Graeme , Tuck Andrew , Connett Gary , Carroll Mary P.
Published: May 2003

A 16‐year‐old male with cystic fibrosis (CF) was admitted to hospital with a severe infective exacerbation. Despite standard management, including conventionally selected intravenous antibiotics for Pseudomonas aeruginosa, chest physiotherapy, and institution of noninvasive ventilation (NIV) for progressive hypercapneic respiratory failure, he continued to deteriorate. Direct sputum sensitivity testing (DSST) revealed a novel combination of antibiotics that resulted in a rapid and remarkable clinical improvement. DSST is a form of “whole” sputum sensitivity testing that provides information on antibiotic synergy, and may more accurately reflect in vivo antibiotic sensitivity patterns in cystic fibrosis. Pediatr Pulmonol. 2003; 35:463–466. © 2003 Wiley‐Liss, Inc.
Expression study of three secretory proteins (prostatic secretory protein of 94 amino acids, probasin, and seminal vesicle secretion II) in dysplastic and neoplastic rat prostates
Authors: Kwong Joseph , Lui K. , Chan Peter S.F. , Ho Shuk‐Mei , Wong Y.C. , Xuan J.W. , Chan Franky L.
Published: May 2003

Background

Prostatic secretory protein of 94 amino acids (PSP94), probasin, and seminal vesicle secretion II (SVSII) are the three major proteins secreted by the lateral lobe of the rat prostate gland. Among these proteins, rodent PSP94 but not probasin and SVSII has a human homologue and it is also a major secretory protein of the human prostate, in addition to prostatic acid phosphatase and prostate‐specific antigen.

Methods

In this study, we examined and compared the mRNA expression of these three secretory markers in three rat models of prostate cancer including the sex steroid‐induced dysplasia (prostatic intraepithelial neoplasia or PIN) in Noble (Nb) rat model, an androgen‐independent Nb rat prostatic tumor (AIT) and Dunning rat prostatic adenocarcinomas (both androgen‐dependent and ‐independent) by in situ hybridization (ISH), reverse transcriptase‐polymerase chain reaction (RT‐PCR), and immunohistochemistry.

Results

The transcripts for the three markers were highly expressed in the secretory epithelium of normal lateral prostate (LP). Their hybridization signals became reduced in the epithelial cells in the low‐grade PINs and significantly weakened or lost in the high‐grade PINs induced in the LP. Interestingly, we observed that some dysplastic cells located at the basal compartment of the PIN lesions, and nests of outpouching epithelial cells in the vicinity of PINs, expressed positive hybridization signals of three markers. In the adenocarcinoma, signals of probasin but not PSP94 and SVSII were detected. No hybridization signals were detected in both Dunning and AIT tumors. By RT‐PCR, transcripts for these proteins were still detected but significantly reduced in the Dunning tumors, whereas in the AIT tumor, only SVSII transcripts were detected. Immunohistochemistry of PSP94 also showed a reduced staining in the PIN lesions, but no immunoreactivity was seen in the rat prostatic tumors.

Conclusions

The mRNA expression of the three prostatic secretory markers were decreased in the hormone‐induced PINs and in two rat prostatic tumors, indicating that the androgen‐regulated secretory differentiation was impaired during the development of the premalignant lesion and further reduced in advanced tumors. The abnormal expression pattern of these secretory markers and androgen receptor (AR) in the basal compartment of the PIN lesions suggests that there is a population of cell types with secretory phenotype appearing in the basal cell layer during the early malignant transformation of the prostatic epithelium. Prostate 56: 81–97, 2003. © 2003 Wiley‐Liss, Inc.
Prostate cancer expression of runt‐domain transcription factor Runx2, a key regulator of osteoblast differentiation and function
Authors: Brubaker Kristen D. , Vessella Robert L. , Brown Lisha G. , Corey Eva
Published: May 2003

BACKGROUND

Prostate cancer (CaP) bone metastases express numerous proteins associated with bone cells. Specific transcription factors, including Runx2, regulate the expression of many bone‐related factors in osteoblasts. Expression of these transcription factors in CaP may be linked to the ability of CaP bone metastases to influence bone remodeling.

METHODS

CaP tissues and cell lines were analyzed for expression of Runx2 mRNA by RT‐PCR and in situ hybridization, and protein by immunohistochemistry, Western blotting, and electrophoretic mobility shift assays (EMSA).

RESULTS

Runx2 mRNA and protein were detected in CaP tissues and cell lines. A specific Runx2: OSE2 complex could be formed with PC‐3 nuclear extracts.

CONCLUSIONS

Expression of Runx2 in CaP may be the molecular switch that is associated with expression of various bone‐specific factors in CaP. In turn, expression of these factors can influence bone remodeling and possibly play a role in the growth and survival of CaP in bone. Prostate 56: 13–22, 2003. © 2003 Wiley‐Liss, Inc.
Agonist–PPARγ interactions: Molecular modeling study with docking approach
Authors: Xu Xiao Ying , Cheng Feng , Shen Jian Hua , Luo Xiao Min , Chen Li Li , Yue Li Duo , Du Yi , Ye Fei , Jiang Shan Hao , Zhu Da Yuan , Jiang Hua Liang , Chen Kai Xian
Published: May 2003

Docking simulation of 18 agonists with the ligand binding pocket (LBP) of PPARγ has been performed. The binding conformations and binding affinities of these agonists were obtained by use of the flexible docking protocol FlexX. Test compound calculations indicated that FlexX can reproduce the binding conformation of the crystal structure (root mean square deviation = 1.43 Å); moreover, the predicted binding affinities correlate well with the activities of these agonists. The interaction model and pharmacophore of PPARγ agonists were derived and the difference in biologic activities of these agonists can be well explained. The PPARγ agonists must have both polar head and the hydrophobic tail, which form hydrogen bonds and hydrophobic contacts with hydrophilic and hydrophobic regions of the LBP of PPARγ, respectively. In addition, a suitable linker is also necessary. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem 93: 405–410, 2003