bluuebunny/crossref_metadata_2025 huggingface dataset:
Microvascular free tissue transfer in elderly patients: The Toronto experience
Authors: Beausang Eamon S. , Ang Erik E. , Lipa Joan E. , Irish Jonathan C. , Brown Dale H. , Gullane Patrick J. , Neligan Peter C.
Published: June 2003

Background.

Microvascular free tissue transfer has become an accepted and versatile method of reconstruction in the head and neck region, offering a one‐stage procedure and thus reducing the number and length of hospital stays. Many of the patients requiring head and neck free flaps are elderly, with concomitant medical problems, including respiratory and cardiovascular compromise, and are therefore potentially at higher risk of adverse outcomes. In addition, they frequently have a history of heavy alcohol and cigarette consumption, which can compound the risks.

Methods.

We analyzed a series of 288 intraoral free flap reconstructions and arbitrarily divided them into four groups depending on age: <50, 51–60, 61–70, >70. These reconstructions were all performed for malignant lesions. Preoperative medical problems, including ischemic heart disease, hypertension, chronic obstructive pulmonary disease, peripheral vascular disease, and diabetes, were assessed and compared among the different age groups.

Conclusions.

Our results suggest that free flap surgery is a safe technique in elderly patients with comparable surgical complications to a younger patient population. As a result of concomitant medical problems, however, postoperative medical complications are more frequent in the older age groups, with a resultant increase in length of hospital stay. © 2003 Wiley Periodicals, Inc. Head Neck 25: 549–553, 2003
Biodegradable polymer–mediated intratumoral delivery of cisplatin for treatment of human head and neck squamous cell carcinoma in a chimeric mouse model
Authors: Chen Fang‐An , Kuriakose M. Abraham , Zhou Ming‐Xing , DeLacure Mark D. , Dunn Richard L.
Published: June 2003

Background.

The effectiveness of chemotherapeutic agents is proportional to the dose of the agents at their targets; however, the dose is limited by systemic toxicity. Attempts have been made to improve therapeutic effectiveness by increasing maximum tolerated dose (MTD) of chemotherapeutic agents using various local and regional drug delivery systems. Herein we report the use of an injectable biodegradable polymer to deliver cisplatin for intratumoral treatment of human head and neck squamous cell carcinoma (HNSCC) in a chimeric mouse model. The objectives of this research project were (1) to determine the release kinetics of cisplatin from the polymer delivery system, (2) to identify the MTD of polymer‐delivered cisplatin, and (3) to evaluate its therapeutic efficacy.

Methods.

To determine the in vivo release kinetics, cisplatin‐loaded polymer was injected subcutaneously into rats. Implants were removed and analyzed for remaining cisplatin by a high‐performance liquid chromatography technique. Sera from these rats were assayed for platinum by atomic absorption spectrophotometry. For MTD determination, SCID mice were engrafted subcutaneously with fresh biopsy specimens of HNSCC. Various doses of free or polymer‐loaded cisplatin were injected intratumorally. MTD was estimated based on the threshold at which all mice survived. The antitumor efficacy of free and polymer‐loaded cisplatin at their respective MTD was assayed on the same chimeric mouse model.

Results.

The polymer delivery system released 80% of the loaded cisplatin in vivo over a 7‐day period. The polymer‐delivered cisplatin exhibited higher MTD (36 mg/kg) than free cisplatin (18 mg/kg) and had a statistically significant tumor suppression effect compared with free cisplatin when used at their respective MTD.

Conclusions.

The polymer delivery system can sustain cisplatin release for a period of 7 days. It can increase MTD and potentially enhance the antitumor efficacy of cisplatin against human head and neck cancers. © 2003 Wiley Periodicals, Inc. Head Neck 25: 554–560, 2003
Anterior skull base surgery for malignant tumors: A multivariate analysis of 27 years of experience
Authors: Bentz Brandon G. , Bilsky Mark H. , Shah Jatin P. , Kraus Dennis
Published: June 2003

Introduction.

Few studies have examined prognostic factors that have an impact on outcomes in anterior skull base surgery by multivariate analysis.

Methods.

We retrospectively examined our institution's skull base experience from 1973–2000.

Results.

During this time, 166 patients underwent an anterior skull base resection for malignancy (median age, 53 years; range, 6–92 years). The 5‐year relapse‐free and disease‐specific survival was 41% and 57% (median follow‐up, 53 months). Multivariate analysis found that dural invasion, primary histologic diagnosis, and margin status had a significant impact on relapse‐free and disease‐specific survival.

Conclusions.

These data indicate that patients with anterior skull base malignancies are treated successfully with skull base surgery. Patients demonstrating adverse prognostic variables such as dural invasion, adverse histologic findings, and/or positive margins should be considered for the addition of adjuvant therapy or innovative therapies as they become available in the future. © 2003 Wiley Periodicals, Inc. Head Neck 25: 515–520, 2003
The value of frozen section in intraoperative surgical management of thyroid follicular carcinoma
Authors: Došen Danijel , Turić Marko , Šmalcelj Josip , Janušić Renato , Pastorčić Grgić Marija , Šeparović Viktor
Published: June 2003

Background.

Preoperative and intraoperative diagnosis of follicular carcinoma (FC), resulting in one‐stage surgical treatment of follicular thyroid tumors, is an important issue in thyroid surgery.

Methods.

In the 10‐year period there were 4158 operations performed on thyroid gland. There were 1559 patients with follicular tumors, 70 (4.4%) of them having FC. We analyzed the groups of patients with FC determined on frozen section (FS) and permanent section (PS) according to duration of clinical symptoms, ultrasound (US) examination, tumor size, patient gender and age, intensity of invasion, localization, and multiple or solitary occurrence of tumor.

Results.

FC was diagnosed in 39 (55.7%) patients on frozen section (FS). Among the encapsulated (minimal invasion) carcinomas, the FS was accurate in 19 of 33 (57.6%) FC and in 5 of 15 (27.8%) Hürthle cell carcinomas (HCC); among extensively invasive carcinoma in 11 of 14 (78.6%) FC and in 4 of 5 (80.0%) HCC. FC was significantly more common in men (p < .001) and in the right lobe (p < .05). We did not find statistically significant differences concerning duration of symptoms, US examination, tumor size, patient age, and multiple or solitary occurrence of the tumor between the patients with FC diagnosed on FS and the patients with FC diagnosed on PS.

Conclusions.

The intraoperative diagnosis of FC is difficult. Although the percentage of false‐negative results was relatively high (44.3%), there were no false‐positive results. This means that the second operation was avoided in 55.7% of the patients, and no unnecessary thyroidectomies were performed. FS biopsy is an important method in surgery of follicular tumors. Improved technical support and the ability to analyze a greater number of slides will increase the accuracy of the method. © 2003 Wiley Periodicals, Inc. Head Neck 25: 521–528, 2003
Total upper lip reconstruction with a free temporal scalp flap: Long‐term follow‐up
Authors: Chang Kao‐Ping , Lai Chung‐Sheng , Tsai Chih‐Cheng , Lin Tsai‐Ming , Lin Sin‐Daw
Published: June 2003

Background.

In men, reconstruction of large full‐thickness defects of the upper lip requires both an inner layer to replace the mucosal lining and an outer hair‐bearing layer.

Methods.

When locating the superficial temporal vessels, the design of the temporal flap is marked following the hairline needed. After meticulously dissecting the flap, it is inset and microanastomosed with the facial blood vessels. The internal mucosal layer of the flap is grafted on. During the follow‐up period, the sensory recovery and motor functions are examined and recorded.

Results.

The postoperative courses were uneventful, and patients were satisfied with the results. One patient has a long follow‐up period of 18 years.

Conclusions.

The free temporal scalp hair‐bearing flap offers a reasonable alternative to conventional techniques in the reconstruction of large defects of the male upper lip or even a total upper lip. It is a single‐staged, relatively simple method of providing hair‐bearing skin to the upper lip. © 2003 Wiley Periodicals, Inc. Head Neck 25: 602–605, 2003
Parameters that predict local control after definitive radiotherapy for squamous cell carcinoma of the head and neck
Authors: Mendenhall William M. , Morris Christopher G. , Amdur Robert J. , Hinerman Russell W. , Mancuso Anthony A.
Published: June 2003

Purpose.

To analyze parameters that may influence the likelihood of local control after definitive radiotherapy for head and neck cancer.

Methods.

Between April 1980 and January 2000, 404 patients were treated with definitive RT alone (358 patients) or combined with adjuvant chemotherapy (46 patients) at our institution and were followed up for 0.25 to 20.25 years (median, 3.5 years.) All living patients were followed up for at least 2 years. All patients had the primary tumor volume calculated on pretreatment CT. End points were local control after RT and local control after RT without a severe late complication. Parameters evaluated in multivariate analyses of these end points included primary site, T stage, primary tumor volume, N stage, histologic differentiation, fractionation schedule, adjuvant chemotherapy, and gender.

Results.

The rates of local control and local control without a severe late complication after RT were significantly influenced by primary tumor volume for patients with cancer of the supraglottic larynx and true vocal cord. In contrast, the rates of local control and local control without severe complications for patients with tumors of the oropharynx and hypopharynx were less influenced by tumor volume. Multivariate analysis of the overall population revealed that the only parameter that was significantly related to the probability of local control after RT was T stage. Multivariate analyses stratified by primary site revealed that tumor volume significantly influenced local control for patients with cancers of the supraglottis (p= .0220) and glottis (p= .0042) but not for those with lesions of the tonsillar fossa/posterior tonsillar pillar (p= .0892), base of tongue (p= .9493), anterior tonsillar pillar/soft palate (p= .5909), and hypopharynx (p= .2282).

Conclusions.

The most important parameter that has an impact on local control after RT is T stage. Primary tumor volume also significantly influences the probability of local control in cancers of the supraglottis and glottis. © 2003 Wiley Periodicals, Inc. Head Neck 25: 535–542, 2003
Myofibroblastoma of the larynx: A study of two cases
Authors: MacGregor Allison R. , Batsakis John G. , El‐Naggar Adel K.
Published: June 2003

Background.

We describe, for the first time, the occurrence of two pure examples of spindle cell neoplasm with fibrous and smooth muscle differentiation in the larynx.

Materials and Method.

Tissue sections from both tumors stained with hematoxylin and eosin were reviewed. Immunophenotypic analysis using keratin, S‐100 protein, SMA, and h‐Caldesmon markers was performed.

Results.

Tumors were seen as raised submucosal nodules in the glottic region of two elderly male patients. Histopathologically, the lesions were unencapsulated and composed of spindle cells that manifested variable cellular anaplasia and expressed SMA and were negative for keratin, S‐100, and h‐Caldesmon.

Conclusions.

We document histologically low‐grade malignant myofibroblastic tumors of the larynx. Complete excision is advised. © 2003 Wiley Periodicals, Inc. Head Neck 25: 606–611, 2003
The beverage maté: A risk factor for cancer of the head and neck
Authors: Goldenberg David , Golz Avishay , Joachims Henry Zvi
Published: June 2003

Background.

Maté is a tealike beverage consumed habitually in South America and among South Americans throughout the world. It is brewed from the dried leaves and stemlets of the perennial tree Ilex paraguariensis (yerba maté), a species that belongs to the Aquifoliaceae family. Maté consumption has been associated with an increased rate of oral, oropharyngeal, esophageal, and laryngeal cancers. The purpose of this study is to review the literature and discuss the role of Maté consumption as a risk factor for head and neck cancers.

Materials and Methods.

We performed a thorough review of the relevant literature linking maté consumption with head and neck cancer and the proposed carcinogenicity of maté. Case control studies on maté‐drinking populations and in vivo and in vitro studies on the carcinogenicity of maté were reviewed. The populations included in many of these studies also used alcohol and tobacco products, confounding the influence of maté as an independent risk factor.

Results.

Evidence in the literature suggests that maté consumption is carcinogenic and plays a role in the development of cancers of the oral cavity, pharynx, larynx, and esophagus.

Conclusions.

The exact mechanism of carcinogenesis of maté is unknown. Both chemical and thermal carcinogenesis mechanisms have been suggested. Available information suggests that maté drinking is a risk factor for upper aerodigestive tract cancer. © 2003 Wiley Periodicals, Inc. Head Neck 25: 595–601, 2003
Degradation patterns of different adhesives and bonding procedures
Authors: Hashimoto Masanori , Ohno Hiroki , Sano Hidehiko , Kaga Masayuki , Oguchi Haruhisa
Published: June 2003

Various types of resin adhesives and procedures are available in the clinical field, so comprehensive understanding of degradation is required for each material and bonding procedure. The objective of this study was to investigate the bond durability for different adhesives and bonding procedures. Resin–dentin bonded beams were prepared with the use of two adhesives (One‐Up Bond F/self‐etching primer system and One Bond/total‐etch adhesive) and two experimental groups for the bonding procedure (wet and dry bonding of the total‐etch adhesive). Those samples were soaked in water for 24 h(control), 6 and 12 months. After the water immersion, the bond strengths were measured by the microtensile bond test, and subsequently fractography was performed with the use of SEM. Statistically significant reduction of the bond strength (p < 0.05) was apparent after 12 months of water exposure in the range 22–48% of the control. The bonding resin was eluted from the hybrid layer of the self‐etching and the total‐etch adhesives for the wet bonding. Micromorphological alterations were found due to the hydrolysis of collagen fibrils with the total‐etch adhesive for the dry bonding mode. These pathologic alterations were in accord with the bond strength. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 324–330, 2003
Mechanical evaluation of a porous bone graft substitute based on poly(propylene glycol‐co‐fumaric acid)
Authors: Hile David D. , Kirker‐Head Carl , Doherty Stephen A. , Kowaleski Michael P. , McCool John , Wise Donald L. , Trantolo Debra J.
Published: June 2003

A porous, resorbable polymer composite based on poly(propylene glycol‐co‐fumaric acid) (PPF) was mechanically evaluated in vitro for use as a bone graft substitute and fracture fixative. The test material created a dynamic system capable of initially providing mechanical integrity to bony voids and a degradative mechanism for ingrowth by native bone. The unsaturated polymer, PPF, was crosslinked in the presence of effervescent agents to yield a porous microstructure upon curing. An in vitro degradation study first assessed the temporal mechanical properties of the test material. This research was followed by an ex vivo study using a long‐bone osteotomy model to characterize the mechanics of fixation. Results showed the initial compressive strength of the cross‐linked PPF system was comparable to cancellous bone. The rate of strength loss was commensurate with the predicted mechanical recovery of healing bone with analogous results in a composite that comprised also 25% (by weight) autograft. Mechanical testing in the long‐bone model demonstrated that PPF‐based bone‐graft substitute increased the flexural strength of K‐wire stabilized osteotomies. These results suggest that this type of bone graft substitute may have clinical utility in the stabilization of complex tubular bone fractures. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 311–317, 2003
Adsorption of parotid saliva proteins and adhesion of Streptococcus mutans ATCC 21752 to dental fiber‐reinforced composites
Authors: Tanner Johanna , Carlén Anette , Söderling Eva , Vallittu Pekka K.
Published: June 2003

The use of fiber‐reinforced composites (FRC) in dentistry has increased during recent years. In marginal areas of crowns and removable partial dentures the fibers may become exposed and come into contact with oral tissues, saliva, and microbes. To date, few articles have been published on oral microbial adhesion to FRCs. The aim of this study was to compare different FRCs, their components, and conventional restorative materials with respect to S. mutans ATCC 21752 adhesion and adsorption of specific S. mutans binding proteins. Surface roughness of the materials was also determined. Four different FRCs, a restorative composite, and a high‐leucite ceramic material were studied. Polyethylene FRC was found to be significantly rougher than all other materials. Aramid FRC also showed higher surface roughness in comparison with all materials but polyethylene FRC. Without a saliva pellicle, adhesion of S. mutans coincided with surface roughness and polyethylene and aramid FRC promoted S. mutans adhesion better than the other smoother materials. In the presence of salivary pellicle, ceramic and polyethylene FRC bound more bacteria than the other materials studied. Higher quantities of S. mutans binding proteins in the pellicles may in part account for the higher S. mutans adhesion to saliva‐coated ceramic and polyethylene FRC. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 391–398, 2003
The effect of 30% hydrogen peroxide on the color of compomers
Authors: Kwon Y. H. , Kwon T. Y. , Kim H. I. , Kim K. H.
Published: June 2003

The interaction between bleaching agents and recently introduced compomers has several issues that need to be explored, including morphology and mechanical properties. To investigate the effect of 30% hydrogen peroxide, a bleaching agent, on the color of compomers, three compomers (Compoglass F, Elan, and F2000) were polymerized, bleached up to 120 h, and then measured to determine the reflectance of the specimen during the bleaching process. Color differences were evaluated from the reflectance and color values that were represented by CIE L*a*b* values. Compomers stored in distilled water were used as a source of reference. Teeth were also used for comparison. Color differences for both the tested teeth and compomers and different periods of bleaching and soaking in distilled water showed statistically significant difference (p < 0.0001). Among the tested compomers, Compoglass F demonstrated the highest color difference. In addition, the color differences were maximal during the first 24 h. After 24 h, the color difference increased nearly linearly. Compomers stored in both a bleaching agent and distilled water did not exhibit much color difference between them. However, the color difference between teeth and compomers was considerable. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 306–310, 2003
Design and evaluation of novel blood incubation systems for in vitro hemocompatibility assessment of planar solid surfaces
Authors: Streller U. , Sperling C. , Hübner J. , Hanke R. , Werner C.
Published: June 2003

Success in the development of hemocompatible biomaterials depends on adequate equipment and procedures for standardized analysis of blood–materials interactions in vitro. In view of the limited standard of knowledge on that important aspect, two novel incubation systems were designed, built, and evaluated for the in vitro assessment of the hemocompatibility of planar solid surfaces: A screening setup was introduced for the comparison of up to 12 different samples. A perfusion setup was developed to model the directed blood flow in the vascular system during incubation by a recirculation circuit, allowing the variation of the wall shear rate at the sample surface. The incubation procedures utilized freshly drawn, heparinized whole human blood. Hemocompatibility in terms of selected aspects of coagulation, thrombogenicity, and immune responses was quantified through plasma levels of characteristic molecules (immunoassays), cell counting, and analysis of adherent cells and fibrin formation (scanning electron microscopy), respectively. Prevention of blood–air contact and mechanical stress, constant temperature and blood pH during incubation, and the suitable choice of reference materials were found to be crucial for reliable testing. Considering those requirements, screening and perfusion system both provided sensitive discrimination between a given set of planar solid surfaces. In conclusion, the suggested methods for an in vitro hemocompatibility assessment permit versatile, sensitive, and efficient analysis of important blood–material interactions despite the unavoidable variability of blood characteristics in different experiments. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 379–390, 2003
Effect of chemical etching and aging in boiling water on the corrosion resistance of nitinol wires with black oxide resulting from manufacturing process
Authors: Shabalovskaya S. , Rondelli G. , Anderegg J. , Simpson B. , Budko S.
Published: June 2003

The effect of chemical etching in a HF/HNO3 acid solution and aging in boiling water on the corrosion resistance of Nitinol wires with black oxide has been evaluated with the use of potentiodynamic, modified potentiostatic ASTM F746, and scratch tests. Scanning‐electron microscopy, elemental XPS, and Auger analysis were employed to characterize surface alterations induced by surface treatment and corrosion testing. The effect of aging in boiling water on the temperatures of martensitic transformations and shape recovery was evaluated by means of measuring the wire electroresistance. After corrosion tests, as‐received wires revealed uniformly cracked surfaces reminiscent of the stress‐corrosion‐cracking phenomenon. These wires exhibited negative breakdown potentials in potentiostatic tests and variable breakdown potentials in potentiodynamic tests (− 100 mV to + 400 mV versus SCE). Wires with treated surfaces did not reveal cracking or other traces of corrosion attacks in potentiodynamic tests up to + 900–1400‐mV potentials and no pitting after stimulation at + 800 mV in potentiostatic tests. They exhibited corrosion behavior satisfactory for medical applications. Significant improvement of corrosion parameters was observed on the reverse scans in potentiodynamic tests after exposure of treated wires to potentials > 1000 mV. In scratch tests, the prepared surfaces repassivated only at low potentials, comparable to that of stainless steel. Tremendous improvement of the corrosion behavior of treated Nitinol wires is associated with the removal of defect surface material and the growth of stable TiO2 oxide. The role of precipitates in the corrosion resistance of Nitinol—scratch repassivation capacity in particular—is emphasized in the discussion. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 331–340, 2003
Fatigue testing and performance of acrylic bone‐cement materials: State‐of‐the‐art review
Authors: Lewis Gladius
Published: June 2003

Over the past three decades or so, a very large volume of literature has been generated on the impact of an assortment of variables on the fatigue lifetimes of a large number of acrylic bone‐cement formulations. In the present article, this literature is examined critically to reveal areas of agreement, areas of disagreement, as well as a welter of underexplored and unexplored topics. For example, there is unanimity of support for the notion that an increase in the molecular weight of the powder constituents or the fully cured cement leads to an increase in the cement's fatigue life, whereas there is disagreement as to whether vacuum mixing the cement constituents leads to an increase in the fatigue life of the fully cured cement (relative to the hand‐mixed counterpart). Among the underexplored topics is systematic study of the effect of test frequency on the fatigue results, whereas determination of the optimal concentration of the antibiotic in an antibiotic‐loaded cement is an example of the unexplored topics. It is pointed out that resolving the controversies, addressing the underexplored topics, and filling the lacunae will allow comprehensive evaluations of acrylic bone‐cement materials to be made. This enhanced body of knowledge will prove invaluable in the continued use of acrylic bone cement as the anchoring agent in cemented arthroplasties. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 457–486, 2003
Effect of admixed high‐density polyethylene (HDPE) spheres on contraction stress and properties of experimental composites
Authors: Ferracane J. L. , Ferracane L. L. , Braga R. R.
Published: June 2003

Additives that provide stress relief may be incorporated into dental composites to reduce contraction stress (CS). This study attempted to test the hypothesis that conventional fillers could be replaced by high‐density polyethylene (HDPE) spheres in hybrid and nanofill composites to reduce CS, but with minimal effect on mechanical properties. Nanofill and hybrid composites were made from a Bis‐GMA/TEGDMA resin having either all silica nanofiller or 75 wt.% strontium glass + 5 wt.% silica and replacing some of the nanofiller or the glass with 0%, 5% (hybrid only), 10% or 20 wt.% HDPE. The surface of the HDPE was either left untreated or had a reactive gas surface treatment (RGST). Contraction stress (CS) was monitored for 10 min in a tensilometer (n = 5) after light curing for 60 s at 390 mW/cm2. Other specimens (n = 5) were light cured 40 s from two sides in a light‐curing unit and aged 1 d in water before testing fracture toughness (KIc), flexure strength (FS), and modulus (E). Results were analyzed by ANOVA with Tukey's multiple comparison test at p < 0.05. There was no difference between composites with RGST and untreated HDPE except for FS‐10% HDPE hybrid (RGST higher). An increased level of HDPE reduced contraction stress for both types of composites. Flexure strength, modulus (hybrid only), and fracture toughness were also reduced as the concentration of HDPE increased. SEM showed evidence for HDPE debonding and plastic deformation during fracture of the hybrid composites. In conclusion, the addition of HDPE spheres reduces contraction stress in composites, either through stress relief or a reduction in elastic modulus. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 318–323, 2003
Endotoxin contamination in wound dressings made of natural biomaterials
Authors: Nakagawa Y. , Murai T. , Hasegawa Chie , Hirata M. , Tsuchiya T. , Yagami T. , Haishima Y.
Published: June 2003

Contamination by endotoxin of nine kinds of wound dressings made of natural biomaterials (calcium alginate, collagen, chitin, and poly‐L‐leucine) was examined with the use of water extracts. By applying the Limulus amoebocyte lysate (LAL) test, high concentrations of endotoxin were detected in extracts from three kinds of products made of calcium alginate. These extracts evoked fever in rabbits and induced the release of a proinflammatory (pyrogenic) cytokine, interleukin‐6 (IL‐6), from human monocytic cells (MM6‐CA8). The effects disappeared when the extracts were treated with endotoxin‐removing gel column chromatography or with an endotoxin antagonist, B464, confirming that the contaminating pyrogen was endotoxin. A noteworthy finding was that one of the endotoxin‐containing extracts showed very weak IL‐6‐inducibility in human monocytic cells in contrast to its high pyrogenicity to rabbits. The discrepancy could be explained based on differences between humans and rabbits in sensitivity to the endotoxin, because the extract showed higher proinflammatory‐cytokine (TNF‐α)‐inducibility in rabbit whole‐blood cells (WBCs) than human WBCs. The results suggest that the LAL test is a useful method of detecting endotoxin contamination in wound dressings and the MM6‐CA8 assay is a good supplement to the LAL test for evaluating pyrogenicity in humans accurately. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 347–355, 2003
Titanium–cell interaction: Analysis of gene expression profiling
Authors: Carinci F. , Volinia S. , Pezzetti F. , Francioso F. , Tosi L. , Piattelli A.
Published: June 2003

Titanium and its alloys are used worldwide in surgery. Dental implants, screws and plates, prostheses, and surgical instruments are made with titanium‐based metals. The favorable characteristics that make this material desirable for implantation are (a) mechanical proprieties and (b) biocompatibility. The latter has been demonstrated by in vivo studies with animal models and clinical trials over a 40‐year period. However, the exact effect of titanium on cells is still not well characterized. Expression profiling by DNA microarray is a new molecular technology that allows the analysis of gene expression in a cell system. Several genes whose expression was significantly up‐ or downregulated in an osteoblast‐like cell line (MG‐63) on titanium were identified with the use of DNA microarrays containing 19,200 genes. The differentially expressed genes are associated with a broad range of functional activities, including apoptosis, vesicular transport, and structural function. It was also possible to detect some genes whose function is unknown. The data reported are, to the author's knowledge, the first genetic portrait of titanium–cell interaction. They may help to provide a better understanding of the molecular mechanisms of titanium biocompatibility and serve as a model for studying the biocompatibility of other materials. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 341–346, 2003
Frontal sinus and skull bone defect obliteration with three synthetic bioactive materials. A comparative study
Authors: Peltola Matti J. , Aitasalo Kalle M. J. , Suonpää Jouko T. K. , Yli‐Urpo Antti , Laippala Pekka J. , Forsback Ari‐Pekka
Published: June 2003

Three synthetic bioactive materials were studied in an experimental model to compare their usability in a frontal sinus and a skull bone defect obliteration. Bioactive glass number 9 (BAG1), bioactive glass number 13 (BAG2), and hydroxyapatite (HA) granules were investigated. BAG1 and HA granules have been previously tested clinically. The clinical usefulness of BAG2 granules has not been tested. Upper bony walls of 45 Elco rabbits' frontal sinuses were drilled open from four separate holes with the use of a standard method. The skull bone defects and the sinuses in frontal bone were filled with BAG1 or BAG2 on one side, and with HA on the other side. Two parallel posterior defects were covered with a pedicled periosteum flap, and two anterior defects with a free flap. The resorption of materials, new bone, and fibrous‐tissue formation were observed with a histomorphometric method at 1, 3, and 6 months postoperatively. Scanning‐electron microscopy (SEM) and Fourier‐transform infrared spectroscopy (FTIR) were done at 6 months. In histomorphometry, the new bone formation increased with all the investigated materials throughout the study (p < 0.001), but the results showed higher new bone formation in the defects filled with BAG1 than in corresponding BAG2‐ or HA‐ filled defects. New bone formation and resorption of materials were faster in defects covered by pedicled than by free periosteum flaps (p < 0.001). Intimate contact between the used materials and new bone was confirmed by SEM. FTIR analysis of bone produced by BAG1 and BAG2 was of the same type as natural frontal bone. BAG2 can be manufactured in various shapes, and thus, could possibly be used in clinical conditions requiring a special anatomical implant shape. However, more research is needed regarding this property of BAG2. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 364–372, 2003
Microleakage and interfacial morphology of self‐etching adhesives in class V resin composite restorations
Authors: Osorio Raquel , Toledano Manuel , de Leonardi Guillermo , Tay Franklin
Published: June 2003

The purpose of the study was to evaluate the marginal leakage of three adhesive systems in Class V resin composite restorations. Two adhesive systems containing acidic primers: Clearfil SE Bond (CSEB) and Etch & Prime 3.0 (E&P), were compared with a conventional water‐based primer: Scotchbond Multipurpose Plus (SBMP). Class V cavities were made at the cementum–enamel junction of extracted human molars, which were then divided between three groups. One of the adhesive systems was applied to each group following manufacturers' instructions. Composite restorations were placed, light cured for 40 s, and polished. Specimens were then immersed in a solution of 2% basic fuchsin dye for 24 h. Longitudinal sections were obtained and studied with a stereomicroscope for assessment of the microleakage according to the degree of dye penetration (scale of 0–3). Data were analyzed by Kruskal‐Wallis one‐way ANOVA, Mann‐Whitney tests, and the Wilcoxon matched‐pairs signed rank test. Two specimens for each group were analyzed by scanning‐electron microscopy (SEM). Bonded interfaces of dentin were also examined by transmission‐electron microscopy (TEM). On enamel, there were no significant differences between the three groups. On dentin, CSEB showed the lowest dye penetration values among the three adhesive systems. SEM and TEM studies showed hybrid layer and resin tag formations in all groups. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 399–409, 2003
Reduction of wear in total hip replacement prostheses by amorphous diamond coatings
Authors: Lappalainen Reijo , Selenius Mikko , Anttila Asko , Konttinen Yrjö T. , Santavirta Seppo S.
Published: June 2003

Wear‐debris–induced periprosthetic bone loss and aseptic loosening is regarded as the main long‐term problem of total hip replacements (THRs). In this study the amount of wear debris from articulating surfaces of THRs was reduced so as to be close to negligible by the use of high‐quality amorphous diamond (AD) coatings deposited by pulsed plasma arc techniques. The wear rates determined in a commercial hip simulator for 15 million walking cycles (corresponding to about 15 years of clinical use) in serum lubrication were even 1,000,000 times lower than the clinical values for conventional THRs (polyethylene–metal or metal–metal pairs). Elimination of wear debris and good biomechanical performance should provide a substantial improvement of the clinical longevity of the THRs. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 410–413, 2003
Bonded interface between a self‐curing resin and dentin primed with a metalloprotein
Authors: Taira Yohsuke , Matsumura Hideo , Atsuta Mitsuru
Published: June 2003

The purpose of this study was to investigate adhesive bonding between a self‐curing luting agent and dentin conditioned with a metalloprotein in terms of resin–dentin hybridization and interfacial polymerization. Of the six experimental primers containing bovine heart cytochrome c (BHCC), three contained 2‐hydroxyethylmethacrylate (HEMA) and the remaining three did not. The self‐curing luting agent used consisted of methyl methacrylate (MMA) and tri‐n‐butylborane (TBB) with or without 4‐methacryloyloxyethyl trimellitate anhydride (4‐META). Bovine dentin surfaces were etched with 10wt% phosphoric acid, primed, and then bonded with stainless steel rods. After 24 h of water storage, the optimum bond strength was obtained with the 4‐META/MMA‐TBB luting agent and the aqueous primer contained 0.1 μmol/g BHCC and 35wt% HEMA. Microscopic observations showed continuity among the luting agent, the hybridized dentin, and the dentin substrate. A model experiment suggested that BHCC accelerates the polymerization of the 4‐META/MMA/HEMA mixture from the hybridized dentin. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 414–418, 2003
Tantalum as a buffer layer in diamond‐like carbon coated artificial hip joints
Authors: Kiuru Mirjami , Alakoski Esa , Tiainen Veli‐Matti , Lappalainen Reijo , Anttila Asko
Published: June 2003

The acid resistance of tantalum coated and uncoated human hip joint prostheses was studied with commercial CrCoMo acetabular cups. The samples were exposed to 10% HCl solution and the quantities of dissolved Cr, Co, and Mo were measured with proton‐induced X‐ray emission (PIXE). The absolute quantities were obtained with the use of Cr and Se solution standards. Tantalum coatings (thicknesses 4–6 μm) were prepared in vacuum with magnetron sputtering. Tantalum coating decreased the corrosion rate by a factor of 106. As a spinoff from recent wear tests on artificial hip joints it was shown that tantalum has excellent mechanical properties as an intermediate layer of diamond‐like carbon (DLC) coatings. When tantalum was tested together with DLC on three metal‐on‐metal hip joint pairs in a hip simulator, no observable defects occurred during 15 million walking cycles with a periodic 50–300‐kg load (Paul curve). © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 425–428, 2003
Inverse relationship between tensile bond strength and dimensions of bonded area
Authors: Escribano Nuria I. , Del‐Nero Maria O. , de la Macorra Jose C.
Published: June 2003

It is a known fact that there is a relationship between magnitude of bonded area and laboratory tensile test results. This relationship has been described for a range of areas between 1 and 10 mm2, in extracted, nonperfused teeth. The aim of this study is to test this relationship in perfused teeth, with bonded areas ranging from 0.7 to 110.9 mm2. Dentin of 92 sound third human molars was exposed and perfused, and three groups of bonded areas (BA) were delimited: small (0.69–1.89 mm2), medium (8.66–19.54 mm2), and large (58.91–110.86 mm2). Tensile bond strength (TBS) of three adhesive restorative systems was found. The best nonlinear curve estimation was searched (SPSS 9.0) between TBS and BA, for each and all materials. The best estimation was, for all materials, TBS = 4.17 + 10.35/BA (p < 0.0001). © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 419–424, 2003
Difference in polymerization color changes of dental resin composites by the measuring aperture size
Authors: Lee Yong‐Keun , Lim Bum‐Soon , Kim Cheol‐We
Published: June 2003

The objective of this study was to evaluate the influence of the illuminating/viewing aperture diameter of 11 mm/8 mm and 3 mm/3 mm and measuring geometry on the color and polymerization color changes of dental resin composites. Color of resin composites of 12 mm in diameter was measured on a reflection spectrophotometer with SCE and SCI geometry under D65 illumination. Before polymerization, difference in the three‐color coordinates by the material was prominent in spite of the fact that the shade designation of all materials was the same. After polymerization, L* value decreased in hybrid composites but not in packable composites, and changes in a* value were small. When the same aperture size was used, polymerization color change with the SCE was generally higher than those with the SCI. Measured color was different by the aperture size, and the color difference was 16.82–27.05 before polymerization and 20.09–28.51 after polymerization. General trends of polymerization color change were similar in both aperture sizes. Polymerization color changes with 3‐mm aperture size were higher than those with 8‐mm aperture size in hybrid resin composites in both geometries (p < 0.05); however, the color change was material dependent in the case of packable resin composites. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 373–378, 2003
Use of injectable calcium‐phosphate cement for the fixation of titanium implants: An experimental study in goats
Authors: Ooms E. M. , Wolke J. G. C. , van der Waerden J. P. C. M. , Jansen J. A.
Published: June 2003

This in vivo study evaluated the fixation of two types of titanium implants with the use of an injectable calcium‐phosphate (CaP) cement. The cement was either used to create a cement mantle (Type A implant) or as an additive to press‐fit placed titanium plasma sprayed implants (Type B implant). The implants were placed in trabecular bone of the medial femoral condyle of goats and left in place for 2 and 10 weeks. Mechanical evaluation of the implant fixation was done by torque testing. This showed that for the Type A implants the calcium‐phosphate cement's performance was significantly inferior (P < 0.05) to that of polymethylmethacrylate cement fixation. For the two‐week Type B implants a significant increase (P < 0.05) in failure load was found for calcium‐phosphate cemented implants compared with just press‐fitted Type B implants. Histological evaluation revealed that for Type A implants, failure during torque testing occurred at the implant–cement interface. In contrast, for Type B implants, failure occurred in the bone–implant interface for press‐fit–placed devices and in the cement layer for CaP‐cemented devices. Further, the CaP cement was found to be overgrown with new formed bone already after 2 weeks of implantation. The cement showed resorption due to regular bone remodeling. On the basis of these observations, it was concluded that the use of injectable CaP cement might facilitate earlier loading of press‐fit inserted titanium implants. Nevertheless, the results have to be confirmed in dynamical mechanical as well as loaded in vivo studies. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 447–456, 2003
A formula for the number of Steiner quadruple systems on 2npoints of 2‐rank 2n−n
Authors: Tonchev Vladimir D.
Published: June 2003

Assmus [1] gave a description of the binary code spanned by the blocks of a Steiner triple or quadruple system according to the 2‐rank of the incidence matrix. Using this description, the author [13] found a formula for the total number of distinct Steiner triple systems on 2n−1 points of 2‐rank 2n‐n. In this paper, a similar formula is found for the number of Steiner quadruple systems on 2npoints of 2‐rank 2n‐n. The formula can be used for deriving bounds on the number of pairwise non‐isomorphic systems for largen, and for the classification of all non‐isomorphic systems of small orders. The formula implies that the number of non‐isomorphic Steiner quadruple systems on 2npoints of 2‐rank 2n‐ngrows exponentially. As an application, the Steiner quadruple systems on 16 points of 2‐rank 12 are classified up to isomorphism. © 2003 Wiley Periodicals, Inc. J Combin Designs 11: 260–274, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jcd.10036
A lower bound on the number of Semi‐Boolean quadruple systems
Authors: Buratti Marco , Del Fra Alberto
Published: June 2003

A Steiner quadruple system of order 2nisSemi‐Boolean(SBQS(2n) in short) if all its derived triple systems are isomorphic to the point‐line design associated with the projective geometryPG(n−1, 2). We prove by means of explicit constructions that for anyn, up to isomorphism, there exist at least 2⌊ 3(n−4)/2⌋regularand resolvable SBQS(2n). © 2003 Wiley Periodicals, Inc. J Combin Designs 11: 229–239, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jcd.10050
CTGF/Hcs24, hypertrophic chondrocyte‐specific gene product, interacts with perlecan in regulating the proliferation and differentiation of chondrocytes
Authors: Nishida Takashi , Kubota Satoshi , Fukunaga Tomohiro , Kondo Seiji , Yosimichi Gen , Nakanishi Tohru , Takano‐Yamamoto Teruko , Takigawa Masaharu
Published: June 2003

Connective tissue growth factor/hypertrophic chondrocyte‐specific gene product 24 (CTGF/Hcs24) plays important roles in the control of the proliferation and differentiation of chondrocytes in vitro. To clarify the mechanisms of regulation by CTGF/Hcs24 with respect to cartilage metabolism, we investigated the interaction between CTGF/Hcs24 and heparan sulfate proteoglycan perlecan. An immunofluorescence study showed that CTGF/Hcs24 was colocalized with heparan sulfate and perlecan in human chondrosarcoma‐derived chondrocytic cell line HCS‐2/8 in vitro. Northern blot analysis showed that perlecan, syndecan‐1, ‐2, and ‐4 transcripts were detected in HCS‐2/8 cells. Particularly, expression of the perlecan gene increased markedly in HCS‐2/8 cells by recombinant CTGF/Hcs24 (rCTGF/Hcs24) treatment. We also found that CTGF/Hcs24 interacted with perlecan from HCS‐2/8 cells in vitro. Furthermore, CTGF/Hcs24‐stimulated gene expression of the aggrecan gene, as well as DNA/proteoglycan synthesis, was diminished when HCS‐2/8 cells were pretreated with heparinase, indicating that the effects of CTGF/Hcs24 on chondrocytes occurred through the interaction between CTGF/Hcs24 and heparan sulfate on the cells. An in vivo study using mouse growth plate revealed that CTGF/Hcs24 produced by hypertrophic chondrocytes was localized from the proliferative to the hypertrophic zone, whereas perlecan was predominantly localized in the prehyphertrophic zone. Consistent with such findings in vivo, the binding of 125I‐rCTGF/Hcs24 to maturing chondrocytes was at higher levels than that to chondrocytes in hypertrophic stages. These findings suggest that CTGF/Hcs24 produced in the hypertrophic region may act on chondrocytes in the proliferative and maturative zone via some heparan sulfate proteoglycan, such as perlecan. J. Cell. Physiol. 196: 265–275, 2003. © 2003 Wiley‐Liss, Inc.
Pro‐apoptotic ASY/Nogo‐B protein associates with ASYIP
Authors: Qi Bing , Qi Yipeng , Watari Akihiro , Yoshioka Naohisa , Inoue Hirokazu , Minemoto Yuzuru , Yamashita Katsumi , Sasagawa Toshiyuki , Yutsudo Masuo
Published: June 2003

We have previously shown that ectopic expression of the ASY/Nogo‐B gene induced apoptosis in various cancer cell lines. Nogo‐A, a splice variant of the ASY, has been reported to have an inhibitory effect on neuronal regeneration in the central nervous system. To investigate the mechanism of ASY‐induced apoptosis or inhibition of neuronal regeneration, we cloned a cDNA for the ASY‐interacting protein from the human cDNA library using the yeast two‐hybrid method, and obtained a cDNA we designated as ASYIP. The ASYIP protein contains two hydrophobic regions and a double lysine endoplasmic reticulum (ER) retrieval motif at its C‐terminus, which was shown to be identical to RTN3, a reticulon family protein of unknown function. We showed that ASY and ASYIP proteins formed a complex also in human cells. Mutational analysis indicated that both of the hydrophobic regions of the ASYIP protein were required for the association. By immunofluorescence analysis, the ASYIP protein was shown to be co‐localized with ASY in the ER. Characterization of the ASYIP gene may be very useful in clarifying the mechanism of ASY‐induced apoptosis or Nogo‐involved inhibition of neuronal regeneration in the central nervous system. J. Cell. Physiol. 196: 312–318, 2003. © 2003 Wiley‐Liss, Inc.