bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pulp capping with synthetic hydroxyapatite in human premolars
Authors: Frank R. M. , Wiedemann P. , Hemmerle J. , Freymann M. 
Published: May 2005

AbstractClassically, calcium hydroxide is used as a pulp capping agent in humans to form a dentinal bridge over vital dental pulp tissue. The aim of the present study was to determine whether synthetic hydroxyapatite could be used as a substitute. For this purpose, pulp capping with microsized hydroxyapatite (mean size = 38 nm ± 15 nm) was done under lacal anesthesia in 12 normal premolars, to be extracted for orthodontic purposes form 12 different young patients, having given their informed consent. Clinically, the healing was uneventful in all patients, having given their informed consent. Clinically, the healing was uneventful in all patients. Half of the teeth were extracted at 3 months and the other half at 6 months. The pulps were studied under light microscopy and under scanning and transmission electron microscopy using nondecalcified sections. In all cases, a continuous, well‐calcified bridge was observed and no inflammatory cells were present in the residual pulp. In some cases denticles containing some synthetic hydroxyapatite crystals were found in the radicular pulp. The calcified bridge was made up by osteodentine and near the pulp tubular dentine with a layer of predentine and odontoblasts were noted. Odontoblastic processes were lacated in deninal tubules and the intertubular dentine showed interwoven calcified collagen fibrils and hydroxyapatite crystals with a mean length of 0.1 μm along their c axis.
Fibroblast shape conformation to surface micromorphology
Authors: Meyle J. , von Recum A. F. , Gibbesch B. , Hüttemann W. , Schlagenhauf U. , Schulte W. 
Published: May 2005

AbstractFibroblasts in culture and in vitro have been shown to interact with certain surface morphological phenomena. It was the aim of the present study to determine cellular morphological interactions with surface grooves of subcellular dimensions. The silicon oxide layer of a wafer was photoetched, which resulted in a regular micromorphology with linear rectangular shaped microbars and microgrooves 1, 1.5, and 2 μm in diameter and distance from each other. Human fibroblasts were seeded on the sterile specimen and incubated for 48 h. Fluorescence microscopy of the plates revealed that all the cells were aligned parallel to the etched grooves on the test specimen, whereas on the controls the cells were randomly orientated. It could be demonstrated by scanning electron microscopy that single cels were flattened over the surface and conformed to the silicon microgrooves. This indicates that fibroblasts are orienting during adhesion and conform to the surface microtexture to gain a maximum contact area on the presented surface.
The effect of the addition of methylene blue on the fatigue strength of simplex P bone–cement
Authors: Davies Jeffrey P. , Harris William H. 
Published: May 2005

AbstractTo aid in cement removal during revision arthroplasty, it has been proposed to add methylene blue to bone cement to provide contrast between the cement and bone. However, it is essential that the fatigue strength of the cement not be reduced by the addition of the methylene blue. The effect of adding 1 mL of an aqueous 1% solution of methylene blue to one pack of Simplex P prepared in the standard fashion (uncentrifuged) was studied. We also measured the fatigue properties of centrifuged Simplex P with three different methylene blue preparations. We studied adding 1 mL of an aqueous 1% solution of methylene blue, 0.5 g of methylene blue powder, and 0.1 mL of a 10% solution of methylene blue per pack of Simplex P bone cement. Adding 1 mL of a 1% methylene blue solution to 40 g of Simplex P without centrifuging the cement after mixing produced a cement with a mean fatigue life comparable to the uncentrifuged Simplex P without the methylene blue. However, the fatigue data scatter was higher for the uncentrifuged methylene blue preparation. The optimum methylene blue impregnated cement preparation was produced by adding 1 mL of a 1% methylene blue solution to 40 g of Simplex P powder, mixing with chilled monomer, and centrifuging for 60 s. Sterile 1 mL vials of 1% methylene blue solution are available in the operating room. Thus the experienced surgeon can use a cement containing color to facilitate distinguishing cement from bone in cases needing revisions without weakening the cement.
Polypropylene IUCD retrieval fibers: Surface morphology, material properties, microbial attachment, and migration
Authors: Coughlin Robert W. , Vietn Robert F. , Dibenedetto Anthony T. 
Published: May 2005

AbstractHighly drawn and oriented polypropylene fibers used for the retrieval thread of the Cu‐7 intrauterine contraceptive device (IUCD) are compared as to surface morphology and crystallinity with polypropylene fibers prepared under different conditions. A series of experiments also demonstrates the colonization of the surface of polyolefin fibers by pathogenic bacteria that are often found in the human vagina. Moreover, it is demonstrated that the retrieval threads appear to encourage pathogenic bacteria to migrate across the surface of agar. The results also indicate that control of drawing and annealing can avoid the surface fibrillation and tendency to fail by separation into a bundle of multifilaments that are observed with the IUCD retrieval threads.
A silver‐sulfadiazine‐impregnated synthetic wound dressing composed of poly‐l‐leucine spongy matrix: An evaluation of clinical cases
Authors: Kuroyanagi Yoshimitsu , Kim Eikichi , Kenmochi Makoto , Ui Kenji , Kageyama Hiromi , Nakamura Motonobu , Takeda Akira , Shioya Nobuyuki 
Published: May 2005

AbstractThe management of severe burns requires the suppression of bacterial growth, particularly when eschar and damaged tissue are present. For such cases, silver sulfadiazine (AgSD) cream has been traditionally applied. This antibacterial cream, however, cannot be used in conjunction with a temporary wound dressing that is needed to promote healing. The authors developed a synthetic wound dressing with drug deliver capability for clinical use by impregnating a poly‐‐ spongy matrix with AgSD, which is released in a controlled, sustained fashion. In general, the dressing adhered firmly to the wound in the case of superficial second‐degree burns, and during the healing process it separated spontaneously from the re‐epithelialized surface. In the management of deep second‐degree burns where eschar and damaged tissue were present, the dressing had to be changed at intervals of 3 to 5 days until it adhered firmly to the wound. Once the dressing had firmly attached to the wound, it was left in place until it separated spontaneously from the re‐epithelialized surface. Dressing changes were fewer than with other treatments and the pain was effectively reduced. Cleansed wounds were effectively protected from bacterial contamination. Of 52 cases treated with this wound dressing, 93% (14/15) of superficial second‐degree burns, 75% (3/4) of deep second‐degree burns, 85% (6/7) of superficial and deep second‐degree burns, and 75% (12/16) of split‐thickness skin donor sites were evaluated as achieving good or excellent results.
Self‐reported signs and symptoms in breast implant patients with novel antibodies to silicone surface associated antigens [anti‐SSAA(x)]
Authors: Kossovsky Nir , Gornbein Jeffrey A. , Zeidler Michelle , Stassi John , Chun Grace , Papasian Nora , Nguyen Rachel , Ly Kahn , Rajguru Samir 
Published: May 2005

AbstractIn research animals, the immune adjuvant activity of silicone in eliciting antibodies to associated protein antigens is now well established. In humans, the immune adjuvant activity of silicone remains controversial. Clusters of data from various research groups are beginning to define the boundary conditions for future large epidemiological studies. In that spirit, this manuscript reports pilot clinical data from a serological study conducted 3 years ago and reported previously in this journal. Sera from a self‐selected symptomatic population of patients with breast implants were assayed for elevated concentrations of antibodies showing binding avidity to silicone surface associated antigens [anti‐SSAA(x)]. In that study of 249 patients, two distinct statistically significant subgroups were identified on the basis of the serological assay alone: patients without any elevated anti‐SSAA(x) (negative) and patients with elevated anti‐SSAA(x) (positive) (p < 0.001). In this study, a clinical survey returned by 226 of those patients was correlated with the previously acquired serological findings. The 11 most common clinical complaints reported by the 199 anti‐SSAA(x) negative patients and by the 27 anti‐SSAA(x) positive were compared and their frequencies analyzed. The 199 anti‐SSAA(x) negative patients, as a group, showed a lower frequency of a variety of signs and symptoms compared to the 27 anti‐SSAA(x) positive patients. Statistically significant differences were seen in three of the symptoms: fever, foot pain, and sleep disturbance (p < 0.05). In addition, the syndrome of fever in the absence of local chest pain was a significantly associated with anti‐SSAA(x) positivity (p < 0.001). © 1995 John Wiley & Sons, Inc.
Effects of precoating surface treatments on fatigue of Ti‐6Al‐4V
Authors: Eberhardt Alan W. , Kim Byeong S. , Rigney E. Douglas , Kutner Gerald L. , Harte Charles R. 
Published: May 2005

AbstractGrit blasting is a common procedure of roughening surfaces to promote physical attachment of porous coatings, but it has been shown to reduce fatigue strength. Shot peening is known to increase fatigue strength by inducing compressive surface stresses; however, it is not known how subsequent grit blasting affects these benefits. This study examines the endurance limits, Se, of ELI grade Ti‐6A1‐4V specimens under rotating cyclic bending, including polished (control); belted and beaded; belted, beaded, and grit blasted; and belted, beaded, shot peened, and grit blasted. Belting and beading resulted in a slight increase in Se; grit blasting caused a 15% reduction in Se from polished. Fifty percent of this reduction was recovered when shot peening preceded grit blasting, suggesting that residual compressive surface stresses, induced by peening, were not eliminated by the blast process. Roughness averages and RMS values did not correlate with Se trends. SEM results showed classical fatigue fractures, consistent with surface crack initiation. © 1995 John Wiley & Sons, Inc.
Biological materials fixed with an epoxy compound: Comparison of the effects with or without ionically bound heparin
Authors: Sung Hsing‐Wen , Shih Jeng‐Shiuan 
Published: May 2005

AbstractBiological materials have been used as prosthetic devices such as heart valves, vascular grafts, and pericardial patches. These biological materials have to be fixed with crosslinking reagents and sterilized subsequently before they can be implanted in humans. Recently, a new crosslinking reagent, epoxy compound, has been used to fix bioprostheses. In this fixation technique, heparin may be ionically bound on the tissue surface. It has been shown that the amount of heparin bound to the tissue surface is proportional to the quantity of protamine impregnated in the biological tissues. However, it is not known if the impregnation of protamine will affect the crosslinking density of the biological tissues. This study was designed to compare the crosslinking densities of the epoxy compound fixed biological tissues with or without heparinization. Fresh porcine aortic valves procured from a slaughter house were first impregnated in various concentrations of protamine sulfate (0, 0.5, 1.0, or 1.5%) for about 30 min. The porcine aortic valves were then crosslinked in a 4% epoxy compound solution (Denacol® EX‐313). The porcine samples were taken out at various elapsed fixation periods: 18, 25, 48, 72, 96, and 120 h. Finally, the crosslinked porcine aortic valves were heparinized in a 0.5% sodium heparin solution for about 1 h. The crosslinking densities of the porcine leaflet and the aortic wall of each sample were determined by measuring their shrinkage temperatures. It was revealed that the impregnation of various concentrations of protamine did not seem to significantly alter the shrinkage temperatures of the porcine leaflet and the aortic wall throughout the entire fixation process (p > 0.05). This indicated that the impregnation of protamine did not significantly change the crosslinking density of the biological tissues. However, it was found that protamine tended to discolor the tissue and to stiffen the porcine leaflet and the aortic wall. Although the impregnation of protamine did not seem to significantly alter the crosslinking density of the epoxy compound fixed biological tissues, the increase of the stiffness of the heparinized tissues may cause concerns in some clinical applications. © 1995 John Wiley & Sons, Inc.
Reinforced poly(L‐lactic acid) fibres as suture material
Authors: Lam K. H. , Nijenhuis A. J. , Bartels H. , Postema A. R. , Jonkman M. F. , Pennings A. J. , Nieuwenhuis P. 
Published: May 2005

AbstractIn this study, reinforced poly(L‐lactic acid) (PLLA) fibers made by a dry‐spinning/hot‐drawing process were evaluated for use as a suture. The initial tensile strength of the PLLA fibers was lower than the initial tensile strength of the commercially available sutures: PDS, VicrylTM, silk, and Ethilon™. However, after 12 weeks immersion in a phosphate saline buffer at 37°C, PDS sutures have lower tensile strength than PLLA sutures and the tensile strength of Vicryl™ was unmeasurable because of fragmentation. Initially, PLLA fibers distinegrated into fibrils during degradation triggering an inflammatory response comparable to degradable multifilament sutures. However, the intensity of the inflammatory response against the PLLA fibers decreased and after 80 weeks implantation in the muscle layer of the abdominal wall of rats it was comparable to the one against Ethilon™. The inflammatory response against Ethilon™, which is considered to be nondegradable, increased in the same period, probably due to the change in shape. In practice, the handling characteristics of PLLA sutures are superior to the monofilament sutures like PDS and EthilonTM and comparable with the multifilament sutures like VicrylTM and silk. The knot security, but this remains to be investigated. It is concluded that dry‐spun/hot‐drawn (reinforced) PLLA fibers have the potential for use as long‐term degradable suture material. © 1995 John Wiley & Sons, Inc.
Effect of corrosion products (neodymium iron boron) on oral fibroblast proliferation
Authors: Evans R. D. , McDonald F. 
Published: May 2005

AbstractThe biological effects of the corrosion products of neodymium iron boron (Nd2Fe14B) magnets are largely unknown. The aim of this study was to identify the types of corrosion product and to evaluate the effect of the corrosion products (CP) of Nd2Fe14B magnets on the proliferation of human oral mucosal fibroblasts. Uncoated Nd2Fe14B magnets were stored in saline at 37°C for 6 months and the corrosion products collected. 100 μL of a cell suspension (human oral mucosal fibroblasts [4 × 104 cell/mL]) was aliquoted into 72 wells of a 96‐well plate, the remaining plates receiving culture medium only. After 12 h incubation at 37°C, each well then received 100 μL of either (A) culture medium, (B) 100% CP, (C) 50%, or (D) 0% CP. The plates were reincubated at 37°C for a further 48, 96 or 144 h. Fibroblast proliferation was assessed using the methylene blue uptake/elution technique. The compounds in the corrosion product were examined using quantitative X‐ray analysis. Statistical analysis (ANOVA, Bonferroni's test 0.05, SAS v 6.04), showed that at each time point, the cell numbers in groups B, C. and D were significantly lower than group A. Within groups B, C, and D no significant differences were found, despite the suggestion of a dose response effect. Fibroblast proliferation in the presence of corrosion products was significantly lower than with culture medium. Fibroblast proliferation did occur in the presence of 0, 50, and 100% CP. The actual corrosion products appeared to be salts of iron but 3.2% (±0.6) of neodymium chloride (NDCl3) was found. © 1995 John Wiley & Sons, Inc.
Comparison of diametral shrinkage of centrifuged and uncentrifuge simplex P® bone cement
Authors: Davies Jeffrey P. , Harris William H. 
Published: May 2005

AbstractReducing the porosity of bone cement substantially strengthens the cement in fatigue. However, concern has been raised that reducing the porosity of the cement would increase the shrinkage of the cement and thus compromise the cement‐bone interface. We measured diametral shrinkage of cement mantles prepared with and without centrifugation of the cement. Four cement preparations (centrifuged and uncentrifuged mixed with monomer at either room temperature or 0°C) were used to form cement mantles of four different thicknesses (2, 4, 6, and 8 mm) around a stainless steel rod. We conclude that porosity reduction dramatically increases the fatigue strength of bone cement without substantially changing the diametral dimensions of the polymerized cement when studied in the shape and volume of a cement mantle that would be used for total hip replacement. © 1995 John Wiley & Sons, Inc.
Production of L‐tryptophan in submerged culture
Authors: Malin Bernard , Westhead Jack 
Published: May 2005

AbstractA strain of C. purpurea has been isolated which will produce L‐tryptophan from indole in submerged culture.The L‐tryptophan produced is extracellular and in a free form.Levels of up to 1·5 mg/ml of L‐tryptophan have been obtained.
An apparatus for the culture of algae under controlled conditions
Authors: Fogg G. E. , Smith W. E. E. , Miller J. D. A. 
Published: May 2005

AbstractAn apparatus is described in which large numbers of algal cultures can be maintained under the following conditions: (1) Constant temperature within the range 5 to 70°C, four different temperatures being maintained simultaneously; (2) uniform illumination at intensities up to 20,000 metre‐candles; (3) continuous shaking at variable speed; and (4) aeration under aseptic conditions with mixtures of up to four different gases in any desired proportions.Among other features, thermoregulator heads, flow‐meters and heaters for sterile filters, of improved design are described.To illustrate the use of the apparatus, data showing the effects of light intensity and temperature on the growth of Monodus subterraneus are presented.
Microbiological evaluation of peptones
Authors: Kheshgi Saeed , Saunders Richard 
Published: May 2005

AbstractInformation on a reliable method for determining the nutritive value of existing and experimental peptones is lacking in the literature. To overcome this handicap, a method for comparative evaluation of microbiological peptones has been developed.The method is based on measuring the growth of eight carefully selected, fastidious, test cultures. The cultures are grown in presence and absence of yeast extract in an inorganic basal medium containing test peptone and a low and high level of glucose.Statistical analysis of replicate peptone evaluations of six peptones, conducted over a period of six months, shows that 95 per cent confidence limits for this method are ± 2·5 to 7·9 per cent of the mean.Four criteria are employed for determining the overall performance of 12 widely used, commercial peptones.The method is very sensitive for detecting differences between batches of commercial peptones. With the aid of this method a new peptone ‘N‐Z‐Amine YT’ has been developed. Considering performance and relative cost, this peptone is the most economical of the peptones evaluated.
Batch centrifuge scale‐up for virus processing
Authors: Patrick William C. , Freeman Robert R. 
Published: May 2005

AbstractThe mathematical relationship between the throughput of a batch centrifuge and its mechanical characteristics has been applied to the scale‐up of one of the steps in virus processing for possible application to the production of vaccines and similar antigens. Slurries that contained a test virus were purified in a laboratory centrifuge. The Q/Σ relationship, developed by Ambler, was used to predict the operating conditions of a larger centrifuge in order to achieve the same clarification of slurry as that produced in the laboratory centrifuge. A correlation between conditions of centrifugation and amount of virus removed from the feed to the centrifuge shows that there is a well‐defined Q/Σ value at which significant concentrations of the test virus are sedimented.
The evaluation of a process for the preparation of co‐enzyme A from yeast
Authors: Reece M. C. , Donald M. B. , Crook E. M. 
Published: May 2005

AbstractA process is described for the extraction of co‐enzyme A from dried yeast. It involves cold water extraction, charcoal adsorption followed by pyridine elution, preparation of an acetone power, co‐precipitation as the double cuprous complex with glutathione and removal of the glutathione by means of an ion exchange resin.Improvements over previous processes include use of drum dried yeast plus cold extraction resulting in easy filtration and increase of throughput by a factor of three to five, together with the elimination of the ion exchange step formerly thought necessary to remove zine before the co‐precipitation stage. Under the best conditions yields represent 30% recovery of the co‐enzyme A in the yeast, the product being 90% pure.
An automatic apparatus for extraction of cell suspensions by repeated freezing and thawing
Authors: Billaudelle H. , Brunér P.‐O. 
Published: May 2005

AbstractAn account is given of the construction and operation of a fully automatic apparatus in which the material is kept under agitation in a closed container alternately surrounded by hot and cold alcohol supplied from separate baths. The apparatus has the following applications in microbiology and cell physiology:

Extraction of micro‐organisms and cell tissues by repeated freezing (F) and thawing (T) at variable temperatures and lengths of FT cycle. Extraction can be controlled automatically or manually. As a practical example of the use of the apparatus a description is given of the extraction of living virulent S. typhi bacteria.
Studies of the reactions of living micro‐organisms and tissues under varying physical conditions (e.g. high‐ and low‐temperature resistance experiments, osmotic studies, thermal synchronization of bacterial cultures, etc.).
If required, the normal gas mixture in the residual air space can without difficulty be replaced by other gases or mixtures such as CO2 or N2.
A highly sensitive katharometer and its application to the measurement of ethylene and other gases of biological importance
Authors: Burg Stanley P. , Stolwijk J. A. J. 
Published: May 2005

AbstractThe design and construction of a highly sensitive katharometer is described with special reference to the application of the instrument for the precise determination of traces of ethylene by gas chromatography. Factors influencing katharometer sensitivity, and the relative advantages and disadvantages of katharometers as compared with other types of detectors, are discussed.
Automatic feed device for laboratory‐size glass circulating evaporator
Authors: Barry Guy T. , Pierce Frank 
Published: May 2005

AbstractA simple, rugged and compact automatic feed control attachment for the laboratory‐size glass circulating evaporator has been designed and constructed. Experience has demonstrated that this apparatus operates satisfactorily with a variety of aqueous biological extracts and solutions having resistivity values of 50,000 ohm‐in. or less. The device in adaptable to other evaporators and stills.