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The biological response of human microvascular endothelial cells (HMEC-1) seeded on Si-DLC films and on control surfaces was evaluated in terms of initial cell enhancement, growth, and cytotoxicity. The microstructure of the films was characterised by Raman spectroscopy and X-ray photoelectron spectroscopy. The effect of changes in microstructure, surface energy, surface electronic state, and electronic conduction, on the biological response of the films to endothelial cells was investigated. Endothelial cell adhesion and growth was found to be affected by changes in the microstructure of the films induced by silicon doping and thermal annealing. We observed a significant statistical difference in endothelial cell count between the as-deposited DLC and Si-DLC films using the one sample t-test at a p-value of 0.05. We also found a statistically significant difference between the adhesion of HMEC films on DLC and Si-DLC films at various annealing temperatures using the one-way ANOVA F statistic test at p < 0.05 and the post-hoc Tukey test. One sample t-test at p < 0.05 of MTT-assay results showed the endothelial cells to be viable when seeded on DLC/Si-DLC films. We suspect that the increased adhesion of endothelial cells induced by increasing the amount of silicon in the Si-DLC films is associated with the development of a suitable surface energy due to silicon addition, which neither favored cell denaturing nor preferential water spreading before cellular attachment on the film surface. The presence of an external positively charged dipole on the Si-DLC films confirmed by our Kelvin probe measurements is also expected to enhance the adhesion of endothelial cells that are well known to carry a negative charge. The Si-DLC films investigated hold potential promise as coatings for haemocompatible artificial implants.

A comparative study into two novel and diverse schemes designed to improve immobilization of biomolecules for biosensing purposes is presented. In the first method a silicon rich matrix is created using PECVD. The second method involves creating nano-patterns on the sensor surface to create a large number of surface discontinuities to which the proteins will bind preferentially. The basic theory of SPR is provided to show the importance of the surface sensitive nature of this optical transduction technique. The present work suggests that both may prove both for SPR and other biosensing applications. Of the two schemes proposed, the results for nano-patterning seem to suggest that it is promoting better surface attachment of biomolecules. The results of SPR and AFM studies are presented that have shown that each of these schemes promotes improved binding of various proteins.

Miniaturised point-of-care cardiac marker sensors are being developed, based on impedimetric sensing of cardiac enzyme capture by an antibody layer immobilised on a planar gold electrode sensor. Gold/Ti-on-glass substrates have been used, in a 2 electrode configuration, with antibodies immobilised on the working electrode. Microfluidic structures have been fabricated by a CO2 laser, in 25 mum thick pressure sensitive adhesive (PSA), on a PMMA lid, and the structure bonded on top of the planar sensor. Microfluidic blood/serum delivery has been investigated using a visualisation dye. Some flow problems are observed if the sensor is exposed to air for several days, suggesting that flow channel nanopillars and hermetic encapsulation may be required to guarantee flow properties in commercially produced modules. Work is ongoing to characterise the impedimetric signal changes for myoglobin capture by antimyoglobin, using these sensors. Fifty micron thick PSA, incorporating a robust spacer layer, will be used to give better definition of channel walls.

With the development of critical areas of interdisciplinary research, scientists will lead to an enhanced understanding and control of the key processing stages involved in the design and manufacture of sensor-and electrode-based micro-devices such as micro total analysis systems (muTAS), bio-chips, bio-arrays and DNA sensors. It is anticipated that this fundamental work will lead to tangible technology transfer in the areas of blood analysis, cardiac enzyme detectors, liver and renal function, infectious diseases, gene disorders, etc. These will obviously have major benefits to healthcare delivery. The development of miniaturised, integrated sensor/electrode-based devices are revolutionising both the delivery of health care. In this paper, some of the most exciting research themes in these areas are identified, as well as novel underpinning fabrication technologies and transduction principles, which should make future advances possible.

Diamond-like carbon (DLC) films have been proposed as potential coatings for blood-contacting devices. In this study, tetrahedral amorphous carbon (ta-C) films deposited by filtered cathodic vacuum arc system (FCVA) were compared with commercially deposited polyurethane coatings (PU) and uncoated stainless steel samples. X-ray reflectivity (XRR) measurements were performed to check density and thickness of the ta-C coatings, and contact angles measurements were used to assess surface wettability. J774 macrophages were used to assess the cell responses to the materials. Cell number, metabolic activity, and hydrogen peroxide production were measured by using biochemical assays, and the cell attachment and morphology were determined by using scanning electron microscopy and confocal laser scanning microscopy. Wettability measurements showed that of the materials, the stainless steel was the most hydrophilic, and the ta-C coatings were the most hydrophobic. Although the initial attachment and morphology did not appear to be dependent on the wettability, the cell numbers did increase with increasing wettability. Macrophages on the stainless steel samples were the most active in producing hydrogen peroxide. These data show that ta-C samples performed as well as commercial PU-coated samples in blocking cell reactions to the substrate and may prove to be effective coatings for blood-contacting materials., (Copyright 2004 Wiley Periodicals, Inc.)

Information extracted from whole-nerve electroneurograms, recorded using electrode cuffs, can provide signals to neuroprostheses. However, the amount of information that can be extracted from a single tripole is limited. This communication demonstrates how previously unavailable information about the direction of action potential propagation and velocity can be obtained using a multi-electrode cuff and that the arrangement acts as a velocity-selective filter. Results from in vitro experiments on frog nerves are presented.

Thin film technology takes more and more importance in the development of biomedical devices dedicated to functional neurostimulation. Our research about the design of implant neurostimulating electrode is oriented toward thin film cuff electrodes based on a polyimide substrate covered by a chromium/gold/Pt film. The chromium/gold sputtered film serves as adhesion layer and current collector whereas platinum acts as an electrochemical actuator. The electrode surface has been designed to obey safe stimulation criteria (i.e. chemically inert noble metal, low electrode-electrolyte impedance, high electrochemical reversibility, high corrosion stability). The electrochemical behaviour of such platinum electrodes has been assessed and compared to a foil of platinum. Extensive in vitro characterisations of the both electrode types were carried out using AFM, SEM and electrochemical techniques. The role of enhanced surface roughness enabling high double layer capacitances to be achieved was clearly highlighted. The obtained results are discussed, with particular reference to thin film electrodes stability under in vitro electrical stimulation in NaCl 0.9% (physiological serum). Therefore, these thin film devices showed reversible PtOH formation and decomposition making them potentially attractive for the fabrication of implant stimulation cuff electrodes.

We have investigated the effect of changes in microstructure, surface energy, surface charge condition and electronic conduction on the interaction of human platelets with silicon modified hydrogenated amorphous carbon films (a-C:H:Si or Si-DLC). Results based on Raman spectroscopy, Scanning electron microscopy, X-ray photo-electron spectroscopy, surface energy measurements, electrical resistivity, contact potential difference, and thermal annealing indicates a correlation between some of the measured values and the interaction of the films with human blood platelets. Statistical analysis of platelet aggregation on the films using the Student's t-test indicated differences between platelet aggregation on the modified films compared to the as-deposited film at a p-value of <0.05.

Armillaria mellea sensu stricto (Vahl:Fr.) Kummer has been found infrequently in studies conducted in northeastern North America (2) and it was not found in an earlier survey of northern Ontario (3). In a 1999 survey of Armillaria spp. conducted in central and southern Ontario, A. mellea s. str. was found at four of 110 locations surveyed, two approximately 100 km west and southwest of Ottawa, one 15 km north of Belleville, and one on the Niagara Peninsula in the Balls Falls Conservation Area. At the Ottawa area sites, A. mellea s. str. was found on red oak (Quercus rubra L.) and beech (Fagus grandifolia Ehrh.) stumps. A. ostoyae (Romagn.) Herink and A. gallica Marxmuller & Romagn. were also found on these sites. At the Belleville site, it was found on a dead co-dominant white birch (Betula papyrifera Marsh.), while at the Niagara Peninsula site it was found on a dead, suppressed beech. A. gallica was also found at these latter sites. Sites ranged from moisture regimes fresh to moist, and from sandy to silty soil from both calcareous and non-calcareous parent material. Four isolates were obtained from infected wood and rhizomorphs and identified by the polymerase chain reaction, yielding restriction fragment length polymorphism (RFLP) products of 500 and 183 base pairs. These fragment sizes are similar to findings reported in an earlier study (4). The identification was confirmed by haploid/diploid pairing. The Balls Falls Conservation Area is in close proximity to extensive fruit orchards and the presence of A. mellea is cause for concern, especially in light of its proven pathogenicity to fruit trees (1). This is the first confirmation of A. mellea s. str. in Ontario. References: (1) J. E. Adaskaveg and J. M. Ogawa. Plant Dis. 74:341-352, 1990. (2) J. T. Blodgett and J. J. Worrall. Plant Dis. 76:166-170, 1992. (3) M. T. Dumas. Can. J. For. Res. 18:872-874, 1988. (4) T. C. Harrington and B. D. Wingfield. Mycologia 87:280-288, 1995.

The outcome of total shoulder arthroplasty is largely based on the quality of glenoid component fixation, which, in turn, is related to the amount and quality of bone stock, glenohumeral stability, and rotator cuff function. This article discusses the anatomic and pathologic indications for glenoid replacement, surgical techniques, and results.

Proximal humerus fractures are common injuries and represent approximately 5% of all fractures. These fractures are infrequently associated with neurovascular injuries. Brachial plexus injuries are uncommon, whereas axillary artery injuries are rare. A review of 19 previously reported cases of axillary artery injury after proximal humerus fracture revealed that 84% occurred in patients older than 50 years, 53% were associated with brachial plexus injury, and 21% resulted in upper extremity amputation. This study describes a case of axillary artery injury after proximal humerus fracture and, on the basis of a literature review, offers suggestions for the early diagnosis and effective treatment of this uncommon injury.

This study looks at a group of adolescents who have taken overdoses and examines the type and severity of their problems. It measures hopelessness and depression, and whether these adolescents feel their parents understand them. The study also examines the ways in which these adolescents perceive their overdose as a problem-solving mechanism.The study shows that hopelessness in adolescent self-harm is an important independent variable over and above the level of depression. The adolescents report a wide range of problems with severe and significant problems particularly in the area of family relationships and school.Finally, the paper postulates links between severity of problems, hopelessness and deficits in problem-solving abilities, and suggests areas for potential therapeutic interventions.

A slow cortical wave of high calcium accompanies the elongation of cleavage furrows in medaka fish eggs as well as in Xenopus eggs. We explored the role of such waves by injecting calcium buffers into Xenopus eggs at various times before and during first and second cleavage. Injection earlier than about 15 minutes before first cleavage normally starts delays it for hours. Injection between about 15 minutes and a few minutes before cleavage normally starts allows a (short) furrow to form on time but usually yields an eccentric one. This forms away from the injection side, often as far off-center as the egg's equator, and then regresses. Injection soon after it starts quickly arrests elongation of the furrow and eventually induces its regression; while injection a bit later likewise soon arrests elongation but allows delocalized furrow deepening to continue. The dependence of these inhibitory actions upon the dissociation constants and final cytosolic concentrations of the injected buffers indicates that they act as shuttle buffers to suppress needed zones of high calcium in the micromolar range. We conclude that the high calcium that is found within these furrows is needed to induce them, to extend them and even to maintain them. Moreover, while short, eccentric furrows often form as far off center as the equator, they somehow always form along a meridian through the animal pole. This seems difficult to explain by the orthodox, diastral model. Rather, it suggests that the cleavage furrows in Xenopus--and perhaps in animal cells quite generally--are directly induced by a diastema or telophase disc rather than by the asters.

This study examined neuroanatomical differences between male schizophrenic patients with a family history of psychosis (n = 16) and those without such a history (n = 15). Intracranial area, cerebral area, ventricular size, and cortical atrophy were assessed using magnetic resonance imaging (MRI). Third ventricular enlargement was more prevalent in patients than controls (n = 15). Familial and nonfamilial patients differed significantly. Reduced cranial and cerebral areas without ventricular enlargement characterized familial patients, whereas nonfamilial patients showed marked lateral ventricular enlargement without a reduction in cranial/cerebral size.

Near the end of the data-collection phase of a case-control interview study of environmental factors and childhood brain tumors, an unusual space-time cluster was revealed. Not only had six genetically unrelated children been diagnosed with a primary intracranial tumor in a recent 2.4 year period in a rural county in Ohio, but each child had one parent employed by the same company (two mothers, four fathers). This represents an observed/expected ratio greater than 70 (p much less than 0.001). All tumors were microscopically confirmed, and all case parents worked at the facility in question for at least 1 year prior to conception, during the index pregnancy, and for at least 6 months after birth. The place of parental employment was an electronics firm (Standard Industrial Classification [SIC] group number 367, electronic components and accessories), where more than 100 chemical compounds are used by the company in a manufacturing process. Results of the cluster investigation are described, including a description of the case series. This cancer cluster is unique in that the index case series is composed of the offspring of workers, not the workers themselves.

Glyoxal and methylglyoxal interact with biogenic amines and form biologically active free radicals. Electron spin resonance absorption of the radical at room temperature is characterized by a signal at g equals 2.004 with peak-to-peak width of 29 G. An optical absorption at 400 nm with molar absorptivity of 23,000 accompanies the formation of the radical. The dry powdered preparation of the same reaction, which is considered to be the seconardy product, gives an electron spin resonance signal much narrower and 1/200 in intensity compared with the one in solution. Similarly the 400 nm absorption intensity is 1/8 that of the primary product. Possible biological significance of the primary and the secondary product, in relation to muscular dystrophy and photophosphorylation, is discussed.

A case is described in which a diagnosis of paranoid schizophrenia was made using the criteria of Schneiderian first-rank symptoms. The patient showed the Capgras syndrome, with delusional misidentification of her son and other people in her environment, and also Ekbom's syndrome, with the delusion that she was infested with parasitic worms which migrated between various parts of her body. In this case, the two syndromes are descriptions of a specific delusional content, and occur as part of the psychopathology within a schizophrenic disorder, rather than as distinct disease entities.

The rate of scavenging by Ehrlich ascites cells of anionic ascorbyl and 2,6-dimethoxy-p-semiquinone free radicals has been investigated by electron spin resonance spectroscopy both for viable cells and for subcellular fractions obtained by differential centrifugation. The scavenging activity is concluded to be associated with an NAD(P)H enzyme containing an active sulfhydryl group. Attempts to identify the enzyme with the reported properties of either semi-dehydro-ascorbate reductase or DT-diaphorase have not been successful. The overall free-radical scavenging activity for viable cells is dextrose dependent and is controlled by the coulombic barrier associated with the cell-surface charge. The cytotoxicity of the mixture of ascorbic acid with 2,6-dimethoxy-p-benzoquinone is concluded to result from a loss of NAD(P)H reducing power in the cells.

The rate of quenching by Ehrlich ascites cells of anionic 2,6-dimethoxy-p-semiquinone and ascorbyl free radicals is investigated as a function of cell concentration, the blocking of cell-surface sulfhydryl groups by N-ethylmaleimide, and the reduction of cell-surface charge by neuraminidase. The rate of quenching is found to be proportional to cell viability and to the number of free cell-surface sulfhydryl groups. The enzymatic action of neuraminidase results in an increase of the free radical quenching rate, indicating that this rate can be used as a probe of cell-surface charge. Measurements as a function of the ionic strength of the suspending electrolyte gave a value of -1.22 microC X cm-2 for the charge density at the ascites cell surface. This is equivalent to a surface membrane potential of -14 mV for a 150 mM NaCl electrolyte and is a value in good agreement with published electrophoresis data.

Spectroscopic measurements are reported for the effects of pH, time, solvent, and chemical modification of arginine and lysine side chains on the reaction of proteins with methylglyoxal. The reaction responsible for the appearance of a brown coloration and increased submolecular electronic activity in the proteins involves the epsilon-amino groups of the lysine residues. It is concluded that the primary step in the reaction involves the formation of a Schiff base linkage between the lysine side chain and methylglyoxal. These findings reaffirm the concept that, by the formation of Schiff bases, aldehydes can act as electron acceptors in charge transfer interactions with proteins.

Standard midpoint potentials have been determined for p-benzoquinone, methoxy-p-benzoquinone and 2,3-, 2,5-, and 2,6-dimethoxy-p-benzoquinones in aqueous solution. ESR studies have been made of the ascorbate and semiquinone radicals produced when these quinones interact with sodium ascorbate. Direct correlations are found between the electrochemical potentials, generated semiquinone lifetimes, and cytotoxic action in Ehrlich ascites-bearing mice.

We have investigated the effects of recombinant interleukin-1 beta (rIL-1 beta) on phospholipase A2 activity (PLA2), PLA2 messenger RNA levels, and eicosanoid production in rabbit chondrocytes. Phospholipase A2 activity increased 5 fold with exposure to 1.6 x 10(-11) M rIL-1 beta for 20 hours. An mRNA specific for an extracellular PLA2 was detected by RNA blot hybridization after treatment of the cells with rIL-1 beta. Hydroxylated derivatives of arachidonic acid, including prostaglandins, leukotriene B4, 5-hydroxyeicosa 6E, 8Z, 11Z, 14Z-tetraenoic acid, 12-hydroxyeicosa 5Z, 8Z, 10E, 14Z-tetraenoic acid and 15-hydroxyeicosa 5Z, 8Z, 11Z, 13E-tetraenoic acid increased in cells after rIL-1 beta treatment.

The Collaborative Ocular Melanoma Study (COMS) is an international, multicenter-controlled study. The organization includes an Executive Committee, Steering Committee, 6 Central Units, 32 Clinical Centers, and a Data and Safety Monitoring Committee. Scientifically, the COMS consists of (1) a randomized trial of patients with medium choroidal melanoma treated with enucleation versus iodine-125 plaque irradiation, (2) a randomized trial of patients with large choroidal melanoma treated with enucleation versus preenucleation external beam irradiation and enucleation, and (3) a prospective observational study of patients with small choroidal melanoma to determine whether a randomized trial of treatment is appropriate. In design and conduct of the COMS, special consideration is given to biostatistics and sample size considerations, iodine-125 plaque irradiation of choroidal melanoma, and coordinated ocular melanoma research. Recruitment is in progress. However, the pool of eligible patients is limited and the COMS needs the continued support and cooperation of ophthalmologists throughout the United States and Canada.

History of perinatal complications (PCs) and first degree family history (FH) of psychiatric illness were examined in groups of schizophrenic/schizoaffective (n = 21) and bipolar (n = 10) patients. PCs were significantly more frequent in the schizophrenic and schizoaffective patients than in bipolar patients. An inverse relationship was found between PCs and FH status, with FH-positive patients having significantly fewer PCs than the FH-negative group. This relationship persisted when the bipolar patients were excluded. Findings emphasize the etiological importance of genetics and perinatal events in the psychoses, and support the validity of a familial/sporadic distinction.

Many problems are left open in this article. Its publication may be excused by the suffering cancer causes, which urges the researcher to publish as soon as he thinks he may have found a new trail, which also may be taken by others. What emerges clearly is that SH groups, with their specific reactivities, offer a hopeful target in the search for cancerostatic substances, among which the natural repressor of cell division may hold out the most promise. The glyoxal derivatives also have antiviral properties (7, 16) and may be in the center of a hitherto unknown system of equilibria which deserves a thorough study. The low molecular weight of the glyoxal derivative reported justifies the hope of an early clarification of its structure, as well as its synthesis (17).

Human urine contains "retine." Its partial isolation is described.

Two substances, one promoting growth (promine) of ascites tumors in mice and the other inhibiting it (retine) have both been found in several tissues, namely, thymus, aorta, muscle, and tendon. In spite of similar solubilities in the solvents used for their extraction, the substances could be roughly separated. The value of the ratio between these substances in the same tissue may be significant.