SEARCH · Search PubMed

Results for “prototype”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 793 records · Page 44Linked to original sources

PubMed2002

Evaluation of a prototype multi-posture office chair.

Office chairs have often been designed to promote a single 'correct' rather rigid and upright posture, yet it is acknowledged that allowing changes in posture is good ergonomics practice. The present study investigated office worker's preferences for a standard shaped typist's chair (ST) and a prototype multi-posture (PMP) office chair designed to allow its users a variety of sitting positions. Forty-two (22 male and 20 female) telesales personnel (12), clerical staff (12) and researchers (18) used ST or PMP in their workplace for the first week of a 2-week study (with an even number in each work area). The PMP chair was introduced to participants with a brief lecture on how to use it and with an information booklet. Following this, each participant completed a chair comfort questionnaire. In the second week, participants swapped chairs and again completed the chair comfort questionnaire. At the end of the second week participants were also asked to complete a separate questionnaire about the usability of the information booklet that accompanied the PMP chair. Statistically significant differences in subject's rating of the two chairs were observed in 7 out of 19 questions. On a 100 mm scale, the ST chair was rated as having a greater mean overall acceptability, desirability and suitability for body build than the PMP chair. Participants also claimed to achieve better posture in the ST chair, that they tipped forward less and were more satisfied with its width. Although the participants generally preferred the ST chair, the PMP chair received more favourable ratings among the researchers who were quite mobile in their work, and in whom there was a trend for less neck, shoulder and upper back discomfort. More participants reported an overall preference for the PMP chair. The findings suggest that a more aesthetically acceptable PMP chair should be developed, peoples' reasons for preferring a more traditionally designed chair should be explored, and that the effect of postural stability education on personal preconceptions should be examined to obtain an optimal combination of healthy sitting habits, comfort and aesthetic qualities in an office chair.

Adult↗

PubMed2005

Rapid serological diagnosis of melioidosis: an evaluation of a prototype immunochromatographic test.

AIMS: To evaluate the Panbio melioidosis prototype (ICT) IgG and IgM test kits in detecting antibodies to Burkholderia pseudomallei from an endemic region of Australia. This would be of particular importance in high prevalence, low resource regions. METHODS: Seventy-five culture-confirmed sera for melioidosis and 158 negative control sera from subjects in North Queensland were tested. All sera samples were also tested with an in-house indirect haemagglutination assay (IHA). Seventy-three of the positive sera were further tested using an in-house EIA IgG and IgM assay. RESULTS: The Panbio IgG kits had a sensitivity of 50.6% (95%CL 38.9-62.4) and a specificity of 97.4% (95%CL 93.7-99.3). The Panbio IgM kits had a sensitivity and specificity, respectively, of 72.0% (95%CL 60.4-81.8) and 71.5% (95%CL 63.8-78.4). CONCLUSIONS: The ICT kits were found to be rapid and easier to use than current serological methods. In particular, the IgG ICT kit would have a potential role in determining existing disease in low resource regions.

Burkholderia pseudomallei↗

PubMedDate not supplied

Skeletal myopathy in transgenic mice carrying human prototype c-Ha-ras gene.

Skeletal myopathy was found in almost all-transgenic mice carrying the human prototype c-Ha-ras gene (rasH2 mouse). Microscopically, variation of the muscle fiber size, centrally placed nuclei, regenerating fibers, and interstitial fibrosis were evident; hyalinization and necrosis were sometimes observed in the skeletal muscle (femoralis and pectoralis) of the rasH2 mice. Inflammatory changes in the skeletal muscle or abnormality of adjacent peripheral nerve were not observed. The features were essentially similar to those of muscular dystrophy. Although the severity was relatively mild compared to 34-week-old rasH2 mice, the skeletal myopathy was also observed in younger male (10 weeks of age) rasH2 mice. In nontransgenic littermates, skeletal myopathy was not observed. The mRNA of human c-Ha-ras product was detected in femoral muscle from the rasH2 mice by RT-PCR. In conclusion, these data suggest that skeletal myopathy is occurring in almost all rasH2 mice. Integration of c-Ha-ras gene is thought to be crucial to pathogenesis of skeletal myopathy in the rasH2 mice. Further characterization of the muscular lesion and its pathogenesis are needed to explore the possibility of rasH2 mouse becoming a new model for muscular dystrophy.

Animals↗

PubMedDate not supplied

Mutation and overexpression of the transgene in ethylnitrosourea-induced tumors in mice carrying a human prototype c-Ha-ras gene.

To investigate mechanisms underlying accelerated carcinogenesis in mice carrying a human prototype c-Ha-ras gene (rasH2 mouse), mutations and the expression profile of the transgene were evaluated in 14 tumors induced by a single injection of ethylnitrosourea (ENU), with or without additional beta-estradiol 3-benzoate (EB) treatment. Although no codon 12 mutations were detected, changes in codon 61 were evident in all lung adenocarcinomas, skin squamous cell carcinomas and forestomach squamous cell carcinomas examined. The mRNA levels of the transgene in these lesions were also elevated 1.71- to 4.77-fold, 3.04- to 5.18-fold, and 3.00- to 5.67-fold, respectively, in comparison with those in the normal livers of rasH2 mice. The results obtained in this study suggest that mutations in codon 61 and amplification of the transgene play key roles in the carcinogenesis induced by ENU in rasH2 mice.

Adenocarcinoma↗

PubMedDate not supplied

PROTOTYPES: an urban model program of treatment and recovery services for dually diagnosed perinatal program participants.

PROTOTYPES, a women's treatment program located in Los Angeles, is described in terms of its services for pregnant and parenting women with coexisting substance abuse and mental health disorders. The philosophy of treatment, goals and objectives, treatment planning process, and treatment content are discussed. Management of the milieu, relational model considerations and staff self-care issues are presented in addition to future directions in treatment and research on women with coexisting disorders.

Diagnosis, Dual (Psychiatry)↗

PubMedDate not supplied

A review of rapid prototyping (RP) techniques in the medical and biomedical sector.

The evolution of rapid prototyping (RP) technology is briefly discussed, and the application of RP technologies to the medical sector is reviewed. Although the use of RP technology has been slow arriving in the medical arena, the potential of the technique is seen to be widespread. Various uses of the technology within surgical planning, prosthesis development and bioengineering are discussed. Some possible drawbacks are noted in some applications, owing to the poor resolution of CT slice data in comparison with that available on RP machines, but overall, the methods are seen to be beneficial in all areas, with one early report suggesting large improvements in measurement and diagnostic accuracy as a result of using RP models.

Biomedical Engineering↗

PubMedDate not supplied

Reverse engineering techniques applied to a human skull, for CAD 3D reconstruction and physical replication by rapid prototyping.

The production of a copy of an existing object of complex shape is one of the typical applications of the integration between two modern computer-based technologies, reverse engineering (RE) and rapid prototyping (RP). The method is extremely versatile and can be used in various applicative domains (e.g. replacement of anatomical parts with artificial prostheses, replication of skeletal remains). Two different acquisition techniques of images of a skull, by laser and by CT scan, were compared to ascertain which enabled more accurate reproduction of the original specimen. The skull was chosen due to it being the body part most often used in medico-legal investigations (for personal identification, skull-photo superimposition techniques, forensic art, etc). Comparison between the copy and the original yielded satisfactory results for both techniques. However, CT scanning demonstrated some advantages over the laser technique, as it provided a cleaner point cloud, enabling shorter pre-reproduction processing times, as well as data on the internal parts, which resulted in the reproduction of a more faithful copy.

Biomedical Engineering↗

PubMedDate not supplied

Medical rapid prototyping and 3D CT in the manufacture of custom made cranial titanium plates.

This report describes a new method of custom making cranial titanium plates for the repair of skull defects. We have combined 3D CT imaging and surface modelling with rapid prototyping (RP) technology to produce physical models of our patients' skulls from which custom titanium plates were made. We have expanded the use of image processing tools applied to the CT image data to fabricate a representation of the skull defect. Medical RP models are relatively expensive and particular attention has been paid to developing image processing methods to reduce costs. Our technique used the patient as their own model and generated data from the contralateral side of the head where appropriate. We present the results of 10 patients who have had a custom made cranial titanium plate fitted and discuss the models for these cases. The benefits of our custom made titanium plates are reduced patient attendances to hospital and a more accurate titanium plate which has improved fitting and cosmesis.

Bone Plates↗

PubMed1991

The binding of prototype lexitropsins to the minor groove of DNA: quantum chemical studies.

Ab initio calculations (Hartree-Fock) using the 6-31 G basis set have been performed on two prototype lexitropsins or information-reading molecules. The latter are DNA minor groove binding agents related to the A.T recognizing netropsin in which each of the two N-methylpyrrole moieties is replaced in turn by 1-methylimidazole and which thereby confers the property of recognizing G.C sites.Ab initio treatment was possible by examining composities of separate non-conjugated segments of the molecules. Geometry optimized conformations, energies and distribution of electrostatic charges within the molecules were derived. The ab initio derived parameters of the geometry optimized conformations of these lexitropsins were used to interpret their interaction with different sequences within the minor groove of B-DNA.

Base Sequence↗

PubMedDate not supplied

Comparative kinetic analysis of AzgA and Fcy21p, prototypes of the two major fungal hypoxanthine-adenine-guanine transporter families.

In fungi, uptake of salvageable purines is carried out by members of two evolutionarily distinct protein families, the Purine-Related Transporters (PRT/NCS1) and the AzgA-like Transporters. We carried out a comparative kinetic analysis of two prototypes of these transporter families. The first was Fcy21p, a herein characterized protein of Candida albicans, and the second was AzgA, a transporter of Aspergillus nidulans. Our results showed that: (i) AzgA and Fcy21p are equally efficient high-affinity, high-capacity, purine transporters, (ii) Fcy21p, but not AzgA, is an efficient cytosine and 5-fluorocytosine transporter, interacting with =O2 and C4-NH2 of the pyrimidine ring, (iii) the major interactions of AzgA and Fcy21p with the purine ring are similar, but not identical, involving in all cases positions 6 and 7, and for some substrates, positions 1 and 9 as well, and (iv) in AzgA, bulky groups at position N3 have a detrimental steric effect on substrate binding, while similar substitutions at C2 or N9 are fully or partially tolerated. In contrast, in Fcy21p, C2 and N9 bulky substitutions abolish substrate binding, while similar substitutions in N3 are fully tolerated. These results suggest that all fungal purine transporters might have evolved from a single ancestral protein, and show that fungal transporters use different substrate interactions compared to the analogous protozoan or mammalian proteins. Finally, results are also discussed in respect of the possibility of using fungal purine transporters as specific gateways for the development of targeted antifungal pharmacological therapies.

Adenine↗

PubMed2001

Incineration of paper sludge in a prototype vortexing fluidized bed combustor.

All experiments were carried out in a prototype vortexing fluidized bed combustor (VFBC). The dimension of the combustion chamber is 0.7 x 1.4 x 2 m, and the freeboard section is 1 m i.d. and 4 m in height. Paper sludge was used as the feeding material. Two types of coal particles were employed as the supplementary fuel. In order to understand the characteristics of the VFBC system for paper sludge incineration, the effect of various operating parameters, such as the primary airflow, excess air ratio, and secondary airflow rates, on temperature distribution, ash elutriation, combustion efficiency, and pollutant emissions were investigated.

Air Pollution↗

PubMed2003

Mini-fingerprints for virtual screening: design principles and generation of novel prototypes based on information theory.

Binary fingerprint representations of molecular structure and properties are convenient computational tools for similarity searching in compound databases and virtual screening (VS). We are investigating the design of relatively simple fingerprints for the identification of molecules having similar biological activity and recognition of remote similarity relationships. Since our designs are considerably shorter than other fingerprints used in VS, we have previously termed them "mini-fingerprints" (MFPs). A key aspect of the design strategy is the identification of suitable molecular descriptors. Whereas our initial fingerprint designs have relied on descriptor combinations that performed well in compound classification according to biological activity, second generation MFPs encode combinations of descriptors with high information content in large compound databases and high frequency of occurrence in drug-like molecules. Thus, the design of these new fingerprints does not depend on the analysis of specific classes of bioactive compounds, but rather on descriptor information content in large compound databases. Systematic evaluation of fingerprint performance in VS test calculations demonstrates that these new prototypes perform better than previously generated MFPs. The analysis described herein provides an example for the development of search tools for VS.

Environmental Pollutants↗

PubMed2005

Predictors of young adults' representations of and behavior in their current romantic relationship: prospective tests of the prototype hypothesis.

Although attachment theory suggests that childhood experiences with caregivers serve as a prototype for adult love relationships, few explicit tests of this hypothesis exist in the literature. Drawing on data from a longitudinal cohort followed from birth to young adulthood, this paper examined correlates and antecedents of young adults' representations of and behavior in their current romantic relationship. Young adults who experienced a secure relationship with their primary caregiver in infancy as assessed in the Strange Situation were more likely to (a) produce coherent discourse regarding their current romantic partnership in the context of the Current Relationship Interview (CRI) and (b) have a higher quality romantic relationship as observed in standard conflict and collaboration tasks. Infant security accounted for variation in CRI security above and beyond the observed quality of participants' current romantic relationship. In contrast, the association between infant and romantic security was partially mediated by individuals' self-reports about their romantic experiences, suggesting that one plausible mechanism by which early experiences with caregivers shape young adults' representations of their attachments with romantic partners is through adults' expectations for and perceptions of love relationships.

Adult↗

PubMed2004

A prototype vessel compressor helps efficient laser treatment of small leg veins.

The eradication of small leg veins with lasers continue to present problems. Visible light lasers (488 nm approximately 595 nm) are well absorbed in haemoglobin but melanin is also a target, necessitating aggressive skin cooling to prevent damage to the epidermis and adding to the expense of these laser systems. A new generation of much less expensive semiconductor-based lasers operating in the near infrared offers a different approach, with protein as the main target rather than pigment. For visible light lasers, compression of the target vessels is a contraindication, since the target pigment is removed. For near IR diode lasers, however, compression of the vessels is a benefit, as the cooling effect of the blood flow is removed and the highly proteinous vessel walls are coapted which encourages efficient coagulative vessel closure. The prototype of a simple vessel compressor is presented, which first compresses vessels and coapts the walls, and then presents the coapted vessels as a target for a laser of an appropriate wavelength.

Humans↗

PubMed2002

Clonidine displacement from type 1 imidazoline receptor by p-aminobenzamidine, the prototype of trypsin-like serine protease inhibitors.

p-Aminobenzamidine inhibits competitively the catalytic activity of enzymes that recognize preferentially the L-arginyl side chain and related structures. Notably, p-aminobenzamidine is considered as the prototype of trypsin-like serine protease inhibitors. Furthermore, p-aminobenzamidine inhibits the catalytic activity of nitric oxide synthase type I and type II as well as copper amine oxidase. Taking into account the structural similarity between p-aminobenzamidine, agmatine (the putative endogenous ligand of the membrane type 1 imidazoline receptor (I1-R)), and N-amidino-2-hydroxypyrrolidine (the product of agmatine oxidation by copper amine oxidase), the [3H]clonidine displacement from I1-R in rat heart membranes by p-aminobenzamidine was investigated. p-Aminobenzamidine is as effective as agmatine and N-amidino-2-hydroxypyrrolidine and more effective than the antihypertensive drug clonidine to displace [3H]clonidine from I1-R. Therefore, trypsin-like serine protease inhibitors structurally related to p-aminobenzamidine should be administrated under careful control.

Adrenergic alpha-Agonists↗

PubMed1979

Assessment of hazardous air pollutants from disposal of munitions in a prototype fluidized bed incinerator.

As part of the control technology development for the disposal of waste munitions, an assessment of potential emissions of hazardous air pollutants from a prototype fluidized bed incinerator was conducted. Assessment program elements included identification of potentially toxic emissions through material input analysis and computer simulation modeling of the combustion cycle; development of emission limitations criteria for substances having no present air pollution emission standards; evaluation and development of analytical procedures; and design of a sampling system to condition an emission stream characterized by high temperature and humidity resulting from burning water slurries of explosive materials. Emphasis is placed on the potential emission of nickel and its compounds, particulate and vapor emissions of cyanides, nitrogen oxides, and TNT and RDX energetic residuals.

Air Pollutants↗

PubMed2005

Human T lymphotropic virus types I and II western blot seroindeterminate status and its association with exposure to prototype HTLV-I.

Human T lymphotropic virus types I and II (HTLV-I/II) Western blot (WB) seroindeterminate status, which is defined as an incomplete banding pattern of HTLV protein Gag (p19 or p24) or Env (GD21 or rgp46), is commonly observed. To investigate the significance of this finding, we examined HTLV-I/II serostatus and HTLV-I proviral load in 2 groups of individuals with WB seroindeterminate status. Low proviral loads were detected in 42% of patients with neurologic symptoms and 44% of voluntary blood donors. These data suggest that a subset of WB seroindeterminate individuals may be infected with prototype HTLV-I. To confirm this hypothesis, we evaluated HTLV-I/II serostatus and proviral load in prospectively collected specimens from 66 WB seronegative patients who had received HTLV-I-infected blood products by transfusion. Eight individuals developed WB seroindeterminate profiles after the transfusion. In addition, using a human leukocyte antigen type A*201-restricted HTLV-I Tax11-19 tetramer, we detected virus-specific CD8(+) T cells in peripheral blood mononuclear cells from WB seroindeterminate patients. These CD8(+) T cells were effective at targeting HTLV-I-infected cells. Collectively, the results suggest that HTLV-I/II WB seroindeterminate status may reflect a history of HTLV-I exposure. Our findings warrant further investigation of the possible clinical outcomes associated with WB seroindeterminate status.

Blood Donors↗

PubMed1985

A prototype digital ionographic imaging system.

A prototype digital ionographic imaging system is described. The process involves direct electrical reading of a latent electrostatic image which has been produced by an ionographic technique. The main design features of the system are outlined and their effect on its imaging performance highlighted. A preliminary assessment of the performance of the system in terms of resolution, noise, contrast and sensitivity is presented and compared with that of a conventional screen-film combination.

Analog-Digital Conversion↗