Search PubMed⌕ Search

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.

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

At least 883 records · Page 49Linked to original sources

Production and characterization of monoclonal strain-specific antibodies against prototype strains of Rickettsia tsutsugamushi.

We have developed 18 hybridoma cell lines which secrete murine monoclonal strain-specific antibodies to prototype strains of Rickettsia tsutsugamushi: nine anti-Gilliam, four anti-Karp and five anti-Kato antibodies. All the monoclonal antibodies reacted only with their homologous strains in direct and indirect immunofluorescence (IF), or indirect immunoperoxidase (IP) test. By IF and IP tests with the monoclonal antibodies, 22 strains of R. tsutsugamushi, which were newly isolated from mites, field rodents and patients with Tsutsugamushi disease (scrub typhus) in Japan, were all clearly identified as either Gilliam or Karp type. Analysis by polyacrylamide gel electrophoresis and immunoblotting techniques revealed that the monoclonal antibodies recognized primarily the polypeptides of an apparent molecular weight of 54 to 56 kilodaltons of the homologous rickettsial surface. The monoclonal antibodies produced in the present study should enhance the serotyping and further analytical investigation of the rickettsial antigens since they recognize the strain- or type-specific polypeptides and do not show any cross-reaction among strains.

Animals↗

Agent-specific filling devices. An evaluation of two prototypes.

Two prototype agent-specific devices have been tested and neither in its present form is ideal. Filling of vaporisers may be delegated to inexperienced persons but the devices tested do not ensure that vaporisers can only be filled with the correct agent. Significant atmospheric pollution with the volatile anaesthetic agent may occur at the time of filling. At present, the devices are limited to three agents, enflurane, halothane and methoxyflurane.

Anesthesia, Inhalation↗

A combined oxygen concentrator and compressed air unit. Assessment of a prototype and discussion of its potential applications.

A prototype combined oxygen concentrator and air compressor is described. Laboratory assessment demonstrated satisfactory oxygen concentrations, flows, pressures and reliability. Its various modes of use in clinical practice are described. It is likely to be a valuable method to provide oxygen for anaesthesia both in remote areas and where nitrous oxide-free anaesthesia is required, as well as a reliable alternative to commercially produced oxygen for therapeutic purposes.

Anesthesiology↗

Infundibular keratosis--a prototype of benign infundibular tumours.

Three cases of a benign follicular tumour of infundibular origin are reported. The neoplasms were solitary, verrucous, slowly-growing papules or nodules on the face, which were diagnosed clinically as verruca vulgaris or seborrhoeic keratoses. Histologically, several epithelial lobules were seen, mainly above the level of the surface of the surrounding skin, with characteristic funnel-shaped invaginations. The tumours occasionally contained vellus hairs or were connected with sebaceous glands and/or hair follicles at their bases, indicating their follicular origin. The tumour masses consisted of peripherally arranged basaloid and inner squamoid cells. The latter cells contained more glycogen and appeared paler with haematoxylin and eosin (H&E) stains than the normal inter-follicular squamous cells. Neither clear cells nor squamous eddies were observed. Palisading of the basaloid cells was not a prominent feature. The name 'infundibular keratosis' is proposed for such tumours, which probably represent the prototype of infundibular tumours of the hair follicle.

Aged↗

Development of an expert system for bacterial identification: study of a prototype for identifying beta-galactosidase positive enterobacteria.

A prototype of an expert system for the identification of beta-galactosidase positive Enterobacteriaceae has been developed, for use with the API 20 EC kit. The system is implemented in Prolog on an IBM PC AT with 640 K of central memory and 20 megabytes of secondary memory. Its objectives are to highlight errors that can occur when the kit is in use. It can indicate the presence of new groups or species and give advice or suggest additional tests for the differentiation of the new species from those included in the kit.

Enterobacteriaceae↗

The amino acid sequence of glutathione transferase from Proteus mirabilis, a prototype of a new class of enzymes.

The complete amino acid sequence of glutathione transferase from Proteus mirabilis was determined. The sequence was reconstructed by analysis of peptides obtained after cleavage by trypsin, Glu-C and Asp-N endoproteinases. The enzyme subunit is composed of 203 amino acid residues corresponding to a molecular mass of 22856 Da. Comparison of this sequence with other known primary structures of the corresponding enzyme from different sources shows a low level of identity (17-26%) with only seven conserved residues in all the sequences considered. This novel glutathione transferase could represent the prototype of a new class, possibly including other bacterial enzymes.

Amino Acid Sequence↗

Novel effects of the prototype translocating Escherichia coli, strain C25 on intestinal epithelial structure and barrier function.

Intestinal bacteria play an etiologic role in triggering and perpetuating chronic inflammatory bowel disorders. However, the precise mechanisms whereby the gut microflora influences intestinal cell function remain undefined. Therefore, the effects of the non-pathogenic prototype translocating Escherichia coli, strain C25 on the barrier properties of human T84 and Madine-Darby canine kidney type 1 epithelial cells were examined. T-84 cells were also infected with commensal E. coil, strains F18 and HB101, and enterohaemorrhagic E. coli, serotype O157:H7. Strains F18 and HB101 had no effect on transepithelial electrical resistance (TER) of T84 monolayers. By contrast, epithelial cells infected with strain C25 displayed a time-dependent decrease in TER, preceded by an altered distribution of the cytoskeletal protein alpha-actinin, comparable to infection with E. coli O157:H7. E. coli C25 infection also led to activation of nuclear factor kappaB (NF-kappaB), interleukin-8 secretion and alterations in localization of claudin-1, but not zona occludens-1 or claudin-4, in T84 cells. There were adherent C25 bacteria on the intact apical surface of infected T84 cells, while mitochondria appeared swollen and vacuolated. These novel findings demonstrate the ability of a translocating commensal bacterium to adhere to and modulate intestinal epithelial barrier function and to induce morphological changes in a manner distinct from the known enteric pathogen, E. coli O157:H7.

Animals↗

Does hematocrit affect in vitro hemolysis test results? Preliminary study with Baylor/NASA prototype axial flow pump.

The effect of hematocrit (Ht) on in vitro hemolysis test results (i.e., index of hemolysis) was evaluated using a Baylor/NASA prototype axial flow pump. Red blood cell suspensions of six different Ht (5, 10, 15, 20, 30, 40%; n = 30) were prepared and used for this evaluation. The pump was operated for 60 min under 5 L/min flow conditions, and blood samples were taken every 10 min to measure plasma free hemoglobin levels. The normalized index of hemolysis (NIH) was calculated using the regression line slope between time and plasma free hemoglobin level, and relationships between NIH and Ht or hemoglobin (Hb) were checked. NIH and Ht had a statistically significant (p < 0.0001) correlation with a coefficient of fit of 0.976, and NIH and Hb had a statistically significant (p < 0.0001) correlation with a coefficient of fit of 0.976. To reduce the effect of Ht, NIH/Ht was proposed and compared with a modified index of hemolysis (MIH), which was normalized by the Hb level of blood. NIH/Ht and MIH had a poor correlation with Ht (coefficient of fit, 0.608) and Hb (coefficient of fit, 0.577), respectively. When blood that has a wide range of Ht or Hb values is used for in vitro hemolysis tests, NIH/Ht is suggested for use as an index of hemolysis to evaluate the hemolysis characteristics of rotary blood pumps because MIH has no dimension and it requires Hb values. In contrast, NIH/Ht has a dimension of g/100 L, which is quite understandable, and it does not require measurement of Hb levels of blood; it is therefore cost-effective.

Animals↗

Photoelectric dye-coupled polyethylene film as a prototype of retinal prostheses.

Photoelectric dyes, which absorb light and convert photon energy to electric potentials, have been previously shown to stimulate retinal neurons in culture. In this study, a photoelectric dye was coupled to a polyethylene film surface and tested in vitro using retinal tissues from chick embryos at the 12-day embryonic stage, at which time outer segments of retinal photoreceptor cells have not yet developed. Carboxyl moieties were introduced to a polyethylene film surface by fuming nitric acid, and then a photoelectric dye, 2-[2-[4-(dibutylamino)phenyl]ethenyl]-3-carboxymethylbenzothiazolium bromide, was coupled to the film through amide linkage. Intracellular calcium elevation was observed with Fluo-4 in retinal tissues placed on the dye-coupled polyethylene film, in contrast to retinal tissues which had no contact with the film. The response was inhibited by calcicludine, a voltage-gated calcium channel blocker, and also by extracellular calcium depletion. The photoelectric dye, coupled to the polyethylene film surface, absorbed light under a dissecting microscope and stimulated neurons in retinal tissues, showing that the dye-coupled film could be used as a prototype of retinal prostheses.

Aniline Compounds↗

Comparative anticonvulsant activity of 4-chlorobenzenesulfonamide and prototype antiepileptic drugs in rodents.

The anticonvulsant and toxic properties of 4-chlorobenzenesulfonamide (ADD 55051) were compared with phenytoin (PHT), phenobarbital (PB), ethosuximide (ESM), and valproate (VPA). These compounds were evaluated in mice and rats using well-standardized anti-convulsant test procedures. The results indicate that ADD 55051 is a very effective anticonvulsant in the maximal electroshock seizure (MES) model in mice after either intraperitoneal (i.p.) or oral administration and in rats after oral administration. In mice treated i.p. or orally, ADD 55051 was also effective in preventing seizures induced by pentylenetetrazol (PTZ). The toxicity of ADD 55051 after oral administration was quite low, yielding high TD50 values in both mice and rats and producing a very high protective index (PI = TD50/ED50) in both species as compared with the prototype antiepileptic drugs (AEDs).

Animals↗

Multiplane Transthoracic Echocardiography: Image Orientation, Anatomic Correlation, and Clinical Experience with a Prototype Phased Array Multiplane Surface Probe.

Multiplane transthoracic echocardiography provides numerous sequential images by rotation of the transducer imaging array through 180 degrees with the surface probe at a fixed site. We explored the potential of this new technique with a 3.7/5-MHz prototype multiplane transthoracic probe. Echoanatomic correlations were first examined in ten explanted hearts. The transducer was then applied in 30 normal humans at transthoracic acoustic windows to determine the imaging planes available. Use of this probe in 76 patients with various cardiac disorders indicated that this probe eases the procedure of transthoracic echocardiographic examination, provides incremental information for improved delineation and understanding of cardiac pathology, and yields many novel insights to echocardiographic interpretation. Multiplane transthoracic echocardiography appears to expand the versatility of transthoracic two-dimensional echocardiography.

Journal Article↗

Genotypic and phenotypic characterization of two Swedish isolates and two prototypic strains of Coxiella burnetii.

Two Swedish isolates of Coxiella burnetii and the two prototype strains of the species, Nine Mile and Priscilla, were characterized with regard to their multiplication and cytopathic effect on BGM cells and by PCR-based amplification of repetitive element DNA and the C. burnetii-specific plasmids QpH1 and QpRS. Moreover, 1330 bp of each 16S rRNA gene were sequence-determined. All four strains multiplied at virtually the same rate and displayed the same type of vacuoles in the BGM cells. Genetic homogeneity was observed inasmuch as the 16S rDNA sequences were identical and the strains showed identical PCR amplification patterns using primers specific to enterobacterial repetitive intragenic consensus DNA sequences. The two Swedish strains and the Priscilla strain also showed identical patterns after PCR amplification of repetitive extragenic palindromic DNA sequences, whereas the Nine Mile strain demonstrated a similar, but not identical pattern. Thus, the investigated strains demonstrated very similar phenotypic and genotypic characteristics. This finding is discussed in view of the very rare occurrence of domestic Q fever in Sweden.

Animals↗

Alveolar ridge augmentation with a prototype trilayer membrane and various bone grafts: a histomorphometric study in baboons.

Barrier membranes have become a standard treatment option in alveolar ridge augmentation prior to implant placement. However, non-resorbable membranes require secondary surgery and resorbable membranes show an unfavorable degradation profile. The purpose of this study was to evaluate the potential of a slowly biodegradable/bioresorbable prototype trilayer membrane (PTLM) for supporting bone regeneration in alveolar ridge augmentation. Clinically relevant cavities were made 3 months after the extraction of the first and second molars in each jaw of six baboons. Each animal was treated with four different regimens: (1) autogenous bone block (ABB) alone, (2) ABB+PTLM, (3) deproteinized bovine bone mineral (DBBM)+PTLM and (4) no treatment. After 9 months, the baboons were sacrificed and block sections of the augmented area were subjected to histologic and histomorphometric analyses. Newly formed bone areas were determined at a distance of 1, 3, 7 and 10 mm from crestal. The data showed a well-preserved ridge profile at the membrane-protected sites, whereas non-protected bone blocks and control sites underwent severe resorption resulting in knife-edge ridge profiles. Significant differences were found between ABB+PTLM and ABB (P=0.0137-0.0232). DBBM+PTLM also produced a larger bone area compared with ABB alone (P=0.0396-0.0439). No significant difference in bone area was detectable between ABB+PTLM and DBBM+PTLM (P>0.05). The present study supports the use of the slowly biodegradable/bioresorbable PTLM with autografts and DBBM for lateral ridge augmentation in this type of bone defects.

Absorbable Implants↗

Development of an interactive multimedia-CBT-program for dental implantology and using tests of a program prototype.

The aim of the study was the development of a teaching program for dental implantology designed to improve student education as well as further training in this area. Initially, the computer equipment of German dentists was evaluated. Then, the contents of a teaching program "implantology interactive" were defined. A fully functional program prototype was developed in co-operation with a medical publishing house. Subsequently, the program was tested and statistically evaluated by 70 dental students and 40 dentists for the purpose of quality assurance. The program received extremely positive ratings with regard to design and functionality. Furthermore it was found to be clearly arranged and easy to comprehend. Even computer illiterate test persons had no problem working with the program. The biggest problem discovered during the test run was that 21% of the test persons lost their orientation while working with the program. The results of the study were used to optimize the program. For example, a graphic orientation tree was integrated, thereby improving the orientation within the program. The extremely positive reactions of the test persons leads us to expect that the introduced CBT-project will be successful. The use of the program in the student education in the dental clinic in Heidelberg and a publication in a medical publishing house are to be expected in the near future.

Attitude of Health Personnel↗

One-year prospective three-center study comparing the outcome of a "soft bone implant" (prototype Mk IV) and the standard Brånemark implant.

BACKGROUND: Oral implant treatment ad modum Brånemark has been used for decades in the rehabilitation of edentate and partially dentate patients. Posterior jaw regions frequently exhibit bone of poor texture, and it is often difficult to obtain primary stability. Thus, it may prove beneficial to deviate from the original protocol and to use implants with a modified design, for example, with a slightly tapered geometry. PURPOSE: The purpose of the investigation was to compare the early behavior of a modified (prototype Mk IV, Brånemark System, Nobel Biocare AB, Gothenburg, Sweden; test) implant with that of the standard Brånemark implant (control) in regions of mainly type 4 bone. MATERIALS AND METHODS: Three Swedish centers participated, and a total of 44 patients were treated with oral implants for 39 maxillas and 5 mandibles. The study focused on the most distal right and left implant sites (88 implants), which were randomized to receive either a test or a control implant. Various parameters were recorded, such as registered insertion torque (OsseoCare), Nobel Biocare AB), wobbling during insertion, primary and secondary stability (as measured with resonance frequency), and marginal bone loss. The implants were followed up for 1 year. RESULTS: The test implant more frequently required a higher insertion torque and showed a significantly higher primary stability than the control implant. This difference in stability leveled out over time, and test and control implants exhibited similar secondary stability at abutment operation and at the 1-year visit. Wobbling during insertion was rarely recorded for either of the implant designs. The 1-year cumulative success rate was 93.1% for test implants and 88.4% for control implants. CONCLUSIONS: The modified implant design resulted in an increased primary stability, which may be important when placing implants in jaw regions of type 4 bone. However, independent of the achieved primary stability, successful implants tended to approach similar secondary stability in the two designs tested.

Adult↗

Assessment of the cognitive effect of a prototype health education unit on sixth grade students.

The purpose of this study was to assess the cognitive effects of a prototype health education teaching model on the cardiovascular health knowledge of selected sixth grade students. The level of significance for the study was set at .05. No significant differences between pre-test mean scores, experimental to control group were found. Significant differences between post-test mean scores, experimental to control group were noted. No significant differences between control group pre-test to post-test mean scores were found. Although significant experimental group pre-test to post-test mean scores were found in all four locations, no significant differences were found between the experimental post-test mean scores by geographic location.

Achievement↗

The efficacy of two prototype chewing gums for the removal of extrinsic tooth stain.

AIM: To compare the potential efficacy of two prototype chewing gums in extrinsic stain removal on natural teeth. SETTING: Dental school clinics. DESIGN: Double-blind, two groups, parallel design. PARTICIPANTS: 76 adult volunteers (32m, 44f, mean age: 20.6 years old). METHODS: Oral hard and soft tissue health was examined. The subjects were randomly assigned to use either Product A (without active ingredients) or Product B (with active ingredients). Each subject was asked to brush their teeth for one minute twice daily (mornings and nights) and chew the gums supplied for 15 min (2 dragees each time), three times daily, once after each meal (breakfast, lunch and dinner) for the entire four-week duration. Dental stain assessment was made on the 12 incisors using the Lobene Stain Index (LSI). RESULTS: The overall difference between the stain scores after 4-weeks' use of the chewing gums was statistically significant (p<0.01) for both test Product A (10.84) and Product B (7.77) with regard to the mean baseline stain scores (21.57). This difference represented a 48% reduction in stain scores for those subjects using Product A, while the reduction was 64% for the subjects using Product B. CONCLUSIONS: The results of this in vivo study suggest that chewing gums with and without active ingredients have potential effect on stain removal after regular use for one month.

Adolescent↗

Evaluation of a prototype micro-electronic autoclave cycle integrator.

Instability and non-uniformity of spore preparations and the non-conformity of chemical indicators to the temperature coefficients of spore inactivation are problems associated with current methods of autoclave cycle monitoring. A prototype micro-electronic instrument, which largely overcomes these problems, is described. It monitors autoclave cycles in terms of the integral F0 and Nabla functions. Its thermometric and integrating accuracy is demonstrated. A discussion of the problems associated with the use of sensitive electronic instruments in the autoclave room environment reveals the need for independent monitoring areas when such devices are used. Inactivation constants were determined for spores of the organism Bacillus stearothermophilus, NCTC 10 003 and were described using D115 (12.0 min) and Z (9.0 degrees C) values and the first order reaction Arrhenius constants A 10(41.2) min-1) and Ea (74.4 kcal mol-1, 311 kJ mol-1). These have been compared with recently published values. The standardization of F0 and Nabla is discussed with reference to the setting of minimum values related to product bioburden and maximum values related to an acceptable degree of product degradation.

Electronics↗