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At least 1,009 records · Page 56Linked to original sources
PubMed1999

Phototoxicity of rose bengal in mycological media--implications for laboratory practice.

The effects of Rose Bengal (RB) on plate counts of the bacteria Escherichia coli and Pseudomonas aeruginosa, and the yeast Saccharomyces cerevisiae, were studied under natural sunlight and artificial fluorescent lighting. While RB was not inherently toxic in darkness at concentrations found in mycological media, the illumination of media containing RB caused a decrease in colony counts in all cases, and especially for surface spread plates. A negative synergy was observed between chloramphenicol, RB and illumination using a spring water sample containing substantial numbers of Gram-negative bacteria. Exposure of media containing RB to moderate amounts of light during standard laboratory procedures may inhibit microbial growth, with positive benefits in relation to the suppression of contaminant bacteria, or negative implications where fungi are inhibited.

Anti-Bacterial Agents↗
PubMed1998

Bacterial leakage into and from prefabricated screw-retained implant-borne crowns in vitro.

A mean gap of less than 4 microm following laboratory procedures and continuous loading was demonstrated in prefabricated crowns of the Ha-Ti implant system in earlier studies. The clinical relevance of such high precision in maintaining inflammation free marginal mucosa is yet to be determined. In this present investigation, the complete assembly of Ha-Ti implants including prefabricated screw-retained crowns was tested for bacterial leakage under controlled conditions in vitro. The gaps were shown not to be a barrier for Staphylococcus aureus which were used as test bacteria. Bacterial leakage through these gaps from the environment to the interior of the assembly and vice versa was observed within 24-120 h. The main path of bacterial penetration was possibly found to be through the transversal screw hole and not through the marginal gap of the prefabricated crowns.

Crowns↗
PubMed2001

Bonding strength between a hard chairside reline resin and a denture base material as influenced by surface treatment.

Direct relining of dentures made with hard chairside reline resins is faster than laboratory-processed reline systems and the patient is not without the prosthesis for the time necessary to perform the laboratory procedures. However, a weak bond between the autopolymerizing acrylic reline resins and the denture base material has been observed. This study evaluated the effect of six different surface treatments on the bond strength between a hard chairside reline acrylic resin and a heat-cured acrylic resin. Specimens of the heat-cured acrylic resin were divided into seven groups. One of these groups remained intact. In the other groups, a 10-mm square section was removed from the centre of each specimen. The bonding surfaces were then treated with (i) methyl methacrylate monomer, (ii) isobutyl methacrylate monomer, (iii) chloroform, (iv) acetone, (v) experimental adhesive and (vi) no surface treatment -- control group. Kooliner acrylic resin was packed into the square sections and polymerized. The bonding strength was evaluated by a three-point loading test. The results were submitted to one-way analysis of variance (ANOVA) followed by a Tukey multiple range test at a 5% level of significance. No significant difference was found between the surface treatment with Lucitone 550 monomer or chloroform, but both were stronger than the majority of the other groups. The bond strength provided by all the surface treatments was lower than that of the intact heat-cured resin.

Acetone↗
PubMed1998

The cost of treating paediatric malaria admissions and the potential impact of insecticide-treated mosquito nets on hospital expenditure.

OBJECTIVE: To calculate the costs at Kilifi District Hospital (KDH) and Malindi Sub-district Hospital (MSH) of treating paediatric malaria admissions including three common presentations of severe paediatric malaria, i.e. cerebral malaria, severe malaria anaemia and malaria-associated seizures; and to estimate the implications for hospital expenditure of a reduction in paediatric malaria admissions. METHODS: Patient data were obtained from hospital records. All costs were allocated to departments that provided direct patient care by a four-stage step-down procedure. Laboratory and drug costs of treating paediatric malaria admissions were separately identified. RESULT: Unit recurrent costs per admission in KDH ranged from US $57 for 'other' paediatric malaria to US $105 for cerebral malaria, and in MSH from US $33 to US $44 for the same categories. The annual recurrent cost of treating all paediatric malaria admissions to KDH prior to the trial was estimated at US $78 900. Adjusting for preintervention differences in malaria admission rates and age between intervention and control areas, the ITBN trial found a 41% reduction in paediatric malaria admissions. The reduction in admissions resulted in an estimated saving of US $6240 in the cost of treating paediatric malaria admissions from the intervention area. CONCLUSION: There would be a substantial reduction in costs of treating paediatric malaria admissions if the intervention were introduced in the whole catchment area of the hospital. Actual savings would depend on the proportion of potential savings that can in practice be realised, and on the effectiveness of the intervention when routinely implemented.

Anemia↗
PubMed2002

Effects of a water-soluble extract of maitake mushroom on circulating glucose/insulin concentrations in KK mice.

AIM: We examined benefits of a water-soluble extract of maitake mushroom designated as Fraction X (FXM) on the glucose/insulin metabolism of insulin-resistant KK mice, and compared the results of FXM with those of a sulphonylurea, Glipizide. DESIGN: In several acute studies, insulin-resistant KK mice were gavaged with a single dose of varying concentrations of FXM, or a single dose of one concentration of the oral hypoglycaemic drug, Glipizide. In the one chronic study, KK mice were gavaged with FXM, Glipizide, or an equal volume of isotonic saline (baseline control) twice daily. Retro-orbital blood was drawn on the morning of the 4th and 7th days before the early gavage. Blood glucose was measured by routine laboratory procedures, and serum insulin was estimated by a radioimmunoassay (RIA) assay developed specifically for rodents. RESULTS: At a dose of FXM (140 mg/mouse), a statistically significant lowering of circulating glucose concentrations was again seen at 8-12 h and 16-18 h after oral gavage. The lowering approximated 25% of the original concentration. Oral gavage of Glipizide resulted in statistically significantly lower values of circulating glucose (25-37% lower compared with baseline) at 8-24 h post dosing. In the chronic study, the circulating concentrations of glucose and insulin of mice taking 140 mg FXM per day were decreased significantly at days 4 and 7. CONCLUSIONS: FXM, a natural extract obtained from maitake mushroom, favourably influences glucose/insulin metabolism in insulin-resistant KK mice. The lowering of both circulating glucose and insulin concentrations suggests that FXM works primarily by enhancing peripheral insulin sensitivity.

Agaricales↗
PubMed1999

Prognostic value of sarcomatoid histology and volume-weighted mean nuclear volume in renal cell carcinoma.

OBJECTIVE: To determine the prognostic value of two histopathological factors, sarcomatoid histology and volume-weighted mean nuclear volume (MNV) in renal cell carcinoma (RCC). PATIENTS AND METHODS: The study included 106 patients (72 men and 34 women, mean age 63 years, range 32-83) with RCC, all of whom were surgically treated between 1985 and 1995. The presence of any sarcomatoid component was determined and MNV estimated using a stereological method in histological slides of tumour specimens from these patients. The prognostic significance of the two variables was evaluated by univariate and multivariate analyses in comparison with other histopathological variables (T, N and M categories, nuclear grade, tumour size, tumour type), using the cause-specific and progression-free survival of the patients as the endpoints. RESULTS: Among the 106 RCC cases examined, a sarcomatoid component was detected in 34 (32%); the MNV was 90-627 micro3 (mean 225). By univariate and multivariate analysis, both variables were significant prognostic factors for cause-specific survival in all patients. In addition, multivariate analysis of the 74 patients with localized RCCs (T1-3, N0 M0) showed that sarcomatoid histology was a significant prognostic factor for disease progression. CONCLUSION: The presence of sarcomatoid histology and the MNV, both of which can be examined with no specialized laboratory procedures, seem to be useful tumour-related prognostic factors in RCC.

Adult↗
PubMed2003

Frontal sinus obliteration with heterogeneous corticocancellous bone versus spontaneous osteoneogenesis in monkeys (Cebus apella): histologic analysis.

PURPOSE: In this study, we evaluated the results of spontaneous osteoneogenesis of the frontal sinus with autogenous bone plug versus obliteration with heterogeneous (human) bone in monkeys (Cebus apella). MATERIALS AND METHODS: Eight young adult male C apella monkeys underwent an ostectomy of the anterior wall of the frontal sinus, removal of the sinus mucosa, and inner decortication of the bony walls and then were divided into 2 groups of 4 each, as follows. Group I monkeys underwent obliteration of the nasofrontal ducts with a free segment of frontallis muscle and corticocancellous heterogeneous bone, followed by full obliteration of the sinus with corticocancellous heterogeneous bone (Dayton Regional Tissue Bank, Dayton, OH). Group II monkeys underwent obliteration of the nasofrontal ducts with a frontal muscle segment and tibial autogenous bone plug, without full obliteration of the frontal sinus. In all animals, the sinus anterior wall was repositioned and fixed with 1.0 plate and screws. The monkeys were killed after 180 days, and routine laboratory procedures were followed for hematoxylin-eosin staining and histologic evaluation of the specimens. RESULTS: The 2 studied techniques were both effective in obliterating the frontal sinus with newly formed bone. The nasofrontal ducts were obliterated by new bone formation or fibrous tissue (1 animal only). CONCLUSIONS: Both methods used for frontal sinus obliteration were effective; the heterogeneous bone (human bone) was well tolerated and presented low antigenicity. The nasofrontal duct obliteration with autogenous muscle associated with autogenous tibial bone (group II) or with heterogeneous bone (group I) was effective, isolating the frontal sinus from the nasal cavity. The spontaneous obliteration resulted, in the period analyzed, in earlier bone maturation compared with the obliteration by heterogeneous bone.

Adipose Tissue↗
PubMed1986

[Value of CA 125 in comparison to conventional tumor markers in ovarian cancer].

It was the aim of this study to evaluate the clinical significance of the monoclonal test system CA 125 in comparison to 7 conventional laboratory procedures (TPA, PHI, CEA, LDH, GGT, AP, ESR) as tumour marker in ovarian cancer. Serum samples from 327 patients with histologically proven cancer of the ovary were analysed. Marker results were correlated to tumour activity as defined by the criteria of the UICC. Furthermore, in 175/327 patients who were clinically symptom-free after primary therapy, marker courses were analysed with regard to the development of recurrence. Positive rates and median values of CA 125, TPA, PHI and ESR showed significant increases with progression of the disease, whereas correlation was less clear-cut with CEA, LDH, GGT and AP. In clinically tumour-free patients without evidence of recurrence during the further course, intermittent increases of PHI, ESR and especially TPA were found in 19-47%. However, such "false positive" marker courses were not seen with CA 125. Those patients who developed recurrent disease exhibited increasing CA 125 titres in 68%. The incidence of such "true positive" markers courses was less frequent with PHI, ESR and TPA. Our results indicate that CA 125 and--with limitations--TPA, PHI and ESR may be used in ovarian cancer control. When monitoring tumour-free patients, CA 125 exhibited the highest specificity and sensitivity. Using 65 U/ml as cut-off, a positive CA 125 titre indicates recurrent disease with great certainty. When employing PHI, ESR and especially TPA, however, the possibility of "false positive" increases has to be taken into account.(ABSTRACT TRUNCATED AT 250 WORDS)

Alkaline Phosphatase↗
PubMedDate not supplied

Streptococcal viridans subacute bacterial endocarditis associated with antineutrophil cytoplasmic autoantibodies (ANCA).

We report an illustrative case of a 60-year-old man with Streptococcus viridans subacute bacterial endocarditis (SBE) and positive antineutrophil cytoplasmic autoantibodies (c-ANCA). C-ANCA positivity has been associated with a variety of rheumatic and infectious disease areas, but has been rarely associated with SBE. The patient had mitral valve prolapse with mitral regurgitation, and S viridans SBE developed after a dental procedure. Laboratory abnormalities included anemia, elevated erythrocyte sedimentation rate, positive rheumatoid factor, positive anticardiolipin antibody, positive lupus anticoagulant, and highly elevated c-ANCA level. We believe this is only the ninth reported case of S viridans SBE with a positive c-ANCA, and the third with mitral valve prolapse and vegetations.

Anti-Bacterial Agents↗
PubMed2000

The role of spinal tissues in resisting posteroanterior forces applied to the lumbar spine.

OBJECTIVE: To determine the effects of the dissection of spinal tissues on the mechanical behavior of motion segments under the application of posteroanterior forces. DESIGN: A cadaveric motion segment study. SETTING: A tissue mechanics research laboratory. PROCEDURE: Anterior shear and extension moment were applied to 10 motion segments to simulate the clinical situation when posteroanterior forces were applied to the spine. The movements of the specimens in the sagittal plane were studied by a camera. Spinal tissues were dissected sequentially, and the mechanical testing was repeated after the dissection of each tissue. RESULTS: The most significant movements produced were extension and superior translation of the anteroinferior corner of the superior vertebral body. Translational movements in the other directions were small. The dissection of the posterior ligaments and zygapophyseal joints did not lead to significant changes in the movements. CONCLUSIONS: Injuries of the posterior ligaments are unlikely to alter the mechanical response of the spine to posteroanterior forces. However, these posterior tissues are pain sensitive and may be subjected to large strains and elicit symptoms.

Aged↗
PubMed2002

A surgical guide for accurate mesiodistal paralleling of implants in the posterior edentulous mandible.

Malaligned implants often complicate the clinical and laboratory procedures employed for the fabrication of superstructures. Due to improper load distribution, an overall increase in stress concentrations on supporting implants may occur; in the long run, this may compromise the maintenance of the bone-implant interface. The utilization of surgical stents is imperative for optimum implant installation. This article describes a modified surgical stent that serves as a guide to proper mesiodistal paralleling of dental implants.

Bicuspid↗
PubMed2002

Retrofitting crowns to an existing removable partial denture clasp: a simple technique.

The fabrication of a new crown to replace an existing abutment tooth for a removable partial denture is one of the most labor-intensive chairside and laboratory procedures. The process can become more complicated when the patient requests a tooth-colored esthetic restoration. Numerous techniques are described in the literature, some for all-metallic restorations and others for metal-ceramic restorations. This article describes a simplified technique that makes use of a polymer ceramic material.

Crowns↗
PubMed2003

Reductive genome evolution in Buchnera aphidicola.

We have sequenced the genome of the intracellular symbiont Buchnera aphidicola from the aphid Baizongia pistacea. This strain diverged 80-150 million years ago from the common ancestor of two previously sequenced Buchnera strains. Here, a field-collected, nonclonal sample of insects was used as source material for laboratory procedures. As a consequence, the genome assembly unveiled intrapopulational variation, consisting of approximately 1,200 polymorphic sites. Comparison of the 618-kb (kbp) genome with the two other Buchnera genomes revealed a nearly perfect gene-order conservation, indicating that the onset of genomic stasis coincided closely with establishment of the symbiosis with aphids, approximately 200 million years ago. Extensive genome reduction also predates the synchronous diversification of Buchnera and its host; but, at a slower rate, gene loss continues among the extant lineages. A computational study of protein folding predicts that proteins in Buchnera, as well as proteins of other intracellular bacteria, are generally characterized by smaller folding efficiency compared with proteins of free living bacteria. These and other degenerative genomic features are discussed in light of compensatory processes and theoretical predictions on the long-term evolutionary fate of symbionts like Buchnera.

Base Sequence↗
PubMed2005

Profiling the humoral immune response to infection by using proteome microarrays: high-throughput vaccine and diagnostic antigen discovery.

Despite the increasing availability of genome sequences from many human pathogens, the production of complete proteomes remains at a bottleneck. To address this need, a high-throughput PCR recombination cloning and expression platform has been developed that allows hundreds of genes to be batch-processed by using ordinary laboratory procedures without robotics. The method relies on high-throughput amplification of each predicted ORF by using gene specific primers, followed by in vivo homologous recombination into a T7 expression vector. The proteins are expressed in an Escherichia coli-based cell-free in vitro transcription/translation system, and the crude reactions containing expressed proteins are printed directly onto nitrocellulose microarrays without purification. The protein microarrays are useful for determining the complete antigen-specific humoral immune-response profile from vaccinated or infected humans and animals. The system was verified by cloning, expressing, and printing a vaccinia virus proteome consisting of 185 individual viral proteins. The chips were used to determine Ab profiles in serum from vaccinia virus-immunized humans, primates, and mice. Human serum has high titers of anti-E. coli Abs that require blocking to unmask vaccinia-specific responses. Naive humans exhibit reactivity against a subset of 13 antigens that were not associated with vaccinia immunization. Naive mice and primates lacked this background reactivity. The specific profiles between the three species differed, although a common subset of antigens was reactive after vaccinia immunization. These results verify this platform as a rapid way to comprehensively scan humoral immunity from vaccinated or infected humans and animals.

Animals↗
PubMed1988

Water-stress-induced changes in the abscisic acid content of guard cells and other cells of Vicia faba L. leaves as determined by enzyme-amplified immunoassay.

A highly sensitive, solid-phase, enzyme-amplified immunoassay for the plant growth regulator (+)-abscisic acid (ABA) was developed. The assay sensitivity (0.2-10 fmol) was sufficient for analyzing free ABA in homogeneous tissue samples dissected from Vicia faba L. leaves. Eight hours after detached leaves had been desiccated to 10% loss of fresh weight, the bulk leaf ABA content increased from </=0.2 to 6.2 ng.(mg dry weight)(-1). Epidermal tissue, spongy parenchyma cells, and palisade parenchyma cells from this water-stressed leaf had the following ABA contents, respectively: 4.8, 9.4, and 9.0 ng.(mg dry weight)(-1). Guard cells, which respond to exogenous ABA by losing solutes and volume, were also assayed. When they were dissected from control (fully hydrated) leaves, their ABA content was approximately 0.7 fg.(cell pair)(-1) [[unk]0.2 ng.(mg dry weight)(-1)]. In contrast, the ABA content of guard cells of water-stressed leaves was approximately 17.7 fg.(cell pair)(-1). These results indicate that ABA accumulation in a highly stressed V. faba leaflet is generalized; guard cells contain only 0.15% of bulk leaf ABA. The time course for loss of ABA from guard cells of a floating epidermal peel was studied. There was little loss within 30 min, but after 4 hr, the ABA content was only 17% of the original value. These results indicate that the bulk of guard cell ABA is not readily diffusible (i.e., probably not apoplastic). The results also indicate that common laboratory procedures results in lowered guard cell ABA content.

Journal Article↗
PubMed1992

Population genetics in the forensic DNA debate.

The use of matching variable number of tandem repeat (VNTR) profiles to link suspects with crimes is potentially very powerful, but it has been quite controversial. Initial debate over laboratory procedures has largely given way to debate over the statistical and population genetic issues involved in calculating the frequency of a profile for a random member of a population. This frequency is used to weight the evidence of a match between suspect and crime scene material when the suspect denies responsibility for that material. A recent report from the National Research Council, intended to put to rest some of the issues, has instead raised further debate by advocating a procedure based on maximum frequencies of profile components over several different populations.

Alleles↗
PubMed1995

Exponential increases of RNA virus fitness during large population transmissions.

The great adaptability shown by RNA viruses is a consequence of their high mutation rates. Here we investigate the kinetics of virus fitness gains during repeated transfers of large virus populations in cell culture. Results always show that fitness increases exponentially. Low fitness clones exhibit regular increases observed as biphasic periods of exponential evolutionary improvement, while neutral clones show monophasic kinetics. These results are significant for RNA virus epidemiology, optimal handling of attenuated live virus vaccines, and routine laboratory procedures.

Animals↗