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PubMed1996

Blood type AB in the feline AB blood group system.

OBJECTIVE: To assess the genetics, frequency, and biochemistry of the AB blood type in cats. ANIMALS: Domestic shorthair and purebred cats in a breeding colony and privately owned catteries and blood samples from a large feline blood typing laboratory. PROCEDURES: Samples from cats with blood type AB were selected from the feline blood typing laboratory at the university. Breeding experiments and family studies were used for the genetic analysis of cats with blood type AB. Simple slide hemagglutination assays were used to type cats. Hemagglutination assays, flow cytometry, and ganglioside analysis by high-performance thin layer chromatography were applied to characterize the AB antigens. RESULTS: Type AB was rare (13/9,239 cats; 0.14% frequency) in cats of the United States and Canada. Type AB occurred only in breeds in which type B was also detected. Cats with type-AB blood express biochemical features of type-A and type-B antigens. Genetic analyses of families with blood type-AB cats are consistent with the hypothesis of 3 alleles: A, B, and AB. The AB allele is recessive to the A allele, but dominant over the B allele. There may be an additional genetic mechanism responsible for the inheritance of blood type AB in cats. CONCLUSION: Blood type AE is an extremely rare and separately inherited type in the feline AB blood group system. CLINICAL RELEVANCE: Kittens with type-AB blood born to queens with type-B blood are at similar risk for neonatal isoerythrolysis as kittens with type-A blood because anti-A alloantiserum from blood type-B queens recognizes AB red blood cells. Furthermore, cats with type-AB blood are best transfused with type-AB or type-A blood.

ABO Blood-Group System↗
PubMedDate not supplied

Laboratory diagnosis of gonorrhea by a simple transformation test with a temperature-sensitive mutant of Neisseria gonorrhoeae.

A temperature-sensitive mutant of Neisseria gonorrhoeae strain tsA-1 was used in a transformation test for the laboratory diagnosis of gonorrhea. This transformation test (C test) is based on a spotting of a DNA lysate, obtained through simple base-acid extraction of a cervical-swab specimen, onto a lawn of tsA-1, which is then incubated for one to two days at 37 C. Of 1,053 cervical-swab specimens tested, 52 contained the gonococcal DNA necessary for restoring the ability of tsA-1 to grow well at 37 C; 49 of the 52 specimens were identified as N. gonorrhoeae by routine diagnostic laboratory procedures. The time required for the C test is two to three days, which is shorter than that required for routine diagnostic laboratory tests, and the C test involves a minimum of common laboratory supplies and expertise. The discrepancies between results of the C test and routine procedures are explained as follows. In one case an isolate suspected to be N. gonorrhoeae was nonreactive in the sugar fermentation test, and in two cases the agar plates were overgrown with yeasts; neither situation affected the C test.

Bacteriological Techniques↗
PubMed2005

A comparison of prenatal versus postnatal karyotyping for the investigation of intrauterine fetal death after the first trimester of pregnancy.

INTRODUCTION: Aneuploidy is an important cause of intrauterine fetal death (IUFD) after the first trimester. Determination of the fetal karyotype of these pregnancies is commonly done in most units from solid tissues. Results from such techniques are disappointing. The aim of this audit was to compare the results of karyotyping IUFD by invasive testing (amniocentesis or chorionic villus sampling) and solid tissues (skin biopsy). SUBJECTS AND METHODS: Women with IUFD managed in our unit between 1 January 1998 and 31 December 2002 (inclusive) were offered either invasive testing before medical induction of labour or solid tissue biopsy after delivery. The amniotic fluid, chorionic villi and biopsies were processed following standard laboratory procedures. RESULTS: During the 60 months, 230 samples from cases of IUFD were received by the laboratory in our unit; 126 had skin biopsies and 104 underwent invasive testing (81 amniocenteses and 23 chorionic villus sampling). Successful karyotyping was possible in 90% of those who underwent amniocentesis, 100% of those who had chorionic villus sampling and 13.5% of those who had skin biopsies. 50% of skin biopsies were unsuitable for analysis compared to none in the CVS and amniocentesis group. The difference in successful karyotyping between invasive testing and solid tissue testing was statistically significant (P < 0.0001). There were 12 (10.6%) abnormal karyotypes from the 113 successful samples (11/96 in the invasive group versus 1/17 in the solid tissue group). CONCLUSION: Invasive testing has a much higher success rate of karyotyping in cases of IUFD and should, therefore, be offered to women presenting with this complication irrespective of gestational age.

Amniocentesis↗
PubMed2003

Laboratory-processed acrylic resin provisional restoration with cast metal substructure for immediately loaded implants.

Most methods of immediate loading of implants reported in the literature involve retrofitting a pre-existing denture to the implants. This article describes and illustrates clinical and laboratory procedures for immediate loading of implants in the edentulous mandible with the use of a laboratory-processed, provisional, screw-retained, implant-supported fixed complete denture that incorporates a cast metal reinforcement.

Dental Alloys↗
PubMed1998

Development and clinical applications of a light-polymerized fiber-reinforced composite.

STATEMENT OF PROBLEM: After 0 years of intermittent reports in the literature, the use of fiber reinforcement is just now experiencing rapid expansion in dentistry. PURPOSE: This article describes the development and use of a continuous, unidirectional fiber reinforced composite as a framework for the fabrication of fixed prostheses. METHODS: By using various matrix materials and fibers, a number of fiber-reinforced composite formulations were evaluated with the goal of creating a system with optimized mechanical properties and handling characteristics. Fiber-reinforced composite based on a light polymerized BIS-GMA matrix has been used clinically to make 2-phase prostheses comprised of an internal glass fiber-reinforced composite substructure covered by a particulate composite. The clinical and laboratory procedures required for the fabrication and use of reinforced composite fixed prostheses are described for laboratory-fabricated complete or partial coverage fixed prosthesis and chairside prosthesis. RESULTS: Although additional clinical experience is needed, fiber-reinforced composite materials can be used to make metal-free prostheses with excellent esthetic qualities.

Bisphenol A-Glycidyl Methacrylate↗
PubMed1995

Fabrication of a duplicate denture from an existing complete denture.

A technique is presented that describes the fabrication of a duplicate denture using the patient's existing complete denture. This procedure enables the practitioner to offer patients an alternative to being without a denture during a laboratory reline of an existing denture. A vinyl polysiloxane impression material is used to impress the polished surface of the existing denture as well as to block out undercuts on the impression surface of the denture before pouring a stone cast. Because of the stability of the impression material used, most of the laboratory procedures can be accomplished separate from the clinical appointment.

Acrylic Resins↗
PubMed2004

Critical steps in the implementation of hematopoietic progenitor-cell gene therapy using ribozyme vectors: a laboratory protocol.

The implementation of a hematopoietic progenitor-cell gene-therapy program involves the performance of laboratory procedures and compliance with the current code of Good Manufacturing Practices. This chapter explains the multiple laboratory steps used in our recent Phase I gene transfer study for HIV. This study employed a retroviral vector to deliver an anti-HIV ribozyme to CD34+ hematopoietic progenitor cells.

Genetic Therapy↗
PubMed1983

Nosocomial patient-related laboratory abuse.

Improper and excessive use of laboratory procedures constitute a significant waste of money. This article describes a number of common forms of laboratory abuse and attempts to alleviate the headaches with a dash of humor.

Health Services↗
PubMed2000

[Developmental frontier of a modular automated system].

The clinical laboratory is faced with increasing problems such as healthcare reform, cost pressure and increased laboratory regulations. Despite these problems, the users have even higher expectations for laboratory services. To resolve these issues, the clinical laboratory must become more efficient by incorporating creative solutions and adapting to changes. One key word is increased automation of laboratory procedures and integration of automated systems. First, automation will reduce the dependence on manual labor. Second, laboratories could perform a larger menu of tests in-house. This not only reduces expense but also reduces the turn around time for testing. To realize cost reduction and reduce turn around time, we propose the Modular system.

Automation↗
PubMedDate not supplied

Synergistic relationship between luting and priming agents and gold restorations plated with stannic oxide.

Bonding to dentin and enamel has increased restorative treatment options, provided the materials are used to optimum advantage. Restorative dentists must understand the indications and the proper mechanisms for using these materials. As with many techniques and procedures, it takes more time to describe than to accomplish. The tooth-conditioning and cementing steps are standard treatment procedures used daily in most dental offices. Tin-plating and preparing the metal surface are laboratory procedures and consume no chair time. The clinical advantages of bonding--such as resistance to microleakage and recurring decay, enhanced retention, preservation of tooth structure, and extended restoration prognosis--far outweigh the modest increase in placement time.

Cementation↗
PubMed1996

Prediction of the net energy content of raw materials and compound feeds for ruminants by different laboratory methods.

In this study three different laboratory procedures were compared as predictors of net energy content of raw materials and compound feeds for ruminants. Laboratory measurements included an enzymatic technique (pepsin-cellulase method) and a rumen fluid technique (Hohenheim gas test). An estimate based on crude nutrients only was also tested. A total of 98 feed samples with known in vivo digestibility were available. By multivariate regression analysis equations for the prediction of the net energy content were calculated. The results suggest that in case of compound feeds for dairy the cellulase technique and the gas test are suitable in vitro techniques. With both procedures the relationships between energy contents estimated in vitro and energy contents measured in vivo showed residual errors of less than 4 percent. However for the evaluation of raw materials the gas test was superior. Compared to the cellulase technique the risk of extreme under- or overestimations is apparently reduced and this was found to be the case for own prediction equations as well as equations from literature. Crude nutrients proved to be very poor predictors for all feed samples.

Animal Feed↗
PubMed1992

The role of the laboratory in the prevention and detection of chronic disease.

Laboratory Initiative For The Year 2000 (LIFT), the laboratory response to the Healthy People 2000 program, includes the following in its definition of chronic disease: cancer, diabetes, hypertension, end-stage renal disease, stroke, and cardiovascular disease. All are priority health targets for which the laboratory must play an active support role if we are to achieve the goal of controlling these diseases by the year 2000. What are the laboratory procedures needed to assist in the prevention and detection of chronic disease? In this review I consider the traditional tests now used in these efforts, emphasize how and where screening for diabetes, cardiovascular disease, and cancer is now done, and describe the current status of the clinical laboratory in supporting these activities, including new and promising procedures that may be useful in identifying individuals at high risk for disease. It is important to initiate good clinical laboratory practice for these new tests as they are transferred from the research laboratory to the clinical laboratory. The laboratory will be required to provide for this need rapidly and at the same time comply with federal and state controls and regulations.

Cardiovascular Diseases↗
PubMed2004

Method to quantify tail vein injection technique in small animals.

Injection errors, which are often not readily recognized, can greatly impact the outcome of a pre-clinical research study. As a result, unrecognized misadministration of test compounds can render a high cost to the biomedical community. In this report, we propose six criteria for a reagent designed to assess tail vein injection technique in small animals and suggest a reagent, colloidal gold labeled with the stable isotope 197Au, that satisfies these criteria, thereby describing and validating for the first time a method to quantify technical compliance in tail vein injections. In an application of this reagent, we show the degree of variation experienced by technologists performing tail vein injection procedures in mice. In this study, mice were manually restrained and received an injection in the tail vein. One hour after injection, the mice were euthanized, various organs including the tail (the site of the injection) were collected, and their gold content was quantified by neutron activation. The three experienced animal technologists in the study were tested for tail vein injection proficiency in 30 mice. Prior to the study, the supervisor stated that a misinjection occurs when more than 10% of the intended volume remains in the tail. In light of this criterion, 12 of the 30 injections were misadministered: two with technologist 1, three with technologist 2, and seven with technologist 3. Although she was able to correctly rank the injection skills of the three technologists used in this experiment, i.e., technologist 1 and 2 more better skilled than technologist 3, the supervisor greatly underestimated the extent and degree of injection failures for the procedure. The results of the study illustrate the potential problems associated with the technical compliance with this common laboratory procedure and suggest that there is a need to validate injection methods and a need to monitor technical competence. Application of reagents similar to colloidal gold and the methods presented will facilitate the development of improved methods of teaching injection technique and monitoring technical quality in the laboratory setting. In Vivo Micro Computed Tomography of Subchondral Bone in the Rat After Intra-articular Administration of Monosodium Iodoacetate

Animals↗
PubMed1980

A multivariate approach to laboratory practice.

The application of multivariate statistical technics to laboratory data analysis is a recent development in clinical pathology. The proliferation in number and type of diagnostic tests requires a simple method to extract predictors of clinical states from data generated by existing laboratory procedures, as well as a method to assess the usefulness of new tests as they are proposed. A series of algorithms can select a "best predictor" subset of laboratory tests and verify this reduced group's predictive diagnostic worth. The established predictive ability of existing laboratory tests can serve as a reference scale when a newly available laboratory test is evaluated. The proposed new test is included with the best predictors already identified and confirmed. In multivariate analysis the usefulness of the proposed new procedure in the predictive diagnosis scheme is determined.

Clinical Laboratory Techniques↗
PubMed1978

Methods of cost control in urologic care.

The urologist now has the capability of significantly reducing the cost of care for his patients. Major savings could occur by performing procedures, laboratory tests, and roentgenographic studies in proper sequence. The use of outpatient evaluations and surgery can save the patient expensive hospital room charges. Proper utilization of equipment would markedly decrease costly duplication of services. Quality of care cannot and will not be affected by these cost-saving measures. Furthermore, retrospective and prospective clinical studies should be instituted immediately to determine the pathophysiology of genitourinary disease, specifically answering the question of which laboratory tests have the highest diagnostic yield. Protocols could be started to eliminate wasteful low-yield procedures and to maximize diagnosis and therapy while minimizing cost. Finally, controls must be placed on the continuing trend toward an excess of physicians.

Ambulatory Care↗
PubMed1981

[Immunology and joint disease (author's transl)].

The present view is concerned with a number of joint diseases occurring in man and pets, the pathogenesis of which is (partly) immunological. This review is preceded by the discussion of a relevant part of immunology. The diagnostic laboratory procedures dealt with in the paper consist in diagnostic routine tests performed in (medical) clinico-immunological laboratories. With a few exceptions, it appears to be possible to establish a diagnosis of similar diseases in animals using comparable methods. A reliable diagnosis of these joint diseases in pets is not only of importance from the point of view of comparative nosology, but may also revive interest in the animal as a model of these forms of disease. Finally, human so-called seronegative spondylo-arthropathy associated with the presence of particular tissue antigen, is briefly discussed. Similar associations in pets such as dogs should also be studied.

Animals↗
PubMed1992

Laboratory evaluation of adhesive systems.

Adhesive bonding of resin materials to acid-conditioned enamel is a clinically proven technique in preventative, restorative, and orthodontic procedures. Laboratory evaluations of etched-enamel resin bonding have shown excellent bond strengths and the virtual elimination of marginal microleakage. Adhesion to dentin has been more of a challenge. Earlier-generation dentin bonding systems did not yield high bond strengths in the laboratory or prevent marginal microleakage. Newer-generation adhesive systems generally use a dentin conditioner to modify or remove the smear layer and a subsequent application of an adhesive resin bonding agent. Laboratory evaluations of newer systems have shown bond strengths that approach or actually exceed that of etched enamel resin bonding. Bond strengths have improved with the evolution of dentin bonding systems, and microleakage from the cementum/dentin margin has been significantly reduced or prevented with the newer systems. Although laboratory testing of adhesive systems provides a mechanism to screen and compare newly developed systems, clinical trials are essential to document long-term clinical performance.

Adhesives↗
PubMed2003

Analysis of wine components in Cynthiana and Syrah wines.

Red wine is composed of a complex matrix of compounds that can interfere with analysis. A high-performance liquid chromatography (HPLC) procedure was developed to efficiently analyze organic acids, sugars, glycerol, and ethanol in Cynthiana (Vitis aestivalis) wine. Standard laboratory procedures (pH, titratable acidity, and color attributes) and HPLC were found reproducible for Cynthiana wine. HPLC recovery efficiency was determined by analysis of spiked and unspiked samples (model, Cynthiana, and Syrah (Vitis vinifera) wines). Although recovery of components was greater in the model wine, recovery in Cynthiana and Syrah wine was comparable. The HPLC procedure was further compared to commercial rapid enzyme analysis tests using model, Cynthiana, and Syrah wines. HPLC analyses were more accurate than enzymatic tests for determining components in the model, Cynthiana, and Syrah wines. Considering the complexity of the wines analyzed, reproducibility and recovery of the HPLC procedure was demonstrated and showed improvement and precision when compared to existing methods.

Carbohydrates↗