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Identification of avian infectious bronchitis virus by direct automated cycle sequencing of the S-1 gene.

Direct automated cycle sequencing (DACS) of a reverse transcription-polymerase chain reaction (RT-PCR) product of the S-1 subunit of the spike peplomer gene was used to identify infectious bronchitis virus (IBV) serotypes. Degenerate primers CK4 and CK2, utilized previously in our laboratory, were selected for DACS because they successfully amplify a wide range of serotypes represented by various reference strains and field isolates and the resulting polymerase chain reaction (PCR) product contains diagnostically relevant S-1 sequences that can be used to identify the serotype of IBV. The S-1 nucleotide sequences generated by DACS were aligned and analyzed with commercial software to determine their relationship to the S-1 nucleotide sequences of IBV strains on deposit in the GenBank and EMBL databases. Reference strains Massachusetts (Mass) 41, Connecticut (Conn), Arkansas (Ark) DPI, JMK, and DE/072/92 were initially tested by DACS to establish the feasibility of the procedure. The DACS procedure was further evaluated with a panel of "unknowns" comprised of IBV reference strains, field isolates, and variant serotypes collected by our laboratory. The DACS procedure provided high-quality and reproducible S-1 sequence for all IBV serotypes tested, including variant serotypes that had not been sequenced previously. The S-1 nucleotide sequences for the amplified PCR products of reference strains Mass 41, Conn, Ark DPI, JMK, and DE/072/92 generated by DACS were highly homologous (>99% nucleotide identity) with their respective GenBank database sequences. In the unknown panel, the nucleotide identities of the DACS S-1 sequences of field isolates of serotypes previously identified by virus neutralization were also found to be very high (> or = 95.5%) after alignment with database sequences. In contrast, the nucleotide identities of S-1 sequences of variant serotypes 37, 3330, and PA/1220/98 and reference strain Clark 333, for which database sequences were not available, ranged from 27.7% to 73.8%, well below the identity values for a homologous serotype. With alignment software, the identities of strains in mixtures of RNAs of two different serotypes were not resolvable. DACS of IBV S-1 RT-PCR products will enable researchers to rapidly identify field strains, including new, previously unrecognized variant virus serotypes.

Amino Acid Sequence↗

Comparison of two commercial systems (Vitek and MicroScan-WalkAway) for antimicrobial susceptibility testing of Pseudomonas aeruginosa isolates from cystic fibrosis patients.

Antimicrobial susceptibility testing of cystic fibrosis (CF) isolates of Pseudomonas aeruginosa is difficult because the organisms are often mucoid and slow-growing. This study of 498 CF strains examined the correlation of results derived from two commonly used commercial systems (Vitek, MicroScan-WalkAway) with a reference method for 10 antimicrobials. Correlation to reference results was unacceptably low for all agents and both commercial systems had a high rate of very major (false-susceptible) errors. Although mucoid strains produced a 4.8% greater intermethod error, it was not markedly different than non-mucoid strains for the Vitek System. Overall, these tested commercial systems performed poorly for CF isolates in contrast to earlier reported, high correlations with the reference methods (broth microdilution frozen panels and agar dilution) of the National Committee for Clinical Laboratory Standards, the standardized disk diffusion test, and the Etest (AB BIODISK, Solna, Sweden).

Aminoglycosides↗

Reproducibility of the diagnosis of atypical endometrial hyperplasia: a Gynecologic Oncology Group study.

BACKGROUND: Most gynecologists determine therapy based on current International Society of Gynecologic Pathologists (ISGP)/World Health Organization classification of endometrial hyperplasia, the reproducibility of which has been questioned. The Gynecologic Oncology Group (GOG) initiated a protocol to assess the efficacy of hormonal therapy of atypical endometrial hyperplasia (AEH). Primary goals of the first phase (Part A) were to prospectively determine reproducibility of referring institution's pathologist's diagnosis of AEH by a panel of 3 gynecologic pathologists and to determine reproducibility of diagnoses by panel members. METHODS: Three hundred six women were entered on this protocol with a referring institution's pathologist diagnosis of AEH based on biopsy or curettage. Available slides were assessed independently and interpreted by each of a panel of 3 gynecologic pathologists who used International Society of Gynecologic Pathologists (ISGP)/World Health Organization criteria. The majority diagnosis was based on diagnostic concordance by at least 2 of the 3 panelists. RESULTS: The referring institution's pathologist's diagnosis of AEH was supported by the majority of the panel in only 38% of cases. Overall kappa value for the panel diagnosis of AEH was 0.28. The majority diagnosis was adenocarcinoma in 29%, cycling endometrium in 7%, and nonatypical hyperplasia in 18% of cases. Unanimous agreement for any diagnosis was reached among all 3 of the panel in 40% of cases. For the panel, paired kappa values for any diagnosis ranged 0.34-0.43, with an overall kappa value of 0.40. CONCLUSION: Reproducibility of referring institution's pathologists' diagnosis of AEH by a panel of gynecologic pathologists is poor. Both underestimation and overestimation of the severity of the lesion are very common. The level of reproducibility among subspecialist panel members for diagnosis of AEH in these specimens also is poor. Better criteria and better sampling are needed to improve reproducibility of this diagnosis, particularly if it is to be used for clinical decisions.

Adult↗

Recognition of DP determinants with typing reagents prepared with lymphocytes from Dutch unrelated individuals.

In an attempt to make our own set of DP typing reagents, we used lymphocytes from 12 unrelated donors, who were all HLA-A1,2; B7,8; DR2,3; DQW1,2. They all had been previously typed for DP using a reference set of well established reagents obtained from Dr. S. Shaw (NIH, Bethesda). Thirty-six promising responder-stimulator combinations were primed in bulk MLC and tested for their specificity in secondary MLC. All reagents gave reaction patterns which were concordant with the sensitizing DP types, with the exception of those combinations where a donor was used in which DR2 appeared to be associated with a non-DW2 HLA-D type. Over 1,200 reactions obtained with the new reagents were compared with those obtained with the established ones, in six different experiments. High correlation coefficients (r values) were found between the two kinds of reagents. The typings of a panel of individuals with the reference set and with our new typing set revealed an excellent agreement for DP assignments with the two sets, with the exception of the specificity DP4. The DP gene frequencies for random Dutch Caucasoids were defined.

Gene Frequency↗

Evaluation of the MicroScan rapid neg ID3 panel for identification of Enterobacteriaceae and some common gram-negative nonfermenters.

The MicroScan Rapid Neg ID3 panel (Dade Behring, Inc., West Sacramento, Calif.) is designed for the identification of gram-negative bacilli. We evaluated its ability to accurately identify Enterobacteriaceae that are routinely encountered in a clinical laboratory and glucose nonfermenting gram-negative bacilli. Using 511 stock cultures that were maintained at -70 degrees C and passaged three times before use, we inoculated panels according to the manufacturer's instructions and processed them in a Walk/Away instrument using version 22.01 software. The time to identification was 2 h and 30 min. All panel identifications were compared to reference identifications previously determined by conventional tube biochemicals. At the end of the initial 2.5-h incubation period, 405 (79.3%) identifications were correct. An additional 49 (9.6%) isolates were correctly identified after required additional off-line biochemical tests were performed. Thus, at 24 h, 88.8% of the 511 strains tested were correctly identified. Twenty-two (4.3%) were identified to the genus level only. Twenty-six (5.1%) strains were misidentified. Because the system is based on fluorogenics, there are no conventional tests readily available with which to compare possibly incorrect reactions. Of the 28 Salmonella strains that were tested, 5 were incorrectly reported. The 21 remaining errors were scattered among the genera tested. Testing on nine strains gave a result of "no identification" (very rare biotype). The Rapid Neg ID3 panel in this study approached 89% accuracy for the identification of gram-negative organisms encountered in the hospital laboratory.

Bacterial Typing Techniques↗

The role of cost-effectiveness analysis in health and medicine. Panel on Cost-Effectiveness in Health and Medicine.

OBJECTIVE: To develop consensus-based recommendations guiding the conduct of cost-effectiveness analysis (CEA) to improve the comparability and quality of studies. The recommendations apply to analyses intended to inform the allocation of health care resources across a broad range of conditions and interventions. This article, first in a 3-part series, discusses how this goal affects the conduct and use of analyses. The remaining articles will outline methodological and reporting recommendations, respectively. PARTICIPANTS: The Panel on Cost-Effectiveness in Health and Medicine, a nonfederal panel with expertise in CEA, clinical medicine, ethics, and health outcomes measurement, was convened by the US Public Health Service (PHS). EVIDENCE: The panel reviewed the theoretical foundations of CEA, current practices, and alternative procedures for measuring and assigning values to resource use and health outcomes. CONSENSUS PROCESS: The panel met 11 times during 2 1/2 years with PHS staff and methodologists from federal agencies. Working groups brought issues and preliminary recommendations to the full panel for discussion. Draft recommendations were circulated to outside experts and the federal agencies prior to finalization. CONCLUSIONS: The panel's recommendations define a "reference case" cost-effectiveness analysis, a standard set of methods to serve as a point of comparison across studies. The reference case analysis is conducted from the societal perspective and accounts for benefits, harms, and costs to all parties. Although CEA does not reflect every element of importance in health care decisions, the information it provides is critical to informing decisions about the allocation of health care resources.

Advisory Committees↗

[Evaluation of the desaturated Panel D-15. II: Comparison between the desaturated Panel D-15 and Farnsworth 100-hue tests].

The color vision was examined in 319 subjects in a comparative manner by means of the desatured Panel D-15 and Farnsworth 100-hue test used as reference test. The results expressed by scoring, were as follows: 1) a strong correlation (r = 0.80) was evidenced between the 2 tests; 2) the probable scores of the desaturated Panel D-15 were predicted from the 100-hue scores, by means of a suitable regression equation; thus allowing the calculation of norms of the desaturated Panel D-15 by reference to the well-established norms according to age of the 100-hue test; 3) the normal or pathological character of the scores of the desaturated Panel D-15 was infered from these norms, and was in good agreement with the scores of 100-hue test (K = 0.68); 4) the normal or pathological character of the qualitative patterns of the desaturated Panel D-15 was also infered from the scores; so: the minor errors were normal from 30 years old patients; a single diametral error is normal; 3 or 4 diametral errors are normal from 65 years old patients.

Adolescent↗

Blockade of hippocampal nicotinic receptors impairs working memory but not reference memory in rats.

In a three-panel runway task, intrahippocampal injection of the nicotinic receptor antagonist, mecamylamine (10 and 18 micrograms/side), significantly increased the number of errors (attempts to pass through two incorrect panels of the three panel-gates at four choice points) in a test of working memory. This increase in errors also occurred after rats were given IP mecamylamine (10 mg/kg). Mecamylamine did not affect the number of errors in a test of reference memory whether it was given at doses up to 18 micrograms/side intrahippocampally or up to 10 mg/kg IP. These results suggest that mechanisms mediated by hippocampal nicotinic receptors play a role in working memory but not in reference memory.

Animals↗

Evaluation of the PASCO strep plus broth microdilution antimicrobial susceptibility panels for testing Streptococcus pneumoniae and other Streptococcal species.

Antimicrobial resistance continues to increase worldwide among isolates of Streptococcus pneumoniae and other species of streptococci. Increasing rates of penicillin resistance, particularly in viridans group streptococci, and resistance to multiple classes of antimicrobial agents, including beta-lactams, macrolides, and fluoroquinolones, in pneumococci have increased the importance of having accurate antimicrobial susceptibility testing results for guiding therapy. One commercial method of assessing resistance in streptococci is the PASCO Strep Plus panel. This broth microdilution-based method has recently been expanded to include a variety of newer antimicrobial agents. Therefore, we compared the results of the new PASCO Strep Plus panels for 26 antimicrobial agents against the results generated using the National Committee for Clinical Laboratory Standards (NCCLS) broth microdilution reference method for 75 pneumococci and 68 other streptococcal isolates. Only 4 (0.2%) very major errors (all with pneumococci and each with a different antimicrobial agent) were observed. There were 5 (0.3%) major errors observed with pneumococci (each with a different antimicrobial agent), but only 1 major error with nonpneumococcal streptococci. All of the very major and major errors resolved on retesting. Of the 65 (3.9%) and 17 (1.6%) minor errors observed with pneumococci and other streptococci, respectively, all were within 1 dilution of the broth microdilution reference MIC result. Thus, the PASCO Strep Plus panel has comparable accuracy to the NCCLS broth microdilution reference method.

Anti-Bacterial Agents↗

[Evaluation of desaturated Panel D-15. III. Evaluation of the validity of the desaturated Panel D-15].

The estimation of the validity of a test refers to whether this test measures what it claims to measure. The validity of the desaturated panel D-15 was estimated in 248 subjects with congenital hereditary dyschromatopsia. The method used was based on a qualitative and quantitative study of the so-called lines of confusion joining the positions of the colored caps on the classical Farnsworth's diagram. The qualitative estimation was evaluated according to the prevailing number of lines of confusion which were parallel to a given line of reference of the diagram; it was related to the axis of the dyschromatopsia. The comparison of the results with results of Nagel's anomaloscope used as a reference test, demonstrated an overvaluation of the number of the protan subjects (anomaloscope: 77; desaturated D-15: 107) and an undervaluation of the number of deutan subjects (anomaloscope: 169; desaturated D-15: 70). This kind of discrepancy was not apparent with the standard Panel D-15. The quantitative estimation was evaluated according to the whole number of lines of confusion whatever their directions; it was related to the severity of the dyschromatopsia. The comparison of the results with the results of Nagel's anomaloscope demonstrated that the dichromatic and extreme anomalous trichromatic subjects nearly always (40 subjects out of 42) had 7 lines of confusion, or more; the simple anomalous trichromatic subjects had a variable number of lines of confusion, from 1 to 8, without any prevalence in the great majority of cases (193 subjects out of 204).(ABSTRACT TRUNCATED AT 250 WORDS)

Color Perception Tests↗

Recommended test panel for differentiation of Klebsiella species on the basis of a trilateral interlaboratory evaluation of 18 biochemical tests.

Klebsiella pneumoniae and Klebsiella oxytoca are the two most frequently encountered Klebsiella species giving rise to infections in humans, but other Klebsiella species can also be found in clinical specimens: Klebsiella ozaenae, Klebsiella rhinoscleromatis, Klebsiella terrigena, Klebsiella planticola, Klebsiella ornithinolytica, and Enterobacter aerogenes (Klebsiella mobilis). However, many of these species are indistinguishable by the conventional methods employed routinely in the clinical microbiological laboratory. Several investigators have suggested various additional tests, but as yet there is no standardized test panel for identifying all Klebsiella species and subspecies. In the present study, performed in three national Klebsiella reference laboratories, we have evaluated a test panel consisting of 18 biochemical tests on 242 strains comprising all Klebsiella species and subspecies. The test panel was designed to identify organisms preliminarily identified as belonging to the genus Klebsiella on the basis of conventional methods or automated identification systems. With the described test panel it is possible to find one or more positive test results differentiating any Klebsiella species, except Klebsiella rhinoscleromatis, from its closest relative.

Denmark↗

The clinical effectiveness and cost-effectiveness of screening for anal squamous intraepithelial lesions in homosexual and bisexual HIV-positive men.

CONTEXT: Homosexual and bisexual men infected with human immunodeficiency virus (HIV) are at increased risk for human papillomavirus-related anal neoplasia and anal squamous cell carcinoma (SCC). OBJECTIVE: To estimate the clinical benefits and cost-effectiveness of screening HIV-positive homosexual and bisexual men foranal squamous intraepithelial lesions (ASIL) and anal SCC. DESIGN: Cost-effectiveness analysis performed from a societal perspective that used reference case recommendations from the Panel on Cost-Effectiveness in Health and Medicine. A state-transition Markov model was developed to calculate lifetime costs, life expectancy, and quality-adjusted life expectancy for no screening vs several screening strategies for ASIL and anal SCC using anal Papanicolaou (Pap) testing at different intervals. Values for incidence, progression, and regression of anal neoplasia; efficacy of screening and treatment; natural history of HIV; health-related quality of life; and costs were obtained from the literature. SETTING AND PARTICIPANTS: Hypothetical cohort of homosexual and bisexual HIV-positive men living in the United States. MAIN OUTCOME MEASURES: Life expectancy, quality-adjusted life expectancy, quality-adjusted years of life saved, lifetime costs, and incremental cost-effectiveness ratio. RESULTS: Screening for ASIL increased quality-adjusted life expectancy at all stages of HIV disease. Screening with anal Pap tests every 2 years, beginning in early HIV disease (CD4 cell count >0.50 x 10(9)/L), resulted in a 2.7-month gain in quality-adjusted life expectancy for an incremental cost-effectiveness ratio of $13,000 per quality-adjusted life year saved. Screening with anal Pap tests yearly provided additional benefit at an incremental cost of $16,600 per quality-adjusted life year saved. If screening was not initiated until later in the course of HIV disease (CD4 cell count <0.50 x 10(9)/L), then yearly Pap test screening was preferred due to the greater amount of prevalent anal disease (cost-effectiveness ratio of less than $25,000 per quality-adjusted life year saved compared with no screening). Screening every 6 months provided little additional benefit over that of yearly screening. Results were most sensitive to the rate of progression of ASIL to anal SCC and the effectiveness of treatment of precancerous lesions. CONCLUSIONS: Screening HIV-positive homosexual and bisexual men for ASIL and anal SCC with anal Pap tests offers quality-adjusted life expectancy benefits at a cost comparable with other accepted clinical preventive interventions.

Adult↗

Multicenter evaluation of strategies for serodiagnosis of primary infection with Toxoplasma gondii.

The diagnostic performance of single-serum assays for toxoplasma-specific immunoglobulin (Ig)M. IgA. IgG, and IgE antibodies and of different combinations of such antibody assays in 20 European reference centers was assessed. A panel of 276 sera, of which 73 came from patients who seroconverted within 3 months (acute infection), 49 from patients who had seroconverted 3-12 months earlier (convalescence), and 154 from subjects who had two IgG-positive samples obtained 12 months apart (past infection), was tested with 20 toxoplasma-antibody assays and 195 combinations. In general, every assay with high diagnostic sensitivity showed low diagnostic specificity, i.e. no assay performed alone could reliably distinguish acute from past infection. Furthermore, no single assay (or combination) could separate convalescence from the other stages of toxoplasma infection. However, excellent diagnostic performances were reached by sequential use of highly sensitive IgM assays and methods examining IgG avidity or stage specificity. IgA or IgM assays were less suitable for confirmation of toxoplasma-IgM positivity. This study documents the strength of test combinations in assessing the stage of toxoplasma infection.

Acute Disease↗

Carbohydrates as recognition molecules for bacterial adhesins: methodology and characteristics.

Future attempts at developing inhibitors of dental plaque formation necessitate characterization of the bacterial-host, as well as the inter-bacterial recognition processes. Bacterial binding to a panel of solid-phase reference glycolipids was used to reveal the recognition of internal receptor sequences, low-affinity cooperative interactions, and adhesin variants with slightly shifted receptor epitopes. This epitopic variation may be a mechanism for shifting the host and tissue tropism of the bacteria, and may have evolved in response to the topography and expression of receptor epitopes at the host tissue surfaces.

Actinomyces↗

Classification and occurrence of clinically significant drug interactions with irinotecan and oxaliplatin in patients with metastatic colorectal cancer.

BACKGROUND: Pharmacokinetic and pharmacodynamic drug interactions with cytotoxic drugs may significantly influence the efficacy and toxicity of chemotherapy. OBJECTIVE: The purpose of this study was to identify drug interactions with irinotecan and oxaliplatin reported in the literature, to assess their clinical significance, and to examine the occurrence of these interactions in patients with metastatic colorectal cancer treated with either irinotecan or oxaliplatin or both. METHODS: To obtain data on drug-drug interactions with irinotecan and oxaliplatin, a literature search of PubMed and EMBASE was conducted using the search terms irinotecan, oxaliplatin, and interactions (English-language studies only published between 1980 and August 2004). The interactions found were subsequently classified for documentation evidence and severity of clinical effect, according to a 5-level classification system of a standard reference text, by a study panel of medical oncologists and clinical pharmacists. Comedication of patients who were treated with irinotecan or oxaliplatin, or both, was then examined to determine the occurrence of clinically significant interactions. RESULTS: Ninety-eight patients (50 women, 48 men;mean age, 60 years) were included in the study. Seventeen interactions with irinotecan were found in the literature, and 11 were classified as clinically significant. Only 1 nonspecific, clinically significant interaction was identified for oxaliplatin. Irinotecan-treated patients received a mean of 8 different comedications and oxaliplatin-treated patients received a mean of 6. Apart from antiemetic and antidiarrheal drugs that were prescribed for treatment-related toxicities, only 1 patient appeared to be exposed to a possible clinically significant interaction (between irinotecan and phenytoin). CONCLUSIONS: Eleven of the 17 interactions with irinotecan that were found in the literature were classified as clinically significant versus 1 clinically significant interaction with oxaliplatin. The occurrence of these interactions in the study patients with metastatic colorectal cancer was low. For medication surveillance purposes, however, the significant interactions should be considered in clinical practice.

Adolescent↗

EAU guidelines on diagnosis and treatment of upper urinary tract transitional cell carcinoma.

OBJECTIVES: On behalf of the European Association of Urology (EAU) guidelines for diagnosis, therapy and follow-up of upper urinary tract transitional cell carcinoma (UUTT) patients were established. Criteria for recommendations are based of level 2 only, as large randomised clinical trials have not been performed in this type of disease. METHOD: A systematic literature research using Medline Services was conducted. References were weighted by a panel of experts. RESULTS: TNM classification 2002 is recommended. Recommendations are developed for diagnosis, radical and conservative treatment and for local chemo-immunotherapy. Prognostic factors are defined. Recommendations for follow-up after different types of treatment are given.

Carcinoma, Transitional Cell↗

EAU guidelines on chronic pelvic pain.

OBJECTIVES: On behalf of the European Association of Urology (EAU) guidelines for diagnosis, therapy and follow-up of chronic pelvic pain patients were established. METHOD: Guidelines were compiled by a working group and based on current literature following a systematic review using MEDLINE. References were weighted by the panel of experts. RESULTS: The full text of the guidelines is available through the EAU Central Office and the EAU website (www.uroweb.org). This article is a short version of this text and summarises the main conclusions from the guidelines on management of chronic pelvic pain. CONCLUSION: A guidelines text is presented including chapters on prostate pain and bladder pain syndromes, urethral pain, scrotal pain, pelvic pain in gynaecological practice, role of the pelvic floor and pudendal nerve, general treatment of chronic pelvic pain and neuromodulation. These guidelines have been drawn up to provide support in the management of the large and difficult group of patients suffering from chronic pelvic pain.

Chronic Disease↗