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PubMed1989

A study of the extracellular matrix protein as the migration pathway of neural crest cells in the gut: analysis in human embryos with special reference to the pathogenesis of Hirschsprung's disease.

Immunocytochemical studies on the human embryo were made using antineuronal cell antibody and a panel of anti-extracellular matrix protein antibodies such as fibronectin, laminine, collagen type IV, and hyaluronic acid. All the enteric ganglia are shown to be from a single, vagal neural crest source, although the recent dual gradient migration theory of neural-crest-derived cells in the gut can be challenged. Neural-crest-derived cells first appear in the mesenchyme of the developing esophagus at 4 weeks, and then migrate down along the gut in a craniocaudal direction. The observed distribution of fibronectin and hyaluronic acid indicates the presence of these matrices providing a migration pathway for neural-crest-derived cells in the developing gut. The appearance of neural-crest-derived cells in the gut is always preceded by the appearance of these matrices. On the other hand, substrate or laminine and collagen type IV appears to promote outgrowth of neurites from settled neural-crest-derived cells and their maturation. The distribution of these matrices within the pathway seems consistent with their role in navigating the neural-crest-derived cells toward their final destination. Enteric neurogenesis is dependent on these matrices, and their alteration in early embryonal stage may be a significant factor in the pathogenesis of Hirschsprung's disease.

Cell Movement↗

PubMed1995

Cardiac rehabilitation as secondary prevention. Agency for Health Care Policy and Research and National Heart, Lung, and Blood Institute.

This Quick Reference Guide for Clinicians highlights the conclusions and recommendations from Cardiac Rehabilitation, Clinical Practice Guideline No. 17, which was formulated by a panel representing the major health care disciplines involved in cardiac rehabilitation. The conclusions and recommendations were derived from an extensive and critical review of the scientific literature pertaining to cardiac rehabilitation, as well as from the expert opinion of the panel. This guide addresses the role of cardiac rehabilitation and the potential benefits to be derived in the comprehensive care of the 13.5 million patients with heart disease in the United States, as well as the 4.7 million patients with heart failure and the several thousand patients undergoing heart transplantation. This Quick Reference Guide for Clinicians highlights the major effects of multifactorial cardiac rehabilitation services: medical evaluation; prescribed exercise; cardiac risk factor modification; and education, counseling, and behavioral interventions. The outcomes of and recommendations for cardiac rehabilitation services are categorized as to their effects on exercise tolerance, strength training, exercise habits, symptoms, smoking, lipids, body weight, blood pressure, psychological well-being, social adjustment and functioning, return to work, morbidity and safety issues, mortality and safety issues, and pathophysiologic measures. Patients with heart failure and after cardiac transplantation, as well as elderly patients, are specifically addressed. Alternate approaches to the delivery of cardiac rehabilitation services are presented.

Aged↗

PubMed2004

External quality assessment for the detection of blood-borne viruses in plasma by nucleic acid amplification technology: the first human immunodeficiency virus and hepatitis B virus studies (HIV EQA/1 and HBV EQA/1) and the fifth hepatitis C virus study (HCV EQA/5).

BACKGROUND AND OBJECTIVES: This External Quality Assessment (EQA) study was aimed at assessing the proficiency of blood centres and blood product manufacturers in detecting, by nucleic acid amplification technology (NAT), the possible contamination of plasma with hepatitis C virus (HCV), human immunodeficiency virus (HIV) and hepatitis B virus (HBV). MATERIALS AND METHODS: Three independent panels, one for each virus, were prepared at the Istituto Superiore di Sanità (ISS) by diluting the respective reference preparations. NAT methods used by the EQA participants included polymerase chain reaction (PCR) assays by Roche, transcription-mediated amplification (TMA) assays by Chiron and in-house PCR assays. RESULTS: Forty-three of the 45 participants (95.6%) in the HCV EQA/5 who used a validated method were consistently able to detect a nominal concentration of 100 IU/ml for all six major genotypes. In the case of the HIV EQA/1, all 35 participants detected the samples containing 1000 IU/ml HIV, while five (14.3%) did not identify the samples containing 100 IU/ml HIV. With respect to the HBV EQA/1, all 16 participants correctly identified the positive samples containing either 1000 IU/ml or 100 IU/ml HBV. No false-positive results were observed with any of the three panels. CONCLUSIONS: The HCV EQA/5 showed an improved proficiency of laboratories as compared with the HCV EQA/4. In fact, HCV genotypes 1, 2, 3 and 5 were correctly identified in 100% of the assays and genotypes 4 and 6 in 97.8% of the assays. While most of the participants in the HIV EQA/1 showed a good level of proficiency, an excellent performance was shown by all participants in the HBV EQA/1.

False Positive Reactions↗

PubMed2001

The Otsego-Schoharie healthy heart program: prevention of cardiovascular disease in the rural US.

OBJECTIVES: To describe a rural, hospital-based public health intervention program and to evaluate its effectiveness in cardiovascular disease (CVD) risk reduction using cross-sectional studies and a panel study. METHODS: A rural population of 158,000 located in New York state comprised the intervention population. A similar but separate population was used for reference. A multifaceted, multimedia 5-year program provided health promotion and education initiatives to increase physical activity, decrease smoking, improve nutrition, and identify hypercholesterolemia and hypertension. To evaluate the effectiveness of the intervention, surveys were conducted at baseline in 1989 (cross-sectional) and at follow-up in 1994-95 (cross-sectional and panel). For cross-sectional studies, a random sample of adults was obtained using a three-stage cluster design. Self-reported and objective risk factor measurements were obtained. Comparison of pre- to post- changes in intervention versus reference populations was done using 2 x 2 randomized block ANOVA, 2 x 2 mixed ANOVA. and extension of the McNemar test. RESULTS: Smoking prevalence declined (from 27.9% to 17.6%) in the intervention population. Significant adverse trends were observed for high-density lipoprotein cholesterol and triglycerides. Systolic blood pressure was reduced while diastolic blood pressure remained stable. Body mass index increased significantly in both populations. CONCLUSIONS: This rural. 5-year CVD community intervention program decreased smoking. The risk reduction may be attributable to tailoring of a multifaceted approach (multiple risk factors, multiple messages, and multiple population subgroups) to a target rural population. The study period was too short to identify changes in CVD morbidity and mortality.

Adult↗

PubMed1997

Illness awareness in cancer patients: a conceptual framework and a preliminary classification hypothesis.

The study describes the initial phases of research aimed at developing a methodology for assessing awareness in cancer patients. A first sample of cancer patients (n = 36) was interviewed about their knowledge of the diagnosis and their perception of treatment goals and outcomes. Thirteen domains which refer both to cognitive and emotional areas were identified, and considered as content valid by a panel of six experts. A second sample of patients (n = 54) participated in a semi-structured interview developed to explore awareness by means of the domains identified. Seven patterns of awareness were identified, ranging from 'completely aware patient' to 'completely unaware patient'. Twenty of the 54 patients (37.0%) were completely aware, 19 (35.2%) were partially aware with defence mechanisms and 15 (27.8%) were not aware of their diagnosis. Patients from the National Cancer Institute were more frequently aware (54.3%) compared with the patients interviewed in the community hospitals (5.3%) (p < 0.001). A computerized content analysis allowed the identification of two main groups of patients on the basis of the content of the recorded interviews. This independent classification agreed with the classification of the patients performed by the psychologists, suggesting the validity of the procedure of awareness evaluation proposed in this study.

Adaptation, Psychological↗

PubMed1994

Variable-region subgroup distribution among lambda-type immunoglobulins in normal human serum.

The distribution of the major VL subgroups (V lambda I, V lambda II, V lambda III, V lambda IV, V lambda VI, and V lambda VIII) among lambda-type immunoglobulins (Igs) in normal serum was determined by a sandwich enzyme-linked immunosorbent assay (ELISA) using a panel of murine anti-human V lambda-subgroup-specific monoclonal antibodies (MoAbs) and appropriate reference standard proteins. The mean concentration of lambda I, lambda II, lambda III, lambda IV, lambda VI, and lambda VIII Igs in serum specimens obtained from 23 adults was 2158, 162, 1958, 264, 225, and 169 micrograms/mL and represented 44, 3, 40, 5, 5, and 3% of the total Ig lambda population, respectively. The low percentage of lambda II Igs in normal serum was in marked contrast to the approximately 40% incidence of this V lambda subgroup found among lambda-type Bence Jones proteins and monoclonal serum Igs obtained from patients with multiple myeloma and AL amyloidosis, or approximately 60% in Waldenström's macroglobulinemia. The non-random expression of the V lambda II subgroup in these diseases implies a relationship between V lambda-gene usage and plasma cell, as well as certain types of lymphocytic dyscrasias.

Adult↗

PubMed2001

A molecular clock dates the common ancestor of European-type porcine reproductive and respiratory syndrome virus at more than 10 years before the emergence of disease.

The disease caused by porcine reproductive and respiratory syndrome virus (PRRSV) emerged independently and almost simultaneously in Europe (1990) and North America (1987). The original reservoir of the virus and the date it entered the pig populations is not known. In this study, we demonstrate an accurate molecular clock for the European PRRSV ORF 3 gene, place the root in the genealogy, estimate the rate of nucleotide substitution, and date the most recent common viral ancestor of the data set to 1979; more than 10 years before the onset of the European epidemic. Based on these findings, we conclude that PRRSV virus most likely entered the pig population some time before the epidemic emergence of the virus, and hence, that emergence of European-type PRRSV is not the result of a recent species transmission event. Together, our results show that ORF3 sequencing is a valuable epidemiologic tool for examining the emergence and spread of PRRSV in Europe. As such, the panel of well-characterized and highly divergent ORF3 sequences described in this study provides a reference point for future molecular epidemiologic studies.

Animals↗

PubMed1994

Evaluation of an automated system for identification of anaerobic bacteria.

A fully automated computer-assisted system (ATB system, bioMérieux, France) which uses disposable microenzymatic panels was evaluated for its ability to identify 215 strains of anaerobic bacteria (clinical isolates and reference strains). All strains were examined using conventional identification protocols and by gas chromatographic analysis of short-chain fatty acids. Automated reading of Rapid ID32A test kits (bioMérieux, France) by the ATB system gave correct identification for 195 strains (90.7%): 92.25% of gram-negative anaerobes (116 strains) and 89% of gram-positive anaerobes (99 strains) were correctly identified. Twelve strains (5.6%) were incorrectly identified and 8 strains (3.7%) were not identified by the system. For some strains in the Bacteroides fragilis group, for Clostridium difficile and for the Fusobacterium genus, additional tests suggested by the ATB software were necessary to reach a final identification at the species or genus level. On the basis of the high incidence of correct identifications and the comparison of these results with those obtained previously using other commercially available kits, the ATB system was found to be a reliable method for identification of anaerobic bacteria in clinical laboratories.

Bacteria, Anaerobic↗

PubMed2005

The development of a quality assurance programme for HPV testing within the UK NHS cervical screening LBC/HPV studies.

BACKGROUND: Cervical screening by cytology is effective but lacks sensitivity. The addition of human papillomavirus (HPV) testing can improve the effectiveness of screening for early identification of cervical disease. As HPV testing represents a new technology, a quality assurance (QA) programme is necessary to confirm the accuracy of results. OBJECTIVE: Our main objective was to design a QA programme for use in the English NHS liquid-based cytology (LBC) and HPV Cervical Screening Pilot Study. Our second objective was to use the knowledge gained to design a QA scheme for future general use within cervical screening and HPV testing programmes. STUDY DESIGN: Four elements were included in the programme: provision of clinical samples of known HPV status for internal quality control (IQC), distribution of panels of unknown samples for external quality assessment (EQA), resubmission of aliquots of samples to the reference laboratory for repeat testing and resubmission to reference laboratory to check for transport problems. Three sites took part in the QA programme using PreservCyt medium and ThinPrep for LBC preparation. The assay used at test sites was HPV hybrid capture (hc2) while the quality assurance laboratory used a combination of hc2, in-house HPV polymerase chain reaction (PCR) tests and HPV linear array (LA). RESULTS: Four negative, three low positive and 11 positive pools were used in 22 distributions of IQC samples. Seven distributions each of five 'unknown' EQA samples were sent out. Over 400 samples underwent repeat testing. Discrepant samples were further assessed to provide an explanation. Inter- and intra-laboratory consistency was high as measured by Kappa statistics and 96% agreement for EQA samples was obtained. CONCLUSIONS: The validity of the QA programme was established and reproducibility in different lab settings was reassuring. These results support the use of hc2 as a potential screening test in diagnostic laboratories. The need for robust quality assurance of HPV testing in cervical screening programmes was confirmed and lessons learnt from this pilot study will be incorporated in future schemes.

DNA, Viral↗

PubMed1983

How necessary are specific IgE antibody tests in allergy diagnosis?

In a 12-month study 301 patients referred to hospital consultants with putative allergic symptoms were tested for specific IgE antibodies to a panel of allergens and for total serum IgE levels. Examination of the data in relation to clinical information and the results of skin prick tests showed that the specific IgE antibody test has a limited role in the investigation of such patients.

Adolescent↗

PubMed1997

The anti-erythrocyte autoimmune response of NZB mice. Identification of two distinct autoantigens.

With age, New Zealand black (NZB) mice spontaneously develop anti-mouse red blood cell (RBC) autoantibodies resulting in the development of autoimmune haemolytic anemia (AIHA). Previously, we characterized a panel of monoclonal autoantibodies derived from unimmunized, adult NZB mice. One of these antibodies (G8) was shown to be pathogenic, inducing AIHA in a non-autoimmune-prone mouse strain (BALB/c). Using G8, and two other antibodies from our panel, we have characterized two distinct autoantigens on the surface of mouse RBCs. The autoantigen, historically referred to as antigen X (AgX), was found to be partially hidden on the surface of the mouse RBC because glycosidase treatment or mild digestion with proteinase K resulted in increased reactivity with autoantibodies. One of the monoclonal antibodies (3H5G1) was found to immunoprecipitate a 110,000 MW protein identified as the erythrocyte anion transporter (band 3) whereas the pathogenic antibody (G8) as well as a third monoclonal antibody (2E6m) were shown to immunoprecipitate a 60,000 MW protein that was not reactive with the anti-band 3 serum. Finally, we show that the autoantigen recognized by G8 is expressed on differentiated mouse erythroleukaemia (MEL) cells. The results suggest that a protein distinct from band 3 can serve as a target for AIHA in NZB mice.

Anemia, Hemolytic, Autoimmune↗

PubMed1999

Biomarkers for establishing a tolerable upper intake level for vitamin C.

Dietary reference intakes (DRIs) for vitamin C for healthy U.S. populations are currently being formulated by the Panel on Dietary Antioxidants and Related Compounds of the Food and Nutrition Board of the Institute of Medicine. A major task of the Panel is to analyze the evidence of adverse effects of high-dose vitamin C intakes to derive, if appropriate, a Tolerable Upper Intake Level (UL) for vitamin C. The present report details current and past research examining potential adverse effects of supplemental vitamin C. The available data indicate that very high intakes of vitamin C (2-4 g/day) are well tolerated biologically in healthy mammalian systems. Currently, strong scientific evidence to define and defend a UL for vitamin C is not available.

Adult↗

PubMed1999

Reactivity of anti-PSA monoclonal antibodies with recombinant human kallikrein-2.

Seventy-nine monoclonal antibodies submitted to the ISOBM TD-3 PSA Workshop were tested for their reactivity with recombinant human kallikrein-2 (rhK2). A sandwich immunofluorometric assay using polyclonal anti-prostate-specific antigen (PSA) antiserum-coated plates was used to capture rhK2 and subsequently the test antibody. The response of each test antibody was compared with 3 reference antibodies (H50, H117 and 5E4) known to react with hK2. Nine antibodies from the workshop panel failed to react with purified PSA and rhK2 in this assay and were subsequently excluded. From the remaining panel of antibodies, 11/70 showed strong reactivity with rhK2, 9/70 showed weak reactivity with rhK2, while 50/70 antibodies did not react with rhK2 in this assay format. All antibodies binding to rhK2 recognized both free and complexed PSA.

Antibodies, Monoclonal↗

PubMed1999

Relationship between a self-reported health questionnaire and laboratory tests at initial office visits.

BACKGROUND: Dental patients routinely complete a medical questionnaire and have an oral interview during their initial visit, but may have undiagnosed systemic problems which can affect their dental treatment. METHODS: Thirty-nine consecutive patients referred for a periodontal evaluation completed a medical questionnaire and an oral interview. They were referred to a hospital laboratory for an urinalysis, complete blood count, and a standard blood chemistry panel. RESULTS: The self-reported medical history responses were compared with the laboratory data and several abnormalities were noted. Abnormal levels were found with cholesterol, (26/39 patients, 67%); triglycerides, (13/39, 33%); glucose, (6/39, 15%); eosinophils, (18/39, 46%); and monocytes, (10/39, 26%). Smokers (17/39, 44%) had a higher number of abnormal levels or percentages of cholesterol, triglycerides, basophils, lymphocytes, eosinophils, and monocytes. Gender differences were seen in elevated triglyceride levels, abnormal aspartate aminotransferase (AST) and alanine aminotransferase (ALT), and self-reported cardiovascular disease. CONCLUSIONS: This study demonstrated that many patients are unaware of their current medical status and a significant number had undiagnosed abnormalities.

Adult↗

PubMed2004

Triple nucleoside reverse transcriptase inhibitor therapy in children.

Much of the success attributed to HIV therapy in the last few years has resulted from improved ways of using existing drugs in combination therapy regimens. The availability of new, more potent drugs such as protease inhibitors and more accurate viral load tests to aid decisions to start or change treatment has also contributed to the success. Published recommendations for pediatric HIV therapy, generated by a panel of experts and specialists, are readily available and regularly updated. Preferred regimens of 'potent' therapy (referred to as highly active antiretroviral therapy, or HAART) currently consist of two nucleoside reverse transcriptase inhibitors (NRTIs) combined with either a non-nucleoside reverse transcriptase inhibitor (NNRTI) or a protease inhibitor. More intense four-drug regimens using an NNRTI or a second protease inhibitor as a fourth drug are being evaluated. Problems with HAART include: unpalatable drug formulations and adverse effects, coupled with lack of data on the pharmacokinetics, efficacy, and safety of various drug combinations. Adherence is a major factor influencing the efficacy and outcome of antiretroviral therapy. Many children cannot adhere to complex multidrug regimens, which cause virologic failure, despite excellent CD4+ cell count responses. This means a rapid progression through the limited number of treatment regimens available. Simpler regimens such as those containing three NRTIs have been proposed as a method of treatment that will allow suppression of the virus, yet circumvent many of the problems previously mentioned. An additional benefit would be the preservation of antiretroviral drugs from other classes for future treatment options if required. The major advantages of triple NRTI regimens are the simplicity of the regimen, good tolerability, few drug-drug interactions, and infrequent adverse effects coupled with a low pill burden. However, abacavir hypersensitivity remains a major problem. Up to 3% of patients may develop an early idiosyncratic hypersensitivity reaction - fever, malaise, and mucositis with or without rash, which can progress to more advanced stages of shock and death. A major concern is the apparently inferior virologic control of triple NRTI therapy as demonstrated in the AIDS Clinical Trials Group A5095 study with zidovudine/lamivudine/abacavir (Trizivir) combination in adults. Such a combination should only be considered in special situations. Examples cited include informed patient choice based on anticipated poor adherence on other treatment regimens, or if concomitant drugs such as tuberculosis medication are prescribed. The low pill burden of triple NRTI regimens (especially if combined in a single pill such as Trizivir), offers hope that regimen simplification may still be possible in the future.

Antiretroviral Therapy, Highly Active↗

PubMed1987

Precipitins against microbes in mouldy hay in the sera of farmers with farmer's lung or chronic bronchitis and of healthy farmers.

The aim of this study was to determine which precipitins against four antigens in 2,440 farmers are associated with the occurrence of farmer's lung (FL). The antigen panel consisted of mycelial antigens of Micropolyspora faeni, Thermoactinomyces vulgaris, Aspergillus fumigatus and Aspergillus umbrosus. As reference groups we used healthy farmers and those with chronic bronchitis. For the occurrence of precipitins against the four antigens there was a statistically significant difference between farmers with FL and healthy farmers but not between farmers with chronic bronchitis and healthy farmers. In a stepwise logistic linear regression analysis, farmers with FL and chronic bronchitis were compared to healthy farmers with respect to precipitins to the four antigens. Precipitins against Thermoactinomyces vulgaris differentiated farmers with FL (p less than 0.05) but not farmers with chronic bronchitis from healthy farmers. In Finland the occurrence of FL seems to be associated mainly with precipitins against Thermoactinomyces vulgaris, not with precipitins against Micropolyspora faeni as in Great Britain, and not with precipitins of Aspergillus umbrosus, which occurred most frequently in the sera of Finnish farmers. This association is in accordance with the exposure to spores of airborne moulds in farmers' work environment, where spore concentrations of Thermoactinomyces vulgaris have been measured to be about six times higher than those of Micropolyspora faeni.

Antibodies, Bacterial↗

PubMed1997

Genomic structure and genetic mapping of the human neutral cysteine protease bleomycin hydrolase.

Bleomycin hydrolase (BH) is the only known eukaryotic enzyme that inactivates the widely used antineoplastic agent bleomycin (BLM) and is a primary candidate gene for protection against lethal BLM-induced pulmonary fibrosis and for BLM resistance in tumors. Human BH was found to exist as a single gene that was mapped to chromosome 17 using National Institute of General Medical Sciences human/rodent hybrid mapping panels and localized to 17q11.1-11.2 by linkage analysis using the Centre d'Etude du Polymorphisme Humain reference database. The human BH gene consisted of 11 exons ranging in size from 69-198 bp separated by introns of approximately 1 kb, reflecting the archetypal genomic structure of the cysteine protease family. A polymorphic site was identified in the eleventh exon at bp 1450 encoding either valine or isoleucine. These findings provide essential tools required to define the role of BH in BLM-induced pulmonary fibrosis and BLM resistance in tumors.

Animals↗

PubMed1997

Reliability of the histopathologic diagnosis of melanocytic dysplasia. The Dysplastic Nevus Panel.

OBJECTIVE: To determine the reliability of the histopathologic diagnosis of melanocytic dysplasia among diverse dermatopathologists who had no joint training, agreed to abide by predetermined criteria, and who were provided reference photomicrographs illustrative of the criteria. DESIGN, SETTING, AND PARTICIPANTS: A stratified random sample of 112 melanocytic tumors were chosen from the files of the pathology department of a large staff-model health maintenance organization. The original diagnoses included typical and dysplastic melanocytic nevi and melanoma. A single representative slide for each case was interpreted independently by each of the 5 panel dermatopathologists and 2 melanoma specialists. They had no prior knowledge of the original diagnosis or the diagnoses of the other panel members. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Interrater reliability was measured by intraclass and Pearson correlation coefficients. Each case was graded on a 5-point scale from no dysplasia to melanoma. RESULTS: The intraclass correlation among the panel members was 0.67 (95% confidence interval, 0.59-0.73). The Pearson correlations of each of the 5 panel dermatopathologists with the mean of the 2 melanoma specialists ranged from 0.67 to 0.84, and the correlations of the mean of the panel with the 2 melanoma specialists were 0.79 and 0.82; the mean reading of the melanoma specialists correlated 0.89 with the mean panel reading. Apparent protocol violations occurred in 6.5% of the readings. CONCLUSIONS: Agreement was substantial to excellent for the histopathologic diagnosis of 112 melanocytic tumors by dermatopathologists. Using predetermined criteria, melanocytic dysplasia can be reproducibly graded among diverse general dermatopathologists.

Case-Control Studies↗