bluuebunny/crossref_metadata_2025_split huggingface dataset:
Standardization and Quality Control of PCR Analyses
Authors: Burkardt Hans-Joachim 
Published: October 2004

Abstract
In the very beginning of polymerase chain reaction (PCR) tests entering the field of diagnosis of infectious agents, the introduction of this technology into routine diagnosis was hampered by its frequent tendency to create false-positive results because of contamination. This problem is now widely solved by the introduction of the uracil-N-glycosylase (UNG) anticontamination technology. However, care must still be taken to avoid other sources of producing false positive results. They might additionally derive from human error and/or insufficient PCR amplification and detection protocols. A special case lies in the fact that PCR also amplifies DNA from dead organisms rendering a result diagnostically correct as positive, but clinically as false-positive. In PCR, as in any other diagnostic test, the risk of creating a false-negative result also exists. In such a case, the most probable source besides human error, low target or poor amplification and detection protocols is an inhibition caused by interfering substances in a patient's sample. Strategies to recognize and overcome this issue are discussed in this article. Finally a few results from quality control studies on amplification technologies in the diagnosis of infectious agents are reviewed.
Histochemical and Immunocytochemical Approaches to the Study of Oxidative Stress
Authors: Raina Arun K. , Perry George , Nunomura Akihiko , Sayre Lawrence M. , Smith Mark A. 
Published: October 2004

Abstract
We review an array of newly developed in situ detection methods that can be used for the qualitative and semi-quantitative measurement of various indices related to oxidative stress. The importance of in situ methods over bulk analysis cannot be overstated when considering the structural and cellular complexity of tissue and the effects of diseases thereof. Indeed, in situ detection allows detection of specific cell types affected or specific localization such that a process affecting only a small fraction of the tissue or cells can be readily visualized. Consequently, a positive signal in situ indicates real levels that cannot be masked by unrelated or compensatory responses in adjacent cells, and corrections can be easily made for the modifications to long-lived proteins during physiological aging. In fact, the damage to extracellular matrix proteins of major vessels, provides a cumulative record of long-term oxidative insult. Yet the same properties that make vessels ideal markers for aging limits their sensitivity to detect disease-specific changes unless in situ techniques are used.
Sniffing out the Truth: Clinical Diagnosis Using the Electronic Nose
Authors: Pavlou A.K. , Turner A.P.F. 
Published: October 2004

AbstractRecently the use of smell in clinical diagnosis has been rediscovered due to major advances in odour sensing technology and artificial intelligence (AI). It was well known in the past that a number of infectious or metabolic diseases could liberate specific odours characteristic of the disease stage. Later chromatographic techniques identified an enormous number of volatiles in human clinical specimens that might serve as potential disease markers. “Artificial nose” technology has been employed in several areas of medical diagnosis, including rapid detection of tuberculosis (TB),Helicobacter pylori(HP) and urinary tract infections (UTI). Preliminary results have demonstrated the possibility of identifying and characterising microbial pathogens in clinical specimens. A hybrid intelligent model of four interdependent “tools”, odour generation “kits”, rapid volatile delivery and recovery systems, consistent low drift sensor performance and a hybrid intelligent system of parallel neural networks (NN) and expert systems, have been applied in gastric, pulmonary and urine diagnosis. Initial clinical tests have shown that it may be possible in the near future to use electronic nose technology not only for the rapid detection of diseases such as peptic ulceration, UTI, and TB but also for the continuous dynamic monitoring of disease stages. Major advances in information and gas sensor technology could enhance the diagnostic power of future bio-electronic noses and facilitate global surveillance models of disease control and management.
Oncogenes and Thyroid Cancer
Authors: Vecchio Giancarlo , Santoro Massimo 
Published: October 2004

Abstract
Human thyroid tumors can be derived either from epithelial follicular cells or from parafollicular C-cells. Follicular cell-derived tumors represent a wide spectrum of lesions, ranging from benign adenomas through differentiated (follicular and papillary) and undifferentiated (anaplastic) carcinomas, thus providing a good model for finding a correlation between specific genetic lesions and histologic phenotype. Follicular adenomas and carcinomas show frequently the presence of mutations in one of the three ras genes. Papillary carcinomas show frequently a specific gene rearrangement which gives rise to the formation of several types of so-called RET/PTC chimeric genes. This lesions occur in almost 50% of papillary cancers and consist in the juxtaposition of the 3′ or tyrosine kinase domain of the RET gene (which codes for a receptor protein not normally expressed in follicular thyroid cells) with the 5′ domain of ubiquitously expressed genes, which provide the promoter and dimerization functions, necessary for the constitutive activation of RET/PTC proteins. Anaplastic carcinomas are frequently associated with mutations of the p53 tumor suppressor. Finally, point mutations of the RET gene are found in familial endocrine syndromes (FMTC; MEN2A and MEN2B), a common feature of which is the medullary thyroid carcinoma, a malignant tumor derived from parafollicular C-cells.
Paraneoplastic Syndromes of the Nervous System
Authors: Posner Jerome B. , Dalmau Josep O. 
Published: October 2004

Abstract
Paraneoplastic syndromes affecting the nervous system are unique among immune-mediated disorders in that the trigger of the immune response is known: tumor expression of proteins normally restricted to neurons (or other immunoprivileged sites, such as testis) but ectopically expressed in some cancers results in an immunological response characterized by high titers of antibodies targeting the “onconeuronal” antigen. A T-cell response is also elicited in some paraneoplastic syndromes and may be the cause of neuronal destruction. In some instances genes that code for the antigens recognized by the autoantibodies have been identified, cloned and sequenced. Some of the proteins so identified are RNA binding proteins but their specific function has not been identified. In some individuals with cancer but no paraneoplastic syndrome, low titers of antibody can be identified in the serum. Low titers of antibody are associated with a better prognosis of the cancer. Experimental animals immunized against a paraneoplastic antigen are partially protected against tumors that express that antigen.
Genetic Modifying Factors in β-Thalassemia
Authors: Cao Antonio , Moi Paolo 
Published: October 2004

Abstract
The β-thalassemia is probably the most extensively studied genetic disease. Essentially any molecular defect that has been first described in association with the globin genes has been later implicated as a molecular determinant of newly discovered genes. Accordingly, the thalassemias have always represented a model genetic disease, especially in relation to the development of programs for population screening, genetic counseling and prenatal diagnosis. Here we will review the present knowledge on the genetics of thalassemia and of the relevant modifying factors. Major categories of the carrier state, the genotypes, the clinical phenotypes and the correlation between genotype and phenotype will be discussed.
The Genetics of Multiple Sclerosis
Authors: Compston Alastair 
Published: October 2004

Abstract
Classical genetic studies involving the analysis of pedigrees and recurrence risk within families have defined the extent to which genetic factors contribute to the aetiology of multiple sclerosis. Limited progress has been made in identifying the number and topography of genetic loci contributing to susceptibility through molecular investigation either of candidate genes or the whole genome using microsatellite and single nucleotide polymorphisms.
Ribozyme Gene Therapy for Autosomal Dominant Retinal Disease
Authors: Hauswirth William W. , LaVail Matthew M. , Flannery John G. , Lewin Alfred S. 
Published: October 2004

Abstract
Gene delivery to cells of the retina, particularly to photoreceptor cells, has broad potential both for answering basic questions of retinal biology and for more applied therapeutic purposes. The use of ribozymes as therapy for autosomal dominant retinal diseases is a promising technique, and the theoretical and practical basis for their use is discussed. The process involves designing and testing ribozymes first in vitro and then in animal models of retinal disease. Viral vectors based on the nonpathogenic human adeno-associated virus, when coupled with the strong, rod photoreceptor specific opsin promoter, offer an efficient and nontoxic way to deliver and express ribozymes in photoreceptor cells for long time periods of time. Effective ribozyme-mediated therapy also demands careful in vitro analysis of a ribozyme's ability to efficiently and specifically distinguish between mutant and wild type RNAs. Finally, effective demonstration of therapy in an animal model requires careful analysis of any rescue effect in the retina using multiple criteria, including biochemical, structural and physiological assays. For this purpose, ribozyme therapy in a transgenic rat model of retinitis pigmentosa containing a dominant rod opsin mutation (proline-to-histidine change at position 23) is discussed in detail.
Oxidized Lipoproteins and Endothelium
Authors: Pirillo Angela , Zhu Weimin , Norata Giuseppe D. , Zanelli Tiziano , Barberi Laura , Roma Paola , Catapano Alberico L. 
Published: October 2004

Abstract
Endothelium is an early target of pro-atherosclerotic events, which may result in functional and morphological perturbations. Oxidized low density lipoproteins, an atherogenic factor with strong cytotoxicity, may potentially contribute to altered endothelial function through the activation of a stress response, which would rescue cells to full vitality, or, conversely, by leading to cell death. Evidence is presented here for the ability of chemically oxidized low density lipoproteins to induce the synthesis of the inducible form of heat shock protein 70 in cultured human endothelial cells, and for the association of epitopes of these modified lipoproteins with apoptotic endothelial cells in aortic sections from hypercholesterolemic rabbits.
Experiences with External Quality Assessment (EQA) in Molecular Diagnostics in Clinical Laboratories in Germany
Authors: Neumaier Michael , Braun Andreas , Gessner Reinhard , Funke Harald 
Published: October 2004

Abstract
The German Societies for Clinical Chemistry (DGKC) and Laboratory Medicine (DGLM) have established an official working group on molecular diagnostics in the field of laboratory medicine. The group's objectives are to support the establishment of molecular biology methods for the use in diagnostics in German clinical laboratories. Towards this end, we have defined specific aims, which are 1) the implementation and extension of external quality assessment (EQA) schemes and methodological exercises offered to clinical diagnostic laboratories, 2) the establishment of a proficiency network and data base within the societies, 3) the implementation of an educational program in molecular diagnostic procedures for clinical chemists and laboratory physicians through the organisation of symposia and workshops and 4) the cooperation with other DGKC/DGLM working groups on shared aspects of laboratory analysis, e.g. preanalytics. The focus of this presentation is to introduce some of these goals in more detail with particular emphasis on the first two program aspects and to discuss experiences with these activities.
Unravelling Genetic Data by Arrayed Primer Extension
Authors: Tõnisson Neeme , Kurg Ants , Kaasik Krista , Lõhmussaar Elin , Metspalu Andres 
Published: October 2004

AbstractWe have developed a method for arrayed primer extension (APEX) on an oligonucleotide microchip together with the 4-color fluoresence imaging equipment and supporting software, that allows analysis of the DNA sequence and changes in it. Mutation analysis of BRCA1 gene and single nucleotide polymorphism (SNP) chip for genotyping were used as a model system. Chip surface chemistry, template preparation and APEX reaction conditions were optimised and the assay is ready to be implemented in variety of DNA analysis from SNP testing to DNA resequencing.
Laboratory Diagnosis of Patients with Acute Chest Pain
Authors: Penttilä Ilkka , Penttilä Karri , Rantanen Tapio 
Published: October 2004

Abstract
The enzyme activities of creatine kinase (CK), its isoenzyme MB (CK-MB) and of lactate dehydrogenase isoenzyme 1 (LD-1) have been used for years in diagnosing patients with chest pain in order to differentiate patients with acute myocardial infarction (AMI) from non-AMI patients. These methods are easy to perform as automated analyses, but they are not specific for cardiac muscle damage. During the early 90's the situation changed. First creatine kinase MB mass (CK-MB mass) replaced the measurement of CK-MB activity. Subsequently cardiac-specific proteins troponin T (cTnT) and troponin I (cTnI) appeared on the scene, displacing LD-1 analysis. However, troponin concentrations in blood increase only from four to six hours after onset of chest pain. Therefore a rapid marker such as myoglobin, fatty acid binding protein or glycogen phosphorylase BB could be used in early diagnosis of AMI. On the other hand, CK-MB isoforms alone may also be useful in rapid diagnosis of cardiac muscle damage. Myoglobin, CK-MB mass, cTnT and cTnI are nowadays widely used in diagnosing patients with acute chest pain. Myoglobin is not cardiac-specific and therefore requires supplementation with some other analyses such as troponins to support the myoglobin value. Troponins are very highly cardiac-specific. Only the sera of some patients with severe renal failure, which requires hemodialysis, have elevated cTnT and /or cTnI without there being any evidence of cardiac damage. On the other hand, the latest studies have shown that elevated troponin levels in sera of hemodialysis patients point to an increased risk of future cardiac events in a similar manner to the elevated troponin values in sera of patients with unstable angina pectoris. In addition, the bedside tests for cTnT and cTnI alone or together with myoglobin and CK-MB mass can be used instead of quantitative analyses in the diagnosis of patients with chest pain. These rapid tests are easy to perform and they do not require expensive instrumentation. For routine clinical laboratory practice we suggest that in diagnosis of patients with chest pain, myoglobin and CK-MB mass measurements should be performed whenever they are requested (24 h/day) and cTnT or cTnI on admission to the hospital and then 4–6 and 12 hours later.
Methods for the Determination of Plasma Total Homocysteine: a Review
Authors: Amores-Sánchez Maria Isabel , Medina Miguel Ángel 
Published: October 2004

Abstract
Total homocysteine is the sum of all homocysteine species present in plasma. This parameter is valuable for the diagnosis and follow up of cobalamine or folate deficiencies, and it has been accepted as an independent risk factor for premature cardiovascular disease. These reasons justify the introduction of total homocysteine assays in the routine clinical laboratory. In the present review, we discuss the procedures for sample collection, processing and storage, and review the methodologies for measuring total homocysteine. We compare their feasibility as routine methods in the clinical laboratory.
Serum Protein 90K/Mac-2BP Is an Independent Predictor of Disease Severity during Hepatitis C Virus Infection
Authors: Kittl Eva M. , Hofmann Jörg , Hartmann Gerold , Sebesta Christian , Beer Franz , Bauer Kurt , Huber Klaus R. 
Published: October 2004

Abstract
The serum protein designated 90K/Mac-2BP has been found at elevated concentrations in the sera of patients with various types of cancer and viral infections. The importance of the 90K/Mac-2BP serum concentrations in predicting the response towards interferon-α treatment for hepatitis C virus (HCV) infection prompted us to utilize a new ELISA for soluble human 90K/Mac-2BP to monitor the serum concentrations of this protein in our HCV-positive patients. Seventy HCV-PCR and anti-HCV antibody positive patients were analyzed for their serum levels of aspartate aminotransferase, alanine aminotransferase, γ-glutamyltransferase, cholinesterase, HCV-viral load, viral subtypes, and 90K/Mac-2BP. On correlation of age and 90K/Mac-2BP levels, we found an apparent correlation that was proved rather to be a strong dependence of 90K/Mac-2BP concentrations on disease severity/duration, which increases with age. Multiple correlation analysis demonstrated the independent nature of 90K/Mac-2BP concentrations, underscoring the potential high utility of this new marker. Our data corroborate the potential of the scavenger receptor family protein 90K/Mac-2BP as an independent predictor of disease severity during HCV infection.
Biochemical and Hematological Changes in Low-Level Aluminum Intoxication
Authors: González-Revaldería Joaquín , Casares Miguel , Paula Marta de , Pascual Tomás , Giner Vicente , Miravalles Elena 
Published: October 2004

Abstract
The aim of this study was to investigate the biochemical and hematological changes in patients on routine hemodialysis treatment when they were accidentally exposed to moderately high serum aluminum concentrations during a period of time of less than four months. We studied the changes in biochemical and hematological measurements in 33 patients on dialysis in our hospital before and during the exposure to about 0.85 μmol/l of aluminum in dialysis water due to a malfunction of the reverse osmosis system of water purification. Patients showed a decrease in the hemoglobin concentration from 115 ± 12.4 g/l to 108 ± 12.2 g/l (p=0.026) and in the mean corpuscular hemoglobin concentration from 5.15 ± 0.22 to 5.02 ± 0.30 mmol/l (p=0.014). Ferritin was decreased from 243 ± 192 μg/l to 196 ± 163 μg/l (p= 0.047) and transferrin saturation from 0.20 ± 0.06 to 0.15 ± 0.07 (p= 0.004). Biochemical measurements related to calcium-phosphate metabolism did not change. Otherwise, all patients showed an increase in serum aluminum from 0.56 ± 0.44 to 1.63 ± 0.52 μmol/l (p<0.001). No differences were detected in serum aluminum between patients receiving and not receiving oral aluminum salts. Even moderately high aluminum concentrations maintained during a short period of time could produce significant hematological alterations and a depletion of body iron stores before clinical manifestations were evident.
On Accuracy and Precision of a HPLC Method for Measurement of Urine Porphyrin Concentrations
Authors: Zuijderhoudt Floris M.J. , Koehorst Stephan G.A. , Kluitenberg Willem E. , Bok Jenneke Dorresteijn-de 
Published: October 2004

Abstract
We studied the accuracy and precision of a HPLC method for determination of porphyrins in urine. A commercial standard solution appeared to contain less porphyrins than indicated by the manufacturer, since calibration resulted in lower concentrations of uroporphyrin and coproporphyrin: 16% and 8%, respectively. Coefficients of variation for the measurement of uro-, hepta-, copro I and copro III porphyrins in samples of patients with and without porphyria were often much less than 15%. Comparison of measurements with and without calibrated standards revealed differences for uroporphyrin and coproporphyrin of 27% and 5%, respectively. Recovery of added uroporphyrin and coproporphyrin was 99%. The main cause of the variability in test results was apparently the improperly calibrated standard solutions. The precision of porphyrin measurements was not influenced by the type of porphyria.
Point-of-Care Testing
Authors: Jansen Rob T. P. 
Published: October 2004

Abstract
In the recent issue of CCLM a paper has been published
on the view of the German Working Group on Point-of-Care Testing (POCT) (1). The issue of POCT is extremely
important and rightly the authors stress the responsibility
of the head of the laboratory.
However, they omit to refer to two important documents
relating to POCT from the European Communities
Confederation of Clinical Chemistry (EC4): one on
the essential criteria for quality systems of medical laboratories
(2) and another on the additional essential criteria
for quality systems of medical laboratories (3), the
latter addressing in particular POCT. Both of these documents
strongly influence new ISO documents on
quality management in medical laboratories. The section
of the German Working Group's paper on organizational
prerequisites for the establishment of POCT in
a hospital could particularly benefit from these references.
Physiological and Morphological Characterization of Dentate Granule Cells in the p35 Knock-Out Mouse Hippocampus: Evidence for an Epileptic Circuit
Authors: Patel Leena S. , Wenzel H. Jürgen , Schwartzkroin Philip A. 
Published: October 2004

There is a high correlation between pediatric epilepsies and neuronal migration disorders. What remains unclear is whether there are intrinsic features of the individual dysplastic cells that give rise to heightened seizure susceptibility, or whether these dysplastic cells contribute to seizure activity by establishing abnormal circuits that alter the balance of inhibition and excitation. Mice lacking a functionalp35gene provide an ideal model in which to address these questions, because these knock-out animals not only exhibit aberrant neuronal migration but also demonstrate spontaneous seizures.Extracellular field recordings from hippocampal slices, characterizing the input-output relationship in the dentate, revealed little difference between wild-type and knock-out mice under both normal and elevated extracellular potassium conditions. However, in the presence of the GABAAantagonist bicuculline, p35 knock-out slices, but not wild-type slices, exhibited prolonged depolarizations in response to stimulation of the perforant path. There were no significant differences in the intrinsic properties of dentate granule cells (i.e., input resistance, time constant, action potential generation) from wild-type versus knock-out mice. However, antidromic activation (mossy fiber stimulation) evoked an excitatory synaptic response in over 65% of granule cells from p35 knock-out slices that was never observed in wild-type slices. Ultrastructural analyses identified morphological substrates for this aberrant excitation: recurrent axon collaterals, abnormal basal dendrites, and mossy fiber terminals forming synapses onto the spines of neighboring granule cells. These studies suggest that granule cells in p35 knock-out mice contribute to seizure activity by forming an abnormal excitatory feedback circuit.