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PubMed1991

The recombinant congenic strains--a novel genetic tool applied to the study of colon tumor development in the mouse.

The development of tumors in mice is under multigenic control, but, in spite of considerable efforts, the identification of the genes involved has so far been unsuccessful, because of the insufficient resolution power of the available genetic tools. Therefore, a novel genetic tool, the RC (Recombinant Congenic) strains system, was designed. In this system, a series of RC strains is produced from two inbred strains, a "background" strain and a "donor" strain. Each RC strain contains a different small subset of genes from the donor strain and the majority of genes from the background strain. As a consequence, the individual genes of the donor strain which are involved in the genetic control of a multigenic trait, become separated into different RC strains, where they can be identified and studied individually. One of the RC strains series which we produced is made from the parental strains BALB/cHeA (background strain) and STS/A (donor strain). We describe the genetic composition of this BALB/cHeA-C-STS/A (CcS/Dem) series and show, using 45 genetic autosomal markers, that it does not deviate from the theoretical expectation. We studied the usefulness of the CcS/Dem RC strains for analysis of the genetics of colon tumor development. The two parental strains, BALB/cHeA and STS/A, are relatively resistant and highly susceptible, respectively, to the induction of colon tumors by 1,2-dimethylhydrazine (DMH). The individual RC strains differ widely in colon tumor development after DMH treatment; some are highly susceptible, while others are very resistant. This indicates that a limited number of genes with a major effect are responsible for the high susceptibility of the STS strain. Consequently, these genes can be mapped by further analysis of the susceptible RC strains. The differences between the RC strains were not limited to the number of tumors, but the RC strains differed also in size of the tumors and the relative susceptibility of the two sexes. Our data indicate that the number of tumors and the size of tumors are not controlled by the same genes. The genetics of these different aspects of colon tumorigenesis can also be studied by the RC strains. The DMH-treated mice of the parental strains and the RC strains also developed anal tumors and haemangiomas in varying numbers. The strain distribution pattern (SDP) of susceptibility for each of the three types of tumors induced by DMH is different, indicating that development of these tumors is under control of different, largely non-overlapping, sets of genes.(ABSTRACT TRUNCATED AT 400 WORDS)

1,2-Dimethylhydrazine↗
PubMed1993

Chemical analyses as validators in smoking cessation programs.

This review addresses the use of chemical analyses to validate the smoking status of a participant in a smoking cessation program. Pharmacokinetic and chemical validation literature leads to the conclusion that chemical analyses are most reliably used to confirm abstinence from smoking rather than as quantitative measures of nicotine intake or smoking activity. Analytical methodologies used in smoking validation studies are reviewed with their advantages and disadvantages. Close collaboration of behavioral scientists and analytical chemists is encouraged to validate the smoking status of participants in a smoking cessation program.

Biomarkers↗
PubMed1993

Monitoring of serum proteinase--antiproteinase balance and systemic inflammatory response in prognostic evaluation of acute pancreatitis. Results of a prospective multicenter study.

With the aim of studying the clinical usefulness and applicability of circulating levels of protease inhibitors, complement factors, acute phase reactants, and leukocytic enzymes in the prognostic evaluation of acute pancreatitis (AP), the present prospective multicenter study has been carried out. A total of 182 patients with AP have been included, to whom an exhaustive evolutive protocol has been applied from the time of their hospital admission (2-12 hr from the onset of the disease) until the 15th day of evolution in order to clearly define them. The severe episodes exhibit a greater consumption of alpha 2-macroglobulin, and C3 and C4 complement factors, as well as a greater increase of alpha 1-protease inhibitor, C-reactive protein and polymorphonuclear elastase than mild events, with regards to the underlying pathophysiological condition. The determination of the plasma levels of leukocytic elastase in the first hours of evolution allows a prediction of the severity of the acute pancreatitis event with a high reliability (predictive values that become higher than 90%). The clinical value of the remaining parameters analyzed, in this aspect, is less, being applicable to the monitoring of the disease.

Acute Disease↗
PubMed1996

Maternal serum creatine kinase does not predict tubal pregnancy.

PURPOSE: Our purpose was to validate prospectively the predictive value of maternal serum creatine kinase in the evaluation of ectopic pregnancy. METHODS: Fifty-one consecutive pregnant first-trimester patients who presented for suspected abnormal pregnancy were enrolled. Maternal serum samples were obtained and assayed for creatine kinase. Patients were subsequently evaluated for abnormal pregnancy by serial quantitative hCG levels, transvaginal ultrasonography, and surgery when appropriate. A receiver operating characteristic (ROC) curve was generated comparing intrauterine to extrauterine (ectopic) pregnancy. RESULTS: Of 51 patients, 18 had an ectopic pregnancy, 16 had a spontaneous abortion, and 17 had an ongoing intrauterine pregnancy. The ROC curve revealed that maternal serum creatine kinase had no ability to predict ectopic pregnancy. CONCLUSIONS: Maternal serum creatine kinase is not a reliable predictor of tubal pregnancy.

Biomarkers↗
PubMed2000

Determination of CKMB activity and protein concentration and their application in the diagnosis of AMI.

The activity and protein concentration of CKMB in 19 patients with AMI, 17 non-AMI patients and 26 normal persons. It was found that both peak times in patients with AMI and non-AMI patients were similar but the peak values were different. At peak values the F value of CKMB (5.3) was much lower than that of CKMB protein concentration (50.1). We are led to conclude that the measurement of CKMB protein level can identify AMI much earlier than that of CKMB activity.

Aged↗
PubMed1989

Establishment and characterization of an immature epithelial cell line (ENU-T-1) derived from a rat nephroblastoma.

A new cell line designated ENU-T-1 has been established from a xenotransplanted experimental rat nephroblastoma. The cultured cells are spindle-shaped or polygonal and are arranged in a wavy fashion morphologically similar to cultured embryonal renal epithelial cells. The cells exhibit a number of epithelial characteristics. Enzyme histochemistry gives positive reactions for gamma-glutamyltranspeptidase and alkaline phosphatase, both of which are present in renal tubular epithelial cells. Immunofluorescence studies show positive reactions for vimentin and cytokeratin. When inoculated into athymic nude mice, the cultured cells form tumors composed of sheets of epithelial cells with focal tubular formation. This cell line may be of value in studying differentiation of nephroblastoma, and possibly normal nephrogenesis.

Animals↗
PubMedDate not supplied

Markers of increased thrombin generation.

Blood clotting activation causes an increased thrombin generation. The direct measurement of plasma thrombin is not feasible due to the absence of reliable methods. Thus, only indirect approaches are possible. Different markers of thrombin generation have been proposed in the past years. Some methods are nowadays of historical interest. Among various methods reported the 'gold standard' is fibrinopeptide A assay, while thrombin-antithrombin complexes assay needs further validation to be employed as a reliable index of increased thrombin generation, and more recent methods (such as those for F1+2 fragment and for protein C activation peptide) are not available for routine use.

Antithrombin III↗
PubMed2001

Prognostic and predictive value of c-erbB-2 (HER-2/neu) gene amplification in human breast cancer.

Amplification of the c-erbB-2 (HER-2/neu) proto-oncogene is detected in 10-30% of human breast cancers and has been shown to be accompanied by the overexpression of its protein in the cancer cell membrane. c-erbB-2 gene amplification is one of the first genetic alterations to be used clinically as a prognostic indicator, a predictive factor of response to doxorubicin (adriamycin) chemotherapy, and a test of patient eligibility for therapy with trastuzumab, a humanized anti-c-erbB-2 antibody. There are two types of tests to detect c-erbB-2 amplification/overexpression: immunohistochemistry and fluorescence in situ hybridization (FISH). Accurate identification of cases with c-erbB-2 amplification/overexpression requires an optimized combination of immunohistochemical and FISH tests.

Biomarkers, Tumor↗
PubMed2003

Prognostic value of troponin T, troponin I, and CK-MBmass in patients with chronic renal failure.

BACKGROUND: In patients with chronic renal failure undergoing long-term hemodialysis, ischemic heart disease accounts for up to 50% of mortality. Cardiac troponins T (TnT) and I (TnI) are frequently elevated in this patient group, but data on the prognostic relevance of these markers, especially TnI, are controversial. The aim of this study was to investigate the prognostic power of a new, sensitive TnI assay in comparison with TnT and other cardiac markers. PATIENTS AND METHODS: 104 ambulatory and in-hospital patients (41 women, median age: 65 years, interquartiles: 48-72.5 years; 63 men, median age: 63 years, interquartiles: 51.3-72.5 years) undergoing long-term hemodialysis were investigated. Patients were followed up for 6 months for all kinds of fatal events and nonfatal cardiac events. Serum levels of cardiac TnT, two TnI assays (ACS:180 and Stratus II), CK (creatine kinase), and CK-MB were measured pre- and post-dialysis. RESULTS: Pre- and post-dialysis results were not different for TnT and TnI, while CK and CK-MB levels were significantly lower post-dialysis. Elevated (pre-)dialysis levels were found in 65.7% of patients for TnT (> 0.1 microg/l), in 32.4% for TnI (ACS:180, > 0.15 microg/l), in 2.9% for TnI (Stratus II, > 0.4 microg/l), in 5.7% for CK (> 170 U/l), and in 2.8% for CK-MB (> 1.0 microg/l). 6-month events were observed in 42 patients (40.4%; 20 fatal, 22 nonfatal). The relative risk for 6-month events was calculated to be 16.0-fold for TnT and 8.5-fold for a known coronary heart disease, while both TnI and CK-MB did not predict 6-month events independently. CONCLUSIONS: TnT and a known coronary heart disease are relevant, independent risk factors in patients with chronic renal failure undergoing long-term hemodialysis.

Aged↗
PubMed2004

Differential-display PCR of peripheral blood for biomarker discovery in chronic fatigue syndrome.

We used differential-display PCR of peripheral blood mononuclear cells (PBMCs) to search for candidate biomarkers for chronic fatigue syndrome (CFS). PBMCs were collected from a subject with CFS and an age- and sex-matched control before and 24 h after exercise. RNA expression profiles were generated using 46 primer combinations, and the similarity between the individuals was striking. Differentially expressed bands were excised, reamplified, and sequenced, yielding 95 nonredundant sequences, of which 50 matched to known gene transcripts, 38 matched to genes with unknown functions, and 7 had no similarity to any database entry. Most (86%) of the differences between the two subjects were present at baseline. Differential expression of ten genes was verified by real-time reverse-transcription PCR: five (cystatin F, MHC class II, platelet factor 4, fetal brain expressed sequence tag, and perforin) were downregulated, and the remaining five genes (cathepsin B, DNA polymerase epsilon4, novel EST PBMC191MSt, heparanase precursor, and ORF2/L1 element) were upregulated in the subject with CFS. Many of these genes have known functions in defense and immunity, thus supporting prior suggestions of immune dysregulation in the pathogenesis of CFS. Differential-display PCR is a powerful tool for identification of candidate biomarkers. Investigation of these markers in samples from well-designed epidemiological studies of CFS will be required to determine the validity of these candidate biomarkers. The real-time reverse-transcription PCR assays that we developed for assay of these biomarkers will facilitate high-throughput testing of these additional samples.

Fatigue Syndrome, Chronic↗
PubMed2003

Characterisation of the progression of azaserine-induced rat pancreatic adenocarcinoma by proliferative cell nuclear antigen, basement membrane laminin and trypsinogen immunohistochemistry.

The progression of azaserine-induced rat pancreatic adenocarcinoma (AC) was characterised using quantitative and semiquantitative immunohistochemistry for proliferating cell nuclear antigen (PCNA), basement membrane laminin (BML) and trypsinogen (TG). Samples were taken 5-20 months after initiation. High PCNA-labelling indices (PCNA LIs) were measured 5 months after the induction of atypical acinar cell nodules (AACNs), which decreased later and stagnated until a further decline in the month 10 adenomas. Then a second premalignant proliferative wave was observed (month 13) within the adenoma stage. Later, in month 20 differentiated ACs PCNA LIs fell to the host tissue level but were found highest in the month 20 anaplastic ACs indicating a switch to malignant proliferation. Month 20 invasive ACs showed a number of separate proliferative foci. In early AACNs, BML decreased and remained low till the local maximum in the month 13 adenoma. Invasive ACs did not express BML. Month 5 AACN and differentiated AC were TG deficient but anaplastic AC regained its TG expression. However invasive AC was again TG negative. These results are discussed in combination with our previous data on progressional changes of autophagic capacity and microvessel densities.

Adenocarcinoma↗
PubMed2002

Surface markers of platelet function in idiopathic nephrotic syndrome in children.

The objective of the study was to investigate platelet activation markers in whole blood in idiopathic nephrotic syndrome (INS) in children. The study group consisted of 34 children with 45 relapses of INS, 35 children in long-term remission of INS, and 26 healthy controls. Using flow cytometry we measured the percentage of platelet microparticles, platelet-platelet aggregates, and surface expression of CD62P (P-selectin) and CD42b (a component of von Willebrand factor receptor). We found an increased percentage of microparticles and platelet-platelet aggregates, decreased expression of CD42b in the first 2 weeks of INS relapse. CD62P expression was elevated only at the onset of INS relapse when compared with the long-term remission group and healthy subjects. Children in long-term INS remission did not differ from healthy controls. There was no significant correlation between platelet activation markers and selected biochemical factors of blood in children with INS. Activation of the coagulation cascade was confirmed by an elevated serum concentration of F1+2 prothrombin fragment during follow-up. These findings suggest that platelets may contribute independently to the prothrombotic state in the early stages of INS, but their role in triggering relapses remains to be investigated.

Adolescent↗
PubMed2001

Evaluation of thrombogenicity of fluoropassivated polyester patches following carotid endarterectomy.

The use of a patch after carotid endarterectomy (CE) is recommended to reduce the incidence of restenosis. Most studies on this subject report the implantation of saphenous vein or PTFE patches, because polyester has always been considered to be a thrombogenic material. The purpose of this study was to evaluate the thrombogenicity of a knitted polyester patch passivated by fluoropolymer surface treatment (FPD patch), which experimental studies have demonstrated to be less thrombogenic than other materials. This prospective, randomized study was performed in 22 patients who underwent CE. In 11 patients the arteriotomy was sutured directly, while in the other 11 an FPD patch was applied. Patients' 111in-oxine labeled platelets were reinjected on the first postoperative day, and scintigraphies were performed after 4, 24, and 48 hr, respectively. The study confirmed that an FPD patch is no more thrombogenic than a simple carotid endarterectomy. The application of the patch, therefore, can be recommended to reduce restenosis without any adjunctive thromboembolic risk.

Aged↗
PubMed2005

Cytidine deaminase in polymyalgia rheumatica and elderly onset rheumatoid arthritis.

Serum cytidine deaminase (CD) as a marker of inflammatory disease was assessed in 44 patients and 47 controls to differentiate polymyalgia rheumatica (PMR) from elderly onset rheumatoid arthritis (EORA). The patients were divided into four groups: PMR with and without synovitis and seropositive and seronegative EORA. No statistically significant differences were found when serum CD levels of seropositive EORA patients were compared with serum CD of PMR patients without synovitis, neither when serum CD levels of all PMR patients were compared with a seronegative EORA group, nor when serum CD levels of PMR patients with synovitis were compared with those with EORA. Nevertheless, statistically significant differences were detected between EORA's serum CD levels and the control group (p=0.023). This difference was 10% when comparing CD levels of PMR patients with the control group (p=0.070). We did not demonstrate that serum CD levels could be a useful tool to differentiate PMR from EORA, but these findings could nevertheless reflect the presence of an inflammatory disease.

Aged↗
PubMed2005

Conference overview: molecular mechanisms of metal toxicity and carcinogenesis.

Chronic exposure to many heavy metals and metal-derivatives is associated with an increased risk of cancer, although the mechanisms of tumorigenesis are largely unknown. Approximately 125 scientists attended the 3rd Conference on Molecular Mechanisms of Metal Toxicity and Carcinogenesis and presented the latest research concerning these mechanisms. Major areas of focus included exposure assessment and biomarker identification, roles of ROS and antioxidants in carcinogenesis, mechanisms of metal-induced DNA damage, metal signalling, and the development of animal models for use in metal toxicology studies. Here we highlight some of the research presented, and summarize the conference proceedings.

Animals↗
PubMed1992

Early detection of coronary artery patency after thrombolysis by determination of the MM creatine kinase isoforms in patients with acute myocardial infarction. PRIMI Study Group.

To evaluate the role of MM creatine kinase isoforms in detecting infarct vessel patency in 84 patients with acute myocardial infarction, total creatine kinase, MB creatine kinase, and MM isoforms were determined at the start of thrombolytic therapy and 30, 60, and 120 minutes later. Enzyme data were related to the reperfusion grade of the infarct artery, which was assessed by angiography 60 and 90 minutes after the start of thrombolysis. In 50 patients the infarct vessel was found patent at 60 and at 90 minutes after thrombolysis; in 19 patients it was occluded at both time points. In contrast to the patients with a persistently occluded infarct artery, in the patient group with a patent infarct vessel total creatine kinase and MB creatine kinase increased significantly at 60 minutes after the start of thrombolysis and MM3 creatine kinase activity and the ratio MM3:MM1 had already increased at 30 minutes after the start of thrombolytic therapy. The increases from baseline of creatine kinase and creatine kinase MB activity were significantly higher 120 minutes after the start of thrombolysis; increases of creatine kinase MM3 and the ratio of MM3:MM1, however, by 60 minutes after the start of thrombolysis were already increased compared with the increases in enzyme activity in patients with an occluded artery. Thus the rise in MM3 creatine kinase and the ratio of MM3:MM1 can be used for early detection of reperfusion after intravenous thrombolytic therapy in acute myocardial infarction.

Adult↗