bluuebunny/crossref_metadata_2025 huggingface dataset:
Strategy of IFCC standardization and use of cardiac markers in acute coronary syndromes
Authors: Ignjatovic Svetlana
Published: August 2005

Although the use of troponin to diagnose acute myocardial infarction (AMI) has been previously proposed, the Committee on Standardization of Markers of Cardiac Damage (C-SMCD) of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) made a recommendation in 1999 to expand on the enzyme diagnostic criteria for AMI to include cardiac-specific proteins. In September 2000, a joint committee of the European Society of Cardiology and the American College of Cardiology (ESC/ACC) published a new definition of AMI that for first time officially included troponin. According to these criteria, as the best biochemical indicator for detecting myocardial necrosis is "a concentration of cardiac troponin exceeding the decision limit (defined as the 99th percentile of a reference control group) on at least one occasion during the first 24 hours after the onset of clinical event". The use of creatine kinase MB (CK-MB), measured by mass assays, is still considered as an acceptable alternative only if cardiac troponin assays are not available. It is very important to standardize the clinical use of troponin in diagnosis and management of acute coronary syndromes and to clearly define decision thresholds. Two strategies have competed as the most appropriate for the use of new markers. The first relies on the use of a combination of two markers - a rapid rising marker such as myoglobin, and a marker that takes longer to rise but is more specific, such as cardiac troponin - to enable detection of AMI in patients who present early and late after symptom onset. In the second strategy, only measurement of cardiac troponin is suggested. One of the most important problems in the practical use of the cardiac-specific troponin is the right definition of decision limits. As diagnostic cut-off for clinical use, the IFCC C-SMCD recommends for troponin assays a total imprecision, expressed as coefficient of variation (CV), of <10% at the 99th percentile of a reference control group. For troponin assays that cannot presently meet the 10% CV at the 99th percentile value, a predetermined higher concentration that meets this imprecision goal should be used as cut-off for AMI until the goal of a 10% CV can be achieved at the 99th percentile. It is very important that clinically relevant biomarker, such as cardiac troponin, on which critical decisions will rest, can be measured with highly reliable and standardized methods. There are problems in assay standardization, imprecision interference, and of pre-analytical variability. Cardiac troponin is currently the most sensitive and specific biochemical marker of myocardial damage and is the best marker for diagnosis, risk stratification, and guidance of therapy in acute coronary syndromes.
Comparative analysis of expression of angiogenic factors and CD44 gene in human glioma and neuroblastoma cell lines in vitro
Authors: Jankovic Dragana , Stojkovic Ana , Pesic Milica , Kanazir Selma , Rakic Ljubisav , Ruzdijic Sabera
Published: August 2005

Angiogenesis is essential for tumor growth and relies on the production of angiogenic factors. By comparative analysis using RT-PCR method of angiogenic growth factors: VEGF, bFGF, PDGF-A, angiogenin- 1 and IL-8 we established the level of expression of these genes necessary for angiogenesis in glioma and neuroblastoma cell lines. Our analyses were also extended to CD44 gene, which plays an important role in cascade of metastasis and progression of brain tumors. Significant differences in the level of gene expression of angiogenic factors and CD44 gene between the two cell lines observed throughout this study can be used as a prognostic marker for predicting clinical outcome in human brain tumors at the time of the initial staging.
Study of some polyoxometallates of Keggin's type as potential antitumour agents
Authors: Holclajtner-Antunovic Ivanka , Kuntic Vesna , Juranic Zorica , Filipovic Ivana , Mioc Ubavka , Stanojkovic Tatjana , Zizak Zeljko
Published: August 2005

The antitumour action of three polyoxometallate compounds of Keggin's type: 12-molibdophosphoric acid (MoPA), 12-tungstophosphoric acid (WPA) and Mg salt of WPA (MgHWPA) was studied in vitro. For human cervix carcinoma (HeLa) cells survival, as well as for nonstimulated and stimulated peripheral blood mononuclear cells (PBMC), MTT test was applied and IC50 values of POMs were determinated. Index selectivity for WPA and MgHWPA are 1.9 and 1.8, calculated for nonstimulated, as well as 2.5 and 2.0, calculated for stimulated PBMS. Combination of studied POMs do not contribute to their lower IC50 values. Apoptosis detection implies mild cytotoxic effect of WPA and more cytostatical effect of MgHWPA. Combination of each of the studied POMs with caffeine decreases HeLa survival in dose dependent way. None of the studied POMs in the used concentrations (up to 100 mmol/L) damages blood cells and/or decreases their number.
Is insulin an independent predictor of mortality in hemodialysis patients?
Authors: Rasic-Milutinovic Zorica , Perunicic Gordana , Pljesa Steva , Ristic Vanja , Ristic Gordana , Milic Natasa , Ilic Mirka
Published: August 2005

Reduced insulin sensitivity is present in patients with end-stage renal failure (ERF). It has been established in general population that insulin resistance is a cardiovascular risk factor. The present study examines the potential effect of insulin action and secretion on over-all and cardiovascular mortality in non-diabetic haemodialysis (HD) patients. Sixty two patents (age 52.5 ? 10.3 year) on maintenance haemodialysis (5.4 ? 3.1 year) were recruited in June, 1994 and were followed-up over a 5-year period. At the end of the study we had two those who survived and those who died: survivals and deaths. All basic clinical indicators (age, gender, duration of dialysis prior to entry into the study, blood pressure, serum proteins, albumins, lipids and lipoproteins, urea, creatinine, dialysis dose defined by Kt/V, protein catabolic rate-nPCR, glucose, insulin, C peptide, IR-HOMA and % b- HOMA) were screened for a significant relation to outcome by univariante logistic regression models. Multiple logistic regression analysis was used to evaluate potentional independent predictors of death. Patients of both groups, survivals (n=42) and deaths (n=20), had a comparable duration of HD before the study, and as to blood pressure, serum proteins, albumines, lipids and lipoproteins A and B 100, lipoprotein (a), glucose, glycosylated haemoglobin, and Kt/V there were no significant differences. Patients who died were significantly older, and they had lower values of urea, creatinine, insulin, C-peptide and nPCR. Multiple logistic regression analysis indicated that only insulin and nPCR were significantly and independently associated with all-cause mortality and cardiovascular mortality, and age was an important confounding factor. These results suggest that we need an early procedure to preserve beta-cell function, besides positive nitrogen balance, to reduce cardiovascular and over-all mortality in haemodialysis patients.
Is soluble intercellular adhesion molecule 1 a marker of disease activity in bronchial asthma?
Authors: Bogic Mirjana , Peric-Popadic Aleksandra , Jovicic Zikica , Kovacevic Snezana , Raskovic Sanvila , Tomic-Spiric Vesna , Savic Nevena , Colic Miodrag
Published: August 2005

Increased number of neutrophils, eosinophils and lymphocytes in the airway mucosa in the course of asthma exacerbation develops simultaneously with increase of expression of the specific adhesion molecules (including intercellular adhesion molecule 1) on the postcapillary venulae of the endothelial cells. Our study was aimed at measurement of concentration of soluble intercellular adhesion molecule 1 (sICAM-1) in 7 patients with bronchial asthma in phase of exacerbation, and evaluation of correlation between the obtained value and sICAM-1 concentration obtained in the same patients in the stable state subsequent to seven-day glucocorticosteroid therapy, as well as in comparison to the healthy controls (10 subjects). Mean value of sICAM-1 concentration in patients with asthma exacerbation and healthy controls was 430.49 ng/mL and 260.9 ng/mL, respectively. sICAM-1 concentration was found to be statistically significantly higher in patients with exacerbating asthma in comparison to the healthy controls (Z = ? 2.246), as well as in comparison to the same patients in the stable state subsequent to seven-day glucocorticosteroid therapy (Z = ?2.197).
Role of medical laboratories accreditation
Authors: Markicevic Ljiljana
Published: August 2005

Accreditation is an instrument which confirms competence according to the international standards. Accreditation Body of Serbia and Montenegro (JUAT) is a federal body which manages accreditation system in Serbia and Montenegro. Within its activities of determining competency of organizations for carrying out certification of conformity assessment it also carries out the accreditation of testing laboratories. Within this kind of accreditation very important place belongs to the accreditation of medical laboratories. Generally, requirements for the competence of testing laboratories are given in standard JUS ISO IEC 17025 which cover testing process. A the medical laboratories have broader field of activity than the usual one for testing laboratories and as they include preanalytical, analytical and postanalytical phase of activity, it is necessary for general requirements to be adapted to the additional specifically requirements related to the activities of medical laboratories. It is those additional requirements that are recognized by the standard ISO/IEC 15189 Quality Management in the Medical Laboratory. For these reasons JUAT has established a commission for generating the accreditation scheme for laboratories in the field of medicine with the task to build and develop accreditation scheme for medical laboratories. In this project for accreditation scheme of medical laboratories development, JUAT has included known and respectful experts in medical science, who will contribute by their expertise, experience and competency in establishing and implementation of requirements necessary at accreditation of medical laboratories.
Influence of increased cadmium intake on antioxidative defence system
Authors: Matovic Vesna , Plamenac-Bulat Zorica , Djukic Danijela
Published: August 2005

During the last decades it was proven that many xenobiotics (certain solvents, pesticides, metals and even drugs) induce increased formation of free radicals that cause cell disfunction of lipids, proteins, nucleic acids and even cell death. Cadmium, an important source of occupational as well as environmental pollution, has significant role. Numerous investigations indicate that increased cadmium intake induces oxidative modifications of biomolecules. It is unclear whether this effect is direct and/or indirect, due to the influence of cadmium on antioxidative defence system. This paper presents the effect of acute and chronic cadmium intoxication on antioxidative system in order to give more explanation on mechanism of cell damaging effects of this toxic metal. Experimental studies indicate that cadmium induce negative effects on enzyme activity of antioxidative defence system (superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase), as well as on nonenzymatic components (ascorbic acid, alpha-tocopherol, coenzyme Q, glutathione and metallothionein).
Gene expression analysis by non-radioactive RNA-RNA in situ hybridization techniques
Authors: Drakulic Danijela , Stevanovic Milena , Nikcevic Gordana
Published: August 2005

RNA-RNA in situ hybridization is a reliable method for studying tissue and cell specific gene expression, which enables visualization of labeled antisense RNA probe hybridized to specific mRNA. In this study we employed non-radioactive RNA-RNA in situ hybridization using biotin- or digoxigenin-labeled RNA probes in order to detect SOX gene expression in carcinoma cell lines. By this approach we confirmed results obtained by Northern blot analysis, where the presence of SOX2 mRNA in NT2/D1 and SOX14 mRNA in HepG2 cells has been established. Our aim was to set up RNA-RNA in situ hybridization method in in vitro cultured cells in order to perform further analyses of SOX gene expression on various normal and cancer tissues.
Flow cytometry evaluation of HeLa S3 cell death induced by gamma-radiation
Authors: Niciforovic Ana , Zaric Bozidarka , Dakic Aleksandra , Tisma Nevena , Radojcic Marija
Published: August 2005

In this study we followed the effects of radiation on human uterin cervix HeLa S3 cells viability, morphology and DNA structure 2-96 hours after treatment with 2-10 Gy from 60Co gamma radiation source. Staining of cells with Annexin V-FITC and propidium iodide showed very low degree of radiation-induced apoptosis. The prevailing form of HeLa S3 cell death according to flow-cytometry, DNA fragmentation and fluorescent microscopy, was necrosis. The gamma-radiation dose necessary to induce 50% of necrosis (termed DD50) was twice higher compared to dose that induced 50% inhibition of cell proliferation (LD50). These in vitro data suggested, that the increase in radiation dose might eradicate tumor cells, rather than just control their proliferation and growth.
The analysis of acid-base balance in haemodialyzed patients and the effect of etiology of chronic renal failure on acid-base parameter values
Authors: Colak Emina , Stankovic Sanja , Majkic-Singh Nada , Radovic Milan
Published: August 2005

Due to reduced scope of renal function in chronic renal failure (CRF) it is not rare that it comes to marked metabolic acidosis and pathologic catabolism associated with hypoxia. The cause of metabolic acidosis is deminished tubular secretion of ammonia, due to reduced synthesis, stipulated by lower number of renal canaliculi. Acid-base balance was analyzed in 74 patients suffering from CRF who were on haemodialysis program. Heparinised blood was taken from these patients before and after haemodialysis in which the following parameters were measured: pH, pCO2, pO2, HCO-3 ?, TCO2. The aim of this study was the monitoring of patients' acid-base status before and after haemodilalysis in order to evaluate the degree of stabilization of acid-base balance after haemodilalysis and also to define the correlation between the etiology of CRF and the degree of acid-base balance disorder. In relation to underlying disease resulting in CRF, the patients were divided into five groups: I-tubular interstitial nephrosis (TIN), II-polycystic kidney disease (ADPKD), III-glomerulonephritis (GN), IVhypertension and nephroangio-sclerosis (HTA-Nascl) and V-consisting of patients whose underlying disease was not diagnosed (ERSD). The obtained values of pH, HCO2 and TCO2 after haemodialysis (pH = 7.428 ? 0.06; HCO-3 ?= 25.4 ? 3.44 mmol/L; TCO2 = 26.57 ? 3.56 mmol/L), were significantly increased (p<0.001), in relation to values before haemodialysis (pH = 7.350 ? 0.05; HCO-3 ?= 20.88 ? 2.92 mmol/L; TCO2 = 22.03 ? 3.00 mmol/L). There was no statistically significant difference in values of measured parameters (p>0.05) in relation to underlying disease either before or after haemodialysis both in males and females.
Potential role of P-selectin glycoprotein ligand-1 in haematological diseases
Authors: Kappelmayer János
Published: August 2005

PSGL-1 is a major counterreceptor of all three types of selectins that is expressed in several leukocyte subsets. Data presented, here prove that this mucin may be implied in haematological disorders. We established on normal peripheral blood and in samples derived from 20 AML patients that PSGL-1 is differently expressed in various leukocyte subsets. Myeloblasts appearing in acute myeloid leukaemia patients express significantly less PSGL-1 (12 000 ? 5300) than mature neutrophils (p< 0.001). In monocytic leukaemias, however, the amount of PSGL-1 on monocytic precursors is displayed in a fairly broad range which was not significantly different from that of mature monocytes (p=0.084). Monoblasts/promononocytes possess more PSGL-1 than myeloblasts and the expression pattern is completely non-overlapping. This would imply a differential expression of PSGL-1 during myeloid haemopoietic development and suggests, that the quantitation of surface PSGL-1 may help in differentiating myeloblasts from monoblasts by immunophenotyping in different AML subsets. PSGL-1 has also a certain role in the generation of procoagulant microparticles (MP) as in the PSGL-1 knockout mouse the MP number failed to increase with age and the MP contained significantly less tissue factor than wild type mice. Since PSGL-1 P-selectin interaction is crucial in generating a procoagulant effect we tested the hypothesis that the administration of a P-selectin IgG chimera (Psel-Ig) corrects bleeding tendency in a murine haemophilia model and in human haemophilic blood. The addition of Psel-Ig resulted in significant improvement of the bleeding tendency in mice and in the generation of MP in human hemophilic blood. Thus, the Psel-Ig can become an alternative route to control bleeding tendency in coagulopathies.
Cerebral ischaemic attack in asymptomatic hepatitis c virus infection
Authors: Cojocaru Manole , Cojocaru-Inimioara Mihaela
Published: August 2005

We tried to correlate the onset of the cerebral ischaemic attack accompanied by mixed cryoglobulinaemia with the asymptomatic hepatitis C virus infection. We studied a group of 12 patients with asymptomatic hepatitic C virus infection associated with ischaemic stroke (antihepatitis C virus antibodies-ELISA). Ischaemic stroke occurred in equal proportion in women and men. The patients were not aware of infection at that moment. All patients had type II mixed monoclonal cryoglobulinaemia, hypergammaglobulinemia with polyclonal IgG and monoclonal IgM, blood hyperviscosity, high level of cryocrit, rheumatoid factors-positive, and normal serum alanine aminotransferase levels, despite the replication of hepatitis C virus in infected liver cells and detection of HCV-RNA in serum, HBs antigen-negative, anti-HBs antibody-negative; anti-HCV antibody-positive, antinuclear antibodies-false positive. Immunological tests for autoantibodies, namely, anti-Sm antibody, anti-RNP antibody, anti-SS-A and -B antibodies, and anti-Scl antibody were not detectable due to a high level of serum cryoglobulin. Cryoglobulin was washed several times with an isotonic chloride solution for purification, then subjected to immunological analyses. The purified cryoglobulin contained monoclonal IgM-kappa, polyclonal IgG. Cryoglobulinemia is a risk factor of ischaemic stroke, it causes arterial thrombosis. The long-term exposure to antigens and the autoimmune background may have developed IgM anti-idiotype auto-antibody against the high level of anti-HCV IgG.
Total quality management, laboratory accreditation and external quality assessment schemes
Authors: Thakur Singh
Published: August 2005

Two contradictory pressures, ?high quality? and ?cost reduction? require the clinical laboratories to adopt effective management techniques such as Total Quality Management (TQM). It is not merely a management process for quality improvement in all spheres of industrial functioning but also a management philosophy for overall organization development. TQM has been adopted by many health care organizations including clinical laboratories in the developed world. In the developing countries, however, majority are still using the traditional frame work of quality management. Through the concept of Quality Assurance (QA) and Quality Control (QC) in health care laboratories in India is more than two decades old, it developed in a highly unequal plane and still faces multi factorial problems. External QA/ Proficiency Testing (PT) is used to compare performance of laboratories. This is recently made mandatory for accreditation process in India. Unfortunately only <10% of laboratories participate in EQA programs possibly due to high cost. Professional bodies/Institutions (ACBI, IAPM, ISHTM-AIIMS EHPT) and Government of India are working hard to make EQA Programs available at reasonable cost. National Board of Testing and Calibration Laboratories (NABL) has been setup by Department of Science and Technology, Government of India which has started accreditation of clinical laboratories since 1999. So for 33 laboratories (0.17%) has been accredited and almost the same number of applications are in process. The program is voluntary at the beginning, may be made mandatory later. We see a Herculean task ahead for NABL but they are doing a good job at low cost similar to international organization like ACP. The formation of laboratory policy with quality control as its integral part is very imperative in achieving, total quality management of clinical laboratories in India.
Cell death in irradiated prostate cancer cells assessed by flow cytometry
Authors: Vucic Vesna , Adzic Miroslav , Niciforovic Ana , Tisma Nevena , Ruzdijic Sabera , Radojcic Marija
Published: August 2005

Despite the significant advances in cancer chemotherapy, radiotherapy still remains a method of choice for treatment of metastatic human prostate cancer. This study presents quantitative analysis of 60Co gamma-radiation effects on cell growth and cell death of metastatic human prostate cancer PC-3 cell line, performed in time (24-72h) and dose (2-20 Gy) dependent manner. The irradiated PC-3 cells were mostly dying by necrosis at late time intervals (72h), while apoptotic cell death was negligible. The EC50 or 50% of cytotoxicity was not achieved within the radiation doses used (2-20 Gy), but significant cell growth inhibition with IC50 of 10.4 Gy was observed. It is concluded that the increase in the radiation dose may have an important cytostatic effect, but for the complete eradication of metastatic prostate cancer novel cytotoxic drugs and radiosensitizers should be introduced as adjuvant.
CFTR gene analysis in patient with atypical cystic fibrosis
Authors: Nikolic Aleksandra , Divac Aleksandra , Bogdanovic Nada , Mitic-Milikic Marija , Radojkovic Dragica
Published: August 2005

This paper reports a case of a patient presenting with atypical cystic fibrosis whose sweat test shows borderline values. In vast majority of cases the sweat test is essential diagnostic tool for establishing the diagnosis of cystic fibrosis, but only after the molecular genetic testing the diagnosis can be confirmed. The patient was found to be compound heterozygote for two CFTR mutations, F508del and D1152H. The presence of F508del mutation was analyzed by PSM method, while the screening for the second mutation was performed using DGGE. The strategy of mutation detection in cystic fibrosis patients, especially those with atypical presentations who carry less frequent mutations, should include both direct and indirect methods of molecular diagnostics.
Biochemical phenotype and origin of the three most common beta-thalassemia mutations in Serbia
Authors: Poznanic Jelena , Perisic Ljubica , Urosevic Jelena , Petrucev Branka , Djureinovic Tatjana , Tosic Natasa , Krivokapic-Dokmanovic Lidija , Janic Dragana , Cvorkov-Drazic Milica , Bunjevacki Gordana , Pavlovic Sonja
Published: August 2005

Molecular (DNA) characterization of thalassemia is the most reliable methodology for the diagnosis of this group of diseases. As thalassemias are very heterogeneous, hematological data and additional biochemical analysis are essential for their differential diagnosis. In this paper we present hematological and biochemical characteristics of the carriers of three most common beta-thalassemia mutations in Serbia (Hb Lepore, b?39 and b+IVS-I-110), to be taken into consideration as the initial step of the diagnostic approach to the thalassemia patients. Also, this paper represents a detailed survey of the diversity of b-globin gene haplotypes in carriers of the most common b-thalassemia mutations and normal betaA/betaA individuals of Serbian descent. A novel haplotype associated with Hb Lepore-Boston-Washington gene has been identified in Serbian population. These data support the hypothesis of multicentric origin of this mutation. The mutation has arised de novo in the chromosomal background characteristic for Serbian population. Additionally, we have shown that two most common Mediterranean mutations, b?39 and b+ IVS-I-110, have probably been introduced into Serbian population from Italy and Turkey, respectively, through historically documented migrations and settlements.
Effect of thyroxine on glutathione-dependent antioxidant enzyme activities and glutathione content in the interscapular brown adipose tissue of different maturated rats
Authors: Saicic Zorica , Mijalkovic Dejan , Nikolic Aleksandra , Blagojevic Dusko , Spasic Mihajlo , Petrovic Vojislav
Published: August 2005

Effect of thyroxine on glutathione-dependent antioxidant enzyme activities and glutathione (GSH) content in the interscapular brown adipose tissue (IBAT) of different aged rats were studied. Male Mill Hill hybrid hooded rats aged 15, 45 and 75 days were treated with L-thyroxine, T4 (40 mg/100 g body mass), s.c., one dose per day, 14 days (finally aged 30, 60 and 90 days, respectively). Effect of T4 on GSH-dependent antioxidant enzyme activities in the IBAT differs with respect to age. T4 treatment gradually decrease activities of all GSH-dependent antioxidant enzymes in 60 and 90 days old rats in comparison to young ones. GSH content in animals of 30 and 60 days old rats are lower in comparison with 90 days old rats, but the effects are oppposite. L-thyroxine treatment significantly increase GSH content in 30 days old rats (p<0.001) in respect with coresponding controls, while decrease in 60 and 90 days old animals were detected (p<0.01). Different response of non-mature rats to thyroxine comparing to older rats could be attributed to the difference in thyroxine metabolism and developmental phase of regulatory physiological systems maturation including antioxidative.
Inflammatory response in rheumatoid arthritis
Authors: Petrovic-Rackov Ljiljana , Pejnovic Nada , Mijuskovic Zoran , Ercegovic Gordana
Published: August 2005

The aim of the research is to determine the clinical significance of cytokines TNF-alpha, IL-12, IL-15 and IL-18 in evaluation of the activity of rheumatoid arthritis (RA). By comparing the concentrations in 30 patients with high, 14 patients with moderate and 20 patients with mild activity of RA it is established that the patients with high degree of disease activity, have significantly high (p<0.01; p<0.05) concentrations of examined cytokines and rheumatoid factor in blood and synovial fluid as well as C-reactive protein in serum in relation to patients with moderate and mild active disease. We have concluded that the cytokines concentrations can be good indicators of the degree of the general activity of RA. This research can contribute to interpretation of insufficiently well known views of pathogenesis role of cytokines in active disease.
Somatostatin levels in gastrointestinal disease
Authors: Kostic Nada , Brkic Branislava , Caparevic Zorica , Milosevic Verica
Published: August 2005

Serum levels of somatostatin were determined by RIA method in 50 patients with liver cirrhosis, 15 with pernicious anemia and atrophic gastritis, 31 with inflamatory bowel disease, 32 with colorectal tumors and in 40 control persons. In patients with liver cirrhosis somatostatin levels were significantly higher than in control group (p<0.01). Patients with pernicious anemia and ulcerative colitis in acute phase of the disease had significantly lower levels of somatostatin (p<0.01) (p<0.005). In patients with colorectal tumors somatostatin were significantly lower then in control group (p<0.01). Our results show that the liver is involved in somatostatin metabolism. Atrophic gastritis, ulcerative colitis and M. Crohn, so as colorectal neoplasia were associated with significantly changes in somatostatin levels which suggest the potential pathophysiologic and terapeutic role of somatostatin in those disease.
Determination of high sensitivity C-reactive protein: Clinical and analytical quality
Authors: Ignjatovic Svetlana
Published: August 2005

Inflammation plays a key role in the pathophysiology of atherosclerotic disease. A number of inflammatory markers that are measurable in blood have been investigated for their ability to predict the risk of future atherosclerotic events. High-sensitivity (hs) measurement of C-reactive protein (CRP) has received a great deal of attention recently for use as an atherosclerotic risk marker. For these reasons, CRP is currently the inflammatory marker of choice. The Centers for Disease Control and Prevention (CCDC) and the American Heart Association (AHA) issued guidelines for the utility of this marker in the primary prevention setting and in patients with stable coronary disease or acute coronary syndromes. The guidelines also included specific recommendations that pertain to the laboratory aspect of CRP and defined cut-points for clinical interpretation; CRP concentrations <1 mg/L are considered low, 1-3 mg/L average, and >3 mg/L high relative risk. A number of preanalytical and analytical factors including specimen type and stability, assay imprecision, commercial availability, and standardization are reviewed here. Better control of preanalytic and analytic sources of variations will undoubtedly lead to improvement in CRP measurements. Further research is required to better define the performance characteristics necessary for assays bearing the designation hsCRP. These characteristics include developing guidelines for total analytical error from a careful review of the intraindividual biological variability of the analyte under conditions that will be encountered in clinical practice, defining allowable random and systematic error limits based on this information, validating these guidelines in the clinical setting, and completing the standardization efforts.
Phenylethylamine effects on histamine-induced contraction of isolated guinea-pig trachea rings
Authors: Rosic Gvozden , Lazic Zorica , Pantovic Suzana , Rosic Mirko
Published: August 2005

Histamine produces constriction of tracheal smooth muscle via H1 receptors, but it also decreases tracheal smooth muscle tone via H2 and H3 receptors. In addition, it has already been reported that phenylethylamine is competitive antagonist of histamine N-methyl-transferase (HMT), enzyme responsible for rapid inactivation of histamine. Our results suggest possibility that phenylethylamine as competitive antagonist of histamine N-methyl-transferase leads to potentiation of histamine induced constriction of isolated guinea-pig trachea, which could be consequence of decreased histamine methylation and subsequent histamine inactivation. At the same time, phenylethylamine had no direct effect on basal tone of intact isolated trachea rings, as well as on other mechanisms leading to increased responsiveness of guinea-pig tracheal smooth muscle (acetylcholine, KCl, electro stimulation).
Oxidized LDL and other lipids as risk factors for cardiovascular disease in the patients with metabolic syndrome
Authors: Trifunovic Danijela , Milicic Tanja , Potpara Tatjana , Colak Emina
Published: August 2005

We estimated relationship between lipids, LDL oxidation, antioxidant activity and CRP in diabetic patients with metabolic syndrome (MS), with and without coronary heart disease (CHD), in non diabetic patients with and without CHD and in obese patients, with and without diabetes. We didn't-t find significant difference in lipids among diabetic MS patients. Patients from all subgroups have similar level of oxLDL, but significant higher comparing with healthy control. MS diabetic patients have oxLDL in positive correlation with TC, LDL-C, non HDLC and apo B 100, as vell as with molar ratio LDL-C/HDL-C and TG/HDL-C (p<0.001). Among non diabetics, CHD patients had higher Lp(a), but oxLDL was similar in both subgroups. In the nondiabetics we found correlation between oxLDL, TC, LDL-C and TG (p<0.01) and apo B 100 (p<0.001), but not with TG/HDL-C molar ratio. Obese patients from both groups had similar lipids profile but, oxLDL was higher, not significant, in non diabetics. We didn't-t find significant differences in antioxidative activity and CRP in both diabetics MS subgroups, and both obese subgroups. Nondiabetics with CHD have lower E-SOD and E-GPX activity and higher level of CRP than non CHD patients (p<0.05). MS diabetics and non diabetics didn't have significant correlation between levels of oxLDL and CRP, but CHD patients (with or without diabetes) had (p<0. 01).
Assay performance and clinical validation of a radioimmunoassay for serum thyroxine-binding globulin
Authors: Petrovic Ivana , Savin Svetlana , Cvejic Dubravka
Published: August 2005

A radioimmunoassay for the quantitation of serum thyroxine-binding globulin (TBG), RIA TBG (PEG) - INEP, was formed and characterised. Test sensitivity was found to be favorable (2.0 mg/L). The highly satisfactory precision of the assay was reflected in the low coefficients of variation (less than 5%) found for both intra- and interassay precision at three concentrations. Non-specific binding of the labeled antigen was less than 2% of the total binding. Linearity of the assay within the range of the standard curve (0-80.0 mg/L) was excellent (r =0.99) and the analytical recovery of TBG added to serum ranged from 91 to 115%. Reproducibility was checked by determining the concentration of TBG in samples of sera over a period of 32 days from the day of antigen iodination and F<Ftab 0.05, F0.05 7, 32 = 2.31. The assay was standardized for accuracy using Lyphochek Immunoassay Controls (Bio-Rad). A significant correlation was obtained between RIA TBG (PEG) and the Kodak Amerlite TBG Assay (r = 0.84; n = 25). The presented results show that RIA TBG (PEG) is a sensitive, precise and reliable method for determination of TBG in human sera. Assay reference ranges were established for sera from various subjects: euthyroid adults, hypothyroid and hyperthyroid patients and in healthy pregnant women.
The isolation of (6S, 9S)-cyclo (prolylvalyl) from marine actinomycete, by use of high speed contercurrent chromatography
Authors: Smelcerovic Andrija , Schiebel Mirko , Djordjevic Sinisa
Published: August 2005

The marine actinomycete B 1758 came from the actinomycete collection of the Alfred Wegener Institute for Polar and Marine Research in Bremerhafen Germany. 1.079 g of raw extract was obtained by fermentation. Seven fractions were separated by column chromatography on silica gel. Fraction 4 was separated by high speed countercurrent chromatography. Fraction 4.6 yielded 5.2 mg of (6S, 9S)-cyclo(prolylvalyl).
The reactivity of α,β-unsaturated carboxylic acids. Part XVI. The kinetics of the reaction of cycloalkenecarboxylic and cycloalkenylacetic acids with diazodiphenylmethane in various alcohols
Authors: Uscumlic Gordana , Nikolic Jasmina , Krstic Vera
Published: August 2005

The rate constants for the reaction of diazodiphenylmethane with 1-cyclopentenecarboxylic, 1-cycloheptenecarboxylic, cyclopent-1-enylacetic and cyclohept-1-enylacetic acids were determined in eight alcohols at 30 ?C using the appropriate UV-spectroscopic method. In order to explain the kinetic results through solvent effects, the second order rate constants of the examined acids were correlated using a total solvatochromic equation, of the form: log k = A0+ s?*+a??+ b?, where ?* is a measure of the solvent polarity, ??represents the scale of solvent hydrogen bond acceptor basicities and ? represents the scale of solvent hydrogen bond donor acidities. The correlations of the kinetic data were carried out by means of multiple linear regression analysis. The opposite sings of the electrophilic and the nucleophilic parameters are in agreement with the well-known reaction mechanism. The results presented in this paper were compared with the kinetic data for 1-cyclohexenecarboxylic and cyclohex-1-enylacetic acids obtained under the same experimental conditions.
Two theorems on connectivity indices
Authors: Gutman Ivan
Published: August 2005

Two general cases are pointed out for which the ordering of molecules according to the connectivity index C(?) is the same for all values of the exponent ?.
Heats of formation for the azine series: A Gaussian-3 study
Authors: Cheng Mei-Fun , Ho H.O. , Lam C.S. , Li W.K.
Published: August 2005

Applying the Gaussian-3 (G3) model and its variant G3(MP2), and using the atomization scheme, the heats of formation (?Hf) at 0 K and 298 K have been calculated for twelve monocyclic azines with the general formula Nn(CH)6-n n = 1, 2,?, 6. Upon comparing the calculated results with available experimental data, it is found that the calculated structural parameters agree very well with the experimental ones. Additionally, most of the calculated ?Hf values are well within ?10 kJ mol-1 of the available experimental data. Thus, it is concluded that the unfavorable accumulation of component errors found in the Gaussian-2 methods is greatly reduced in the G3 models. Also, the calculated ?Hf values for those azines for which no experimental data exists should be reliable estimates.
Solvent extraction of Sc(III) from sulfuric acid solution by bis(2-ethylhexyl) phosphonic acid in toluene
Authors: Koladkar Devendra , Dhadke Purshottam
Published: August 2005

Liquid-liquid extraction of scandium(III) from sulfuric acid solution using bis(2-ethylhexyl) phosphinic acid (PIA-8) in toluene has been studied. The extraction of scandium(III) was found to be quantitative with 0.03 M PIA-8 in toluene in the acidic range of 0.1?0.5 M and 6.0?8.0 M H2SO4. The effect of the reagent concentration and other parameters on the extraction of scandium(III) was also studied. The stoichiometry of the extracted species of scandium(III) was determined on the basis of the slope analysis method. The extraction reaction proceeds via the cation exchange mechanism in the H2SO4 concentration range of 0.1?0.5M and the extracted species is ScR3.3HR. However, at higher acidity (6.0M?8.0M H2SO4) it proceeds by solvation. The extracted species is HSc(SO4)2.4HR. The temperature dependencies of the extraction equilibrium constants were examined to estimate the apparent thermodynamic functions (?H, ?S and ?G) for the extraction reaction.
Chemical applications of the Laplacian spectrum. VI On the largest Laplacian eigenvalue of alkanes
Authors: Gutman Ivan , Vidovic Dusica , Stevanovic Dragan
Published: August 2005

The largest Lapacian eigenvalue ?1 of the molecular graph is a quantity important in the theory of the photoelectron spectra of saturated hydrocarbons. It is shown that in the case of alkanes, the presence or absence of quaternary carbon atoms is the main structural feature on which ?1 depends. Within sets of all alkanes with a given number of carbon atoms the species (with and without quaternary carbons atoms) whose ?1-values are minimal and maximal are determined.
Study of sepiolite from Goles (Kosovo, Yugoslavia). II. Acid activation
Authors: Radojevic Marina , Jovic Vidojko , Karaulic Dragomir , Vitorovic Dragomir
Published: August 2005

The changes in the pore structure and adsorption properties of sepiolite from Goles resulting from treatment with 4MHCl for various periods of time were investigated. The BET method specific surface areas, pore volumes and f ? plots were determined by nitrogen adsorption. The surface area progressively increased during the 70 hours of acid treatment, when a maximum was attained. The differences in the adsorption properties of the original and the acid treated sepiolite were evaluated by comparison of adsorption isotherms obtained with benzene, n-hexane, methanol and isooctane. The enhanced adsorption of isooctane was of great interest, since the sorption of this compound on natural sepiolites is generally very limited. The results suggest that chemical treatment of sepiolite with 4MHCl for 70 h produces an adsorbent of optimal porosity and other adsorption properties.
Search for source rocks of the crude oils of the Drmno depression, southern part of the Pannonian Basin, Serbia
Authors: Jovancicevic Branimir , Wehner H. , Scheeder G. , Stojanovic K. , Sainovic Aleksandar , Cvetkovic Olga , Ercegovac Marko , Vitorovic Dragomir
Published: August 2005

In a search for source rocks of the crude oils of the Drmno depression (southern part of the Pannonian Basin, Serbia), based on bulk and specific organic geochemical parameters, six out of eight Sirakovo, Bubu{inac and Bradarac sedimentary core samples were found to possess typical source rock characteristics. By comparing the results observed for these sedimentary samples with the corresponding properties of the crude oils from the Sirakovo and Bradarac oil-gas fields, a positive organic geochemical oil-source rock correlation was experienced for the first time within this basin. This finding may be considered as an important step towards the ultimate organic geochemical/geological interpretation of the Drmno depression.
Radiochemical purity and particles number determinations of modified 99mTc-macroaggregated albumin
Authors: Djokic Divna , Jankovic Drina , Maksin Tatjana
Published: August 2005

Anew procedure for the aggregation of human albumin and 99mTc-labelling of the prepared macroaggregated albumin are presented. Simple methods for quantifying of all the radiochemical impurities existing in 99mTc-MAA were tested. Thus, 85% methanol was used as the mobile phase in paper and ITL chromatography with Whatman No 1 and ITLC-SAstrips. Asystem of two solvents (acetone and 1MNaCl or 0.9%NaCl) was used for 3MM paper, ITLC-SA and ITLC-SG strips and silica gel plates as the stationary phase. Low-voltage paper electrophoresis with Whatman 3MM paper sheets soaked in barbiturate buffer and the gel chromatography column method (Sephadex G-25) were also applied. Filtration through syringe filters, proposed by European and Yugoslav Pharmacopoeia, was performed for comparison. The application of the mentioned tests lead to consistent results for the labelling efficiency (> 98.5%) and percent radiochemical impurities of 99mTc-MAA. Determination of the particles number in a counter chamber and their size distribution under a light microscope with a calibrated ocular scale gave the result of 300000 ?350000 particles per 1 mg of HA. This confirmed that the human albumin macroaggregates prepared by our new procedure is remarkably improved and convenient for routine diagnostic purposes.
Coordination polymers of Fe(III) with ligands derived from dinaphthyl-, dinaphthylthio- and dinaphthyldithiophosphinic acids
Authors: Rosca Ioan , Sutiman Daniel , Vizitiu Mihaela , Sibiescu Doina , Cailean Adrian , Oprea Livia
Published: August 2005

The synthesis and the study of some coordination polymers derived from the interaction of the acetylacetonate of Fe(III) with dinaphthylphosphinic acid, dinaphthylthiophosphinic acid and dinaphthyldithiophosphinic acid are presented. The methods applied for the study were chemical analysis, gel chromatography, M?ssbauer and IR absorption spectroscopy, X-ray diffraction and thermogravimetric analysis from which the kinedic parameters of the thermal decomposition reactions were determined. The semiconductive properties of the synthesized compounds were also examined. Based on the obtained experimental data and on literature indications, the structural formulae of these compounds were assigned.
A kinetic method for the determination of phenol
Authors: Mitic Snezana , Zivanovic Valentina
Published: August 2005

Akinetic method for the determination of phenol is proposed. The method is based on the inhibiting effect of phenol on the Mn(II) catalysis of the oxidation of malachite green with potassium periodate. The reaction rate was followed spectrophotometrically at 615 nm. Kinetic expression for the reaction in the presence and absence of phenol are postulated. The optimal experimental conditions for the determination of phenol were established and phenol was determined in concentrations from 30.0 to 188.0 ng/cm3 with a relative standard deviation of 5.5%. The lower detecton limit is 7.8 ng/cm3. The effects of certain foreign ions upon the reaction rate were determined for the assessment of the selectivity of the method. The method was applied for the determination of phenol in tap and river water.
Monoazo disperse dyes based on 2-amino-1,3,4-thiadiazole derivatives
Authors: Maradiya Harir
Published: August 2005

A series of monoazo disperse dyes based on 2-amino-5-mercapto-1,3,4-thiadiazole was prepared by coupling with various N-arylmaleimides. The dyeing performance of these dyes was assessed on nylon fabric. The dyes were found to give yellow to brown colour shades on dyeing with good depth and levelness on nylon fabric. The dyebath exhaustion fixation and fastness properties of the dyes were also determined. The dyed fabric showed moderate to good light fastness and very good to excellent fastness to washing, rubbing, perspiration and sublimation. The IR and visible range spectral properties of the dyes were also determined.
Synthesis and application of novel heterocyclic dyes based on 11-amino-13H-acenaphtho[1,2-e]pyridazino[3,2-b]-quinazoline-13-one
Authors: Patel Vijay , Patel Manish , Patel Ranjan
Published: August 2005

A new fused heterocyclic compound, 11-amino-13H-acenaphtho[1,2-e]pyridazino [3,2-b]quinazolin-13-one was synthesized and used to prepare a novel series of heterocyclic mono azo dyes by coupling with various naphthols. All the mono azo dyes were characterized by their melting point, elemental analysis, UV-visible spectrum, infrared spectrum and dyeing performance on nylon and polyester fibres. The percentage dye bath exhaustion on different fibres was found to be reasonably good and acceptable. The dyed fibres show fair to good fastness to light and very good to excellent fastness to washing, rubbing, perspiration and sublimation.
The effect of solvent on the kinetics of the oxidation of benzaldehydes by quinolinium chlorochromate in aqueous organic solvent media
Authors: Jeyanthi Fatima , Vijayakiiinarand G. , Elango K.P.
Published: August 2005

The kinetics of the oxidation of benzaldehyde and para-substituted benzaldehydes by quinolinium chlorochromate in water-dimethylformamide mixtures has been studied under pseudo-first-order conditions at 25?0.2?C. The operation of non-specific and specific solvent-solute interactions was explored by correlating the rate data with solvent parameters through a correlation analysis technique. Both electron-releasing and electron-withdrawing substitutents enhance the rate of oxidation and the Hammett plot shows a break in the reactivity order indicating the applicability of a dual mechanism.
Insulin-induced glycosylphosphatidylinositol (GPI) binding to red cell membrane proteins
Authors: Tomasevic Nenad , Nikolic Milan , Niketic Vesna
Published: August 2005

In this work GPI binding to membrane proteins from erythrocytes of insulinoma patients for whom prolonged hyperinsulinism and hypoglycemia were characteristic, as well as from normal erythrocytes incubated with supraphysiological concentrations of insulin were analyzed. In the RBCs from insulinoma patients, covalent GPI binding to red cell membrane proteins in the spectrin/ankyrin region, band 4.1 and two proteins of molecular mass of 115 and 110 kD was demonstrated. In erythrocytes incubated with insulin label was associated with band 4.1 and two proteins of molecular mass of 115 and 110 kD. Extraction studies showed that the 100-kD proteins are unrelated to band 3 since they were found in Triton- prepared cytoskeleton. To our knowledge this is the first demonstration of such a modification of red cell skeletal proteins, and the first demonstration of post-translation GPI binding to red cell skeletal proteins in response to insulin. A mechanism proposed for GPI binding to red cell skeletal proteins as well as the relevance of these results for physiological disorders that are characterized by hyperinsulinism are briefly discussed.