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Introduction The gold standard for the determination of the erythrocyte sedimentation rate (ESR) is the Westergren method. Other methods to measure the ESR have become available. They range from modest modifications of the Westergren method to very different methodologies. The ICSH therefore established a Working Group to investigate these new approaches and compile recommendations for their validation and verification. Methods A panel of six experts in laboratory hematology examined the peer-reviewed literature and EQA surveys from over 6000 laboratories on four continents performing ESR testing. This information was used to create lists of ESR instrument manufacturers and their methods. Results Only 28% of laboratories surveyed used the unmodified Westergren method, while 72% of sites used modified or alternate methods. Results obtained with the new instruments could differ from results obtained with the Westergren method by up to 142%. Different non-Westergren methods showed differences from each other of up to 42%. The new methods were often significantly faster, safer, and less labor-intensive. They reduced costs and often used standard EDTA tubes, eliminating the need for a dedicated ESR tube. Conclusion Based on the consensus of the Working Group, recommendations for manufacturers for the validation of new ESR methods were developed. In addition, a list of recommendations for laboratories that are moving to modified or alternate methods was compiled, addressing instrument performance verification and communications of results to clinical users.

Gender is one of the factors that can influence the use of health resources. The use of tumour markers is widespread, due to the importance of these in monitoring cancer development. The aim of this study is to analyse the influence of gender on the use of tumour markers, and to investigate whether there are differences in their use.A longitudinal, retrospective and descriptive study, with a 2-year follow-up, was conducted in the catchment area of the University Hospital of Padua. An analysis was performed on 23,059 analytical requests for tumour markers. A descriptive and frequency analysis was performed on all variables. The statistical analysis was performed using Chi squared, Student t and Mann-Whitney U to test for significance.The number of requests for women (1.5) was lower than men (1.6). In patients with tumour pathology, the number of requests was higher than in patients without tumour disease. In the analysis by disease and gender, the difference remained significant. As regards the number of tumour markers per request, the difference between genders was also significant: 2.13 in males versus 2.85 in women. Similar results were obtained when requests for tumour markers linked to gender-related diseases were eliminated.There are differences in the use of tumour markers by gender with the number of requests for male patients being higher than for females. However, the number of tumour markers per request is greater in women than in men.

CNTs were prepared by CCVD and functionalized with inorganic acid, with the aim to study the effect of the surface properties on the catalytic performance in the selective alcohol oxidation using polar (water) and apolar (cyclohexane) solvent. The match between properties of the reactant and the solvent allows tuning the selectivity of the reaction.

As a result of incessant genetic discoveries and remarkable technological advancements, the availability and the consequent consumer's request for genetic testing are growing exponentially, leading to the development of a 'parallel' market, i.e. the direct-to-consumer (DTC) testing, also known as 'direct access testing' (DAT). Analogous to the traditional laboratory diagnostics, drawbacks of DTC testing might arise from any step characterising the total testing process, and include poor control of both appropriateness and preanalytical requirements, potential operation outside national or international regulation for in vitro diagnostic testing, little evidence of quality as well as the risk of transfer of genetic materials from the companies to other entities. Another important issue is the test panels offered to consumers, which are often based on preliminary, speculative or unsupported scientific information. Finally, the potential of this type of testing to generate anxiety or false reassurance should also be carefully considered. Although DTC testing carries some theoretical advantages (e.g. greater consumer autonomy and empowerment), solid clinical studies and costs vs. benefit analyses are needed to definitely establish whether DTC testing might be effective for decreasing the burden of diseases, delay their onset or modify their progression and therefore the clinical outcome.

Pepsinogens, precursors of pepsins (potent and abundant digestive enzymes that are the primary products of the gastric chief cells), are members of the family of aspartic proteases. Because of the heterogeneity of pepsinogens, several classifications have appeared in the literature. I describe the recommended classification and nomenclature of the aspartic proteases and discuss their genetics, biochemistry (structure, activation of zymogens, mechanism of proteolytic activity and inhibitors), and physiology. The focus will be on the zymogens of pepsin, the so-called pepsinogens. The measurement of these enzymes in serum is a reliable noninvasive biochemical method for evaluating peptic secretion and obtaining information on the gastric mucosal status. A detailed review of the methods for the measurement of pepsinogens in serum, urine, and gastric mucosa is also provided. Data on pepsinogen levels in healthy subjects are discussed with respect to sex, age, smoking habit, and the presence of a circadian rhythm. The value of pepsinogen measurements in peptic ulcer to determine ulcer outcome and recurrence, in gastric cancer, and in Helicobacter pylori infection is reviewed. Finally, the effects of drugs on peptic secretion are discussed. In light of these data, the measurement of aspartic proteases, and in particular that of pepsinogen A and C, may be regarded as an effective biochemical approach to the evaluation and monitoring of patients with upper gastrointestinal diseases.

Recent studies performing fiberoptic bronchoscopy in children have improved our understanding of asthma pathophysiology. Eosinophilic, but also neutrophilic, inflammation has been described in asthma, but the relationship with atopy was incompletely investigated. The aim of this study is to examine inflammatory cells and mediators in children with asthma compared to the appropriate controls, i.e. atopic children without asthma and children with no atopy or asthma. Moreover, asthmatic children were analysed separately based on the presence of atopy and stratified by age.We recruited 191 children undergoing fiberoptic bronchoscopy for appropriate indications: 91 asthmatics (aged 1.4-17 years), 44 atopics without asthma (1.6-17.8 years) and 56 nonasthmatic nonatopic controls (1.4-14 years). In bronchoalveolar lavage, total and differential cell counts and inflammatory mediators, including ECP, eotaxin, IL-8 and TNFalpha, were analysed.Eosinophils and ECP levels were increased in asthmatic children when compared to controls (P = 0.002 and P = 0.01, respectively), but also atopic children without asthma had increased ECP levels compared to controls (P = 0.0001). Among asthmatic children, eosinophils and ECP levels were not different between atopic and nonatopic individuals. Neither neutrophils nor the related mediators (IL-8 and TNFalpha) differed significantly in the three groups. This pattern of inflammation was observed in both preschool and school-aged asthmatic children.This study suggests that markers of eosinophilic, but not neutrophilic inflammation, are increased in asthmatic children and also in atopic children without asthma. Of interest, in asthmatic children, the activation of the eosinophilic response is not solely because of the presence of atopy.

The transition from quality assurance of the analytical phase to the quality management of total testing in clinical laboratories is still at an early stage. But it has begun. Accreditation through voluntary, educational and professional schemes, like the Clinical Pathology Accreditation scheme, is a useful tool for following defined standards of practice and having these independently confirmed on the basis of a peer review. Approved clinical laboratories can obtain a hallmark of performance and offer reassurance to users of their services. However, accreditation does not guarantee an error-free service; it is not the final step, but an important stage in the improvement process. Quality is a journey and continuous quality improvement is the paradigm for better addressing our efforts to satisfy customers' expectations for the desired health outcomes related to a high-quality laboratory service.

This review describes: 1. The main genetic alterations found in pancreatic cancer (EGF-R overexpression, SST-2 somatostatin receptor loss of expression, k-ras, p53 mutations and DPC4 mutations) and the effect of their replacements by gene therapy on tumor growth; 2. The use of suicide genes (HSV-TK and CD) for pancreatic cancer gene therapy in vitro and in vivo; 3. The implications for pancreatic cancer treatment when using cytotoxic bacterial toxins; 4. Viral and non-viral delivery systems for the transfer of therapeutical genes into pancreatic cancer cells. Overall both the correction of pancreatic cancer cells main genetic alterations and the use of suicide genes allow only partial tumor regression in vitro and in vivo. The lack of a 100% effect for any studied strategy considered alone, indicates the need for combined therapies to achieve a satisfactory treatment of this tumor.

Skeletal muscle disorders may result in release of muscle enzymes into the circulation and give increased serum enzyme activity. A variety of enzymes routinely determined in the clinical laboratory may be elevated, but creatine kinase is the enzyme present in the highest concentration in muscle, and in every variety of muscle disease is the serum enzyme which shows the greatest incidence and degree of elevation. Aspartate aminotransferase is the enzyme associated most significantly with inflammation. A diagnostic algorithm based on the combined measurement of creatine kinase, aspartate aminotransferase and aldolase has been found to discriminate muscular distrophies from polymyositis and other myopathies. This combination of laboratory tests has diagnostic application and thus allows the clinician to better select patients who need to have a skeletal muscle biopsy as a diagnostic procedure.

Helicobacter pylori infection outcome might depend on genotypic polymorphisms of both the bacterium and the host. We ascertained: (1) the functionality of H. pylori oipA gene; (2) the polymorphism of the hostinterleukin (IL-1beta) gene (-31 C/T) and of the IL-1RN gene (intron 2 VNTR); (3) the association between the above genes and the histological and pathological outcome of H. pylori infection. One hundred and sixty-five H. pylori positive and 137 H. pylori negative subjects (23 gastric adenocarcinoma, 58 peptic ulcer, 221 gastritis) were studied. oipA was sequenced, IL-1beta was RFLP analysed. Antral and body mucosal biopsies were histologically evaluated. Functional oipA genes were correlated with cagA gene; both genes were significantly associated with gastritis activity, peptic ulcer and gastric adenocarcinoma. In these patients heterozygousIL-1RN 1/2 and IL-1beta C/T genotypes were more frequent than in gastritis patients. Intestinal metaplasia was associated with cagA, functional oipA and IL-1RN 2 allele. In conclusion, peptic ulcer and the preneoplastic intestinal metaplasia are associated with H. pylori virulence genes and with IL-1RN 2 host allele. An interplay between bacterial virulence factors and cytokines genotypes, is probably the main route causing H. pylori infection to lead to benign mild disease, benign severe disease or preneoplastic lesions.

To study the extracellular composition of giant papillae in vernal keratoconjunctivitis (VKC) and the expression of growth factors that may stimulate fibrosis.Upper conjunctival specimens were obtained by biopsy in 9 patients affected by active tarsal VKC (14 eyes) and 10 normal control subjects. Immunohistochemistry was performed on tissue sections using monoclonal antibodies (mAbs) for collagens I, III, and VII; tumor necrosis factor (TNF)-alpha; transforming growth factor (TGF)-ss1; basic fibroblast growth factor (bFGF); and platelet-derived growth factor (PDGF). The mAbs anti-tryptase, anti-CD4, anti-CD68, and anti-EG2 were used as markers for mast cells, T-helper lymphocytes, macrophages, and eosinophils, respectively. Immunofluorescent double-staining for growth factors and cell markers was performed in VKC tissues.Immunostaining was highly positive for collagens I, III, and VII in the subepithelium of VKC conjunctiva. Image analysis showed a significant increase of staining per tissue area for both collagens I and VII and increased basal membrane length. The number of cells positive for TNF-alpha, TGF-ss, bFGF, or PDGF was significantly higher in VKC tissue than in control samples. Double staining showed that eosinophils and macrophages were the main sources of PDGF and that FGF was expressed by 46% of mast cells. Significant PDGF and FGF staining was observed in the conjunctival epithelium and vascular endothelium of all VKC tissues.In giant papillae of VKC, the extracellular matrix is characterized by overproduction of collagens. Expression of growth factors in the conjunctiva by resident cells (mast cells, epithelial cells, endothelial cells) and inflammatory cells (macrophages, eosinophils) may contribute to papillae formation and fibrosis evolution in chronic ocular allergic diseases.

In this study, we examine C-reactive protein (CRP) and serum amyloid protein A (SAA). Although the former is the best known and most commonly used indicator of inflammation, certain considerations underline the inadequacy of CRP determination alone for the early diagnosis of infection. In fact symptoms often precede the CRP elevation. SAA protein comprises a family of polymorphic apolipoproteins produced mainly by the liver, and several studies have stressed its importance in the diagnosis and monitoring of various diseases. Pathological SAA values are often detected in association with normal CRP concentrations. SAA rises earlier and more sharply than CRP. Finally, contrary to CRP, SAA presents the same trend in viral as well as bacterial infections. Although the data available on SAA in neonates are currently very limited, it is possible to postulate a role of primary importance for SAA in the management of neonatal infections.

Interlaboratory surveys on urine quantities have only recently been introduced in several European countries. Representatives of 10 European countries exchanged their experiences during an international urinalysis meeting held in September 1999. Although still not mandatory in most areas, more than 5000 laboratories participated in external quality assessment programs in the countries represented. Qualitative (test strips and microscopic morphology) as well as quantitative chemical and immunochemical quantities were included. The maximal allowable deviations are reported as well as methods used to determine target values. Consensus scales up to reference methods were applied. The participants agreed that quality criteria need to be defined separate from those already existing for plasma/serum analytes. Besides higher biological variables and different medical needs, less standardisation of methods to quantify urine constituents was observed as a major cause of higher interlaboratory differences.

Percent free prostate-specific antigen (PSA) is a promising tool for prostate cancer (CaP) diagnosis. However, its diagnostic performances have not yet been established. The present study was carried out with the aim of evaluating percent free PSA in the most favourable analytical conditions.Eighty-eight patients affected by newly diagnosed, untreated, primary CaP, and 169 cases with biopsy-confirmed, untreated, benign prostatic hypertrophy (BPH) were prospectively enrolled. Abbott AxSYM total and free PSA were measured by the same technician using the same instrument and the same reagent batch.Percent free PSA was more effective than total PSA in differential diagnosis between CaP and BPH in every evaluated dose range of total PSA. In cases with total PSA4 microg/l, percent free PSA could have reduced by about 50% the rate of unnecessary biopsies with a probably still acceptable 93% cancer detection rate. The likelihood of CaP after the determination of percent free PSA was in fact higher than 50% using cut-off points which provide low sensitivity values (i.e. 58% in men aged 50-59 years).Percent free PSA is superior to total PSA in distinguishing primary CaP from BPH in patients with total PSA between 2 and 30 microg/l and in reducing the rate of unnecessary biopsies in men with total PSA higher than 4 microg/l. However, percent free PSA should be cautiously interpreted in decision making in individual patients since post-test probability is relatively low in men aged 50-70 years.

Many medical laboratories have made a start with the introduction of quality management systems. However, it is still not clear against which standards such systems should be measured. The existing ISO and CEN standards do not cover essential aspects of medical laboratories. The publication of the EC4 Essential Criteria has stimulated the development of the ISO/Draft International Standard 15189. This standard seems adequate for our type of laboratories. However, it is not easy to read. The EC4 Essential Criteria could well serve as a guide, covering additional aspects, e.g. on total quality management and budget management as required in the EFQM model, that are not (yet) included in the ISO standard. In the present article the EC4 Essential Criteria are cross-referenced with two new international ISO standards, ISO/FDIS 15189 and ISO/FDIS 17025, the latter being the successor of ISO guide 25 and EN 45000. Both new ISO documents are in compliance with the new ISO 9000:2000 standard.

Few studies have shown a significant increase of CD3+ T-cell receptor (TCR) gamma delta in the early phases of type 1 diabetes. We wished to determine if CD3+ TCR gamma delta is involved in the pathogenesis of gestational diabetes mellitus (GDM). We studied 29 GDM patients and 21 normal pregnant women. Lymphocyte subpopulations (CD3+ TCR alpha beta, CD3+ TCR gamma delta), islet cell antibodies (ICA), glutamic acid decarboxylase antibodies (GAD) and protein tyrosine phosphatase antibodies (IA2-Ab) were evaluated in all patients. The percentage of CD3+ TCR gamma delta was significantly higher in GDM women than in the control group (5.1 +/- 2.9% vs 3.7 +/- 1.7%; p0.05). No abnormalities of the other lymphocyte subpopulations were found. All subjects were negative for ICA; 2 GDM patients were positive for GAD, but no relationship was found between GAD positivity and CD3+ gamma delta levels in these 2 patients. Further follow-up studies of these patients are required to verify if the CD3+ TCR gamma delta receptor is a useful marker for diabetes development.

Th2 lymphocytes may play a key role in the development of allergic diseases such as vernal keratoconjunctivitis (VKC). Cytokine flow cytometry of tear samples was used to identify the phenotypical and functional properties of lymphocytes at the actual site of the allergic reaction.Tear and blood samples were obtained from patients affected by active VKC (n = 12) and from normal control subjects (n = 10). Tears were obtained after gentle scraping of the tarsal and bulbar conjunctiva. Tear and blood samples were placed in a solution of brefeldin-A, phorbol myristate acetate (PMA), ionomycin, and RPMI for 4 hours and then processed for flow cytometry. Lymphocytes were marked with the monoclonal antibodies, anti-IFN-gamma and anti-interleukin (IL)-4. Levels of IL-4, IL-2, IFN-gamma, IL-2R, total IgE, eosinophil cationic protein (ECP), eosinophil protein X/neurotoxin (EPX), and myeloperoxidase (MPO) were also evaluated in serum.Expression of IL-4 was observed in 9.2%+/-9.5% of lymphocytes in tears of patients with VKC. Of the 12 patients with VKC, 8 (67%) had tear lymphocytes positive for IL-4 (Th2). Two patients (17%) had a double population of lymphocytes: One was positive for Th2, and the other was positive for both IL-4 and IFN-gamma (Th0). One patient (8%) was positive for IFN-gamma (Th1) only, and one patient was negative for both ILs. No differences in the percentage of Th2 lymphocytes were found between tarsal and limbal patients. The percentage of Th2 lymphocytes was significantly correlated with the severity of the disease. No positive lymphocytes were found in tears of control subjects. Eosinophils, serum IgE, ECP, and EPX were all significantly higher in VKC than in control subjects.In ocular allergic diseases, local lymphocytes expressed the Th2 phenotype and, to a lesser degree, the Th0 phenotype. Although results of systemic allergic markers can be inconclusive in patients with VKC, flow cytometry demonstrated a local lymphocyte phenotype that can account for the clinical and histologic abnormalities of VKC.

The serum determination of pepsinogen A (PGA) and pepsinogen C (PGC) might indicate gastric mucosal inflammation and atrophy. Body gastric mucosa produces both PGA and PGC, while antral mucosa produces only PGC. Therefore, diseases involving mainly the antrum, such as H. pylori infection, are mainly indicated by the variations in serum PGC than in serum PGA. In agreement, when the antral mucosa is infected by the more virulent cagA positive H. pylori strains, which cause severe inflammation, serum PGC significantly increases. Another indirect indicator of gastric inflammation is polymorphonuclear (PMN) oxidative burst after the stimulation with water extracts from H. pylori culture: this parameter is significantly increased in infected if compared to non-infected subjects. The higher oxidative burst response of peripheral PMN in infected patients, possibly consequent to the release of specific cytokines able to prime PMN towards H. pylori products, is unable to eliminate the infection, but it might concur in damaging the gastric mucosa.

Determination of myoglobin, a low molecular weight haeme protein (17.8 kDa), present in both cardiac and skeletal muscle, is an old test with new perspectives. Advantages and disadvantages of myoglobin determination are well known; recent availability of rapid and accurate methods for the assay of this protein has greatly enhanced interest in the clinical utilization of the test. However, since myoglobin is present in both skeletal and cardiac muscle, any damage to these muscle types results in its release in blood and, consequently, high levels of the protein are observed in conditions unrelated to acute myocardial infarction (AMI). New strategies for myoglobin measurement may resolve this limitation. These strategies include both the combined measurement of myoglobin and a skeletal specific marker (carbonic anhydrase III) or a cardiac specific marker (troponin I or T), as well as myoglobin evaluation on serial samples. In particular. the diagnostic algorithm based on combined measurement of myoglobin and troponins significantly improves diagnostic efficiency in laboratory assessment of suspected AMI patients. However, further efforts are necessary to improve the standardization of present methods for myoglobin measurement: the significant disagreement demonstrated between some commercially available assays should be carefully considered in clinical practice.

It has been suggested that transforming growth factor beta (TGFb) mediates liver fibrosis, which can be monitored by the serum determination of the N-terminal peptide of type III procollagen (PIIIP) and laminin. Fibrosis is also an important phenomenon in patients with chronic pancreatitis (CP). In 23 patients with CP, 38 with liver cirrhosis (LC) and 20 healthy controls we compared the serum patterns of PIIIP, laminin and TGFb and assessed whether in CP these markers are correlated with exocrine and endocrine function. In patients with LC, PIIIP and laminin levels were significantly higher, whereas TGFb levels were significantly lower than those of controls. In CP patients, no significant variations were found for PIIIP and laminin, although levels were high in 7/23 and in 5/23 patients, respectively. TGFb levels in CP patients were higher than those in LC patients, levels being raised in 6/23 patients. In LC patients an inverse correlation was found between PIIIP and TGFb, whereas in CP patients, a direct correlation was found between TGFb and PIIIP. Moreover, in CP patients, there was also a positive correlation between TGFb and fasting serum glucose levels, while laminin was correlated with PABA test results.serum biochemical markers of liver fibrosis can be considered of limited value in assessing pancreatic fibrosis; in liver cirrhosis there may be a negative feed-back regulation between TGFb production and the fibrogenetic process; and in chronic pancreatitis TGFb appears to favor fibrosis on the one hand and the development of hyperglycemia on the other.

The study reports the analytical and diagnostic performances of Cell Dyn 3500 (Abbott), an automated haematology analyser that provides the electrical impedance and the optical detection of total leukocyte and a five population leukocyte differential count. The evaluation of complete blood count and differential leukocyte count parameters was performed following the guidelines of the International Council for Standardization in Haematology and those of the National Committee for Clinical Laboratory Standards document H20-A.The CD 3500 demonstrated a good linearity, minimal carry-over, as well as acceptable levels of within and between-batch imprecision and stability. An excellent correlation between CD 3500 and the routine systems used in our laboratory (Technicon H*2 and Coulter STKS) was found for the major haematological indices, though agreement was not as good for MCHC. There was a good correlation between CD 3500 and manual reference differential method for neutrophils, lymphocytes, eosinophils and basophils, with the exception of monocytes.Regarding clinical sensitivity, the CD 3500 showed a high specificity to detect morphological abnormalities, but low sensitivity especially for the identification of immature granulocytes and nucleated red blood cells; if we overall evaluate any qualitative flags, we found an appreciable increase in sensitivity.

Cord blood IgE levels have been studied as a possible marker of allergy in infants but few studies are available in our Region. The aim of this paper was to test IgE levels in cord blood of 60 consecutive newborns in a restricted area of Veneto, to correlate cord blood IgE levels with family history of allergy and to verify the risk of contamination from mother's blood.Cord blood was obtained from 60 consecutive newborns. Immunoglobulin levels (IgG, IgA, IgM, and IgE) were measured in cord blood of newborns and in serum of all mothers. Family history for allergy was previously investigated from the mothers.IgE were detectable in cord blood of 5 newborns but only 2 of them had positive family history for allergy which was pointed out in 11/60. In one of these cases the contamination of sample from mother's blood was postulated. IgG levels in newborn cord blood were higher than in mothers' blood and it was not related with IgE levels or other investigated factors.Only 6.6% of newborns in a restricted area of Veneto region have detectable IgE in cord blood whereas 18.3% of them have positive family history for allergy. Measurable levels of IgE in cord blood are not related with positive family history of allergy and are rarely influenced by mothers' blood contamination.

The urokinase-type plasminogen activator (UPA) and its inhibitor PAI-1 are thought to play an important part in gastric cancer (GC) invasion and metastasis. Little is known about the behavior and prognostic impact of the receptor for UPA (UPAR). The aims of the present study were: (1) to measure UPAR, UPA and PAI-1 levels in GC and in non-malignant tissue distant from the tumor (NORM); (2) to evaluate their relationship with histomorphological parameters; and (3) to determine their prognostic value. UPAR, UPA and PAI-1 levels were determined by ELISA in GC and NORM samples from 20 patients with GC undergoing surgery. The GC was also examined in terms of the presence (n = 10) or absence (n = 10) of metastasis, differentiation (five differentiated, 15 undifferentiated) and histotype. Survival was analysed using life table analysis. UPAR, UPA and PAI-1 were significantly higher in GC vs NORM, in the presence of metastasis (UPAR, UPA) and in undifferentiated GC (UPAR, PAI-1). UPAR significantly correlated with UPA and PAI-1. Low levels of UPAR (P = 0.04), UPA (P = 0.007) and PAI-1 (P = 0.02) were associated with a better survival. Our results demonstrate a sharp increase in UPAR in GC and suggest a prognostic role for it. The concomitant activation of UPAR, UPA and PAI-1 in GC confirm the important role of the plasminogen activator system in the process of invasion and metastasis.

Cathepsin B and L (cysteine proteases), urokinase- and tissue-type plasminogen activators (serine proteases), and type-1 inhibitor are involved in gastric mucosal injury. We determined tissue protease levels in duodenal ulcer and their relationship to ulcer phase, bleeding tendency, Helicobacter pylori infection, and use of H2-blockers.Endoscopic biopsies of antral and duodenal mucosa were obtained from 61 patients with active or healed duodenal ulcer and control subjects. Antigen concentrations were measured by ELISA.Significantly higher levels of cathepsins, urokinase-type plasminogen activator, type-1 inhibitor, and significantly lower levels of tissue-type plasminogen activator were found in active ulcers. Bleeders had the highest cathepsins and urokinase-type plasminogen activator levels. Higher levels of urokinase-type plasminogen activator, cathepsin B, and type-1 inhibitor were observed in Helicobacter pylori-positive patients.Our results suggest that impaired fibrinolysis (tissue-type plasminogen activator), intramucosal proteases (cathepsins), tissue remodeling, and angiogenesis (urokinase-type plasminogen activator and type-1 inhibitor) are involved in duodenal ulcer formation and healing.

We studied the analytical and clinical efficiency of a "second generation" technique for the in vitro determination of specific IgE, the so-called CARLA system (Capture Assay Radim Liquid Allergen). Reproducibility studies demonstrated satisfactory intra- and inter-assay analytical imprecision. The linearity test gave good results, and no significant interference by non-specific total IgE was found. The diagnostic efficiency of the system for the five most representative aeroallergens (D1, Dermatophagoides pteronyssinus; E1, Cat's epithelium; G5, Lolium perenne; W19, Parietaria officinalis and W5, Arthemisia absinthium) was evaluated using the Receiver Operating Characteristic (ROC) analysis in eighty-nine patients with suspected inhalant allergies. For each aeroallergen the area under the ROC curve and the most efficient threshold were calculated. Satisfactory areas under the ROC curve were found for D1, G5, E1 and W19, while a lower diagnostic efficiency was observed for W5. The most efficient thresholds differed from one allergen to another, although the differences were not great.

During cancer monitoring, data on biological and analytical variation are required in order to define the critical difference which provides an objective means to interpret serial values. We evaluated four tumor markers on serial samples collected from healthy subjects and patients. Analytical coefficients of variation (CV(A)), were obtained from "precision profiles" based on the differences between duplicates cumulated from assay runs in the laboratory. We defined the mean intrasubject biological variation (CV(I)) for CA 19-9 and TPA, separately for healthy people and patients; since the differences between the two groups were not statistically significant, we pooled the results and re-evaluated CV(I) in the combined groups (CA 19-9: CV(I) = 15.9%; TPA: CV(I) = 25.7%). In addition, we evaluated CV(I) for CEA (10.9%) and for TPS (25.9%) in patients. We then evaluated the inter-subject biological variations (CV(G)); the calculated indices of individuality for the four markers were less than 0.6 which shows conventional reference values to be of little utility for interpretation. We finally evaluated the critical differences (p0.05) for CA 19-9 (CD = 44.7%), for TPA (CD = 72.5%), CEA (CD = 32.7%) and TPS (CD = 72.5%); these are generally applicable since there was no heterogeneity in intra-subject biological variability.

In this study we evaluated the analytical performances of the Cell Dyn 3500, an automated hematology analyzer that provides the electronic and optical detection of leukocyte count and the complete cell counts in samples of whole blood. The protocol included evaluation of complete blood count and differential leukocyte count parameters, using the ICSH and the NCCLS H20-A protocols. Technical performances with regards, to linearity, carry over, precision and stability were quite well acceptable; the accuracy showed a good agreement between Cell Dyn 3500 and instruments used in our laboratory for the major hematologic indices and a good correlation for neutrophils, lymphocytes and eosinophils compared with the manual count.

Controversial data have been obtained with direct cellular protection by prostaglandins and sulfhydryls. In the present studies, we compared the merits and liabilities of currently available cell viability assays, some of which have not been previously employed in studies of the gastric mucosa. We also tested the hypothesis that length of incubation of isolated cells with protective agents might influence the degree of cellular damage. Gastric mucosal cells were isolated from nonfasted rats and digested with various concentrations of pronase and/or EGTA. Cell viability was assessed by trypan blue and fast green exclusion, fluorescein diacetate hydrolysis, chromium release, LDH release, mitochondrial succinate dehydrogenase activity and nuclear fluorescence induced by ethidium bromide. The experiments revealed that both pronase and EGTA are needed to obtain mucosal cells with optimal yield and initial viability and that sequential additions of pronase (30 min) and EGTA (30 min), rather than their combination (60 min), increased viability without decreasing yield. Cell viability and yield were better when pronase was used in the first incubation. For LD50 determinations, a cell suspension was incubated with ethanol (0%-15%) for 5 min. For studying the effects of protective agents, the cells were pretreated with 16,16-dmPGE2 or cysteamine HCl at 37 degrees C for 30 min before a 5-min exposure to 7.5% or 15% ethanol. The LD50 value for ethanol injury was approximately 15% for all assays except LDH, where the LD50 value was 8.5%. Preincubating gastric mucosal cells for 30 min with 16,16-dmPGE2 or cysteamine resulted in no preservation of cell viability. However, when cells were preincubated with one of the protective agents for 60 min and then exposed to 8% or 10% ethanol for 5 min, partial protection was observed when assessed by succinate dehydrogenase activity and, in certain cases, by LDH release. We conclude that all seven cell viability assays yield a measurable LD50 value for ethanol-induced cell injury, but the results may vary by as much as 82%. Low concentrations of both pronase and EGTA are needed to obtain isolated mucosal cells with both high yield and initial viability. Biochemical measures of mitochondrial activity and nuclear damage provide reliable evidence of cell viability and should be used to complement membrane permeability assays. Long preincubation of cells (60 min) with protective agents resulted in only slight protection of mitochondrial function, in contrast to the rapid induction of gastroprotection seen with these compounds in vivo. We therefore surmise that processes that contribute to organ protection occur faster and more efficiently than those that control direct cell injury and protection.

Polymorphonuclear neutrophils play an important role against pathogens through the production of toxic oxygen metabolites by the NADPH oxidase enzyme, which reduces oxygen to superoxide anion in the respiratory burst. Neutropenia, infectious complications and impaired neutrophil function are often reported in glycogen storage disease type Ib (GSDIb), a metabolic disorder characterized by increased glycogen and decreased glucose-6-phosphatase (G-6-P) activity in the liver. Two children with GSDIb and associated neutropenia with recurrent bacterial infections were treated daily with different doses of rHu-GM-CSF. NADPH oxidase activity and chemotaxis in patients were assessed before and during therapy in stimulated and unstimulated neutrophils. During rHu-GM-CSF treatment, any increase found in the NADPH oxidase activity of patients was not significant with respect to that in controls. In one patient chemotaxis was greater than of controls. This finding suggests that in patients with GSDIb both neutropenia and PMN abnormalities may be responsible for infections, and PMN dysfunction probably depends on the degree of inherited functional G-6-P deficit.

Laboratory medicine is at a crossroads that provides great opportunities to improve the efficacy of the service and its role in healthcare. Many of the new roles for laboratory staff will be outside the boundaries of the traditional laboratory. These roles include increased emphasis on consultative activities, participation in interdisciplinary teams, and efforts to assure appropriate test utilization. Audit in laboratory medicine may be defined as a process of review and assessment of laboratory performance, and its purpose should be to improve patient care by enhancing laboratory performance and making better use of resources. Here we discuss the rationale of audit in laboratory medicine, its goals as well as its topics. The suggested conduct for an audit and the involvement of personnel are also reviewed.

Helicobacter pylori (Hp) infection is known to cause several gastroduodenal diseases. In patients with non-ulcer dyspepsia, we assessed the link between Hp infection and gastric mucosal inflammation, as well as the influence of Hp and inflammation on the serum levels of anti-Hp antibodies (IgG), pepsinogen A (PGA), pepsinogen C (PGC), and gastrin.Entering the study were 221 patients with non-ulcer dyspepsia, all of whom underwent upper gastrointestinal endoscopy.Of the 221 patients investigated, 135 (61%) were Hp positive. The higher the bacterial load, the worse the associated gastritis, the gastric antrum and body being considered. All of the serological indices studied were found to be influenced by gastritis. Serum IgG satisfactorily discriminated between Hp-positive and Hp-negative subjects, with a sensitivity of 84% and a specificity of 86%. PGC, PGA, and gastrin were less accurate. Only PGC only found to be correlated with Hp load. The product of IgG and PGC improved the diagnostic accuracy of IgG alone.Hp infection, frequently found in patients with non-ulcer dyspepsia, is associated with gastric mucosal inflammation; of the indices studied, serum IgG and PGC most accurately indicated Hp infection, and their product may be proposed as an aid in diagnosing Hp infection in dyspeptic patients.

Cysteine proteases (cathepsin B [CATB] and cathepsin L [CATL]), the serine protease urokinase-type plasminogen activator (UPA), and plasminogen activator inhibitor type-1 (PAI-1) are thought to play an important part in cancer invasion and metastasis. The aims of this study were to measure CATB, CATL, UPA, and PAI-1 in gastric cancer (GC) and normal mucosa distant from the tumor (NORM); to evaluate whether tissue levels are related to tumor stage, grade, or histotype; to assess their prognostic relevance; and to examine UPA and PAI-1 expression immunohistochemically.Gastric cancer and NORM samples were obtained from 25 patients with gastric cancer patients undergoing surgery (17 males, 8 females; mean age, 62 years; range, 31-84 years). Antigen concentrations were measured using the enzyme-linked immunosorbent assay method. Immunohistochemistry was performed using monoclonal UPA and PAI-1 antibodies.Significantly higher antigen levels were found: (1) in GC vs. NORM (CATB, CATL, UPA, PAI-1) tissues; (2) in GC with versus without metastasis (CATB, CATL, UPA); (3) in poorly or moderately versus well differentiated GC; and (4) in diffuse versus intestinal-type GC (CATB, CATL). Urokinase-type plasminogen activator, PAI-1 and CATB levels had a significant prognostic impact. Cancer and stromal cells, showed immunoreactivity to anti-UPA and anti-PAI-1 antibodies.These results confirm the important role of CATB, CATL, UPA and PAI-1 in gastric cancer progression. Higher levels are detected in GC with metastases, poorer differentiation, and diffuse histotype, thus identifying patients with a worse prognosis.

This report describes the findings of an evaluation of the validity of the new, highly automated Serono SR1 enzyme immunoassay for prostate specific antigen performed at three European sites. Within-run precision was below 5.5% at the clinically important decision point of 4 micrograms/l, less than 10% below 3 micrograms/l and less than 5% above 4 micrograms/l. Between-run precision was below 12% at each site and between-site precision was less than 14%. Dilution series were shown to be parallel to the standard curve on 12 samples with neat prostate specific antigen concentrations ranging from 20 to 88 micrograms/l (linear regression slopes and correlation coefficients of 1.00 to 1.06 and 0.972 to 1.000 respectively). Comparisons with Hybritech Tandem-E and -R and Roche Cobas Core prostate specific antigen methods used routinely at the three sites were good (linear regression slopes 1.04 to 1.13, correlation coefficients 0.96 to 0.99), but results were significantly lower than the Ciba Corning ACS180 (slope 0.66, correlation coefficient 0.99). The assay presents a precise, robust and valid diagnostic tool offering additional advantages of non-isotope automation.

Specific serum IgE determination is widely used in the diagnosis of IgE-mediated allergic diseases but the relative merits of in vitro measurement of IgE antibody in comparison to in vivo skin tests are still debated.The aim of this study was to investigate the clinical efficiency of a "second generation" technique for in vitro analysis of IgE antibody (Pharmacia CAP System).Eighty-six patients with suspected inhalant and/or food allergies and 20 asymptomatic subjects for a total of 655 tests were evaluated. Sera with divergent results between in vitro and in vivo techniques were further analyzed by using ImmunoCAP inhibition and immunoblotting. For the calculation of sensitivity and specificity of both in vitro and in vivo tests we considered as true value (reference value) either the concordant results or, in case of discordance, the datum confirmed by ImmunoCAP inhibition or immunoblot (ie, vitro positive, vivo negative, ImmunoCAP inhibition positive; true result: positive).The obtained results demonstrate that the in vitro results correlate well in terms of specificity and sensitivity to this new reference standard. In particular a higher specificity for Pharmacia CAP System in comparison to in vivo skin prick test for grass pollens and a better sensitivity for mites and cat allergens were found.Our results suggest that the in vitro "second generation" testing provides reliable results in all clinical situations.

Recently, a new immunometric assay (Cyfra 21–1) was developed to measure serum concentrations of a soluble fragment of cytokeratin subunit 19. With this method, supplied by Boehringer Mannheim (EIA Test Cyfra 21–1), an Italian multicenter trial was performed in patients with lung cancer. Cyfra 21–1 serum levels were determined in 568 normal subjects (blood donors), 607 patients with non-malignant diseases (491 respiratory diseases) and 730 patients with malignancies. In the latter group 584 had lung cancer. All these 584 patients had pathologically confirmed disease; 314 were epidermoid tumors, 166 adenocarcinomas, 88 small cell cancers and 16 large cell cancers. In the 568 healthy blood donors the mean Cyfra 21–1 value was 0.91 ng/ml (SD 0.47 ng/ml; range 0.05–2.90 ng/ml). A threshold of 1.9 ng/ml was chosen as the upper limit of normality. High levels of Cyfra21–1 were observed in patients with chronic hepatitis (positivity rate: 17/51–33.3%) and with pancreatitis (positivity rate 5/16 - 31.3%). In 114 out of 491 (23.2%) patients with respiratory diseases Cyfra 21–1 showed values greater than 1.9 ng/ml. The overall sensitivity (all stages) of Cyfra 21–1 in lung cancer was 65.6% (383/584). When the histology was considered the highest positivity rates were found in patients with squamous cell tumors (226/314; 72%) followed by adenocarcinomas (105/166; 63%). In patients with SCLC the global sensitivity was 52.3% (46/88). Higher sensitivity of Cyfra 21–1 was observed from stage I to stage IV (53.9% vs 85.7%; Chisquare: p < 0.01). When comparing patients in whom curative resections were possible (up to stage IIIa) with patients suffering from inoperable tumors, a significant difference in Cyfra 21–1 positivies was found (59% vs 81.5%; Chi square p < 0.01).