PubMed Health⌕ Search

Biomedical subjects

C Saltini

Publications and source records attributed to C Saltini.

At least 37 records · Page 2Linked to original sources
PubMed2000

Evaluation of a western blot test as a potential screening tool for occupational exposure to Mycobacterium tuberculosis in health care workers.

Health care workers (HCWs) have a higher than average risk for contracting Mycobacterium tuberculosis (MTB) infection and tuberculosis (TB). No markers of MTB-exposure are available, and TB risk assessment is performed by tuberculin screening, identifying individuals with acquired MTB infection. This study evaluated a western blot (WB) anti-M. bovis A60 complex antibody as a MTB-exposure marker. WB reactivity was evaluated on 127 exposed and 28 non-exposed HCWs from four divisions of the Policlinico Hospital of Modena, and 140 non-exposed bacille Calmette-Guérin-vaccinated controls. Excess of occupational TB risk according to the Occupational Safety and Health Administration (OSHA) was calculated in each division. WB-positivity (%) was: (1) significantly higher in exposed HCWs compared with non-exposed (72% vs 25%, P < 0.00001), (2) highly related (r = 0.99) to OSHA risk excess in all divisions, (3) higher than non-exposed in HCWs with short (< 5 years) MTB-exposure (purified protein derivative [PPD], P > 0.18; WB, P < 0.04). PPD-positivity (%) was higher than controls only in HCWs with longer (> 5 years) MTB-exposure. The study suggests that the WB antibody might represent a more sensitive biological marker of MTB contact among exposed HCWs, related to the level of TB risk and detectable earlier than the PPD skin test, thus providing new tools for TB risk assessment in health care facilities.

Adult↗
PubMed2000

Surveillance of anti-tuberculosis drug resistance: results of the 1998/1999 proficiency testing in Italy. SMIRA (Italian Multicentre Study on Antituberculosis Drug Resistance) Study Group.

OBJECTIVE: To determine the accuracy of drug-susceptibility testing (DST) for isoniazid, rifampicin, ethambutol and streptomycin in a provisional network of 22 regional laboratories in Italy. METHODS: Methods, definitions and reference Mycobacterium tuberculosis strains were derived from the WHO/IUATLD Global Project on Anti-tuberculosis Drug Resistance Surveillance. The laboratories were selected based on technical skills required by the project, the number of DST performed annually and geographic localisation. The results (sensitive/resistant strain) were compared with the gold standard (global project results). Sensitivity (ability to detect true resistance), specificity (ability to detect true susceptibility), positive predictive values for resistance and susceptibility, efficiency and reproducibility were calculated in two rounds. RESULTS: Eighteen of 22 laboratories completed the first round of proficiency testing for the four drugs. Sensitivity was 76.6%, specificity 97.2%, predictive value of a resistant test 89.8% and of a susceptible test 86.8%, efficiency 87.8% and reproducibility 92.8%. A second round was performed by all those laboratories that did not achieve > or = 90% agreement with the results of the Global Project. Overall, after the second round, all the parameters except specificity improved, exceeding 90%. CONCLUSIONS: A network of 15 regional laboratories that fulfil the quality criteria for determining the susceptibility of M. tuberculosis to the four primary antituberculosis drugs was established in Italy.

Antitubercular Agents↗
PubMed1999

Sensitivity and specificity of a multi-antigen ELISA test for the serological diagnosis of tuberculosis.

A new serological assay (DETECT-TB, BioChem ImmunoSystems), using three recombinant proteins and two synthetic peptides for the detection of the anti-Mycobacterium tuberculosis IgG, was evaluated using a panel of serum specimens collected from 100 tuberculosis (TB) patients and 270 controls, in comparison with a homemade ELISA test using purified protein derivative (PPD) as antigen. DETECT-TB presented a higher sensitivity (75%) compared to PPD-ELISA (56%; P < 0.01), while the specificity of each assay was similar (DETECT-TB 97%; PPD-ELISA 100%; P > 0.80). Receiver operating characteristics (ROC) analysis obtained with these data confirmed the higher level of performance of DETECT-TB in comparison with PPD-ELISA. Considering the rapidity, cost-effectiveness and simplicity of this assay, its use may provide useful clinical information aiding in the rapid diagnosis of difficult TB cases.

Adult↗
PubMed1998

Alpha 1-antitrypsin nonsense mutation associated with a retained truncated protein and reduced mRNA.

alpha 1-Antitrypsin (alpha 1AT) provides the major protection in the lung against neutrophil elastase-mediated proteolysis. Inheritance of alpha 1AT deficiency alleles is associated with an increased risk of emphysema and liver disease. alpha 1AT null alleles cause the total absence of serum alpha 1AT and represent the ultimate in a continuum of alleles associated with alpha 1AT deficiency. The molecular mechanisms responsible for absence of serum alpha 1AT include splicing abnormalities, deletion of alpha 1AT coding exons, and premature stop codons. We identified an Italian individual with asthma, emphysema, and a very low level of serum alpha 1AT. DNA sequencing demonstrated the Mprocida deficiency allele and a novel null allele, QOtrastevere (c654 G-->A, W194Z), a nonsense mutation near the intron 2 (IVS2) splice acceptor site. To determine the molecular basis of QOtrastevere and specifically to evaluate whether this nonsense mutation interfered with mRNA processing by altered splicing, we used a Chinese hamster ovary cell line permanently transfected with QOtrastevere or normal M alpha 1AT with and without IVS2. Northern blot analysis demonstrated that the normal M construct, with or without IVS2, expressed alpha 1AT mRNA of a similar size. The nonsense mutation was associated with moderately reduced alpha 1AT mRNA regardless of the presence or absence of IVS2. Reduction in alpha 1AT mRNA regardless of the opportunity for splicing supports a translational-translocation model as the cause of reduced alpha 1AT mRNA rather than the nuclear scanning model. Pulse-chase studies followed by immunoprecipitation demonstrated an endoplasmic reticulum-retained 31 kDa QOtrastevere alpha 1AT, which was rapidly degraded. Although mRNA content was moderately reduced, retention and rapid intracellular degradation of the truncated form are the major mechanisms for the absence of secreted alpha 1AT.

Alleles↗
PubMed1998

Immunogenetic basis of environmental lung disease: lessons from the berylliosis model.

The role of genetic factors has been hypothesized in the pathogenesis of a number of chronic inflammatory lung diseases. The genes of the major histocompatibility complex (MHC) locus on human chromosome 6 have been identified as important determinants in diseases caused both by inorganic and organic compounds such as beryllium, gold, acid anhydrides, isocyanates and grass pollens. Since many environmental factors are the determinants of the immunopathogenesis of asthma, pulmonary granulomatous disorders, hypersensitivity pneumonitis and fibrotic lung disorders, an understanding of the interaction between environmental factors is crucial to epidemiology, prevention and treatment of these disorders. Berylliosis is an environmental chronic inflammatory disorder of the lung caused by inhalation of beryllium dusts. A human leukocyte antigen class II marker (HLA-DP Glu69) has been found to be strongly associated with the disease. In in vitro studies, the gene has been shown to play a direct role in the immunopathogenesis of the disease. In human studies, the gene has been shown to confer increased susceptibility to beryllium in exposed workers, thus suggesting that HLA gene markers may be used as epidemiological probes to identify population groups at higher risk of environmental lung diseases, to identify environmental levels of lung immunotoxicants that would be safe for the entire population and to prevent disease risk associated with occupation, manufactured products and the environment. Studies on the associations between human leukocyte antigens and chronic inflammatory lung disorders are reviewed in the context of the berylliosis model.

Animals↗
PubMed1997

Interaction of genetic and exposure factors in the prevalence of berylliosis.

Prevalence of berylliosis, a lung disorder driven by the activation of beryllium-specific T cells, is associated with a major histocompatibility complex (MHC) class II marker (HLA-DPB1Glu69) and with the type of industrial exposure. We evaluated the interaction between marker and exposure in a beryllium-exposed population in which the prevalence of berylliosis was associated with machining beryllium. The presence of the marker was associated with higher prevalence (HLA-DPB1Glu69-positive machinists 25%; HLA-DPB1Glu69-negative machinists 3.2%, P = 0.05) and predicted berylliosis independent of machining history (odds ratios 11.8 and 10.1). The study shows that in berylliosis the carrier status of a genetic susceptibility factor adds to the effect of process-related risk factors.

Adult↗
PubMed1997

Serological markers predicting tuberculosis in human immunodeficiency virus-infected patients.

SETTING: Human immunodeficiency virus (HIV)-positive patients retrospectively identified at the Hospital of Bari, Italy, with diagnosis of tuberculosis (TB) (n = 30) or non-tuberculous pneumonia (n = 29). Serum samples drawn at the time of diagnosis and one year before. Anti-purified protein derivative (PPD) and anti-diacyltrehalose (DAT) serum antibodies quantified by ELISA assay. OBJECTIVE: Since TB patients with HIV infection may present with elevated serum antibodies against Mycobacterium tuberculosis, we hypothesized that TB-specific antibody markers might predict TB in these subjects. DESIGN: A retrospective study was designed to assess the presence of M. tuberculosis-specific antibodies in HIV-positive patients developing TB. RESULTS: Of 30 HIV-positive TB patients, 24 (80%) had anti-PPD or anti-DAT antibodies at the time of TB diagnosis, and 20 (67%) one year before. In a sub-population of 16 of the 30 HIV-positive subjects, positivity for anti-PPD or anti-DAT antibodies one year before TB diagnosis was higher (11/16, 69%) than for the PPD skin test (4/16, 25%, P < 0.01). Antibody tests were specific for TB since positivity rates were lower both in patients with non-tuberculous pneumonia (P < 0.01) and in those with M. avium infection (P < 0.05). CONCLUSION: Antibody markers may predict TB in HIV-positive subjects, including those with negative PPD skin test.

AIDS-Related Opportunistic Infections↗
PubMed1996

Minimal dose of aerosolized interferon-alpha in human subjects: biological consequences and side-effects.

Interferon-alpha (IFN-alpha) is a leucocyte-derived cytokine with pleiotropic effects on the cells of the immune system, including the ability to promote viral and microbial killing. This study was designed to evaluate the biologically active dosage of aerosolized lymphoblastoid IFN-alpha, in normal subjects and patients with chronic bronchitis, using serum 2'-5' oligoadenylate synthetase (OAS) as a marker of IFN-alpha activity. Three groups of subjects were included: two healthy groups and one of patients with chronic bronchitis. Group A (controls, n = 5) was studied in order to determine the minimal IFN-alpha dose able to induce biological effects without side-effects. IFN-alpha was given in a dose escalation trial including 0, 0.3 x 10(6), 1.0 x 10(6) and 3.0 x 10(6) IU.day-1 (5 day administration). Only the administration of 3.0 x 10(6) IU.day-1 of IFN-alpha induced a significant biological activity, increasing serum levels of OAS. Group B (controls, n = 5) and C (chronic bronchitis, n = 5) were given 3.0 x 10(6) IU.day-1 (10 day administration) in order to study serum, bronchoalveolar lavage fluid (BALF) and BALF cell modifications, after treatment. OAS serum levels and nitroblue tetrazolium (NBT) reduction tests, the latter used as a measure of phagocyte cell activity, increased both in normal subjects and in patients with chronic bronchitis. No significant change of serum IFN-alpha levels was found. It is concluded that aerosolized IFN-alpha administration to the lung is well-tolerated at biologically active doses. The activity can be monitored by quantifying OAS serum levels through a simple blood test.

2',5'-Oligoadenylate Synthetase↗
PubMed1996

Evaluation of a western blot serum test for the diagnosis of Mycobacterium tuberculosis infection.

This study was designed to evaluate the possibility of monitoring Mycobacterium tuberculosis infection using a serological assay. A discriminant score comprising antigen fractions of 38, 28, 24 and 19 kDa, identified in western blots using the Mycobacterium bovis bacille Calmette-Guérin (BCG) A60 antigen complex was established in a sample of 57 purified protein derivative (PPD)-negative and 47 PPD-positive individuals. It was then tested in a group of 140 subjects undergoing BCG vaccination as a model of tuberculosis complex infection and in a group of human immunodeficiency virus (HIV)-infected individuals as a model of cell-mediated immunodeficiency-related risk of tuberculosis. The discriminant score identified 57 out of 57 (100%) PPD-positives and none (0%) of the 47 PPD-negatives. In the BCG vaccinated subjects, 1.4% tested positive before vaccination and 90% after vaccination. In the HIV-positive subjects, 90% of the PPD-positive and 5% of the PPD-negative subjects had a positive score. This study suggests that the western blot discriminant score is an accurate test to survey M. tuberculosis infection in serum samples.

Adult↗
PubMed1995

Discriminant analysis on small cell lung cancer and non-small cell lung cancer by means of NSE and CYFRA-21.1.

A correct diagnosis of small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC) is essential both for prognostic and therapeutic reasons. We used discriminant analysis as a method to optimize the discriminant power of serum tumour marker levels for differentiation between SCLC and NSCLC. A panel of serum markers, including neurone specific enolase (NSE), cytokeratin fragment antigen 21.1 (CYFRA-21.1), tissue polypeptide antigen (TPA) and carcinoembryonic antigen (CEA) was obtained in 50 consecutive NSCLC and 17 SCLC. Data were analysed by the BMDP statistical program after logarithmic transformation of marker levels. The variables selected were NSE and CYFRA-21.1. Considered together, they were able to give a 97% rate of correct classification. The formula generated (canonic variable, CV) was validated on a group of seven SCLC and 22 NSCLC patients. Only two errors occurred. We therefore conclude that the canonic variable tested, based on NSE and CYFRA-21.1, provides a good discrimination between the two types of lung cancer. The method is rapid, relatively inexpensive, and based on simple serum tests.

Aged↗
PubMed1995

Molecular diagnosis of tuberculosis.

Rapid and sensitive tools for the diagnosis of tuberculosis are needed, due to the increased incidence of tuberculosis epidemics and the length of time required by classical diagnostic tests, especially among human immunodeficiency virus (HIV)-infected patients. In this context, the recent advances in cloning and characterization of M. tuberculosis genes has allowed the application of basic molecular biology techniques to the examination of clinical samples, such as sputum and bronchoalveolar lavage (BAL), for the molecular diagnosis of tuberculous infection. By using the polymerase chain reaction (PCR) for the amplification of mycobacterial nucleic acids and nonradiometric revelation techniques, the time required for the identification of mycobacteria has been considerably shortened (24-48 h), in comparison to the time required by microbiological tests. When PCR technique is performed by experienced laboratory personnel using controlled protocols, false-negative (caused primarily by endogenous polymerase inhibitors) and false-positive results (due to contamination) can generally be avoided, achieving sensitivity and specificity close to 100%. In the clinical practice, the use of molecular testing for the diagnosis of tuberculosis, in combination with "classic" diagnostic tools, can greatly enhance the diagnostic ability of pulmonary clinicians, particularly in paucibacillary infections and in patients with atypical presentation, such as immunodeficient individuals.

AIDS-Related Opportunistic Infections↗
PubMed1994

Use of discriminant analysis to assess disease activity in pulmonary tuberculosis with a panel of specific and nonspecific serum markers.

Several cell activation markers, acute phase reactants, enzymes, and antituberculous antibody serum levels have been proposed as possible markers to monitor disease activity in patients with tuberculosis. They have all shown limited sensitivity or specificity. The authors therefore attempted to generate a canonical variable using discriminant analysis, including sensitive and specific parameters, to be a reliable marker in classifying patients correctly during the course of pulmonary tuberculosis. The following parameters were selected: two soluble cell activation markers (soluble interleukin-2 receptor and sCD8); the levels of immunoglobulin (Ig) G and IgM antibodies against the A60 antigen complex; and the presence of specific antibodies directed to eight different A60 components, revealed by Western blot analysis. The tests were performed on sera from three groups of patients with pulmonary tuberculosis. The first group comprised 25 patients with onset tuberculosis, clinically active (OTCA), evaluated at the time of admission. The second group included 28 patients with chemotherapy-treated tuberculosis, clinically active (CTCA), 2 months after therapy had begun. The third group included 20 patients with tuberculosis, nonclinically active (TNCA), who had had at least 1 year of effective therapy. The authors obtained an 80.9% rate of correct classification for the three groups and a rate of 100% when OTCA and TNCA were compared. The patients with CTCA were scarcely differentiated and tended to be distributed into the two other groups. To improve the separation between patients with CTCA and those with OTCA, a second canonical variable was generated with a 91.7% rate of correct classification, as compared with 71% obtained using the sCD8 as the best single variable. The mean values of the last canonical variable were statistically different (Mann-Whitney test, P = .049) when stratified for acid fast bacilli-positive or negative CTCA patients (microscopic detection). Three patients, followed during the entire course their disease, were, as expected, correctly positioned with respect to the subsequent disease phases.

Adult↗