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Biomedical subjects

M C Maroto

Publications and source records attributed to M C Maroto.

At least 19 recordsLinked to original sources
PubMed2004

Retrospective analysis of antiretroviral HIV treatment success based on medical history or guided by the reverse hybridisation LiPA HIV genotyping system.

The changes in viral load and CD4(+) count at 3 and 6 months in a group of 166 HIV-infected patients was evaluated. The new therapy was chosen based on the medical history procedures for 70 patients, and in 96 patients it was guided by the partial or complete result of the line probe assay (LiPA) HIV RT and Protease resistance tests. The absolute difference from the baseline of the log viral load at 3 and 6 months was significantly different between the two groups when adjusted for baseline viral load (P < 0.0001) and stayed significant when intention-to-treat analysis was carried out (P < 0.001). The absolute difference of the CD4(+) count was not significantly different when adjusted for baseline CD4(+) (P = 0.854, 3 months; P = 0.06, 6 months). The proportion of patients with a viral load </=200 cp/ml in the medical history group (14.5%, 3 months; 15.2%, 6 months) was significantly different from the proportion of responders in the LiPA group (28.7%, 3 months, P = 0.03; 34.7%, 6 months, P = 0.008). In the intention-to-treat population, the difference between the two groups remained significant (P = 0.01). There was no statistical difference between the two groups in terms of adherence (P = 0.88), number of drug failures (P = 0.12) and for the time since starting treatment (in years) (P = 0.48), but there was a significant difference for the number of new drugs in the new regimen (P < 0.0001) and for the pill burden of the treatment (P = 0.0006). A higher antiretroviral HIV treatment success guided by the LiPA HIV genotyping system than that based on the medical history only is reported. Of note, this study reached the same conclusions as previous studies, which all used sequencing.

Adult↗
PubMed2002

ELISA test to detect Chlamydophila pneumoniae IgG.

A new ELISA test (Chlamydophila pneumoniae IgG, Vircell, Spain) to detect Chlamydophila pneumoniae IgG was evaluated. The micro-immunofluorescence (MIF) test was used as reference method. Chlamydia trachomatis and Chlamydophila psittaci elementary bodies were also assayed. Two hundred and sixteen sera were included in the study: 66 from patients with peripheral arterial occlusive disease (Panel 1), 68 from adults with pneumonia (Panel 2), 44 from healthy adults (Panel 3) and 38 from patients with a sexuality transmitted disease by C. trachomatis (Panel 4). In Panel 1, 51 sera (77%) had antibody titres between 32 and 128; 4 out of 15 sera with IgG titres < 32 were positive by ELISA test and 2 sera with 32 IgG titres were uncertain by ELISA; the remaining 60 sera were correctly classified, giving a 91% concordance between the techniques. In Panel 2, 55 sera (81%) had IgG titres between 32 and 512; 2 out of 13 sera with IgG titres < 32 were positive by ELISA and 2 sera with 32 titres were uncertain by ELISA; the remaining 64 sera were correctly classified, giving a 97% concordance. In Panel 3, 22 sera (50%) had IgG titres between 32 and 64; only 1 out of 22 sera with IgG titres < 32 was positive by ELISA, giving a 97% concordance between the techniques. In Panel 4, there were 24 (63%) negative, 10 (26%) uncertain and 4 (10%) positive results by ELISA, giving an 86% concordance. The C. pneumoniae ELISA test demonstrated 100% sensitivity and 85% specificity. The IgG ELISA test demonstrated a good concordance with the MIF test without the drawbacks associated with the latter assay. We conclude that the ELISA test could be an alternative to the MIF test.

Antibodies, Bacterial↗
PubMed2002

Multiple sclerosis and human herpesvirus 6.

BACKGROUND: A possible but as yet unproven relationship has been proposed between the onset or persistence of multiple sclerosis (MS) symptoms and herpesviruses, including, most recently, human herpesvirus 6 (HHV-6). A study was conducted to investigate the presence of HHV-6 DNA and the synthesis of antibodies against HHV-6, cytomegalovirus (CMV) and Epstein-Barr virus (EBV) in serum and cerebrospinal fluid (CSF) of patients with MS. MATERIALS AND METHODS: PCR and ELISA were used to detect HHV-6 DNA and specific antibodies against HHV-6, CMV and EBV in 211 samples (139 sera and 72 CSF). There were three groups of samples: group I, paired samples of serum and CSF from 41 MS patients; group II, paired samples of serum and CSF from 31 patients with neurological diseases other than MS (OND); group III, 67 serum samples from 27 different MS patients undergoing serologic follow-up. RESULTS: No HHV-6 DNA was found in any sample. Group I sera showed elevated anti-HHV-6 IgG and IgA levels. In group II, anti-CMV IgG was detected in one CSF sample and anti-HHV-6 IgM in one serum sample. Group III sera showed high concentrations of anti-HHV-6 IgG, IgA and IgM. CONCLUSION: Given the clinical implications of the presence of antibodies against HHV-6 in MS patients, a viral reactivation cannot be excluded as an environmental factor.

Adult↗
PubMed2001

HGV RNA sequences in liver and PBMC.

HGV has been identified in patients with chronic hepatitis of unknown aetiology and the possibility that HGV may be the cause has been raised. We have analysed liver biopsies and PBMC (peripheral blood mononuclear cells) from 80 patients with chronic hepatitis and HGV-RNA in serum by PCR. In ten patients HGV-RNA was detected in liver, in five patients it was detected in PBMC and seven were positive in both specimens by PCR. Whether this agent resides and replicates in hepatocytes remains controversial and needs more studies.

Base Sequence↗
PubMed2001

An evaluation of a polyantigenic ELISA to detect Epstein-Barr virus reactivation.

The diagnostic reliability of the Enzygnost EBV test (DadeBehring, Germany) for the detection of IgG and IgA antibodies in the diagnosis of Epstein-Barr virus (EBV) recurrent disease was investigated. Of 81 serum samples examined there were fourteen asymptomatic patients without EBV infection, 46 with past EBV infection, and 21 patients with EBV reactivation. The Enzygnost EBV test was based on an enzyme-linked immunosorbent assay with a pool of viral antigens. The reliability of IgG at >650 IU/ml, and IgA for the diagnosis of reactivation or chronic persistent EBV infection gave 100% sensitivity, 83.3% and 98.3% specificity, respectively. The data indicated that the appearance of EBV IgA was associated with EBV reactivation together with clinical manifestations.

Antibodies, Viral↗
PubMed2000

Antibodies to Borrelia burgdorferi in European populations.

We compared the antibodies to B. burgdorferi in three different populations in order to evaluate the diagnostic reliability of Lyme borreliosis serologic analysis. The subjects included 25 patients with Lyme borreliosis (Group 1); 50 patients with diseases of unknown cause, B. burgdorferi ELISA-positive in serum and without B. burgdorferi infection (Group 2); and 1,251 individuals without Lyme borreliosis (Group 3). All samples were tested for B. burgdorferi B31 and B. afzelii antigens using ELISA. The positive results of the ELISA B. burgdorferi B31 assay were confirmed with Western blot for the same strain. In Group 3, 162 (12.9%) patients were ELISA positive for B. burgdorferi B31, while only 6 (0.6%) patients had IgG ELISA antibodies to B afzelii. Bands in WB were detected in 104 (8.4%) of the Group 3 subjects. The bands found to be most reliable for the identification of strain B. burgdorferi B31 by IgG WB were those representing the 93, 39, 34, and 23-kDa proteins. Our results show that serologic diagnosis of Lyme borreliosis is far from clearly established. To date, the only reliable criteria are clinical ones correlated with laboratory evidence.

Adolescent↗
PubMed2000

Detection of mycobacterial DNA in papulonecrotic tuberculid lesions by polymerase chain reaction.

Tuberculids are a heterogeneous group of cutaneous lesions. Recent discoveries of M. Tuberculosis DNA in these lesions by PCR suggest that M. tuberculosis could play a role in their pathogenesis. The aim of this study was to demonstrate the presence of M. tuberculosis DNA by polymerase chain reaction in papulonecrotic tuberculid lesions. Skin biopsy specimens from ten patients with papulonecrotic tuberculid lesions (histopathologic features) were studied. All of them tested solidly positive in a tuberculin intradermal test. A gene-amplification PCR, using primers capable of amplifying DNA in the M. tuberculosis complex, was performed to detect M. tuberculosis DNA in the lesions. A 285-bp sequence specific of M. tuberculosis complex was amplified and confirmed by Southern-blot hybridation with a 32 p 5'-labelled internal probe. No inhibitors were detected in the negative PCR samples. The PCR technique makes the detection of mycobacterial DNA in tuberculids a possibility, and therefore provides a rational basis for antituberculous therapy and for the clinical management of these disorders.

Biopsy↗
PubMed2000

Prevalence and viral persistence of TT virus in patients on hemodialysis.

The aim of this study was toevaluate the prevalence of TT virus (TTV) in 107 hemodialysis patients and 100 healthy individuals. Sixteen percent of hemodialysis patients and 2% of the control population were TTV positive (P<0.001). Sex, time on dialysis, transfusions, and alanine aminotransferase levels were not related to the presence of TTV DNA. TTV was more frequent in patients 50 to 70 (12/51) years of age and persisted in the serum of six of nine patients 8 months later. TTV was found in peripheral blood mononuclear cells of all patients with chronic infection, and sequence variation was noted in the peripheral blood mononuclear cells of two patients. No relationship between TTV infection and hepatitis was observed. Viral persistence and nonparenteral transmission may be possible in patients on hemodialysis.

Aged↗
PubMed2000

Genomic variability of hepatitis G virus/GBV-C at the NS3 region: clinical implications.

A new hepatitis virus, named GBV-C or hepatitis G virus (HGV), closely related to the hepatitis C virus (HCV), was identified in 1994. The existence of quasispecies in HCV is very important. In this work polymerase chain reaction amplification of the NS3 region of the genome of GBV-C/HGV and heteroduplex mobility assay (HMA) were combined to investigate the presence of quasispecies in patients with chronic infection by GBV-C/HGV. Patients with chronic infection by HCV were used to validate the method. The HMA was also used to investigate the similarity between the cited genomic region of GBV-C/HGV in different infected patients. A high degree of heterogeneity was found for HGV existing as quasispecies and as differences between samples. This is of extreme importance because of the intrinsic clinical and pathogenic implications of quasispecies of a virus capable of producing disease, and is in accord with other studies which report on the genomic variability of the NS3 region.

Antiviral Agents↗
PubMed2000

Detection of HCV and GBV-CHGV RNA in peripheral blood mononuclear cells of patients with chronic type C hepatitis.

Hepatitis C virus (HCV) and hepatitis G virus (HGV) viraemia were investigated by RT-PCR protocols in peripheral blood mononuclear cells (PBMC) of 22 patients with chronic type C hepatitis. Samplings were at basal and 4-8 months after a 12 month period of treatment with interferon-alpha. A plus strand of HCV in PBMC was detected in 8 of 21 patients (38%) (p <0.05; chi2 test) with a lack of response to therapy; a minus strand was detected in 10% of chronic type C hepatitis and 25% of the patients harboured HCV RNA in PBMC. The association with a response was nearly significant (p <0.1; chi2 test). GBV-C/HGV RNA was detected in the serum of 9 of 21 (43%) patients and in PBMC of 20% of the patients viraemic. Genomic sequences of GBVC/HGV in PBMC were found, but further investigation is needed to assess the findings reported for HCV.

Flaviviridae↗
PubMed2000

Anti-hepatitic C virus antibodies hidden in circulating antibody/antigen aggregates in HCV-RNA positive patients.

The aim of this study was to determine whether antibodies to HCV can be hidden in immunocomplex aggregates in anti-hepatitis C virus (HCV) negative, HCV-RNA positive patients and whether their presence could be related to HCV viral load or HCV genotype. Sera (23 in toto) from patients with elevated alanine aminotransferase (ALT) levels and negative for anti-HCV but positive for HCV-RNA and the immunocomplex aggregates (precipitate with PEG 6000 and glycine 1 M) were studied. The sera were treated using a rapid, simple new ELISA which disrupted the immunocomplex aggregates. Sera from ten patients were tested anti-HCV positive after immunocomplex disruption. No correlation with age, sex, ALT level, viral load or HCV genotype was observed. In some patients anti-HCV antibodies were hidden in circulating antibody/antigen complexes which could be dissociated with a simple, inexpensive and rapid protocol; therefore it can provide a valuable addition to the diagnosis of HCV infection and it may prevent some cases of post-transfusion hepatitis.

Adult↗
PubMed2000

Comparison of several ELISA tests for detecting the presence of IgG and IgM against herpes simplex viruses.

Four enzyme-linked immunosorbent assays designated test 1 (ETI-HSVK-G 1/2); test 2 (ETI-HSVK-M 1/2); test 3 (ETI-HSVK-G 2), and test 4 (BioElisa HSV2 IgG) were studied to evaluate different stages of herpes simplex virus (HSV) infection. Samples (50 sera and 14 cerebrospinal fluid) were included in four groups. Group 1 consisted of samples from patients with primary HSV infections; group 2 comprised samples from patients with recurrent HSV infections; group 3 were samples nonreactive to HSV; and group 4 were samples from patients with infections by other herpes viruses (4a, chickenpox; 4b, herpes zoster; and 4c, infectious mononucleosis by Epstein-Barr virus). The percentages of agreement between tests 1 and 2 were 100 and 72.1%, respectively. The total diagnostic values of tests 1 and 2 were: 100 and 50% sensitivity, respectively; and 100 and 89% specificity, respectively. Few positive results for HSV-2 infection were found, and so, tests 3 and 4 were not evaluated. The results of tests 3 and 4 for a chickenpox patient, and a herpes zoster patient were not in agreement.

Antibodies, Viral↗
PubMed1999

Reliability of low-avidity IgG and of IgA in the diagnosis of primary infection by rubella virus with adaptation of a commercial test.

The detection of IgA and low-avidity IgG and antibodies in serum is a potentially useful marker of recent infection by a microorganism. We studied the reliability of IgG avidity and presence of IgA for the diagnosis of recent acute infection by rubella virus. Low-avidity IgG (Avy-EIA test) was determined with a modified commercial test using 8 molar urea (indirect ELISA, DiaSorin, Italy) and IgA was determined with a homemade indirect ELISA test. Twenty-five patients with recent primary infection by rubella virus (group I) and 50 healthy subjects (group II) were studied. In group I low-avidity IgG varied between 100 and 0% (67.3+/-21.8%); IgA was present in 24 patients (96%). In group II low-avidity IgG varied from 50.4 to 0% (19.8+/-16.9%). IgA was present in 2 subjects (4%). The sensitivity of the Avi-EIA and the IgA test was 92 and 96%, respectively; specificity was 100 and 96%, respectively. We conclude that both low-avidity IgG and IgA tests are helpful and reliable for the diagnosis of recent primary infection.

Adult↗
PubMed1999

Clinical reliability of IgG, IgA, and IgM antibodies in detecting Epstein-Barr virus at different stages of infection with a commercial nonrecombinant polyantigenic ELISA.

We studied the diagnostic reliability of a modification of the Enzygnost EBV test (Behringwerke, Germany) for the detection of IgG, IgA, and IgM antibodies (Abs) in the diagnosis of Epstein-Barr virus (EBV) disease. One hundred and twenty-three serum samples were studied: 14 asymptomatic subjects without EBV infection, 48 patients with primary infection, 46 subjects with past EBV infection (11 patients with other acute infections), 8 patients without EBV infection but with other viral infection, and 7 patients with probable acute clonal stimulation of B lymphocytes caused by different microorganisms. Enzygnost EBV is based on an ELISA test with a pool of viral antigens. In our series the reliability of IgM for the diagnosis of recent primary EBV infection was: sensitivity 100%, specificity 95%, positive predictive value 90.5%, and negative predictive value 100%. The IgG detection with Enzygnost was: sensitivity 98%, specificity 100%, positive predictive value 100%, and negative predictive value 91.7%. Only two subjects had positive IgA. The Enzygnost test is an efficient method for the diagnosis of EBV infection although a few IgM false positives can occur.

Antibodies, Viral↗