PubMed Health⌕ Search

Biomedical subjects

M C Mazeron

Publications and source records attributed to M C Mazeron.

At least 37 records · Page 2Linked to original sources
PubMed1994

Transient hydrops fetalis associated with intrauterine cytomegalovirus infection: prenatal diagnosis.

BACKGROUND: Intrauterine cytomegalovirus infection is usually unrecognized during pregnancy. However, in some cases, ultrasound abnormalities can be observed in association with cytomegalovirus infection. CASE: The prenatal diagnosis of cytomegalovirus infection in a fetus with transient hydrops is reported. Fetal ascites was first recognized by routine ultrasound examination at 20 weeks' gestation. Hydrops fetalis was obvious at 23 weeks and completely resolved 1 week later. Cytomegalovirus was detected from amniotic fluid samples by centrifugal culture and direct immunofluorescent examination. The diagnosis of maternal primary infection could be established retrospectively by demonstrating immunoglobulin (Ig) G and IgM seroconversion on sequential sera. The pregnancy was electively terminated. Autopsy findings were consistent with fetal disseminated infection. CONCLUSION: Transient hydrops fetalis in association with intrauterine cytomegalovirus infection is infrequent. The resolution of hydrops fetalis could be explained by hepatic dysfunction of limited duration. Amniotic fluid culture is a reliable approach for diagnosing intrauterine cytomegalovirus infection, but does not predict the severity of the disease or the outcome of the pregnancy. The long-term clinical significance of intrauterine cytomegalovirus infection has to be established.

Adult↗
PubMed1993

Rapid detection of cytomegalovirus strains resistant to ganciclovir through mutations within the gene UL97.

The human cytomegalovirus (HCMV) gene UL97 product was shown to play an important role in phosphorylation of ganciclovir (GCV) in HCMV-infected cells. The deletion of the 4 amino-acid sequence AACR confers resistance to a laboratory mutant. The aim of this study was to develop a rapid and simple method to detect mutations within the 12 base pair (bp) fragment encoding AACR, from isolates and clinical specimens (urine, bronchoalveolar lavage, cerebral spinal fluid samples). A target region encompassing this 12bp sequence was amplified by a single-step PCR assay from HCMV isolates and reference strains, and a two-step procedure from clinical specimens. Reaction products were submitted to restriction enzyme analysis and dot-blot hybridization assay. Two biotinylated probes were used: one probe (DL) overlapping the 12bp region; and a control probe with similar length and GC content. Hybridization was performed under conditions allowing the detection of one bp deletion (HCMV strain susceptibility to GCV was determined by a rapid late antigen synthesis reduction assay.) The control probe hybridized to the UL97 sequence amplified from all 23 tested isolates and the reference strains. The DL probe gave a positive signal with GCV-susceptible strains; no signal was obtained for five out of seven resistant isolates, and for a laboratory mutant derived from the strain AD169. Restriction analysis of amplification products showed different patterns suggesting this region can be involved in various DNA changes.(ABSTRACT TRUNCATED AT 250 WORDS)

Base Sequence↗
PubMed1993

Cytomegalovirus antigenemia assay: therapeutic usefulness and biological significance.

The cytomegalovirus antigenemia test is based on immunocytochemical detection of HCMV early structural protein pp65 in the nuclei of polymorphonuclear blood leucocytes of patients with systemic infection. Specificity and sensitivity are > or = 90% and positivity correlates well with HCMV disease, allowing better monitoring than isolation from buffy coat of patients undergoing chemotherapy. Polymorphonuclear cells appear as a main site of initial HCMV infection and reactivation.

Antigens, Viral↗
PubMed1993

[Human cytomegalovirus infection: new methods for virological diagnosis].

Recently developed methods have greatly increased the sensitivity and speed of virological diagnosis of cytomegalovirus infection. Virus can be detected in infected cell cultures within 24 or 48 hours of specimen inoculation by using monoclonal antibodies to immediate-early antigens in immunocytochemistry procedures or DNA sequences in hybridisation in situ assays. CMV antigens can also be detected directly in infected cells within clinical specimens. An early antigen can be visualized in nuclei of circulating leukocytes from viremic patients. DNA hybridization is used for CMV analysis in Dot-blot, Southern-blot and in situ hybridization assays. DNA amplification, by polymerase chain reaction (PCR), has proven to be a very sensitive method for diagnosis of CMV infection and should be useful for investigation of CMV pathogenesis and latency. Serologic assays such as ELISA and latex agglutination assays are accurate for screening donors and recipients of blood and organ or marrow graft. Studies of viral protein epitopes recognized by human sera are in progress.

AIDS-Related Opportunistic Infections↗
PubMed1992

Comparison of MRC-5 and continuous cell lines for detection of cytomegalovirus in centrifugation cultures.

Continuous cell lines were assessed for use for rapid human cytomegalovirus (HCMV) detection procedures combining tissue culture, centrifugation, and immediate early antigen (IEA) immunostaining. Human cells (MRC-5 embryonic fibroblasts, U-373MG astrocytoma cells, differentiated teratocarcinoma (Tera-2) cells), murine cells (BALB/c-3T3 and Y-1 cells), BHK21 hamster cells, and mink lung (ML) cells were first inoculated with HCMV laboratory strain. IEA synthesizing cells were detected by immunoperoxidase assay using a monoclonal antibody. ML cells and differentiated Tera-2 cells exhibited more positive cells than MRC-5 cells. BHK21, and MRC-5 cells were equivalent in sensitivity whereas U-373MG, BALB/c-3T3, and Y-1 cells had only reduced IEA positive cells. When 63 urine specimens were inoculated onto MRC-5, ML and differentiated Tera-2 cells, 20 (31.7%) were positive in MRC-5 cells versus 18 (28.5%) in ML or Tera-2 cells. Moreover, greater numbers of infected cells were detected in MRC-5 cells than in these two cell lines. MRC-5 cells were superior for detection of HCMV in clinical samples by centrifugation cultures.

Animals↗
PubMed1992

Circulating interferon in cytomegalovirus infected bone-marrow-transplant recipients and in infants with congenital cytomegalovirus disease.

In a study concerning five CMV-infected bone-marrow-transplant recipients, five congenital CMV diseases and appropriate controls, presence of high levels of circulating interferon (IFN) was demonstrated exclusively during the course of CMV disease. This interferon was predominantly "immune" or gamma interferon (gamma-IFN). These results suggest that during CMV disease the interferon compartment of the immune response is modified.

Anemia, Aplastic↗
PubMed1992

Monoclonal antibody E-13 (M-810) to human cytomegalovirus recognizes an epitope encoded by exon 2 of the major immediate early gene.

Monoclonal antibody (MAb) E-13 to human cytomegalovirus is used widely for diagnostic and fundamental studies, and has been shown to be directed against an immediate early (IE) protein(s). To determine which viral antigen is detected by MAb E-13, four subfragments from the open reading frame encoded by exons 2, 3 or 4 of IE-1 were cloned in the bacterial expression vector pROS. The resulting fusion proteins contained amino acids 77 to 491 encoded by mainly exon 4, amino acids 25 to 78 encoded by exon 3, amino acids 1 to 85 encoded by exons 2 and 3, and amino acids 1 to 24 encoded by exon 2. The reactivity of MAb E-13 with the fusion proteins was assayed by Western blotting. MAb E-13 was shown to react exclusively with proteins encoded by exon 2 and therefore recognizes IE proteins which contain the N-terminal amino acid sequence encoded by exon 2, namely the major 72K IE protein, the 82K to 86K IE-2 protein and the 52K to 55K IE-2 protein. MAb E-13 can be used to detect both IE-1- and IE-2-encoded proteins, which share the polypeptide encoded by exon 2.

Antibodies, Monoclonal↗
PubMed1990

Opportunistic agents in bronchoalveolar lavage in 99 HIV seropositive patients.

During a ten month period, 117 fibreoptic bronchoscopies and bronchoalveolar lavages (BAL) were performed in human immunodeficiency virus (HIV) infected patients suspected of having opportunistic pulmonary infections. The BAL were classified into 3 groups, according to clinical manifestations related to HIV infection at the time of fibreoptic bronchoscopy: pre-acquired immunodeficiency syndrome (AIDS) (n = 54), AIDS with Kaposi's sarcoma (n = 37), AIDS without Kaposi's sarcoma (n = 26). On chest X-ray, diffuse infiltrates were most common (54%), followed by normal X-rays (24%) and localized infiltrates (18%). Amongst the 117 BAL, 68 (58%) yielded at least one opportunistic agent. In 28 BAL performed for pulmonary signs or unexplained fever with normal chest X-rays, one or several opportunistic agents were isolated in 17 samples of BAL fluid. The most frequently identified opportunistic agents were Pneumocystis carinii (in 38% of BAL) and cytomegalovirus (35%); these were associated in 17% of BAL. There was no statistically significant difference in opportunistic agents among the 3 groups of BAL (pre-AIDS, AIDS with Kaposi's sarcoma, AIDS without Kaposi's sarcoma). In particular, cytomegalovirus was found in BAL with the same frequency in these 3 groups.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Treatment of severe cytomegalovirus infection with ganciclovir and high-dose intravenous immunoglobulin in patients with allogeneic bone marrow transplants. A pilot study.

Cytomegalovirus (CMV) infection is the leading infectious cause of death after bone marrow transplantation (BMT) because of the high mortality rate associated with CMV pneumonia. However, very interresting results were recently reported when treating CMV penumonia with the combination of ganciclovir and high doses of intravenous anti-CMV immunoglobulin. In order to achieve an even better therapeutic efficacy, we have conducted a pilot study consisting of early administration of the combination therapy, as soon as CMV was isolated from the material obtained by bronchoalveolar lavage (BAL). A BAL was performed when symptoms of severe CMV infection were present and sometimes also systematically when an asymptomatic CMV viremia was diagnosed. Out of 18 BMT patients with CMV isolated from BAL in the absence of pulmonary signs, 9 became long-term survivors without any episode of CMV pneumonia and 9 died. However, only 2 patients died because of CMV pneumonia. Early treatment with the combination of ganciclovir and anti CMV immunoglobulin seems thus to decrease the incidence of CMV pneumonia (2/18) as it is known that about half of the untreated patients with CMV viremia will develop CMV pneumonia. We have also used the combination therapy to treat 3 cases of CMV pneumonia. As 2 patients survived the CMV pneumonia episode, this confirms the possible effectiveness of the combination therapy for the treatment of established CMV pneumonia. However, our pilot study points out the usefulness of an early treatment. At such an early stage, application of the combination therapy could affect the intensity and length of treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone Marrow Transplantation↗
PubMed1987

Comparative study of tissue culture and mouse inoculation methods for demonstration of Toxoplasma gondii.

Two methods for the isolation of Toxoplasma gondii were analyzed and compared. Bradyzoites or tachyzoites of three strains of T. gondii were injected into mice and introduced in parallel onto MRC5 fibroblasts cultured on cover slips. In the cultures, the parasites were more readily identified by an indirect immunofluorescence assay than by examination of unstained or Giemsa-stained cultures. With the RH strain, the tachyzoites replicated actively, and large foci of parasites were observed in 24 h. The bradyzoites or tachyzoites of the other strains could also be cultivated, but grew rather slowly; 2 days after inoculation, early stages of multiplication could be observed: from day +4, Toxoplasma clusters or foci were easily identified at a x100 magnification. The course of infection in mice was greatly dependent on the virulence of the strain and on the parasitic stage inoculated. In the chronically infected mice, evidence of Toxoplasma infection was only detected 45 days after inoculation through the demonstration of cysts in the brain or the presence of specific antibodies in the serum. The mean ratio of infected mice and positive cultures was compared in relation to the inoculum size. The tissue culture method was found to be at least as sensitive as mouse inoculation. Since Toxoplasma organisms may be isolated within a few days in tissue culture, it is proposed that this method should be used when early isolation of the parasite is crucial for the diagnosis of toxoplasmosis.

Animals↗
PubMed1987

[Early detection of cytomegaloviruses from pathological matter and feces].

CMV can be isolated within 24 or 48 h post-infection of human diploid fibroblasts cells cultures by detection of immediate early antigen with immunological techniques using E13 monoclonal antibody. Optimal enhancement of CMV detection is obtained by centrifugation at 4,000 g for 45 minutes of specimen inoculum onto cell culture monolayers. Rapid immunodiagnosis can be applied to cells from clinical specimens faster than with culture but it is less sensitive. This rapid diagnosis of CMV infection enables early prescription of appropriate antiviral chemotherapy.

Antigens, Viral↗
PubMed1987

[Value of the detection of serum anti-cytomegalovirus antibodies applied to the diagnosis of recent infection].

Cytomegalovirus (CMV) infection is a major cause of morbidity in immunodepressed patients: the diagnosis is based on the demonstration of CMV viraemia and/or specific IgM and/or a significant rise in antibody titres. This study was undertaken to compare the diagnostic value of these parameters. Eighteen patients with the AIDS and CMV infection were investigated; CMV viraemia was demonstrated in 87 p. 100 and specific IgM in 23 p. 100 of cases; in 24 patients followed up for 4 months after bone marrow transplantation viraemia was demonstrated in 70 p. 100 and IgM in 54 p. 100 of cases; however, the detection of IgM was often late. In contrast, specific IgM is frequently detected in CMV infection of non-immunodepressed patients.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Clinical significance of cytomegalovirus viremia in bone marrow transplantation.

Cytomegalovirus (CMV) viremia was systematically studied in 56 patients having undergone bone marrow transplantation for leukemia or aplastic anemia. Of the patients who survived at least three months, 57% had CMV viremia with a frequency peak between the 7th and the 9th weeks. We describe possible clinical signs associated with viremia, particularly late peripheral and/or central thrombocytopenia. The occurrence of viremia was studied according to the specific preexisting immune status of recipients and donors; granulocyte transfusions and graft-versus-host disease. The relationship between these parameters and viremia provides a basis for the analysis of prophylactic treatments of CMV infection.

Adolescent↗
PubMed1984

[Direct diagnostic methods for the demonstration of cytomegaloviruses in the blood].

CMV can be detected in blood with two techniques: isolation of CMV from the buffy-coat on human embryonic fibroblasts; CMV genome detection by DNA hybridization technique. Isolation of CMV from blood plated on embryonic fibroblasts necessitates a delay of 10-30 days. Using monoclonal antibodies we have developed a 96 hours test to diagnose viremia. Fibroblasts grown on coverslip in tubes are inoculated with buffy-coat. Indirect immunofluorescence test is performed using the monoclonal antibodies E 13, 48 and 96 hours post-infection. DNA-DNA hybridization technique necessitates purification of CMV DNA. CMV DNA is then labelled with 32 P by nick-translation. This labelled DNA is used as probe for detection of CMV genome in DNA extracted from leukocytes. The hybridization is virus-specific. Cytomegaloviremia correlates with active infection and is not indicate of the carrier state of blood donors. CMV genome research in blood can potentially identify infective donors. Further studies are needed to correlate CMV genome detection in blood with presence of CMV antibodies.

Blood Donors↗