Search PubMedSearch

Biomedical subjects

L Perrin

Publications and source records attributed to L Perrin.

At least 55 records · Page 3Linked to original sources

Lack of monomeric IgM anti-hepatitis C virus (HCV) core antibodies in patients with chronic HCV infection.

Antibodies of the IgM class against the hepatitis C virus core antigen are found in up to 70% of patients with either acute or chronic hepatitis C. The sedimentation rate of such IgM was analyzed by rate-zonal centrifugation of nine sera taken from seven patients, two acutely and five persistently infected with hepatitis C virus. All patients had circulating high-molecular weight (i.e. pentameric) IgM, indicating that the production of low molecular weight IgM, commonly observed in other persistent viral infections, does not apply to hepatitis C virus and cannot be used to distinguish acute from chronic hepatitis C virus infection.

Chronic Disease

The Drosophila teashirt homeotic protein is a DNA-binding protein and modulo, a HOM-C regulated modifier of variegation, is a likely candidate for being a direct target gene.

The Drosophila teashirt (tsh) gene has an homeotic function which, in combination with HOM-C genes, determines thoracic and abdominal (trunk) identities. Analysis of TSH protein distribution during embryogenesis using a specific polyclonal antibody shows that it is nuclear. The protein is present with regional modulation in several tissues within the trunk, suggesting additional tsh functions to those already studied. We identified a candidate tsh target shared with some HOM-C genes, the modifier of variegation gene modulo (mod). The TSH zinc-finger protein recognizes in vitro two specific sites within a 5' control element of the mod gene which responds in vivo to tsh activity. TSH is therefore a DNA binding protein and might directly control mod expression.

Animals

Prognostic value of viremia in patients with long-standing human immunodeficiency virus infection. Swiss HIV Cohort Study Group.

Human immunodeficiency virus (HIV) viremia was evaluated in 73 patients with long-standing infection to investigate its relationship with clinical or biologic parameters and to assess its use as a predictor of clinical progression and death. After adjustment for other parameters, baseline HIV RNA level was significantly associated with baseline clinical stage and CD4 cell count. During follow-up (mean, 14.6 months), 16 patients died; 34 others had clinical progression of disease. In multivariate analysis, mortality was better predicted by baseline CD4 cell count (relative hazard [RH] for 100-cell decrease, 3.5; 95% confidence interval [CI], 1.5-8.2; P = .003) than by HIV RNA (P = .28) or clinical stage. HIV RNA level was the best predictor of clinical progression (RH for 1 log increase, 2.8; 95% CI, 1.6-4.9; P < .001). Monitoring of HIV RNA level may help to identify patients who might benefit from antiretroviral or prophylactic therapy.

Adult

Combined therapy with zidovudine and L-697,661 in primary HIV infection.

OBJECTIVE: To decrease viraemia levels in primary HIV infection by using a combination of zidovudine (ZDV) and L-697,661. DESIGN: Four primary HIV-infected patients were treated for 6 months with ZDV, 250 mg twice daily, in association with the non-nucleoside reverse transcriptase inhibitor L-697,661 500 mg three times daily. Viraemia, proviral DNA, CD4 and CD8 cell counts were measured serially during 18 months. RESULTS: Viraemia decreased to undetectable levels (< 200 RNA copies/ml) in two patients. A third patient had a marked decrease followed by a rebound during therapy; viraemia levels did not vary markedly in the fourth patient. A rebound in viraemia levels was observed within 15 days of discontinuation of therapy in the three responding patients. Proviral levels evolved in parallel with viraemia but were always detectable in all patients. In the three patients with an initial decrease of viraemia, CD4 cell counts were within the normal range 2 months after initiation of therapy and did not markedly decrease after discontinuation of therapy. In the two patients with partial or no response of viraemia, mutations associated with low level of resistance to L-697,661 appeared during treatment. CONCLUSION: A marked decrease of viraemia can be achieved in some primary HIV-infected patients with combined therapy. Six months of treatment does not prevent a rebound of viraemia, which was observed within 15 days of interruption of therapy.

Adult

Plasma levels of soluble CD30, tumour necrosis factor (TNF)-alpha and TNF receptors during primary HIV-1 infection: correlation with HIV-1 RNA and the clinical outcome.

OBJECTIVES: The immunological and virological events associated with primary HIV-1 infection have a major impact on the course of HIV-1 disease, and the identification of early predictors during primary HIV infection is critical for the therapeutic strategy. DESIGN AND METHODS: Eighteen consecutive patients with primary HIV infection were followed for a median of 398 days. Clinical status, CD4+ T-cell counts, and plasma samples were obtained weekly from enrollment until week 6, then at weeks 12, 24 and 52, and every 6 months thereafter. Seroconversion was assessed by anti-HIV-1/2 antibodies and Western blot analysis. HIV-1 RNA in plasma was quantified by Amplicor HIV Monitor test. Samples were assayed for immune complex-dissociated p24 antigen, tumour necrosis factor (TNF)-alpha, soluble TNF receptor (sTNFR)-1, sTNFR-II, sCD30 and sCD8 by enzyme immunoassays. Outcome was defined as entering clinical category B or C according to the Centers for Disease Control and Prevention criteria. As a control group, we included 23 HIV-1-negative healthy blood donors. RESULTS: Plasma levels of sCD30, TNF-alpha and sTNFR were significantly higher in HIV-1-infected patients than in controls, and were positively correlated with each other and with values of HIV-1 RNA. Patients who developed an outcome (n = 4) had significantly higher levels of sCD30, TNF-alpha and sTNFR compared with those who did not. Multivariate logistic regression analysis showed that sCD30 and TNF-alpha were the best predictors of outcome independently of CD4+ T-cell counts. CONCLUSIONS: During primary HIV infection, a persistent immune activation may be associated with a poor clinical outcome. The identification of sCD30 and TNF-alpha levels in plasma as early predictors of outcome in primary HIV infection, may direct the implementation of early therapeutic strategies in patients with elevated risk of disease progression.

Antigens, CD

Rapid and sensitive detection of enteroviruses in specimens from patients with aseptic meningitis.

A 5-h PCR assay (Amplicor enterovirus test) was compared with viral culture for the detection of enteroviruses in cerebrospinal fluid. Of the cerebrospinal fluid specimens collected during a summer outbreak of aseptic meningitis, 34% were positive by viral culture whereas 66% were positive by the Amplicor PCR, suggesting that this technique improves the diagnosis of enteroviral meningitis.

Base Sequence

Infection of primary human microglia and monocyte-derived macrophages with human immunodeficiency virus type 1 isolates: evidence of differential tropism.

To ascertain whether viruses present at the time of primary viremia can infect the central nervous system and to determine if microglial tropism is distinct from tropism for monocyte-derived macrophages (MDM), 27 human immunodeficiency virus type 1 (HIV-1) isolates obtained from acutely infected individuals, as well as laboratory strains, were assayed for their ability to replicate in primary adult microglial cultures and in MDM. Most of the isolates replicated equally well in both microglia and MDM, but several isolates replicated preferentially in one of the two cell types, differing by as much as 40-fold in p24gag production. This indicated that while MDM and microglial tropism overlap, a subset of isolates is particularly tropic for one of the two cell types. One isolate was further adapted to microglia by 15 sequential passages, raising the peak p24 concentration produced by 1,000-fold. In addition, the passaged virus induced marked cytopathologic changes (vacuolization and syncytium formation) in infected microglial cultures. Sequence comparison of the V3 loop of unpassaged and multiply passaged virus revealed amino acid changes shown to be associated with isolates from patients with HIV dementia. Our data support the hypothesis that HIV-1 infection can be established in the central nervous system by viruses present early in HIV infection, that some of these viruses are particularly tropic for microglia, and that adaptation in this cell type can result in the selection of a pool of predominantly microglia-tropic (neurotropic) viruses.

Adult

[Clinical presentation of primary cytomegalovirus infection in a non-immunodepressed adult].

In the immunocompromised patients and during foetal life an acute infection due to the cytomegalovirus (CMV) causes great morbidity. In adults without predisposing factors the acute infection with CMV is rarely symptomatic, but can also provoke fever, fatigue, headache and anorexia for weeks. The peripheral blood smear shows big atypical lymphocytes within a relative lymphocytosis. The suspicion of the CMV infection is confirmed by the serological evidence of IgM anti-CMV antibodies. There is no etiological treatment, the evolution is spontaneously favorable most of the time. Establishing the diagnosis is reassuring for the patient and for the physician and avoids unnecessary analyses and treatments. We describe a series of 11 adults without predisposing factors who contracted an acute cytomegalovirus infection.

Adult

[Primary HIV infection: an often suspected diagnosis but confirmed late].

We report the history and clinical findings in 17 patients with primary HIV infection (PHI) diagnosed in the first 6 months of 1994. 9 of these patients were infected through heterosexual contacts, 5 were women with, as the only risk factor, sexual contacts with infected men. 10 of the 17 patients were symptomatic and the diagnosis of PHI was suspected in 8 of these patients at their first medical visit. However, the laboratory investigations were incomplete since p24 Ag was only requested for one patient and this led to a delay in diagnosis. Sera collected at the time of the first medical visit were available for 4 symptomatic patients, and in all of them p24 Ag was detected in the absence of HIV specific antibodies. These data underline the frequent occurrence of HIV transmission by the heterosexual route and the need to search for both specific antibodies and p24 Ag at the time of PHI.

AIDS Serodiagnosis

Growth-deficient mycobacteria in patients with AIDS: diagnosis by analysis of DNA amplified from blood or tissue.

Amplification and sequencing of mycobacterial ribosomal RNA genes (16S rDNA) may permit the detection of growth-deficient species (i.e., those exhibiting no growth or those whose growth is delayed for more than 12 weeks). Of blood samples from 26 patients with AIDS and a liver sample from one additional AIDS patient, three samples (two of blood and the one of liver) were positive by polymerase chain reaction only; cultures of these three samples remained negative for more than 12 weeks. Analysis of amplified 16S rDNA from blood revealed a sequence characteristic of Mycobacterium genavense in the first case, in which one of many previous blood cultures had also been positive for M. genavense. The sequences found in the second and third cases were characteristic of Mycobacterium avium. The sample from the second patient was a liver biopsy specimen in which acid-fast bacilli were visualized; the culture of this specimen yielded M. avium after 7 months. The third sample was a blood sample from a patient in whom a relapse of treated M. avium infection was suspected. These results indicate that amplification and sequencing of mycobacterial 16S rDNA may permit early diagnosis and provide a rationale for treatment of infections due to growth-deficient mycobacteria.

Acquired Immunodeficiency Syndrome

Foscarnet decreases human immunodeficiency virus RNA.

Foscarnet inhibits human immunodeficiency virus (HIV) replication in vitro and decreases p24 antigenemia in patients with cytomegalovirus (CMV) retinitis. To evaluate the effect of foscarnet on HIV replication, HIV RNA was quantitated in 17 patients before and during foscarnet therapy. Fifteen patients had CMV retinitis, 1 had CMV encephalitis, and 1 had intractable zoster. A decrease in HIV RNA was observed in 16 of 17 patients. Before the introduction of foscarnet, mean HIV RNA was 5.82 +/- 0.24 log RNA/mL and, after a median of 13 days of therapy, mean HIV RNA was 5.30 +/- 0.27 log RNA/mL (P < .001). Among patients with detectable p24 antigen at baseline, a significant decrease was observed (P = .017). This decrease in HIV RNA demonstrates that foscarnet is a potent antiretroviral drug.

AIDS-Related Opportunistic Infections

V3 sequences in primary HIV-1 infection.

OBJECTIVE: To determine HIV-1 genomic RNA and proviral DNA sequences of the third hypervariable region (V3 loop) of the envelope protein in patients with primary HIV-1 infection (PHI), and to compare these sequences with sequences from patients with more advanced HIV-1 infection. METHODS: Sera and peripheral blood mononuclear cells were collected from 24 patients with PHI living in Geneva. V3 sequences were determined using direct solid-phase sequencing on polymerase chain reaction (PCR) products. RESULTS: A 100% homology rate was observed between HIV-1 genomic RNA and proviral DNA paired nucleotide sequences from the V3 region in the 24 patients. Using a limiting dilution approach for three patients, a unique V3 sequence was observed for the genomic RNA. Three out of 24 amino-acid sequences presented the characteristic signature sequence QRGPGR, first described for the HIV-1LAI isolate, which is associated with lymphocytotropism. These three isolates also presented, for the V3 loop, a characteristic elevated charge (8) at physiological pH in comparison with the other isolates (3-5). There was no significant difference in the distribution of amino acids between the 24 V3 loop sequences from patients with PHI and 245 V3 loop sequences of the B subtype determined in patients with more advanced HIV-1 infection. CONCLUSION: The paired sequences recovered from HIV-1 genomic RNA and proviral DNA are identical for each of the 24 patients with PHI. Three isolates had the V3 loop characteristic signature sequence QRGPGR first described for the HIV-1LAI isolate. There is no characteristic V3 loop pattern associated with PHI isolates.

Adult

Laparoscopic assisted vaginal hysterectomy: an audit plus a word of caution.

Laparoscopic assisted vaginal hysterectomy (LAVH) performed in 109 cases has been reviewed. In this series the mean operative time was 89 minutes and mean inpatient hospitalization was 3.7 days. Throughout the review, 6 patients were considered to have major complications and each is discussed. The association of previous caesarean section and bladder damage is noted. LAVH widens the indications available for vaginal hysterectomy in younger women in whom the abdominal approach would previously be indicated, but extra caution is advised when this technique is first introduced to a gynaecological service.

Adult

Response of HIV RNA to didanosine as a predictive marker of survival.

OBJECTIVE: To evaluate whether early changes in viraemia in response to didanosine (ddI) predict death and occurrence of new AIDS-defining events. METHODS: Forty-three patients were followed during ddI treatment with sequential determinations of serum viraemia, mutations associated with drug resistance, CD4 counts and clinical evaluation. Patients were stratified into two groups of equal size, responders and nonresponders, using the median of individual changes in viraemia 1 month after initiation of ddI therapy. RESULTS: After 1 month of ddI, mean viraemia decreased by 0.35 log RNA copies/ml of serum (P < 0.001) in the population. A significant difference in survival (median, 14 and 35 months in nonresponders and responders, respectively; log rank, P = 0.004) and in the delay to the occurrence of new AIDS-defining events (median, 8 and 33 months in nonresponders and responders, respectively; log rank, P = 0.018) was observed. After stratification for presence of AIDS before starting ddI, viraemia response at 1 month remained predictive of both overall and AIDS-defining event-free survival (log rank, P = 0.0006 and P = 0.01). After a similar stratification for initial CD4, viraemia response still predicted overall survival (log rank, P = 0.009), but its predictive value for AIDS-defining event-free survival did not reach statistical significance (P = 0.12). High initial levels of HIV RNA, presence of mutation 215 or previous duration of zidovudine therapy were not predictive of survival. CONCLUSIONS: In patients treated with ddI, changes in viraemia at 1 month predict survival independently of initial AIDS diagnosis and initial CD4 counts.

Acquired Immunodeficiency Syndrome