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Biomedical subjects

F Leoncini

Publications and source records attributed to F Leoncini.

At least 19 recordsLinked to original sources
PubMed2000

Plasma viral load concentrations in women and men from different exposure categories and with known duration of HIV infection. I.CO.N.A. Study Group.

CONTEXT: According to recent studies, women have lower plasma HIV RNA concentrations than men. However, these studies did not take into account the duration of HIV infection. OBJECTIVES: To analyze the relationship between viral load and gender among individuals with known date of seroconversion. SETTING: Sixty infectious disease clinics in Italy. DESIGN: Cross-sectional analysis of data collected at enrollment in a cohort study. PARTICIPANTS: Injecting drug users and heterosexual contacts naive to antiretroviral therapy at enrollment (245 men; 170 women). MAIN OUTCOME MEASURES: Plasma HIV RNA concentrations, measured using quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) or signal amplification b-DNA assays before antiretroviral therapy. RESULTS: Plasma HIV RNA concentrations were similar by age and exposure category (p =.80 and p =.39, respectively). Median viral load among women was roughly half that of men (p =.002). The association between viral load and gender remained significant after fitting a two-way analysis of variance (p =.03) and after adjusting for CD4 count, modality of HIV transmission, and age at enrollment in a regression model. Viral load was 0.27 log10 copies/ml (95% confidence interval, 0.05-0.40; p =.01) lower in women (i.e., 50% lower in the raw scale). CONCLUSIONS: Plasma HIV RNA concentrations were found to be lower among women, even when considering the duration of HIV infection. Compared with men, it is possible women should be given highly aggressive antiretroviral therapy at lower HIV-RNA concentrations.

Adolescent↗
PubMed2000

Antiretroviral resistance mutations in human immunodeficiency virus type 1 reverse transcriptase and protease from paired cerebrospinal fluid and plasma samples.

Twenty-four adults infected with human immunodeficiency virus type 1 (HIV-1) with central nervous system symptoms were studied for antiretroviral resistance mutations in HIV-1 RNA obtained from paired cerebrospinal fluid (CSF) and plasma samples. Paired sequences were obtained from 21 and 13 patients for reverse transcriptase (RT) and for protease, respectively. Mutations conferring resistance to the RT inhibitors zidovudine, lamivudine, or nevirapine were detected in 14 patients, including 11 pretreated and 3 drug-naive subjects. The mutation patterns in the 2 compartments were different in most patients. Genotypic resistance to protease inhibitors was detected in both plasma and CSF from 1 patient treated with multiple protease inhibitors. However, accessory protease inhibitor resistance mutations at polymorphic sites were different in plasma and CSF in several patients. Partially independent evolution of viral quasispecies occurs in plasma and CSF, raising the possibility that compartmentalization of drug resistance may affect response to antiretroviral treatment.

Adult↗
PubMed2000

Strongyloides stercoralis: ultrastructural study of newly hatched larvae within human duodenal mucosa.

AIM: To investigate the ultrastructural features of the newly hatched larvae of Strongyloides stercoralis in human duodenal mucosa. METHODS: Duodenal biopsies from an AIDS patient were studied by transmission electron microscopy to investigate morphology, location, and host-worm relations of newly hatched larvae. RESULTS: Newly hatched larvae were found in the Lieberkuhn crypts within the tunnels formed by migration of parthenogenic females. Delimiting enterocytes were compressed. Release of larvae into the gut lumen was also documented. It was shown that both a thin and a thick membrane surrounded the eggs and larvae, as a tegument derived respectively from parasite and host. Segmentary spike-like waves, caused by contractures of worm body musculature, were observed on the surface of newly hatched larvae, and their intestinal lumen was closed and empty, with no budding microvilli. Immaturity of the cuticle and some degree immaturity of amphidial neurones were found, but there was no evidence of either immaturity or signs of damage to other structures. CONCLUSIONS: Newly hatched larvae of S stercoralis appear to be a non-feeding immature stage capable of active movement through the epithelium, causing mechanical damage. The tegument resulting from the thin and the thick membrane may protect the parasite and reduce any disadvantage caused by immaturity.

AIDS-Related Opportunistic Infections↗
PubMed2000

Blood viscosity and red cell morphology in subjects suffering from cirrhosis before and after treatment with S-adenosyl-L-methionine (SAM).

Alterations of fluidity of the hepatocytic membrane and of the transport related systems are the basis of the cholesteatic syndrome and favour the tissue accumulation of cytotoxic metabolites. S-Adenosyl-L-Methionine (SAM) is a natural molecule which acts as a giver of methylic groups and as an enzymatic activator in several enzymatic actions of transmethylase and of transulphuration and plays a key role in biochemical processes of hepatic cell. The aim of our study was to evaluate the effects of SAM on the restoration of the membrane fluidity and on the hepatic function in general. In studying the fluidity of the cell membrane we evaluated some hemorheological parameters (total blood viscosity and red cell morphology). Fluidity of the red cell membrane is one of the most important elements of red cell rheology. We studied 15 patients (Group A) suffering from micro- and macro-nodular cirrhosis verified through hepatic biopsy, with alcoholic or post-viral causes. We evaluated the values of: blood viscosity (with a cone-plate rheometer by Carri-med), haematocrit, plasma fibrinogen and the erythrocytic morphology at the optical microscope with the Zipursky-Forconi method before and after 7 days of therapy with SAM i.v.. Data were compared with those of a similar group (Group B) treated with traditional therapy only (hyposodic and hypoprotein diet supplemented with multivitamin preparations, vitamin K in particular, if necessary, and potassium sparing diuretics). We also measured biliary salts, alkaline phosphatase, transaminase and gamma-GT. In the first group we observed a statistically significant reduction of blood viscosity, haematocrit didn't change significantly; biliary salts reduced in a statistically significant way. Evaluation of red cell morphology showed in all cases a pathological percentage (>15%) of echinocytes and knizocytes which reduced to a mean of 5% after SAM therapy. We observed no further modifications of the other hemorheological parameters. Results demonstrate that SAM has a positive action on the fluidity of the membrane, as indicated by the improvement of haemorheological parameters and by the significant decrease of biliary salts, indicating the presence of cholesteasis.

Blood Viscosity↗
PubMed1999

A randomized, double-blind trial on the use of a triple combination including nevirapine, a nonnucleoside reverse transcriptase HIV inhibitor, in antiretroviral-naive patients with advanced disease.

The immunologic and virologic activity of nevirapine in combination with two nucleosides (zidovudine [ZDV] and didanosine [ddI]) was evaluated in antiretroviral-naive patients with a CD4 count <200/mm3 or clinical AIDS. In all, 68 patients were enrolled in a 48-week double-blind, placebo-controlled trial. A group of 32 patients received ZDV + ddI + nevirapine, and 36 patients received ZDV + ddI. Primary efficacy parameters were the activity on HIV-1 RNA and on peripheral blood CD4+ cells, with differences between groups analyzed by the Wilcoxon's nonparametric two-sample test. Baseline RNA was high in both treatment groups (median values, 5.8 and 5.7 log10). RNA and CD4 responses were significantly higher with the triple combination (median RNA reductions, 2.69 versus 1.05 log10 at 24 weeks and 1.97 versus 1.20 log10 at 48 weeks; median CD4 increases, 81 versus 64 cells/mm3 at 24 weeks and 101 versus 27 cells/mm3 at 48 weeks). This study demonstrates that a triple combination of ZDV + ddI + nevirapine used as first-line regimen in antiretroviral-naive patients can induce sustained virologic and immunologic response in patients with low CD4 count or a previous diagnosis of AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1999

Archetypal and rearranged sequences of human polyomavirus JC transcription control region in peripheral blood leukocytes and in cerebrospinal fluid.

Two forms of human polyomavirus JC (JCV) genome are known based upon the structure of the transcriptional control region (TCR) of the virus: the archetypal form, which is commonly detected in urine, and the rearranged form, which was first detected in brain tissue from progressive multifocal leukoencephalopathy (PML) patients. The latter actually includes a group of TCR variants that, relative to the former, are characterized by various deletions and/or duplications. The aim of this study was to establish whether or not a correlation exists among the TCR type, the spreading of the virus within the host and its ability to cause PML. JCV TCR sequences from peripheral blood leukocytes (PBL) and cerebrospinal fluid (CSF) obtained from various groups of patients were compared. JCV with archetypal TCR was detected in CSF and PBL specimens from patients without neurological disorders or who eventually received a diagnosis of a non-PML neurological disorder. Rearranged TCR sequences were detected in all the CSF and PBL specimens from PML patients. The high similarity observed between the TCR structure detected in PBL and CSF specimens from individual patients could strengthen the hypothesis that PBL has a role in spreading JCV to the brain. Moreover, heterogeneous TCR patterns have been shown in individual PBL specimens from PML patients. This supports the hypothesis that, in PBL, JCV may replicate and undergo rearrangements of the TCR. The detection of JCV DNA by PCR in CSF independently from PML, although rare, could suggest that this assay is not sufficient for a virological diagnosis of PML. Further studies are required to assess the usefulness of quantitative assays or TCR typing in combination with PCR for diagnostic purposes.

Base Sequence↗
PubMed1998

Persistent damage to Enterocytozoon bieneusi, with persistent symptomatic relief, after combined furazolidone and albendazole in AIDS patients.

AIM: To investigate morphological changes in Enterocytozoon bieneusi and the duration of symptomatic relief after combination treatment with furazolidone and albendazole in AIDS patients. METHODS: Four severely immunocompromised AIDS patients with symptomatic E bieneusi infection of the gut received an 18 day course of combined furazolidone and albendazole (500 + 800 mg daily). All patients were monitored for parasite shedding in stool by light microscopy at the end of treatment and monthly during follow up. At the end of treatment, duodenal biopsy specimens obtained from three patients were studied by transmission electron microscopy by two pathologists blind to the patients' treatment or clinical outcome. Duodenal biopsy specimens obtained from one of the patients two months after completion of treatment were also studied electronmicroscopically. RESULTS: All patients had long lasting symptomatic relief, with a major decrease--or transient absence--of spore shedding in stools from completion of treatment. After treatment, changes in faecal spores were persistently found by light microscopy in all cases, and there was evidence of both a substantial decrease in the parasite load and ultrastructural damage in the parasite in all biopsy specimens. The treatment was well tolerated, and no patient had clinical or parasitological relapse during follow up (up to 15 months). CONCLUSIONS: The long lasting symptomatic relief observed in all four treated patients correlated with the persistent decrease in parasite load both in tissue and in stool, and with the morphological changes observed in the life cycle of the protozoan. These data suggest that combined treatment with furazolidone and albendazole is active against E bieneusi and may result in lasting remission even in severely immunocompromised patients.

AIDS-Related Opportunistic Infections↗
PubMed1998

Chronic cryptosporidiosis in patients with AIDS: stable remission and possible eradication after long-term, low dose azithromycin.

AIMS: To investigate the effectiveness of long term, low dose azithromycin treatment for chronic cryptosporidiosis in patients with AIDS. METHODS: Azithromycin was administered as initial daily treatment to 13 patients with AIDS: 6 patients received 500 mg for 30 to 40 days (mean 35); 3 patients received 1000 mg for 21 to 50 days (mean 37); and 4 patients received 1500 mg for 20 days. Nine of the 13 patients were also given low dose maintenance treatment with different schedules of azithromycin for 30 to 360 days (mean 129). Patients were monitored, during and after treatment, for parasite shedding in stool and for daily stool frequency and body weight. All but one patient had severe immunodeficiency. RESULTS: Long term, low dose maintenance treatment was associated with major clinical and parasitological benefits: there was probable eradication of infection in 2 patients, and 7 patients showed a complete response with persistent high decrease (5 patients) or clearance (2 patients) of parasite in stool. The drug was well tolerated, and there was no relapse either during treatment or during follow up (up to 21 months). These results were more impressive than those observed after the short term initial course of azithromycin, which was unable at any tested dose to achieve parasite clearance in stool (except in the patient with less advanced immunodeficiency) or to prevent relapse in 3 patients who discontinued treatment. Reversible side effects occurred with the 1500 mg daily dose. CONCLUSIONS: Long term, low dose azithromycin is well tolerated and may induce stable remission of chronic cryptosporidiosis in patients with AIDS. It may lead to probable eradication of the infection in some patients, even those with severe immunodeficiency.

AIDS-Related Opportunistic Infections↗
PubMed1998

Evaluation of erythrocyte morphology as deformability index in patients suffering from vascular diseases, with or without diabetes mellitus: correlation with blood viscosity and intra-erythrocytic calcium.

The aim of our study was to evaluate the erythrocytic morphology in vascular patients, with or without diabetes, showing cell alterations correlated to blood viscosity and intra-erythrocytic calcium. We studied 108 subjects: 20 normal subjects, 58 vascular patients (25 suffering from CHD, 19 from CVD, 14 from POAD) and 30 non-insulin-dependent diabetes patients with vascular disease in metabolic compensation (13 CHD, 9 CVD, 8 POAD). Erythrocytic morphology, blood viscosity and intra-erythrocytic calcium were evaluated. Our results show that bowls, the most deformable red cells, decreased significantly in vascular patients and in POAD diabetics, while the discocytes, having a stiffer form, greatly increased in subjects suffering from ischemic disease and in POAD diabetics. The altered red cells (echinocytes and knizocytes) reached a statistical significance in CVD and POAD diabetics. Comparing the percentage of discocytes to intraerythrocytic calcium content in vasculopathic subjects, we obtained a significant correlation. No evidence of a relationship between discocytes and blood viscosity was found, even if blood viscosity significantly increased in patients affected by ischemic disease. These results suggest that ischemia decreases the deformability of red cells which is supported by the study of red cells morphology, by the erythrocytic morphology index (EMI), which becomes < 1, and by the evaluation of cytosolic calcium content.

Adult↗
PubMed1997

Enterocytozoon bieneusi in AIDS: symptomatic relief and parasite changes after furazolidone.

AIMS: To investigate changes in morphology of the developmental stages of Enterocytozoon bieneusi and symptomatic relief observed in AIDS patients after treatment with furazolidone. METHODS: Six AIDS patients with symptomatic E bieneusi infection of the small intestine were treated with a course of furazolidone. All patients had a weekly monitoring of parasite shedding in stool by light microscopy during and after treatment. At the end of the treatment, duodenal biopsy specimens obtained from three patients were studied by transmission electron microscopy by two pathologists who were unaware of the patients' treatment. RESULTS: All patients showed both clinical and parasitological response with transient clearance or decrease of spore shedding in stool. After treatment, alterations in faecal spores were observed in all patients by light microscopy, and ultrastructural changes in E bieneusi at all stages of the life cycle were demonstrated in biopsy specimens of the three patients who underwent post-treatment endoscopy. CONCLUSIONS: The clinical benefit seen after treatment with furazolidone in six AIDS patients with E bieneusi intestinal infection may be due to damage to the developmental stages causing a partial inhibition to reproduction of the parasite.

AIDS-Related Opportunistic Infections↗
PubMed1997

Chronic intestinal infection due to subgenus F type 40 adenovirus in a patient with AIDS.

A case of chronic intestinal infection due to adenovirus type 40 lasting for 13 months in a patient with AIDS is described. Adenovirus particles were detected by electron microscopy in biopsy samples taken from the duodenum 3 months after the onset of diarrhoea. The virus was identified as adenovirus type 40 in stool samples by ELISA monoclonal antibodies to adenovirus group antigen (MAd-g2) and types 40 and 41 (MA 40-1 and MA 41-1). No other enteropathogens were found. These data support a causal relationship between adenovirus 40 and the gastrointestinal symptoms of the patient. This is the first reported case of intestinal infection caused by adenovirus type 40 in a patient with AIDS.

AIDS-Related Opportunistic Infections↗
PubMed1997

[Azithromycin combined with pyrimethamine in the treatment of neurotoxoplasmosis, in an AIDS patient].

We report one case of successful treatment of cerebral toxoplasmosis in acquired immunodeficiency syndrome (AIDS) with azithromycin combined with pyrimethamine. Toxoplasmic encephalitis had been diagnosed on the basis of multiple lesions exhibiting ring like contrast enhancement on double contrast Computed Tomographic (CT) scan of the brain. Thereby our patient had been treated with pyrimethamine 25 mg/die, after an attack dose of 100 mg in the first day, and clindamycin 2400 mg/die, because of sulfa-drug allergy, but clindamycin had to be discontinued because of rash development. At this point azithromycin, at a dose of 1000 mg/die for 21 days and 1500 mg a week for the following 50 days of follow-up, was added to pyrimethamine. Follow-up CT scan after 20 days of treatment (10 with clindamycin+pyrimethamine and 10 with azithromycin+pyrimethamine) revealed partial resolution of the brain lesions and subsequently (after 50 and 80 days of treatment) complete resolution.

AIDS-Related Opportunistic Infections↗