Biomedical subjects
Publications and source records attributed to A Benedetto.
Explore the source record for details and available documents.
Cell proliferation and differentiation in the vomeronasal organ of the adult mouse was studied by bromodeoxyuridine (BrdU) immunohistochemistry coupled to immunostaining for specific markers of the differentiation, such as carnosine, B50-GAP43 (growth-associated protein) and stathmin. The present study shows that three populations of proliferating elements are present in the vomeronasal sensory epithelium that are placed, respectively, in the supporting cell layer, at the boundaries between the sensory epithelium (S-VNO) and the non-sensory (NS-VNO) and in the basal region of the S-VNO. The number of dividing cells at the boundaries of the S-VNO is by far prevailing. Few proliferating cells located adjacent to the basal membrane are, however, present 1 day after BrdU inoculations. Seven days after BrdU treatment immunopositive nuclei were detected in more central regions of the VNO and at longer survival times they were also positive to carnosine, a marker of fully differentiated neurons. In conclusion, the present results suggest that at least two populations of VNO neuronal precursors are responsible for cell replacement throughout life.
OBJECTIVES: To determine whether highly active antiretroviral therapy (HAART) is effective in HIV-associated neurocognitive impairment. DESIGN: An open label, prospective, observational study. METHODS: Since April 1996, 116 patients with advanced HIV infection, reverse transcriptase inhibitor (nRTI) experienced but protease inhibitor (PI) naive, were screened for the presence of neurocognitive impairment. Ninety patients with confounding neurological illness, opportunistic infections or drug abuse were excluded. The remaining 26 patients underwent comprehensive neuropsychological testing, and laboratory measures before, after 6 and after 15 months of treatment with one PI plus two nRTI. RESULTS: The prevalence of neurocognitive impairment decreased from 80.8% (baseline) to 50.0% (P<0.05) (sixth month) and to 21.7% (P<0.001) (15th month). Among the functions explored, the impairment of concentration and speed of mental processing decreased from 65.4 to 21.7% (P<0.01) and of memory impairment from 50 to 8.7% (P<0.01). Comparing baseline with the sixth and 15th month raw scores, a statistically significant improvement was seen in measures exploring concentration and speed of mental processing (P<0.05), mental flexibility (P<0.05), memory (P<0.05), fine motor functions (P<0.05) and visuospatial and constructional abilities (P<0.01). After 6 months of HAART patients with a normal neuropsychological examination had lower mean plasma viraemia (2.95 versus 3.97 log copies/ml, P<0.05) and greater mean log plasma HIV RNA changes from baseline (-1.84 versus -0.83 log copies/ml, P<0.05) than neuropsychologically impaired subjects. CONCLUSION: HAART produces a positive and sustained effect on neurocognitive impairment in HIV-infected patients. A reduction of plasma viral load was associated with the regression of neuropsychological test abnormalities.
In this study, the susceptibility of mature human oocytes to HIV-1 infection has been investigated. We exposed in vitro human oocytes of healthy women using inocula of cell-free HIV-1. We also tested for the presence of HIV-1-specific receptor molecules on the surface of these cells. By applying polymerase chain reaction (PCR) analysis, transmission electron microscopy (TEM), and immunocytochemistry at both light and electron microscopic levels, we did not obtain evidence for HIV DNA production nor for oocyte-associated HIV particles. Experiments of immunostaining for CD4, CCR5, and GalAAG (putative receptor for HIV in sperm), as well as reverse transcriptase (RT)-PCR for CD4, CCR5, and CXCR4, which all suggested the absence of the mentioned receptors in mature oocytes and in follicular cells. This study fills an important gap concerning the information available on the direct HIV infection of human gametes, adds to our basic understanding of HIV infection in human oocytes, provides different results from those obtained with human spermatozoa using comparable methods, and provides a basic contribution to the investigation on HIV infection in human oocytes.
Differential cell proliferation and apoptosis play a key role in organ morphogenesis. We have analyzed these two processes in the development of murine vomeronasal organ (VNO), an olfactory structure involved in the detection of pheromones. Using the TUNEL (TdT-mediated dUTP nick end labelling) method we demonstrate that dying cells are relatively more abundant in non sensory vomeronasal organ (NS-VNO) rather than in sensory epithelium (S-VNO), particularly in early stages of development. During ontogeny cell proliferation, studied with bromodeoxyuridine (BrdU) labelling, shows a broad pattern of localization, since proliferating cells are distributed throughout the VNO and not confined between NS-VNO and S-VNO. Quantification of BrdU-labelled cells indicates that proliferation is rather stable in both components.
A series of chemically oversulphated galactosaminoglycans (SO3H:COOH ratio > or = 2) were tested in vitro as antiviral agents against human immunodeficiency virus type 1 (HIV-1), the aetiological agent of AIDS, and against herpes simplex virus type 1 and human cytomegalovirus, two agents responsible for opportunistic infections in HIV-infected people. The oversulphated derivatives displayed an increase in activity ranging from one to four orders of magnitude against the three viruses, as compared to the natural parent compounds (SO3H:COOH, ratio approx. 1). The antiviral activity of these polyanions appears to be favoured by a high degree of sulphation and a high molecular mass. An oversulphated dermatan, with a SO3H:COOH ratio of 2.86 and molecular mass of 23.2 kDa, was the most potent anti-HIV-1 compound (EC50 0.04 microgram/ml). A second oversulphated dermatan, with a SO3H:COOH ratio of 2.40 and molecular mass of 25 kDa, displayed the highest activity against HSV-1 (EC50 0.01 microgram/ml). An oversulphated chondroitin, with a SO3H:COOH ratio of 2.80 and molecular mass of 17.3 kDa, was the strongest anti-HCMV agent (EC50 0.4 microgram/ml). In view of the absence of the side-effects typical of heparin-like compounds, a combination of these derivatives could have therapeutic potential.
The debate about the presence of HIV-1 particles in human gametes and recent experimental results are reported in detail. Using immunocytochemistry, in situ hybridization at electron microscopy level, polymerase chain reaction and in vitro fertilization, it has been demonstrated that human spermatozoa can incorporate HIV-1 using special receptors, different from the usual CD4, and that they remain active and able to vehicle the viral particles into the oocyte, which is regularly fertilized. Moreover, by transmission electron microscopy (TEM), immunocytochemistry and PCR, we demonstrated that cell-free HIV-1 is not able to bind and penetrate the human oocyte in vitro. We attribute this behaviour to the fact that the oocyte and cumulus cells are devoid both of GalAAG and of CD4 receptors. PCR analysis indicated that mRNAs specific for CD4, CXCR4 and CCR5 proteins were absent, too.
Risk factors for cervical infection with human papillomavirus (HPV) were assessed among 236 Italian women at risk for human immunodeficiency virus (HIV) infection (intravenous drug users (IVDU) or sexual partners of males at risk for HIV infection). All study participants underwent a structured interview, determination of HIV serostatus and detection of HPV cervical infection by means of polymerase chain reaction (PCR). Overall, the cervical presence of HPV DNA was ascertained in 86 of these 236 women (36.4%), while squamous intraepithelial lesions (SIL) were diagnosed in 57 (24.1%). HPV-infected and non-infected women did not differ in age, education and cigarette smoking. A statistically significant trend in the risk of HPV infection with increasing number of lifetime sexual partners was noted (P = 0.01), but such trend was attenuated in multivariate analysis (multiple logistic regression (MLR) odds ratio (OR) for > or = 20 partners vs 1 = 1.6, 95% confidence intervals (CI): 0.4-5.9). A nearly threefold higher risk of HPV cervical infection emerged among IVDU women (MLR-OR: 2.7, 95% CI: 1.4-5.0), and this difference was not influenced by HIV serostatus. The prevalence of HIV infection was higher among HPV-positive than HPV-negative women (62.8% and 54.0%, respectively) (MLR-OR = 1.9, 95% CI: 0.9-3.8), and the proportion of women with less than 200 CD4+ cells/mm3 was slightly and not significantly higher among HPV-positive (47.1%) than negative women (37.2%).
We have been investigating a long-term nonprogressor who was found to be human immunodeficiency virus type 1 (HIV-1) seropositive in 1985 and has survived with stable CD4+ T-cell counts (>1,000 CD4 cells/microl) without any AIDS-related illness. We have previously reported that repeated attempts to measure HIV-1 RNA in the peripheral mononuclear cells obtained from this subject have invariably failed. In the present study, we have analyzed the molecular nature of the HIV-1 quasispecies infecting this patient by PCR amplification of two proviral regions, the 5' long terminal repeat (5'LTR)/gag leader and the nef gene, directly from fresh uncultured peripheral mononuclear cells, followed by length polymorphism analysis (with 1994, 1995, and 1996 samples) and sequencing (with a 1996 sample). Only proviral forms with nef deletions were revealed by length polymorphism analysis in samples from all three time points. Sequence analysis of the nef gene from the 1996 sample confirmed the presence of similar proviral quasispecies characterized by the presence of several deletions located in the nef-alone and the nef/U3 overlapping regions. Length polymorphism analysis of the 5'LTR/gag leader region suggested the existence of two major quasispecies populations, one characterized by the presence of forms carrying deletions in the U3 region and the other showing a completely intact, full-length 5'LTR. Evidence of the role of nef gene defects in long-term survival of HIV-1-infected patients has been provided so far in two independent investigations involving patients infected with HIV through blood transfusion. Here we show the existence of a similar condition in a subject who acquired HIV-1 seropositivity through the sexual route.
We assessed the association between different HPV genotypes, HIV infection, and cervical squamous intra-epithelial lesions (SIL) in 236 women with known HIV serostatus enrolled in a longitudinal multicentric study in Italy. Of these women, 135 were HIV-infected, and were not markedly different from HIV-negative women with regard to demographic characteristics, sexual practices, smoking, or intravenous drug use. We obtained 232 cervical smears suitable for cytological examination and HPV-genotype analysis (134 from HIV-positive women and 98 from HIV-negative women). For 86 HIV-positive and 89 HIV-negative women, the smears appeared normal at cytomorphological analysis. Cytological dysplasia of varying degrees was detected in 48 smears from HIV-positive women and in 9 from HIV-negative women. HPV prevalence, assessed using polymerase-chain-reaction analysis, did not significantly differ between HIV-positive and HIV-negative women. The prevalence of HPV-associated SIL was much greater among HIV-infected women. The most frequently detected genotypes in both groups were HPV 16 and HPV 18. The prevalence of HPV 16 among HIV-positive women was similar to that for HIV-negative women; this was also true for HPV 18. However, in the HIV-positive group, most of these genotypes were associated with SIL. HIV-positive women showed a wider spectrum of genotypes, including non-oncogenic and rare types. An association between SIL and HIV infection was confirmed for all HPV genotype classes.
This study aimed to identify risk factors for squamous intraepithelial lesions (SIL) in women with known HIV status and to explore the association between SIL, HPV subtype, and HIV-induced immunosuppression. The study population consisted of women with known HIV serological status who were attending a network of 16 clinical centres in Italy. Detailed behavioural data, clinical and laboratory parameters, and samples for diagnosis of SIL by Papanicolau smear and HPV infection using a polymerase chain reaction (PCR) were obtained from each study participant. The strength of the association between SIL and possible risk factors was assessed calculating crude and adjusted odds ratios derived from univariate analysis and multivariate models. We enrolled 236 women, of whom 135 (57.2%) were HIV-infected. SIL was diagnosed in 57 women (24.1%); of these, 48 (35.6%) were HIV-infected and 9 (8.9%) were HIV-negative. HPV-DNA was detected in 41 (72%) women with SIL and in 45 (25%) women without SIL. HPV-DNA was more often detected among HIV-infected women than among HIV-negative women (40% vs. 32%), but the difference was not statistically significant. Women infected with high-risk types or with low-risk-uncharacterised types of HPV both had a higher risk of SIL compared with HPV-negative women (respectively, AOR: 17.53 and AOR: 2.89). HIV-infected women with severe or moderate immunosuppression were more likely to have SIL than HIV-negative women (respectively, AOR: 7.29 and AOR: 3.09) also independently from HPV infection. Women reporting use of a contraceptive pill had a 2.5 times higher risk of SIL compared with those who never used hormonal contraceptives. The results confirm that high-risk HPV types are strongly associated with SIL, and that HIV infection may strengthen the effect of HPV at cervical level. The use of oral contraceptives may slightly increase the risk of SIL in women with at-risk behaviour for HIV infection.
OBJECTIVES: We investigated a selected group of 11 non-progressor, HIV-infected individuals 20 months prior to this study and found that they all had undetectable levels of viral RNA expression in their peripheral blood lymphocytes (PBL). Phorbol 12-myristate 13-acetate (PMA) and phytohaemagglutinin (PHA) stimulation of PBL produced easily detectable amounts of HIV RNA in only two out of five of these patients. Here we report the results of the virological and clinical follow-up of nine non-progressors from this group. We verified the stability of their non-progressive status and attempted to correlate it to specific virological markers. METHODS: Proviral DNA in lymphocytes was tested by semi-quantitative polymerase chain reaction (PCR). Detection of unspliced (US) and multiple spliced (MS) HIV RNA species in unstimulated and stimulated lymphocytes was performed by reverse transcriptase-PCR (RT-PCR). The amount of p24 antigen released into the media of lymphocyte cultures was measured using a standard procedure. Lymphocyte populations were depleted of CD8 cells by immunomagnetic purging. RESULTS: Follow-up of nine of these subjects showed that the patients who previously showed viral RNA activation following lymphocyte stimulation in vitro, developed a clinical and immunological progression characterized by CD4 count decline and lymphadenopathy. In contrast, all the other subjects maintained progression-free status throughout the follow-up period, with no detectable levels of HIV RNA in the PBL. Notably, this group of subjects showed no activation of viral RNA expression following stimulation of either undepleted or CD8-depleted lymphocytes in vitro. CONCLUSION: The group of non-progressors studied was found to be heterogeneous regarding the stability of the non-progressive status during the follow-up period. Our results suggest that the activation of HIV RNA expression following PMA-PHA treatment of lymphocytes in vitro is an early marker for future progression of the disease.
Cutaneous polyarteritis nodosa is a benign form of the disease with cutaneous involvement and occasional systemic manifestations. We report a 51 years old man presenting with malaise, arthralgia, myalgia and nodular, erythematous and painful skin lesions in both legs. The pathological study of these lesions showed a polyarteritis. During hospital stay there was a mild remission of the disease without treatment, but its reappearance during follow lead to the use of prednisone.
The HIV viral burden and RNA expression in a selected group of infected, clinically non-progressor patients were investigated. Five fast-progressor patients and 10 AIDS cases were included as controls. The HIV viral load was investigated by semiquantitative polymerase chain reaction (PCR) in adherent macrophages and in genomic and extragenomic fractions of lymphocytes. HIV DNA was not found in macrophages in the non-progressor subjects, was weakly positive in 2 of 5 fast-progressors and strongly positive in most of the AIDS patients. The number of HIV proviruses found in lymphocytes of the non-progressor subjects varied from 5 to 160 copies/microgram DNA, values ten times lower than those recorded in fast-progressors and AIDS patients. The extragenomic HIV DNA (2 LTR forms) was absent or barely detectable in the lymphocytes from non-progressors and abundant in the other groups. HIV RNA was not found in the lymphocytes of all non-progressors. This may indicate that a latent state of HIV provirus exists in the lymphocytes of these subjects. To investigate this point, cultivation and stimulation with PHA (phytohemoagglutinin) and PMA (phorbol 12-myristate 13-acetate) of lymphocytes from these subjects were attempted but after 6 days HIV RNA (RT-PCR for gag region) was still absent or barely detectable in these patients. There are no other reports of the absence of HIV provirus induction in lymphocytes from infected individuals. If confirmed in a larger number of patients, such non-inducibility might serve as a predictor marker of progression of the disease.
Three types of open ansa-chain rifamycin S derivatives have been prepared: derivatives with the ansa-chain open at C(29) and the original dihydrofuranone ring; derivatives with the ansa-chain open at C(29) and a furane ring; derivatives with the ansa-chain at open NH-C(15). Only derivatives of the first type are weak inhibitors of HIV-1 reverse transcriptase (IC50 ca.300 microM) while derivatives of the two other types are inactive. It has been hypothesized that the active derivatives inhibit the viral enzyme interacting through the groups C(14)H3, C(13)H3, and C(1)O at the same site as the well-known inhibitors TIBO and Nevirapine. In particular C(13)H3 must be unhindered and in an appropriate position out of the plane containing the chromophore-rings. The open ansa-chain seems to play the role of a lipophylic substituent.
An anonymous unlinked seroprevalence study of human immunodeficiency virus (HIV) infection was performed by testing pools of ten sera remaining from specimens submitted consecutively to clinical pathology laboratories at 18 Italian public hospitals during four consecutive days in April 1991. Sera from positive pools were retested individually by three different enzyme immunoassays (EIAs) and considered positive if reactive by all three assays. Only the sera with discordant EIA results were retested by Western blot. Of a total of 22,590 sera, 278 were HIV positive (1.2%). The highest rates were seen in hospitals located in metropolitan areas (1.5%), in infectious disease departments (28%) and in drug addiction treatment units (28%); among men aged 21-30 (4.6%) and 31-40 years (4%); and among women aged 21-30 years (1.6%). The distribution of seropositive patients by gender and age group suggests an increasing role of heterosexual transmissions of the infection. The presence of anti-HIV antibodies in sera from patients of both sexes, in all age groups, and from all clinical settings reinforces the need for health care workers to adhere to universal precautions issued to prevent occupational bloodborne infections.
By immunocytochemistry and in situ hybridization at the electron microscopy level, and by the PCR technique, we have shown that HIV-1 binds and enters normal sperm; that viral particles, their antigens, and nucleic acid are present in sperm from HIV-1 infected men; and that such sperm can transfer HIV-1 like particles to normal human oocytes. We also present evidence that a galactosylceramide-like compound is present on the sperm membrane and could function as an alternative receptor for HIV.
Explore the source record for details and available documents.