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G Pecoraro

Publications and source records attributed to G Pecoraro.

At least 19 recordsLinked to original sources
PubMed2004

Severe acute colitis associated with CMV: a prevalence study.

BACKGROUND: Cytomegalovirus has been identified as a pathogen that contributes to flares of colitis when detected in colonic specimens of patients with inflammatory bowel disease. AIM: To determine the overall prevalence and the role of cytomegalovirus infection in a consecutive series of patients with acute severe colitis admitted to our department from 2000 to 2003. METHODS: Among 42 patients (38 with ulcerative colitis and 4 with Crohn's disease) admitted to our hospital for acute severe colitis, we performed proctoscopy and biopsy together with blood sample for cytomegalovirus determination at the time of admission, regardless of their steroid resistance. RESULTS: In the 42 patients, we discovered an overall cytomegalovirus infection prevalence of 21.4% (9/42) in our geographical area. In seven patients (16.6%), cytomegalovirus was detected through biopsy. The presence of cytomegalovirus in biopsies was not always predictive of steroid resistance. Three patients with cytomegalovirus in biopsies responded to conventional treatment without needing any antiviral treatment, which suggests that the virus plays only an incidental role. CONCLUSIONS: Cytomegalovirus is frequently associated with colitis but it is not always pathogenic. Studies on the genotyping of the virus might explain the diversity of its biological behaviour.

Adult↗
PubMed2001

Prevalence of cytomegalovirus infection in severe refractory ulcerative and Crohn's colitis.

OBJECTIVES: Cytomegalovirus infection has been reported as a cause of refractory inflammatory bowel disease, but no data are available on its prevalence in severe colitis. The aim of this study was to evaluate the prevalence and outcome of cytomegalovirus infection in a consecutive series of patients with severe steroid refractory colitis admitted to our department from 1997 to 1999. METHODS: Among 62 patients with severe colitis, 55 with ulcerative colitis and seven with Crohn's disease, 19 (30%) were resistant to intravenous steroids and bowel rest. In all of them, rectal biopsies were examined for cytomegalovirus (the flexible proctoscopy being performed without air insufflation and limited to the first 10 cm). Buffy coat preparation on leukocytes was also performed to detect systemic infection. If cytomegalovirus was not detected, cyclosporine was started. RESULTS: In seven (five with ulcerative colitis and two with Crohn's disease) out of 19 (36%) patients with refractory disease, cytomegalovirus was diagnosed in the rectal specimens as well as by buffy coat preparation. Five patients went into remission after antiviral treatment (three with ganciclovir and two with foscarnet). One patient did not respond and was operated on. In one patient, cytomegalovirus was found in the surgical specimen. CONCLUSIONS: Cytomegalovirus infection is a frequent cause of severe refractory colitis. Rectal biopsy should always be performed in severe steroid-resistant colitis.

Adult↗
PubMed1994

[Cystic hygroma: 2 case reports and review of the literature].

Cystic hygroma, an infrequent malformation of the lymphatic system (5 cases per 1000 abortions with CRL greater than 3 cm), was observed in 2 cases which prompted the present study. The Authors also present a brief review of the literature on this topic. After reviewing the hypothetic pathogenesis of the lymphatic obstruction which underlines this pathology, the paper focuses on the association of hygroma and anatomical and chromosomic alterations. The various anatomopathological and echographical findings are then described. Special attention is drawn to the diagnosis of cystic hygroma, after which the two case studies are illustrated. The prognosis of this pathology is pessimistic and the patient and specialist have to choose between immediate abortion or waiting for the inevitable outcome of gestation.

Adult↗
PubMed1993

Genetic analysis of in vitro progression of human papillomavirus-transfected human cervical cells.

The authors have established an in vitro model system which demonstrates the progression of the transformed phenotypes of human cervical epithelial cells transfected with human papillomavirus (HPV) type 16 and 18 DNAs. Both viral DNAs exhibit immortalizing potential; however, only HPV 18-immortalized cell lines progress to exhibit anchorage-independent growth and, in a limited number of cases, tumorigenesis. In this paper, the authors have examined the genetic basis for this in vitro progression step by step, including immortalization, anchorage-independent growth, and tumorigenicity of the HPV-transfected human cervical epithelial cells by cell fusion. The results suggest that (a) all three transformed phenotypes, i.e., immortalization, anchorage-independent growth, and tumorigenesis, in this in vitro cervical carcinogenesis model are a result of recessive changes in genes or processes involved; (b) inactivation of p53 and retinoblastoma protein is not sufficient for immortalization of human cervical epithelial cells; (c) HPV expression per se does not account for immortalization of human cervical epithelial cells; (d) immortalization of human cervical epithelial cells initiated by HPV can occur through different processes, although one of them is the most preferred; and (e) probably only one group of recessive genes appears to be involved in the loss of anchorage-dependent growth for HPV-immortalized human cervical cells.

Base Sequence↗
PubMed1992

Transformation by human papillomavirus type 16 (HPV16) DNA but not HPV6b DNA is enhanced by addition of the human cytomegalovirus enhancer.

Primary human cervical epithelial cells immortalized by human papillomavirus type 16 (HPV16) DNA exhibit altered morphology and differentiation characteristic of transformation, but show a lack of transformed phenotype relative to HPV18 DNA immortalized cells in terms of anchorage-independent growth (Pecoraro, Lee, Morgan, and Defendi, 1991, Am. J. Pathol. 138, 1-8). This is completely corrected by inserting a strong heterologous enhancer derived from human cytomegalovirus DNA upstream from the HPV16 long control region. The cells immortalized by this DNA form colonies in agar comparable to those formed by HPV18 DNA immortalized cells. The enhanced transformation capability correlates with increased levels of HPV16 E6-E7 and E5 transcripts. The HPV16 DNA containing this strong enhancer also transforms C127 mouse cells with increased efficiency and strength relative to the natural HPV16 DNA, as measured by the numbers and size of the colonies in agar. The positive effects of this strong enhancer appear specific for HPVs associated with genital malignancies such as HPV16, since HPV6b DNA (primarily in benign tumors) with or without the strong cytomegalovirus enhancer is incapable of immortalizing primary human cervical epithelial cells or allowing efficient growth of C127 mouse cells in agar. These results suggest that the diminished oncogenic properties of HPV16 versus HPV18 DNA in cultured cells and in human malignancies may reside in the long control regions of these viruses and, additionally, may define another difference in the oncogenic properties of HPVs associated with benign or malignant genital neoplasia.

Animals↗
PubMed1991

Evolution of in vitro transformation and tumorigenesis of HPV16 and HPV18 immortalized primary cervical epithelial cells.

Cervical carcinoma develops through a progressive spectrum of premalignant intraepithelial lesions (CIN I-III), the majority of which are associated with human papillomavirus (HPV) types 16 and 18. We established HPV16 and HPV18 immortalized human cervical epithelial cell lines and used them as a model to investigate the genesis and progression of cervical malignancy. The cell lines when cultured in vitro in a system mimicking their in vivo environment exhibit cytologic atypia and a variety of defects in morphologic differentiation at early passage compared to their normal counterparts. With increased passage, these alterations progress to more severe grades, histologically similar to CIN III; however only a limited number of the cell lines are tumorigenic, mimicking the epidemiologic evidence on the rate of conversion from premalignant to invasive carcinoma. The observed changes are not associated with alterations of viral DNA integration or expression and may reflect specific cellular events or changes in virus-host interactions associated with malignant progression.

Cell Transformation, Neoplastic↗
PubMed1990

Human papillomavirus type 6b DNA required for initiation but not maintenance of transformation of C127 mouse cells.

We describe the transformation of C127 mouse fibroblasts with human papillomavirus type 6b (HPV-6b) DNA, which is associated primarily with benign tumors of the human genital tract. The major transformed phenotype of the HPV-6b-transfected cells lines, which had been G418 selected, pooled, and maintained without subsequent selection, was tumorigenicity in nude mice. We found that, unlike that reported for other HPVs or papovaviruses, the transformed phenotype was expressed after a delay, in which the cells had undergone extensive culture passages (about 20 passages or 100 generations). Interestingly, the HPV-6b DNA had become reduced or nondetectable in copy number in the cells by the time the transformed phenotype was expressed and in most of the tumors induced by the cells in nude mice, indicating that high levels of HPV-6b DNA were not required for maintenance of the transformed phenotype. Clonal cell lines gave similar results. When continued G418 selection was used to maintain high-copy-number HPV-6b DNA, the cells were tumorigenic, indicating that high levels of HPV-6b DNA did not suppress tumorigenesis. These studies suggest that HPV-6b DNA initiates transformation of C127 cells but is dispensable for expression or maintenance of the transformed phenotype. Transformation by HPV-6b DNA in vitro may provide insights into the HPV type-specific association with benign versus malignant lesions in vivo and may elucidate some of the oncogenic processes involved in tumor progression.

Animals↗
PubMed1989

Differential effects of human papillomavirus type 6, 16, and 18 DNAs on immortalization and transformation of human cervical epithelial cells.

The human papillomaviruses (HPVs) are associated with specific benign and malignant lesions of the skin and mucosal epithelia. Cloned viral DNAs from HPV types 6b, 16, and 18 associated with different pathological manifestations of genital neoplasia in vivo were introduced into primary human cervical epithelial cells by electroporation. Cells transfected with HPV16 or HPV18 DNA acquired indefinite lifespans, distinct morphological alterations, and anchorage-independent growth (HPV18), and contain integrated transcriptionally active viral genomes. HPV6b or plasmid electroporated cells senesced at low passage. The alterations in growth and differentiation of the cells appear to reflect the progressive oncogenic processes that result in cervical carcinoma in vivo.

Adult↗
PubMed1988

Transformation of C127 mouse fibroblasts by human papillomavirus 16.

We have compared the ability of cloned DNAs of HPV16, a human papillomavirus associated with cervical carcinoma, and BPV1, a papillomavirus inducing skin lesions in cattle, to transform murine C127 cells. Unlike BPV1, HPV16 DNA failed to induce foci when C127 cells were transfected and maintained as monolayers; HPV16-transformed C127 cells could only be detected after cotransfection with HPV16 and pSV2neo DNA, selection for resistance to G418, and assay of pooled selectants for colony growth in agar. HPV16 and BPV1 C127 cells differed in terms of the size and morphology of their colonies in agar, but not in their colony-forming efficiencies. In addition, the tumors they induced in nude mice were clearly histologically distinct, with the HPV16 C127 tumors considerably more anaplastic. The HPV16 C127 cells contained viral DNA at high copy numbers integrated at random sites in the C127 genome, while the BPV1 C127, as expected, contained episomal BPV1 DNA molecules. The high complexity of the integrated HPV16 DNA was maintained in the pooled cells grown through extended passage in vitro, in clonal lines derived from single agar colonies, in nude mouse tumors induced by the cells, and in a nude mouse tumor-derived cell line, indicating the stability of the HPV16 sequences in the cells. HPV16 transcripts in the transformed C127 cells were present in three size classes (1.5, 2, and 4 kilobases) on Northern blots. The different transformed phenotypes in the same cell line induced by two structurally similar, yet distinct viruses imply differences in the underlying transforming mechanisms and possible different virus-host cell molecular interactions.

Animals↗
PubMed1986

Blood culture and echocardiography in diagnosis of infective endocarditis: microbiological and clinical observations.

Short retrospective review of 77 cases of bacterial endocarditis, observed in the 1980-84 period, and diagnosed by means of echography and blood culture. Alfa haemolytic streptococcus strains were isolated (47.6% of 42 isolated strains) followed by Staphylococcus aureus (16.7%) and Staphylococcus epidermidis (11.9%). Positive bloodculture were more frequent in the patients with valvular prosthesis. The results are analysed and some comments are done.

Adolescent↗
PubMed1985

Diphasic or prolonged course of viral hepatitis A in children.

A study on nine cases of diphasic viral hepatitis A was carried out in 130 children admitted to pediatric hospital from January to December 1982. One hundred and eight children (83.0%) showed IgM anti-HAV (one of them was a chronic HBsAg carrier), 19 (14.6%) were HBsAg positive at the admission and 3 (2.3%) became positive for anti-HBc IgM marker during the course of the illness. Nine anti-HAV IgM positive children showed an atypical course of their disease in that after a short period of progressive enzyme level normalization, a relapse occurred without signs of subsequent HBV, CMV or EBV infection. Probable although hypothetical interpretations of these cases are discussed.

Adolescent↗
PubMed1983

[Epidemiological study on the assay of antibodies to anti-TORCH agents and to HBV in a group of mother/child pairs in Palermo].

The TORCH group: toxoplasma, rubeola, cytomegalovirus (CMV), herpes virus hominis (HSV) and also the B-virus of hepatitis (HBV) determine congenital malformations in the newborns. For this reason, the Authors leaded an epidemiologic study testing with some antibodies (anti-TORCH and anti-HBV) the serum of groups of mother-newborn of the Obstetrical Clinic of Palermo. This study became manageable because now there are available high specific immunoenzymatic methods, for example ELISA, the passive haemoagglutination and the haemoagglutination-inhibition. In our people, high concentration of rubeola, HSV and CMV and very low concentration of toxoplasma and HBV are shown. The frequency of malformation is related with the subclinical infection. The Authors suggest to extend same investigation at an higher number of pregnant women to prevent these congenital malformations.

Adult↗
PubMed1982

Natural cytotoxic cells against solid tumors in mice. IV. Natural cytotoxic (NC) cells are not activated natural killer (NK) cells.

Natural cell-mediated cytotoxicity (NCMC), measured against a variety of tumors, is mediated by at least two sub-populations of effector cells: natural cytotoxic (NC) and natural killer (NK). The studies described in this report show that target lysis by NC cells requires a prolonged (18- to 24 h) assay period, whereas NC-susceptible targets can be lysed in short-term (4h) [3H]-proline assays using allo-sensitized CTL or mitogen-activated cytotoxic populations. NC cells are not "activated" during the long-term assay as indicated by: (1) demonstrating that lysis of NC-susceptible targets in long-term (20 h) 51Cr assays is still the function of a Qa-5- effector cell (NC) and (2) the fact that preincubation of the NC effector cell with susceptible targets for 18 h did not result in the activation of an NK-like population (kinetics of target lysis were comparable to those noted with fresh NC cell preparations). We show that NC cell activity is preserved in both the beige mutant and the PL/J mouse strains, both of which exhibit low NK cell activity, even in long-term assays. These combined studies support the view that NC and NK cell activities are the function of distinct cell types and not the property of a single cell class under different states of activation.

Animals↗
PubMed1982

Ia-dependent interleukin 2 production in syngeneic cellular interactions.

In the murine syngeneic mixed lymphocyte response (SMLR), the co-culture of nylon wool-nonadherent spleen cells or young (4 to 6-day-old) thymocytes with syngeneic nylon wool-adherent adult spleen cells, results in proliferation and Interleukin 2 (IL 2) production. In both the thymus and spleen SMLR, proliferation and IL 2 production are the function of Lyt-1+2-3- (Lyt-1) responder cells and require the expression of IA (IB) and/or IE cell surface antigens on the stimulator cell. IL 2 production in both spleen and thymus SMLR is independent of heterologous serum factors (i.e., fetal calf serum), which, however, influences the magnitude of the in vitro proliferation. The IL 2-producing cell in spleen is capable of self-renewal in the absence of the thymus; it is detectable 6 to 7 mo after adult thymectomy. These results suggest the in vitro SMLR may measure a cellular interaction between the Lyt-1 subset of T cells and self Ia antigens on macrophage-like cells that produces IL 2 in an antigen-independent fashion. This interaction may have physiologic significance in the expression and regulation of T cell function.

Animals↗
PubMed1980

Spermatogenesis before and after renal transplant.

Studies on the relationship of fertility and renal transplantation are relatively recent. Data related to the sexual aspects of uremic patients before and after renal transplantation are available. Information about spermatogenesis, as offered by testicular biopsy, is scarce. The present study has as its objective the quantitative analysis of testicular biopsies obtained pre- and postoperatively from the renal transplant patients after normalization of the renal function.

Adult↗