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G Bergamini

Publications and source records attributed to G Bergamini.

At least 19 recordsLinked to original sources
PubMed1999

Expression and characterization of a novel structural protein of human cytomegalovirus, pUL25.

Human cytomegalovirus (HCMV) UL25 has recently been found to encode a new structural protein that is present in both virion and defective viral particles (C. J. Baldick and T. Shenk, J. Virol. 70:6097-6105, 1996). In the present work a polyclonal antibody was raised against a prokaryotic pUL25 fusion protein in order to investigate the biosynthesis and localization of the UL25 product (pUL25) during HCMV replication in human fibroblasts. Furthermore, pUL25 was transiently expressed in its native form and fused to the FLAG epitope, in COS7 and U373MG cells, in order to compare the properties of the isolated protein and that produced during infection. Immunoblotting analysis revealed a group of polypeptides, ranging from 80 to 100 kDa, in both transfected and infected cells; in vivo labeling experiments with infected cells demonstrated they are posttranslationally modified by phosphorylation. The transcriptional analysis of the UL25 open reading frame combined with the study of pUL25 biosynthesis showed true late kinetics for this protein in infected human fibroblasts. By indirect immunofluorescence both recombinant and viral pUL25 were detected exclusively in the cytoplasm of transfected or infected cells. Interestingly, pUL25 was shown to localize in typical condensed structures in the perinuclear region as already observed for other HCMV tegument proteins. Colocalization of ppUL99 in the same vacuoles suggests that these structure are endosomal cisternae, which are proposed to be a preferential site of viral particle envelopment. Our data suggest that pUL25 is most likely a novel tegument protein and possibly plays a key role in the process of envelopment.

Animals↗
PubMed1998

Human cytomegalovirus product UL44 downregulates the transactivation of HIV-1 long terminal repeat.

OBJECTIVE: Human cytomegalovirus (HCMV) is often isolated from HIV-1-infected patients and the two viruses can infect the same cell type giving rise to direct bidirectional interactions. Whereas the long terminal repeat (LTR) transactivation ability of HCMV immediate early gene (IE1/IE2) is well documented, no information is available on the possible role of other HCMV proteins. In this study, the activity of ppUL44, an early DNA-binding protein, on HIV LTR transactivation was investigated. METHODS: HIV LTR transactivation by ppUL44 in presence or absence of HIV-1 Tat and HCMV IE1/IE2 was determined in J-Jhan and U973 cells through transient transfection experiments with a series of different expression vectors. Some experiments were also performed on U373-MG astrocytoma cells permanently transfected with UL44 or with another HCMV gene used as a control (UL55). RESULTS: The basal transactivation activity of the HIV LTR was not influenced by the presence of ppUL44. On the contrary, the transactivation observed in the presence of Tat, IE1/IE2 or both factors in synergy was strongly downregulated by ppUL44 in a dose-dependent manner. Deletion constructs of ppUL44 demonstrated that the region of the molecule responsible for the inhibition of the LTR is located within the last 114 amino acids at the carboxyl-terminal region. CONCLUSIONS: The results obtained indicate that within the last 114 amino acids of ppUL44 there is a domain that has a negative effect on the ability of HIV-1 LTR to be activated by both its autologous transactivator Tat and the heterologous transactivator HCMV IE1/IE2 functioning individually or synergistically.

Astrocytoma↗
PubMed1998

Age-dependent remodeling of rat thymus. Morphological and cytofluorimetric analysis from birth up to one year of age.

Structural and phenotypic modifications of rat thymocytes from birth up to one year of age, i.e. during maturation and at the beginning of the involutive process of the thymus are described. Since the biological significance and the mechanisms of thymic involution are still a matter of debate, this study aims at clarifying the complexity of the compensatory events occurring during this relatively neglected period of time. Thymuses from Sprague-Dawley rats were analyzed morphologically and morphometrically by light and electron microscopy. At the same time, thymocyte subsets, isolated from the same animals, were characterized by flow cytometry according to physical parameters and phenotypic markers. Results indicate that major changes occur during the first month from birth and from six months onward. In particular, already during the first weeks after birth, thymocytes undergo a slight reduction of mitoses associated with an increased number of apoptoses. Moreover, during the same period of time, flow cytometry revealed an expansion of small thymocytes and changes in thymocyte subsets such as increase of CD4+CD8+ and CD5+alpha(beta)TCR- and a decrease of CD4-CD8-, CD4-CD8+ cells. The thymus of adult rats was characterized by time-dependent decrease of both mitoses and apoptoses, progressive physical disconnection among cells, increase of necrotic areas and fibrosis. Around one year of age tissue changes were associated with a dramatic reduction of the population of large thymocytes and the rise of numerous small thymocytes that were unexpectedly negative for all tested markers. By contrast, medium-size thymocytes exhibited a marked decrease of CD4+CD8+ and CD5+alpha(beta)TCR- subsets. In conclusion, our data indicate that thymus undergoes, with time, a complex remodeling and suggest that thymic involution is not only a simple shrinkage of the organ but rather the result of a series of compensatory mechanisms among different cell populations in a setting of progressive involution.

Aging↗
PubMed1998

Development of a new cytomegalovirus (CMV) immunoglobulin M (IgM) immunoblot for detection of CMV-specific IgM.

We developed a new cytomegalovirus (CMV) immunoglobulin M (IgM) immunoblot to detect CMV-specific IgM in human sera. The new test contains four viral proteins (vp150, vp82, vp65, and vp28) purified from viral particles and four recombinant proteins (rp150, rp130, rp52, and rp38) purified from Escherichia coli. These antigens were individually loaded onto nitrocellulose strips, and the strips were then used to detect CMV-specific IgM by using a mu-specific conjugate. The new assay was evaluated in parallel with one or two IgM enzyme-linked immunosorbent assays (ELISAs) to test 592 serum samples from different groups of latently or acutely infected individuals. The sensitivity of the new assay with respect to the consensus of two ELISAs was 100%, the specificity was 98.6%, the positive predictive value was 96.9%, and the negative predictive value was 100%. We also evaluated the new test by testing sera from pregnant women and transplant recipients with a known clinical history. Our results suggest that the new test combines high sensitivity with high specificity, characteristics that are mutually exclusive with the other commercially available tests. Furthermore, a statistically significant correlation was observed between the number of IgM-reactive bands and the elevated risk of transmission from CMV-infected pregnant women to their offspring.

Adult↗
PubMed1998

The major open reading frame of the beta2.7 transcript of human cytomegalovirus: in vitro expression of a protein posttranscriptionally regulated by the 5' region.

beta2.7 is the major early transcript produced during human cytomegalovirus infection. This abundantly expressed RNA is polysome associated, but no protein product has ever been detected. In this study, a stable peptide of 24 kDa was produced in vitro from the major open reading frame (ORF), TRL4. Following transient transfection, the intracellular localization was nucleolar and the expression was posttranscriptionally inhibited by the 5' sequence of the transcript, which harbors two short upstream ORFs.

Animals↗
PubMed1997

Cell behavior and cell-matrix interactions of human palmar aponeurotic cells in vitro.

The present investigation has been performed to better characterize, in vitro, normal aponeurotic cells in comparison with dermal fibroblasts and with cells derived from Dupuytren's affected aponeuroses. Cells were cultured in monolayer and/or into three-dimensional collagen gels. Cell structure, adhesion, and spreading capability on different substrates, as well as integrin expression were investigated by light and electron microscopy and by flow cytometry. Cell-matrix interactions were also analyzed by gel retraction experiments in the presence, or absence, of RGD peptides and anti-integrin antibodies. Normal aponeurotic cells, compared with dermal fibroblasts, exhibited in vitro peculiar structural features, which were substantially maintained in Dupuytren's aponeurotic cells, irrespective of the substrate they were grown on. By contrast, the aponeurotic cell behavior was different in normal and diseased cells, these latter approaching that of dermal fibroblasts. Normal aponeurotic cells, in fact, were characterized by low efficiency in retracting the collagen gel, low alpha 2, alpha 1, and alpha 5 integrin subunit expression and low adhesion properties onto collagen and fibronectin, whereas cells isolated from the aponeuroses of Dupuytren's patients exhibited higher capability of retracting the collagen gel, increased adhesion properties toward collagen and fibronectin, and higher levels of integrin expression. No differences were observed between dermal fibroblasts from Dupuytren's patients or from normal subjects. These in vitro results are consistent with those previously obtained in situ, suggesting that palmar aponeurotic cells have a peculiar phenotype and that changes in cell-matrix interactions occur in Dupuytren's contracture. Moreover, by comparing data obtained from the retracted fibrotic cords and the still clinically unaffected aponeuroses of the same patients, it may be noted that Dupuytren's disease is not only confined to the clinically involved branches, but includes the whole aponeurosis of the affected hand.

Cell Adhesion↗
PubMed1996

Intracellular production of a major cytomegalovirus antigenic protein in the methylotrophic yeast Pichia pastoris.

We have previously shown that single or multiple epitopes of the major human cytomegalovirus (HCMV) antigens, produced as fusion proteins in prokaryotes can be valuable diagnostic material in the serology of HCMV infection. In this work we moved to a eukaryotic system, to produce one of the most immunogenic HCMV antigens, ppUL44 (also called pp52 due to its apparent molecular size on acrylamide gels), as a non-fusion protein, in an attempt to eliminate some non-specific reactivity of human sera with bacterial carrier proteins. We expressed the DNA encoding ppUL44 in a highly efficient expression system based on the methylotrophic yeast, Pichia pastoris. Good levels of intracellular, soluble pp52 were produced. We observed an indistinguishable pattern of the yeast pp52 from the viral native protein in immunoblotting and a good reactivity with human sera.

Antibodies, Viral↗
PubMed1996

Avascular tympanojugular paraganglioma.

The avascular paraganglioma described in this article appears to be the second such tumor reported in the international literature and the first to be reported in the tympanojugular region. Despite a highly suggestive history and clinical appearance, the tumor showed no signs of vascularization on radiologic studies. The pathologic postoperative study confirmed the diagnosis of paraganglioma with extensive stromal fibrosclerosis and without the typical well-vascularized thin fibrous septa. In the authors' opinion, this observation is notable because of the difficulties encountered in the correct diagnostic interpretation of an avascular mass in the tympanojugular region. In such cases, the possibility of a paraganglioma should always be considered.

Angiography↗
PubMed1996

Ultrastructural and morphometrical evaluations on normal human dermal connective tissue--the influence of age, sex and body region.

In order to give detailed structural and quantitative evaluations for some of the most important dermal constituents such as collagen, elastic fibres and mesenchymal cells, and for the non-structured extracellular matrix, we performed ultrastructural investigations on dermal biopsies from 50 healthy caucasian subjects aged from 6 fetal months to 83 years. Striking changes were observed, mainly in the perinatal period, for collagen, elastin and mesenchymal cells and, after 50 years of age, for collagen and elastin. Only slight or negligible differences were noted between males and females and in skin specimens taken from different parts of the body but similarly exposed to environmental factors (i.e. UV radiation). Modifications of the non-structured extracellular matrix appeared to be the consequence of changes affecting the other components. The results, therefore, emphasize the importance of the ageing factor in connective tissue metabolism and give further information on both qualitative and quantitative characteristics of normal human dermis.

Adolescent↗
PubMed1996

Connective tissue in skin biopsies from patients suffering systemic sclerosis.

Little information is available on elastin during systemic sclerosis since biochemical and morphological data have primarily focused on collagen and glycosaminoglycan alterations of connective tissues in this pathological process. We performed ultrastructural, morphometric, biochemical and in situ hybridisation analyses on skin biopsies from patients affected by scleroderma and from site and age-matched control subjects. Affected skin revealed alterations in the distribution and organisation of collagen bundles and fibrils together with zonal increase of the microfibrillar component. Elastic fibres were significantly more numerous than in control skin, were more frequently vacuolated and characterised by electron-dense inclusions; moreover, morphometric analysis provided evidence for a significant increase of the percentage of both collagen bundles and elastin fibres in the measured tissue, compared to normal skin. Biochemical analysis seemed to confirm the increased elastin content per unit of dried weight tissue in sclerodermic skin. Differences observed among patients were only partially associated with disease duration and/or to severity of clinical manifestations. The abnormal amount of elastic fibres observed in skin biopsies from patients, and data from in situ hybridisation suggest the presence of a deregulation of the whole extracellular matrix that might be related to the role of cytokines such as TGF-beta, which has already been suggested to be involved in systemic sclerosis and in enhanced collagen and elastin production.

Adult↗
PubMed1996

[Reconstructive subtotal laryngectomy in the treatment of laryngeal cancer].

Surgical techniques of sub-total reconstructive laryngectomies can often prevent the serious impairment of total laryngectomy without having to relinquish oncological radicality. The aim of the present work has been to report on the experience in this field accrued in the ENT Department of the University of Modena from 1987 to 1992. During this period 54 subtotal laryngectomies were performed. Of these, 13 were crico-hyoido-epiglotto-pexies (C.H.E.P.) and the remaining 41 were crico-hyoido-pexies (C.H.P.). The criteria suggested in the literature was adopted for tumor evaluation, surgical indications and contraindications. All the patients had a follow-up of at least 2 years and 31 of them have had at least 5 years of follow-up. There were 9 deaths: 3 due to intervening illnesses, 2 from second primary tumors and 4 from tumor and/or node recurrences. The overall survival was 83.3% at 2 years and 77.6% at 5 years. Determinate survival (ruling out those who had died because of intervening illnesses) were 88.2% and 80%, respectively. There were 11 neoplastic repetitions of which 2 were of the primary tumor, 2 of the primary tumor plus cervical metastases, and 7 of cervical metastases alone. Recovery surgery was performed in 9 patients, 5 of whom are still alive and disease free. Functional recovery (respiration, deglutition) took place slightly earlier in C.H.E.P. than in C.H.P. but in both cases this could be shortened, particularly by introducing a rehabilitative protocol during the immediate post-operative period. In no case did it prove necessary to perform a total laryngectomy to avoid "ab ingestis" problems and only one patient has a permanent tracheostomy.

Follow-Up Studies↗
PubMed1995

Construction of a polyepitope fusion antigen of human cytomegalovirus ppUL32 and detection of specific antibodies by ELISA.

We have previously shown that single linear epitopes of the major human cytomegalovirus (HCMV) antigens, expressed as fusion proteins or synthesized as oligopeptides can be valuable diagnostic material in the serology of HCMV infection (5, 6, 13). In this work we fused sequences expressing two different epitopes (aa 1005-1048 and aa 595-614) contained in the basic phosphoprotein of 150 KD coded by UL32 (1, 2), (ppUL32), which has repeatedly been shown to be the strongest immunogen present in the viral particle. The fusion protein was tested by ELISA with HCMV-positive human sera in comparison with other fusion proteins of ppUL32. We found that the double epitope fusion protein was recognised by IgM present in a larger number of sera and with more intense reactions than all the other ppUL32 fusion proteins. The double epitope reacted positively with 81.3% and, when denatured, with 94.7% of IgM-positive sera respectively. IgG reactivity was also high, reaching a percentage of 90.7.

Antibodies, Viral↗
PubMed1995

[Logopedic rehabilitation of laryngeal granulomas].

Posterior laryngeal granuloma is an infrequent pathology of multidisciplinary interest. Actually, its real prevalence is difficult to quantify because in some cases it is asymptomatic and in other instances it may either be reabsorbed or eliminated spontaneously. It is located at the vocal apophysis of the arytenoid or, less frequently, above it or on the laryngeal side of the arytenoid. The many etiologic factors (laryngeal intubation, gastro-esophageal refluxes, blunt trauma of the larynx, vocal dysfunction), sometimes concomitant and with the possible addition of enhancing circumstances (upper aerodigestive tract inflammation, naso-gastric tube, smoking and alcohol abuse), converge to a single pathogenetic mechanism: an ulceration of the mucosa and the pericondrium, sometimes complicated by an infection, which does not heal but instead produces a typical granulation tissue with capillaries oriented radially from the center of the lesion. Post intubation granulomas, extremely rare in children, are more frequent in females. It appears that there is no correlation with duration of intubation in that granulomas, can also occur after short general anesthesia. Idiopathic or contact granulomas are more frequent in the males. They are the result of vocal laryngeal hyperfunction, habitual throat clearing or cough-like throat clearing. Gastro-esophageal reflux of gastric juice, coughing or throat clearing may injure the mucosa. A blunt trauma of the larynx may cause a granuloma if the cartilage of the vocal process is exposed. Symptoms, when present, are dysphonia, tiredness during or after voicing, bolus, laryngeal unilateral pain, sensation of something in the throat which is mobile during breathing and swallowing, traces of blood in the expectoration. Therapeutic options are surgical, medical or logopedic. Surgery, although followed by frequent recurrences, is mandatory when the granuloma causes dispnea or if a pathologic essay is needed. Medical treatment aims at solving gastroesophageal reflux and/or inflammations of the district. Logopedic rehabilitation is the most successful therapy. Since January 1992 the Authors have been adopting the rehabilitation protocol planned by the French phoniatrician Brigitte Arnoux-Sindt for post-intubation granulomas, which, moreover, is utilyzed for all type of granulomas, including those arising during the early postoperative period after cordectomy. This protocol is analytically presented and discussed. In the cases of contact granulomas, and when there is concomitant vocal dysfunction, logopedic treatment is prolonged after granuloma dissapearance with some sessions aiming at restoring correct vocal behaviour. In all the ten patients rehabilitated up to now, granulomas disappeared after a mean of 16.3 sessions held twice a week. After several months of follow-up we had no recurrences. This clinical experience, while limited in number, seems to confirm the good results already reported in French Literature.

Adolescent↗
PubMed1994

Construction of polyepitope fusion antigens of human cytomegalovirus ppUL32: reactivity with human antibodies.

We have previously shown that single linear epitopes of the major human cytomegalovirus (HCMV) antigens, expressed as fusion proteins or synthesized as oligopeptides, can be valuable diagnostic material in the serology of HCMV infection (M. P. Landini, M. X. Guan, G. Jahn, W. Lindenmaier, M. Mach, A. Ripalti, A. Necker, T. Lazzarotto, and B. Plachter, J. Clin. Microbiol. 28:1375-1379, 1990; M. P. Landini, T. Lazzarotto, A. Ripalti, M. X. Guan, and M. La Placa, J. Clin. Microbiol. 27:2324-2327, 1989; A. Ripalti, M. P. Landini, E. S. Mocarski, and M. La Placa, J. Gen. Virol. 70:1247-1251, 1989). In this work we addressed the question of whether the expression of more than one linear epitope on a single fusion protein could increase the reactivity of genetically engineered antigenic material with human antibody. To answer this question we fused sequences expressing two different epitopes contained in the basic phosphoprotein of 150 kDa encoded by UL32 (M. S. Chee, A. T. Bankier, S. Beck, R. Bohni, C. M. Brown, T. Cerny, T. Hornsel, C. A. Hutchinson, T. Kouzarides, J. A. Martignetti, and B. G. Barrell, Curr. Top. Microbiol. Immunol. 154:125-169, 1990; G. Jahn, T. Kouzarides, M. Mach, B.-C. Scholl, B. Plachter, B. Traupe, E. Preddie, S. C. Satchwell, B. Fleckenstein, and B. G. Barrell, J. Virol. 61:1358-1367, 1987), ppUL32, which was repeatedly shown to be the strongest immunogen present in the viral particle. We also made fusions with sequences expressing a single epitope repeated once, twice, or three times. The different fusion proteins were tested with HCMV-positive human sera. We found that fusion proteins expressing different epitopes together were recognized by a larger number of serum specimens and with more intense reactions in Western blot (immunoblot) experiments. We also found evidence that expression on the same polypeptide of the two distinct epitopes produced a stronger antigen than the mere addition of two fusion proteins which each carried one copy of one of these epitopes. Furthermore, we found that while the same epitope expressed two or three times on the same fusion protein was not better recognized by immunoglobulin G than the single epitope, immunoglobulin M reactivities to the double and triple epitopes were enhanced.

Antibodies, Viral↗
PubMed1994

Integrin expression in middle ear cholesteatoma.

Cholesteatoma is lined by a squamous keratinizing epithelium exhibiting most of the features of normal epidermis. In this study, we investigated by immunohistochemistry the expression of integrin adhesion molecules in primary acquired and recurrent cholesteatomas, and compared it with common epidermal cysts and normal human skin. The results showed that cholesteatoma epithelium exhibited a markedly augmented expression of alpha v integrin subunit and a corresponding increased deposition of vitronectin (alpha v ligand) in the surrounding stroma as compared to epidermal cyst and normal human skin. In contrast, the expression pattern of alpha 2 beta 1, alpha 3 beta 1, and alpha 6 beta 4 integrins as well as the distribution of laminin, collagen IV and fibronectin were similar in cholesteatomas, epidermal cysts and normal human skin. Similar staining pattern was observed in primary acquired and recurrent cholesteatoma.

Antigens, CD↗
PubMed1993

Efficacy and tolerability of brodimoprim in bacterial otitis media in children. Controlled study versus cefaclor.

78 pediatric patients affected by acute otitis media were selected and randomized into two balanced groups of treatment: brodimoprim, at the dosage of 200 mg once-a-day on the first day and of 100 mg once-a-day on the following days, and cefaclor at a dosage of 40 mg/Kg/day in three doses. Brodimoprim resulted more efficacious in the reduction of symptoms, especially hypoacusis and tinnitus (p < 0.05 between treatments); tympanometry showed a higher number of normalizations in the brodimoprim group, without significant differences between treatments. Both drugs resulted active against most of isolated bacterial strains. Side effects were reported in 4 patients treated with brodimoprim and in 6 patients in the control group.

Acute Disease↗
PubMed1988

Nasal cytology in allergic processes and other syndromes caused by hyperreactivity.

The spontaneous nasal secretions from about 128 patients with the symptomatic triad of rhinorrhea, sneezing, and nasal obstruction were studied. The cytological examination consisted of a morphological evaluation and a semiquantitative evaluation. Noncellular and nonliving presences in the smears have been considered, including mucus, Charcot-Layden crystals, and pollen grains, as well as fungi and bacilli. We found a net increase in eosinophils, goblet cells, and cellular debris in secretions of atopic patients. Pollen grains and vegetative fragments were present in the nasal smears of pollinosis. The presence of fungi was observed in five cases of allergic rhinopathy. The exfoliative cytology represents a valuable means for the differential diagnosis of rhinitis. In particular, the presence of noncellular elements has value regarding rhinocytology.

Adolescent↗