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M Napolitano

Publications and source records attributed to M Napolitano.

At least 55 records · Page 3Linked to original sources
PubMed1998

Endothelin-1: expression and role in human corpus luteum.

PROBLEM: Several recent data suggest an involvement of endothelin (ET)-1, a powerful vasoconstrictor peptide, in reproductive function. This study was designed to investigate the presence and role of ET-1 in human corpus luteum. METHOD OF STUDY: Purified luteal cells were incubated for different times with ET-1 or ET-3 alone or associated with human chorionic gonadotropin. In another set of experiments cells were treated with ET-1 and BQ485, an ET-A receptor antagonist, or with phorbol 12-myristate-13 acetate (PMA), an activator of protein kinase C. RESULTS: ET-1 reduced both basal and human chorionic gonadotropin-induced progesterone production at all examined times, similarly PMA inhibited basal progesterone synthesis. BQ485 prevented the inhibitory effect of ET-1, while no effect was observed with ET-3. Finally, ET-1 mRNA was detected in the luteal cells. CONCLUSION: ET-1 is expressed by human luteal cells and reduces basal and human chorionic gonadotropin-induced progesterone synthesis through the ET-A receptors and the protein kinase C pathway. Conversely, ET-3 does not affect luteal steroidogenesis.

Adult↗
PubMed1998

Immunological phenotype analysis of patients with Fanconi's anaemia and their family members.

In contrast to patients affected with Fanconi's anaemia (FA), who are homozygotes, parental heterozygotes are generally considered normal. In this preliminary work the main immunological phenotypes of circulating mononucleated cells were studied, both in homozygous and heterozygous subjects. The statistical analysis of results showed that two sets of variables may be distinguished: (a) the first set, including CD20, CD4, CD8 cell markers and CD20/CD3 and CD4/CD8 ratios, that was able to differentiate between FA patients and the other subject groups; (b) the second set, including CD25, HLA-DR, HLA-DP, HLA-DQ cell markers, that was able to differentiate healthy subjects from the other groups. Therefore, in contrast with the literature data, immunological abnormalities may already be present in parental heterozygotes of FA patients. These subjects displayed a reduced number of cells expressing both specific (CD25) and non-specific (HLA) antigens. This defect was more severe in FA homozygous patients, who showed, in addition, a reduced total lymphocyte count, reduced levels of T helper (CD4+) and B lymphocytes (CD20+), and a reduced CD4+/CD8+ cell ratio. In conclusion, our results suggest the presence of a grading of immunological defects in FA patients and family members. Our suggestion needs to be confirmed by functional studies.

Antigens, CD↗
PubMed1997

Isolation and chromosomal localization of GPR31, a human gene encoding a putative G protein-coupled receptor.

The screening of a human genomic library with a chemokine receptor-like probe allowed us to obtain a putative member of the G protein-coupled receptor gene (GPCR) family, designated GPR31. Its deduced amino acid sequence encodes a polypeptide of 319 amino acids that shares 25-33% homology with members of the chemokine, purino, and somatostatin receptor gene families. Amino acid sequence comparison reveals that the best match in the protein databases is with the human orphan GPCR called HM74 (33% identity). Southern genomic analysis of the GPR31 gene shows a hybridization pattern consistent with that of a single-copy gene. Using fluorescence in situ hybridization, we have determined the chromosomal and regional localization of the GPR31 gene at 6q27. The GPR31 mRNA is expressed at low levels by several human cell lines of different cellular origins. The phylogenetic analysis suggests that the GPR31 receptor may represent a member of a new GPCR subfamily.

Amino Acid Sequence↗
PubMed1997

Cholinergic stimulation of human microcytoma cell line H69.

Experiments were addressed to investigate the mechanisms by which cholinergic stimulation is coupled to the enhancement of proliferation of small cell lung cancer cells H69. Muscarinic stimulation triggers the release of cytosolic Ca2+ and of inositol(1,4,5)trisphosphate with comparable time courses. The presence of alpha-bungarotoxin or the absence of Ca2+ in external medium suppresses enhancement of clonal growth induced by brief applications of nicotine. Here we suggest that Ca2+ mobilization represents a trigger for the enhancement of small cell lung cancer cell proliferation upon cholinergic stimulation.

Acetylcholine↗
PubMed1997

Relation of mood ratings and neurohormonal responses during daily life in employed women.

Diurnal variations in urinary norepinephrine, epinephrine, cortisol, and self-reported mood states were examined in 101 employed women. Urine was collected on 2 consecutive workdays at 3 time periods: (1) overnight, (2) daytime, and (3) evening. Self-reports of 14 mood states were combined to correspond with the urinary collection periods. Factor analyses revealed 3 mood factors: Pressured (rushed, busy, stressed, hassled, and tense), Distressed (afraid, depressed, bored, and nervous), and Contented (satisfied, thoughtful, excited, and calm). The Distressed factor was significantly associated with norepinephrine excretion (p <.001). The Pressured factor was significantly associated with cortisol, epinephrine, and norepinephrine excretion (p <.001) independent of age, ethnicity, marital status, parental status, department within the company and activity level. Secretion of urinary hormones and the Pressured factor followed the same diurnal pattern. Specifically, as women's self-ratings of feeling pressured initially increased and then decreased over the course of the workday, urinary hormones also peaked and then dropped. Once time of day was statistically controlled, however, the mood factors were no longer significantly related to the urinary hormones.

Journal Article↗
PubMed1997

Surgical treatment of anterior callosal tumors.

OBJECTIVE: Thirteen patients with neoplasm of anterior corpus callosum have undergone our observation during the last two years. METHODS: For the diagnosis, all the patients underwent TC, NMR and stereotactic biopsy. In 6 cases with glioblastomas, a radiation treatment was adopted. The other 7 patients underwent total surgical treatment in 5 cases, and partial in 2 cases, as documented by postoperative contrast-enhanced CT scanning. Histologically, there were: 3 glioblastomas, 1 grade III astrocytoma, 1 neuroblastoma (PNET), 2 pilocytic astrocytomas. RESULTS: Neuropsychological tests carried out on the 5 patients still living showed persistent disturbances of verbal memory in all five and disturbances of verbal phonological fluency in 3 cases. No patient presented apraxia, dysgraphia and dyslexia. CONCLUSIONS: Thus, no severe neuropsychological deficits developed after surgical treatment of anterior callosal tumors.

Adolescent↗
PubMed1997

Modulation of cytokine gene expression by thymic lympho-stromal cell to cell interaction: effect of retinoic acid.

We have examined the expression of a panel of cytokines in thymic epithelial cells and CD4-CD8- (DN) thymocytes following cell to cell lymphostromal interaction, in an experimental model which enhances in vitro thymocyte maturation. Since retinoic acid (RA) has been previously shown to be an inhibitor of thymocyte maturation process in this model, we wanted to analyse cytokine expression in DN thymocytes and thymic epithelial cells following the RA-induced impairment of in vitro thymocyte maturation. Cell to cell lymphostromal interaction results in increased IL2 and decreased IL7 expression in thymocytes while the expression of IL1 beta and IL7 increased and decreased, respectively, in thymic epithelial cells. Addition of RA to lympho-stromal cell co-culture results in the enhancement of IL4 and IL7 expression in thymocytes while in thymic epithelial cells IL1 alpha decreased and IL6 and IL7 increased. These data indicate that discrete patterns of cytokine expression are present in thymocyte precursors and in thymic epithelial cells during in vitro T-cell development. They furthermore suggest that specific cytokine modulation might contribute to the RA-induced impairment of thymocyte differentiation.

Animals↗
PubMed1996

Molecular cloning of TER1, a chemokine receptor-like gene expressed by lymphoid tissues.

Several chemokine receptors have been cloned and shown to belong to a superfamily of seven transmembrane, G protein-coupled receptors. We report here the molecular cloning of TER1, a novel human chemokine receptor-like gene. The amino acid sequence deduced from the TER1 cDNA shows 43, 40, 40, and 39% identity to CCR4, CCR5, CCR1, and CCR2B beta chemokine receptors, respectively. By the use of fluorescent in situ hybridization, we have mapped the TER1 gene to chromosome 3p21, clustered with other chemokine receptor genes. By Northern blot analysis, TER1 mRNA is found to be expressed in the thymus, spleen, and at barely detectable levels in peripheral blood lymphocytes. Moreover, TER1 message in abundant in the NK cell line NK3.3 and in the T cell line MOLT-4. The restricted TER1 expression in cells and tissues of the lymphoid lineage suggests that this receptor may play a role in regulating immune functions.

Amino Acid Sequence↗
PubMed1996

Expression of trKB neurotrophin receptor during T cell development. Role of brain derived neurotrophic factor in immature thymocyte survival.

The relationships between the nervous and the immune systems raise the question of whether neurotrophic factors, in addition to the regulation of neural cell ontogeny, may influence lymphocyte development. We report in this work that the pattern of neurotrophin receptor expression depends on the developmental stage of T cells. The presence of nerve growth factor receptor trkA could not be detected in any of the thymocyte subsets, whereas brain-derived neurotrophic factor (BDNF) receptor trkB was expressed in all thymocyte subpopulations. Interestingly, both trkB mRNA and protein expression inversely correlated with the maturation stage and the differentiation potential of thymocytes, being more expressed in CD4-8- immature thymocytes and progressively declining in CD8+ and CD4+ single-positive and CD4+8+ more mature thymocytes. The developmentally regulated expression of trkB is further shown by the inhibition or enhancement of trkB expression induced by signals that either trigger or impair the transition from immature to more differentiated stages of the thymocyte developmental pathway. Signals generated following the interaction of BDNF with trkB receptor resulted in the stimulation of trkB autophosphorylation and in the up-regulation of the expression of the c-fos gene in CD4-8- cells and enhanced thymocyte survival. Finally, BDNF is expressed in thymic stroma and is further up-regulated by signals generated by the thymocyte/stromal cell interaction. These data suggest that BDNF may be a novel survival factor for thymocyte precursors and support the presence of developmentally regulated feedback mechanisms based on autocrine/paracrine neurotrophin/receptor interactions that may be involved in the thymocyte differentiation process.

Animals↗
PubMed1996

Characterization of the cDNA and gene encoding human PDE3B, the cGIP1 isoform of the human cyclic GMP-inhibited cyclic nucleotide phosphodiesterase family.

Two distinct PDE3 [cyclic GMP-inhibited cyclic nucleotide phosphodiesterase (cGI PDE)] isoforms, cGIP1 and cGIP2, have been identified. Here we report cloning of the cDNA and gene encoding human (H)cGIP1 (classified as PDE3B). The cDNA encodes a protein of 1112 amino acids (approximately 123 kDa). Northern blots indicate that its mRNA is expressed in several adipose tissue depots. The human PDE3B gene is composed of 16 exons spanning more than 114 kb and was localized to chromosome 11p15 by in situ hybridization. Exon/intron boundaries were determined, and genetic polymorphism, confirmed by single-strand conformational polymorphism of DNA from 25 healthy subjects, was demonstrated in exon 4 at nucleotide 1389 (A/G). Two polymorphic dinucleotide repeat sequences were identified in introns 5 and 12.

Amino Acid Sequence↗
PubMed1996

Bcl-2/bax mRNA expression ratio as prognostic factor in low-grade urinary bladder cancer.

Apoptotic cell death represents an important mechanism for the precise regulation of cell numbers, and a defence mechanism against tumoral cell. bcl-2 and bax genes are known to be involved in the control of apoptotic pathways; in particular, the ratio between bcl-2 and bax represents a cell rheostat that is able to predict a cell's response toward life or death to an apoptotic stimulus. In the present study we investigated the role of bcl-2 and bax gene expression in a panel of 37 low-grade tumours of the urinary bladder, and correlated the expression of these genes to the prognosis of patients in a follow-up of more than one year. We found that levels of bax expression higher than bcl-2 in bladder tumours well correlates to a better outcome for patients. Early relapses are much more frequently observed in those patients whose tumours express more bcl-2 than bax mRNA. We conclude that the bcl-2/bax expression ratio may be considered as a marker for disease progression in low grade bladder tumours, independently of clinical staging and histological grading.

Adult↗
PubMed1996

Prevalence of human papillomavirus, cytomegalovirus, and Epstein-Barr virus in the cervix of healthy women.

The prevalence of some sexually transmitted viruses, possibly involved in cervical carcinogenesis, was studied in the cervix of women with normal cytology. The presence of human papillomaviruses (HPV) type 16 and 18, cytomegalovirus (CMV) and Epstein-Barr virus (EBV) genomes in cervical cells taken from 143 healthy Italian women was investigated using the polymerase chain reaction (PCR). The study population was divided into four groups with respect to age as follows: group I, 17 to 25 years, n = 48 women; group II, 26 to 35 years, n = 30; group III, 36 to 50 years, n = 32; and group IV, 51 to 70 years, n = 33. In the first age group prevalence rates of HPV 16, CMV and EBV infection of 23%, 21% and 19% were found respectively. The infection rates of HPV 16 and CMV were shown to decrease with age, with prevalences of HPV 16 at 10% in the second group, 6% in the third and 3% in the fourth and of CMV at 13% in the second and third and 6% in the fourth groups. The prevalence of EBV infection did not decrease with increasing age (19% in the first and third groups, 20% in the second and 18% in the fourth). The occurrence of HPV 18 genome was very low (0-3%) and independent of age. In the first age group a higher percentage of double infections (16.6%) was found than in the three other age groups (6% in the second and third and 3% in the fourth). The finding of multiple infections in younger women requires further study in order to clarify the implications of such viral infections in healthy women and their contribution to the development of genital tract malignancies.

Adult↗
PubMed1994

Modulation of fibronectin and thymic stromal cell-dependent thymocyte maturation by retinoic acid.

Retinoic acid (RA) controls the differentiation of a variety of cell types, although its role in influencing T cell development and the mechanisms potentially involved have not been thoroughly investigated. To study the ability of RA to modulate T cell development, we established a thymic stromal cell line (TC-1S) that supports the phenotypic maturation of CD4-8- double negative (DN) or CD3-4-8- triple negative (TN) thymocyte precursors. Cocultures of either DN or TN thymocytes on a monolayer of TC-1S cells resulted in the appearance of thymocytes with a more mature phenotype (CD4+8+ double positive, CD4+ or CD8+ single positive, and CD3(low) cells). Double negative T cell contact with TC-1S cells also increased the production of fibronectin (FN) by the thymic stroma and the expression of the VLA-4 FN receptor on the DN cells. Ab-mediated inhibition of the interaction between FN and its receptors significantly reduced the level of induced T cell maturation. Addition of RA either to TC-1S cells alone or to the coculture with DN cells decreased stromal cell FN expression, antagonized DN cell-induced increase in stromal cell FN production and significantly inhibited in vitro thymocyte maturation. The effects of RA were likely mediated by RA acid receptors alpha and gamma expressed both in DN thymocytes and TC-1S cells. Together these data suggest that FN/VLA-4 interaction may be an important component of stromal cell-dependent thymocyte phenotypic differentiation and that this interaction can be one of the targets for the influence of RA in T cell development.

Animals↗
PubMed1994

A novel p53 mutant in human breast cancer revealed by multiple SSCP analysis.

DNA from tumor tissue and peripheral blood lymphocytes of primary breast cancer patients was screened for the presence of p53 mutations. In DNA from one tumor we found that the histidine codon 193 (CAT) was somatically converted to arginine (CGT). This amino acid residue is highly conserved in many species, thus suggesting that such mutation plays an important role in the loss of wt-p53 function.

Amino Acid Sequence↗
PubMed1994

Acute intracerebral haemorrhage: circadian and circannual patterns of onset.

Hypothesis of the circannual and circadian variation in onset of intracerebral haemorrhage (CH) was verified, by means of single cosinor method and chi-square test for goodness of fit, in 161 consecutive patients (94 men and 67 women) admitted into the Institute of Neurosurgery of Ferrara Hospital, Italy, over 9 years. The majority of CH occurred in the morning between 06.00 AM and 12.00 noon (36.7% of cases, p < 0.001); when considering the specific anatomical sites, typical supratentorial haemorrhages showed a similar pattern (37.4%, p = 0.01). A similar morning behavior was found when considering subgroups by sex (men 36.2%, women 37.3%), age > or = 60 years (42.5%), no presence of hypertension (39.7%), no presence of diabetes mellitus (33.3%) and non-smokers (30.4%). The results by cosinor analysis yielded a circadian rhythmicity both for total sample and, for the men's subgroup, with a morning peak at 11.44 and 11.25, respectively. For women, however, spectral analysis found a significant ultradian cycle, having a period of 12 h (p = 0.01). A circannual periodicity, with a prevalent peak in February, was found for total sample and males subgroups, too. The results of this study confirm that intracerebral haemorrhages present a characteristic circadian and circannual pattern in onset.

Adult↗
PubMed1994

Detection of human papillomavirus type 16 DNA sequences in paraffin-embedded tissues from the female urinary tract.

We investigated the presence of human papillomavirus-related DNA sequences (HPV 6, 11, 16 and 18) in 33 formalin-fixed paraffin-embedded biopsies from the urinary tract of female patients with recurrent and persistent urethritis and cystitis, using the polymerase chain reaction (PCR). The samples for PCR reaction were selected among tissues examined for histological diagnosis on the basis of the presence of microscopic changes consistent with HPV infection. Sequences homologous to HPV 6, 11 and 18 genome were not found, while HPV 16-related DNA sequences were identified in 25/33 lesions with histopathological diagnosis of metaplasia (1 from the urethra, 23 from the trigone and 1 from the bladder). The results suggest that the spread of HPV in the female urinary tract may not be uncommon and point to the need for further research on the possible pathogenic role in recurrent female disturbances.

Cystitis↗
PubMed1994

High frequency of human papillomavirus detection in urinary bladder cancer.

We investigated the presence of human papillomaviruses (HPVs) types 16 and 18 DNA in formalin-fixed, paraffin-embedded tissues from the urinary bladder (46 transitional carcinomas and 10 non-neoplastic normal urinary samples) to find a possible role for HPV types in urinary tract cancerogenesis. The analysis was performed using polymerase chain reaction followed by filter hybridization with oligonucleotide-specific probes. The HPV16 and/or HPV18 genomes were detected in 23 of 46 (50%) bladder carcinomas and in none of 10 (0%) non-neoplastic urinary samples. These results suggest that HPV16 and 18 may carry a risk for the development of malignancy in the urinary tract as it occurs in the anogenital regions.

Carcinoma, Transitional Cell↗