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Biomedical subjects

A Amorosi

Publications and source records attributed to A Amorosi.

At least 55 records · Page 3Linked to original sources
PubMed1996

Flow cytometric measurement of DNA content in human solid tumors: a comparison with cytogenetics.

The aims of this study were: (1) to test the accuracy of flow cytometery (FC) in the measurement of DNA content in human solid tumors, (2) to correlate the FC DNA-index (DI) with the chromosome modal number (CMN) provided by cytogenetic analysis (CG), and (3) to investigate the most frequent pitfalls in FC histograms classification. FC and CG analyses were performed in parallel on 113 samples of human solid tumors of different origin. FC provided an evaluable histogram in 110 out of 113 cases (97%), whereas a successful CG culture was obtained in 79 out of 113 samples (72%). In the 79 cases evaluable by both FC and CG, a concordant ploidy status was found in 66 cases (84%) (47 diploid and 19 aneuploid) (P < 0.001, chi-square test). In the 19 concordant aneuploid tumors a close correlation between the CMN and the DI was found (y = 0.019 x + 0.151; r = 0.860). Concerning the 13 discordant cases, 11 (85%) were classified as aneuploid by FC and as diploid by CG, while 2 cases (15%) were CG aneuploid (1 near-diploid and 1 tetraploid) and FC diploid. The current study suggests that FC is a reliable method for the measurement of tumor DNA content of the studied solid tumors. Special attention should be paid to the improvement of DNA histograms quality, in order to reduce the difficulties in the detection of near-diploid and near-tetraploid cell populations. Multiple sampling should be warranted whenever possible.

Aneuploidy↗
PubMed1996

Local staging of prostate carcinoma with endorectal coil MRI: correlation with whole-mount radical prostatectomy specimens.

The purpose of this study was to investigate the accuracy of endorectal coil MRI in the local staging of prostate carcinoma. A total of 73 patients with biopsy-proven prostate carcinoma were examined at 0.5 T prior being submitted to radical prostatectomy. The gold standard was provided in all patients by findings at whole-mount sectioning of the surgical specimens. At pathology 28 patients had stage T2, 30 had stage T3a/b, and 15 had stage T3c lesions. Overall accuracy of endorectal coil MRI in defining local tumor stage was 82% (60 of 73 patients). Of 73 patients, 5 (7%) were underestimated and 8 (11%) overestimated. The sensitivity and the specificity of endorectal coil MRI in diagnosing capsular penetration were 95% and 82%, respectively. Seminal vesicle invasion was detected with 80% sensitivity and 93% specificity. Our data indicate that endorectal coil MRI is an accurate method for local staging of prostate cancer.

Humans↗
PubMed1996

Isolated guinea pig gastric chief cells express tumour necrosis factor receptors coupled with the sphingomyelin pathway.

The tumour necrosis factor alpha (TNF), has been implicated in the pathogenesis of non-steroidal anti-inflammatory drug (NSAID) induced gastropathy and Helicobacter pylori induced gastritis. Both conditions are characterised by high plasma pepsinogen concentrations, which are thought to reflect an increased rate of enzyme release by the pepsinogen secreting (chief) cells. The mechanisms responsible for this cell dysfunction are unknown. This study investigates whether chief cells express TNF receptors and, if so, whether their activation results in cell death. Immunohistochemical studies conducted with monoclonal antibodies (mAbs) directed against two TNF receptor associated proteins of 55 kDa (TNF-R1) and 75 kDa (TNF-R2) showed that TNF binding sites were expressed in approximately 100% gastric chief cells. Western blot analysis of whole chief cell lysates probed with the TNF-R1 and TNF-R2 mAbs gave two distinct bands of 55 and 75 kDa in the immunoprecipitate. Incubating chief cells with TNF caused concentration and time dependent cell death, which was prevented by pretreating the cells with anti-TNF receptor mAbs. Exposing the cells to TNF reduced sphingomyelin content by 25%. Sphingomyelinase (10(-6) to 10(-2) IU/ml) mimicked the effect of TNF in that it provoked a concentration and time dependent reduction in chief cell viability and increased pepsinogen release. In conclusion, gastric chief cells express two TNF receptors partially linked to the sphingomyelin pathway. TNF induced chief cell dysfunction might be responsible for the high plasma pepsinogen concentrations seen in patients with NSAID gastropathy or H pylori induced gastritis.

Animals↗
PubMed1996

Paraganglioma of the urinary bladder.

A paraganglioma of the urinary bladder in a 60-year-old woman presented with irritative voiding symptoms, without hematuria or hypertension. Sonography revealed a well-limited ovoid mass of the posterior wall, and cystoscopy showed that it was covered by normally appearing mucosa. Treatment consisted of transurethral resection, and the patient has been followed for 2 years without recurrence. Histologically the lesion consisted of small nests of spindle cells with clear to acidophilic cytoplasm; mitotic activity was inconspicuous. Immunohistochemical analyses revealed that the tumor cells were strongly positive for neuron-specific enolase and chromogranin A, and negative for cytokeratin, vimentin, neurofilaments, glial fibrillary acid protein and HMB 45. Sustentacular cells at the periphery of neoplastic cell clusters were positive for S-100 protein.

Biomarkers, Tumor↗
PubMed1996

Cytofluorometric evaluation of nuclear DNA content distribution in renal neoplasms treated by conservative surgery.

The prognostic value of nuclear DNA content in 21 patients who underwent conservative surgery for renal tumors was the object of a retrospective study. Cytofluorometric evaluation of nuclear DNA content distribution was performed on smears obtained from 50-micron thick histologic sections prepared with the Hedley technique, using a Leitz MPVII microspectrophotometer. The DNA indexes were plotted in the form of frequency histograms. DNA measurements were repeated by a cell image analysis system (CAS 200; Becton Dickinson) in 16/21 cases. Nuclear DNA content was diploid in 12 cases, triploid in 4, tetraploid in 2 and multiclonal in 3. No statistically significant correlation was found between ploidy and tumor stage and size, using Kendall's tau test, while there was a significant correlation between tumor ploidy and nuclear grade (p < 0.01). Excluding 2 postoperative deaths, with an average follow-up of 54 months, tumor diffusion was observed in 2 patients (1 with multiclonal and 1 with triploid DNA content) and a local recurrence in a patient with a triploid tumor. Of the remaining 16 no evidence of disease (NED) cases, 10 have a diploid DNA tumor content, 2 diploid, 2 tetraploid and 2 multiclonal. It is concluded that even after conservative surgery for renal neoplasms a diploid DNA content is a favorable prognostic factor. A completely negative prognostic impact of nondiploid tumors is not confirmed, since although all three negative events occurred in this group, there are also 4 NED patients with respectively 70, 46, 43 and 40 months' follow-up.

Adult↗
PubMed1996

A population-based study of inflammatory bowel disease in Florence over 15 years (1978-92).

BACKGROUND: In the group of inflammatory bowel disease (IBD), ulcerative colitis (UC) and Crohn's disease (CD) are considered to be more frequent in Western countries and in areas with a high socioeconomic development but relatively infrequent in southern Europe. Sporadic reports have indicated a lower incidence and a milder course of the disease in Mediterranean countries. Although conclusive data on this point are still lacking, recent reports suggest an increase in both incidence and prevalence rates. METHODS: The incidence of UC and CD during the period January 1978 to December 1992 and their prevalence on 31 December 1992 were estimated in the 15-year-old population of the metropolitan area of Florence. Clinical, demographic, and follow-up information was collected for all identified IBD patients. RESULTS: A total of 796 residents (345 females and 454 males) were newly diagnosed as having IBD during the study period. Of these 593 had UC and 203 CD. The age-standardized incidence rates, calculated for each of five 3-year consecutive periods, rose from 3.8 (in 1978-80) to 9.6 per 100,000 person-years (in 1990-92) for UC and from 1.9 (in 1978-80) to 3.4 (in 1990-92) for CD. Both trends were statistically significant. The prevalence estimated on 31 December 1992 was 121.0 and 40.0 per 100,000 inhabitants for UC and CD, respectively. CONCLUSIONS: Our results confirm that IBD incidence rates and prevalence in this area of central Italy are currently comparable with those reported in northern Europe. These data are necessary for planning adequate health care services for IBD patients.

Adolescent↗
PubMed1996

Helicobacter pylori and cell proliferation of the gastric mucosa: possible implications for gastric carcinogenesis.

OBJECTIVES: Helicobacter pylori infection is recognized as a risk factor for gastric adenocarcinoma. "Mitogenesis increases mutagenesis," so the effects of H. pylori infection on the gastric mucosal proliferative compartment have been investigated. METHODS: In 25 H. pylori-positive and 19 H. pylori-negative subjects, epithelial cell proliferative activity and the pattern of the proliferative compartment were separately evaluated in relation to both the different type of mucosa (antrum and corpus) and the H. pylori positivity/negativity after 3H-thymidine labeling. RESULTS: Both mucosal cell kinetics and the pattern of the proliferative compartment in the antrum appeared different from those of the corpus. Comparing H. pylori-positive and H. pylori-negative subjects, differences were detected only in the total number of cells in the antrum, whereas all of the cell kinetics parameters, except the labeling index, were greater in the corpus of the former group. A superficialization of the proliferative compartment was shown in H. pylori-positive subjects. Changes were more evident in subjects with more severe gastritis but were also present in H. pylori-positive subjects without corpus gastritis. CONCLUSIONS: These results show that H. pylori infection is associated with modifications in the proliferative compartment of the gastric mucosa. Both infection per se and chronic gastritis seem to be relevant for such changes.

Adult↗
PubMed1996

Helicobacter pylori and duodenal ulcer: evidence for a histamine pathways-involving link.

OBJECTIVES: A "gastrin link" has been suggested to explain the statistically relevant association between Helicobacter pylori and duodenal ulcer. Given the well known, although not entirely clarified, relationships between gastrin and histamine, the purpose of this study was to assess whether gastric mucosal histamine pathways and, more specifically, histamine-storing cells are involved in the Helicobacter pylori-duodenal ulcer route. METHODS: Fasting serum gastrin, gastric mucosal histamine content, and mucosal density of both enterochromaffin-like cells and mast cells were compared in 11 H. pylori-positive, non-duodenal ulcer subjects, in 16 duodenal ulcer patients (all H. pylori positive), and in 11 H. pylori-negative control subjects. RESULTS: Fasting serum gastrin concentration and mucosal histamine content were significantly higher in the duodenal ulcer group than in controls, whereas H. pylori-positive, non-ulcer subjects had values that were intermediate between those of the other two groups. Enterochromaffin-like cell density was significantly greater in duodenal ulcer patients than in the other groups. CONCLUSIONS: These results demonstrate the involvement of histamine pathways in H. pylori infection and duodenal ulcer. The most original finding in this study was that enterochromaffin-like cell density is three times greater in duodenal ulcer patients than in H. pylori-positive, non-ulcer subjects. This could explain the previous report of an exaggerated acid response to gastrin in duodenal ulcer patients when compared with H. pylori-positive, non-ulcer subjects and thus provide further insight into the pathogenesis of ulcers.

Biopsy↗
PubMed1995

Mutations of the K-ras and p53 genes in gastric adenocarcinomas from a high-incidence region around Florence, Italy.

K-ras and p53 gene mutations in intestinal-type gastric carcinomas from a high-incidence area around Florence, Italy, were studied by single strand conformation polymorphism and DNA sequencing analysis. Single-strand conformation polymorphism analysis of K-ras indicated aberrant bands in 13 of 34 cases. Sequencing revealed point mutations in 7 (including two at a previously unreported site in codon 11), a significantly higher frequency than reported in countries other than Japan. No K-ras mutations were identified in stage III tumors. Single-strand conformation polymorphisms in p53 exons 5-8 occurred in 30 of 34 cases, with mutations identifiable by direct sequencing in 65% of the cases. Of these, 91% were base substitutions, a value similar to that usually reported, but the percentage of G:C to A:T transitions (90% in this study, 89% in all published European cases combined) differed significantly from that in Oriental cases (48%). The percentage of A:T to G:C transitions was greater in Oriental (22%) than European cases (2%), as was also true for transversions (30% in Oriental tumors, 9% in European tumors). The frequency of mutations at CpG sites (14%) varied significantly from the 67% in cases from a neighboring region in Italy. Helicobacter pylori infection was established in 19 cases and was somewhat more common in cases lacking a p53 mutation.

Adenocarcinoma↗
PubMed1995

Effects of short chain fatty acids on mucosal proliferation and inflammation of ileal pouches in patients with ulcerative colitis and familial polyposis.

PURPOSE: To verify whether short chain fatty acids (SCFA) alter the proliferative and endoscopic pattern of the mucosa in ileal pouches of ulcerative colitis (UC) or familial adenomatous polyposis (FAP) patients. METHODS: We studied patients after proctocolectomy carrying a pelvic ileal pouch for FAP or UC (noncanalized pouches in 10 UC and 4 FAP patients and canalized pouches in 6 UC and 5 FAP patients). Patients with noncanalized pouches were treated twice daily for one week with 30 ml of a SCFA solution (60 mM sodium acetate, 30 mM sodium propionate, 40 mM sodium butyrate, and 22 mM sodium chloride, pH 7); patients with canalized pouches were treated with the same solution twice daily for two weeks. Pouch mucosal biopsies were collected before and after SCFA. Mucosal proliferation was assessed by incorporation of [3H]thymidine in vitro and autoradiography. RESULTS: In UC patients proliferation did not vary in noncanalized pouches but was significantly reduced in canalized pouches after SCFA. In FAP patients SCFA did not alter proliferation. No significant effects of SCFA were observed on daily defecation frequency, endoscopic appearance, or histopathology of the pouches. CONCLUSIONS: SCFA do not control inflammation and clinical functions but reduce cell proliferation in UC patients. On the contrary, FAP patients are refractory to SCFA.

Adenomatous Polyposis Coli↗
PubMed1995

Gastric mucosal histamine storing cells. Evidence for different roles of mast cells and enterochromaffin-like cells in humans.

Gastric mucosal histamine content, enterochromaffin-like cell density, and mast cell density were studied in 13 subjects under omeprazole therapy, 13 partially gastrectomized subjects with a Billroth II reconstruction, 10 partially gastrectomized subjects with a Roux-en-Y reconstruction, and 9 control subjects. Histamine content was significantly greater both in the subjects with higher gastrinemic levels (omeprazole-treated subjects) and those with more abundant enterogastric reflux (Billroth II subjects) than in controls. Enterochromaffin-like cell density was significantly greater in the omeprazole subjects than in each of the other groups. Mast cell density was significantly greater in Billroth II subjects than in controls. Serum gastrin levels, mucosal histamine content, and enterochromaffin-like cell density were positively correlated. Gastrin was not correlated to mast cell density. These results support the existence of different control pathways for enterochromaffin-like and mast cells. Moreover, they suggest that enterochromaffin-like cells and mast cells are involved in the regulation of gastric secretion and in gastric mucosal injury-repair mechanisms, respectively, due to histamine release.

Aged↗
PubMed1995

Bacteriologic, histologic and ultrasonographic findings in strictures recurring after urethrotomy. A preliminary study.

Twelve men with recurrent anterior urethral stricture after endoscopic urethrotomy (2-12 attempts) underwent open urethroplasty with en bloc removal of diseased urethral segments. Bacteriologic and histologic studies of the excised urethral tracts (mucosa and spongiosum tissue) were performed. The bacteriologic findings were compared with the results of preoperative urine cultures and urethral swabs for chlamydia. The histologic findings were related to preoperative ultrasonographic observations, in order to evaluate the accuracy of ultrasonography in depicting structural changes in spongiosum around the strictured urethral tract. Beta-haemolytic streptococci and Streptococcus faecalis were cultured from the excised spongiosum, without correlation to the preoperative culture results. The histologic studies confirmed the usefulness of urethral ultrasonography for accurate demonstration of the inflammatory changes involving spongiosum around the strictures.

Adult↗
PubMed1994

Asynchronous bilateral non-Hodgkin's lymphoma of the testis: report of three cases.

Asynchronous involvement of both testes by non-Hodgkin's lymphoma was observed in 3 patients ranging in age from 38 to 82 years. According to the Working Formulation, all cases were classified as large cell immunoblastic lymphomas, and immunohistochemical studies demonstrated a T-cell phenotype in 1 patient and a B-cell phenotype in 2 patients. Relapse to the contralateral testis occurred after a mean interval of 6 months. The negative prognostic impact of these neoplasms is confirmed in the present series, since 2 patients died of disease 7 and 9 months after diagnosis and 1 patient had a laterocervical and Waldeyer's ring recurrence after 1 year.

Adult↗
PubMed1994

Intermittent versus continuous 5-aminosalicylic acid treatment for maintaining remission in ulcerative colitis.

We performed a 12-month clinical trial to compare the relative effectiveness of an intermittent 5-ASA regimen and a continuous 5-ASA regimen for the maintenance treatment of patients with ulcerative colitis in remission. Fifty patients with ulcerative colitis in remission for a minimum period of 1 month participated in the study. Twenty five patients received an intermittent treatment with 5-ASA tablets (2.4 g for the first week of each month) and 25 received a continuous treatment with tablets (1.6 g each day). Patients were assessed clinically every two months and endoscopically every 6 months. Our results show that the two treatments were equally effective. The relapse-free rates at 12 months were 71% in patients receiving the intermittent treatment and 66% in patients given the continuous treatment. This difference is not statically significant. Further studies are needed to assess whether the intermittent regimen can be an alternative to life-long treatment in patients who have maintained remission for a long period of time.

Administration, Oral↗
PubMed1994

[Thyroid cancer: anatomy and pathologic histology].

Current pathological classifications of thyroid carcinoma only partially reflect the radical changes in our knowledge of these tumors, due to a large series of clinicopathological studies carried out over the past few years. Based on a critical review of this growing body of information concerning malignant thyroid neoplasms, a working formulation for clinical usage is proposed. This scheme has been adopted to classify 1339 consecutive cases of thyroid carcinoma observed at the Pathology Institute of the University of Florence between June 1966 and December 1993. The clinical implications of newer classification systems with regard to diagnosis, treatment and outcome of thyroid carcinoma are also discussed.

Adenocarcinoma↗