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V Villanacci

Publications and source records attributed to V Villanacci.

At least 55 records · Page 3Linked to original sources
PubMed2000

Biological and molecular aspects of gastroenteropancreatic neuroendocrine tumors.

Neuroendocrine tumors of the digestive tract are rare entities characterized by significant phenotype differences and traditionally considered to originate from cells of the diffuse endocrine system of the pancreas and gut. Two major categories with significant phenotype and clinical behavior differences are identified as well-differentiated and poorly differentiated tumors. Investigation on the molecular basis of tumor development points to an important role for the multiple endocrine neoplasia syndrome type-1 (MEN1) gene because of its frequent abnormality observed both in well-differentiated and poorly differentiated tumors. Other genes are possibly involved, though the available data need support from studies on larger series of tumors.

Animals↗
PubMed2000

[Gastric metastasis from melanoma. Report of 2 surgically treated cases].

Metastatic disease involving the gastrointestinal tract is a rare pathology and melanoma is the extra-intestinal neoplasm more frequently concerned. Two cases of gastric metastases, revealed by symptoms of upper gastrointestinal bleeding, are reported. In the first case the disease-free interval, after excision of the primary lesion located in the right lower limb, was 13 years; in the second case the primary lesion remained unknown, although it probably originated from a giant congenital nevus of the left foot. Both patients had been affected before by inguinal nodes metastases, treated by radical groin lymphadenectomy; the concomitant multiple metastases to other sites (adrenal glands, retro-peritoneum, liver, lung, small bowel, brain, ovaries) limited surgery to a likely prospect of palliation, conditioning an unfavourable prognosis. Resection of gastrointestinal metastases is justified for the relief of intestinal hemorrhage (as in these reported cases), perforation and obstruction, even if treatment of single non-complicated lesions can have a curative intent. The conclusion is drawn that more aggressive diagnostic and staging procedures are indicated for the early detection of gastrointestinal metastases whenever non-specific abdominal symptoms and a history of melanoma are present.

Aged↗
PubMed1999

Aberrant crypt foci in the human colon: frequency and histologic patterns in patients with colorectal cancer or diverticular disease.

Aberrant crypt foci are considered potential markers of colorectal cancer risk. The aim of this study was to analyze a large series of human aberrant crypt foci according to frequency, distribution, and histology. Aberrant crypt foci were identified in methylene blue-stained colonic mucosa from 103 patients undergoing surgery for colorectal cancer or diverticular disease. Foci were histologically classified into surface hyperplastic type, surface and glandular hyperplastic type, mixed hyperplastic and adenomatous type, and adenomatous type. The mean frequency of aberrant crypt foci (n = 720) was higher in the colorectal cancer group (0.20/cm2) than in the diverticular disease group (0.07/cm2), and in distal colonic segments than in proximal segments. Most of the histologically examined foci (n = 366) were hyperplastic (88.8%). Surface hyperplasia accounted for 30.6% and prevailed in small lesions. Surface and glandular hyperplasia accounted for 58.2% and prevailed in medium-sized to large foci. Partially or totally dysplastic foci accounted for 10.1% of examined lesions (10.8% and 2.8% in the colorectal cancer and diverticular disease groups, respectively). Most of them (94.6%) were composed of mixed hyperplastic and adenomatous crypts and prevailed in large lesions. The higher frequency of aberrant crypt foci in patients with colorectal cancer sustains their putative role as preneoplastic markers. The high rate of mixed hyperplastic and adenomatous lesions supports the possible adenomatous transformation of hyperplastic lesions.

Adenoma↗
PubMed1999

Azoxymethane-induced aberrant crypt foci and colorectal tumors in F344 rats: sequential analysis of growth.

Previous studies are consistent with the hypothesis that aberrant crypt foci (ACF) could be intermediate biomarkers in colorectal carcinogenesis. The present controlled experimental trial was performed to sequentially analyze ACF progression in rat colonic mucosa. F344 rats were administered 2-weekly doses of azoxymethane (15 mg/kg body weight, s.c.) and sacrificed 6, 12, 20, 30 and 36 weeks after the first carcinogen injection. Control groups of untreated rats were sacrificed at the same time points. The number of ACF per area, their multiplicity (number of crypts per focus), ACF frequency and multiplicity according to each colonic site, histology of ACF and macroscopic lesions were recorded. No ACF were found in control animals. In treated animals, the number of ACF per area and the multiplicity progressively and significantly increased throughout the study. ACF were prevalent in the mid colon. Lower frequencies were registered in the distal colon and rectum. ACF were rare in the proximal colon and cecum. By histology, ACF presented superficial and extensive hyperplasia. Tumors were found in the 30th and 36th week. Adenomas and well-differentiated adenocarcinomas were in the distal colon. All proximal neoplasms were signet ring cell carcinomas. In our study, ACF growing features and distribution are not correlated to adenoma and adenocarcinoma distribution. It is conceivable that signet ring cell carcinomas arising in the proximal colon, where ACF are rare, could present a different pathway of growth. The preneoplastic role of ACF and their function as intermediate biomarkers in colorectal carcinogenesis remain to be clarified.

Adenocarcinoma↗
PubMed1999

Inhibitory effect of a gastrin receptor antagonist, CR2945, on 1, 2-dimethylhydrazine-induced colorectal cancer in mice.

This study tested the effect of a new gastrin receptor antagonist, CR2945, on colorectal cancer induced by 1,2-dimethylhydrazine (DMH) in mice. 75 CD1 male mice were divided into 3 groups: group 1 received 1 weekly injection of 20 mg/kg of DMH and 2 daily intraperitoneal injections of 0.5 ml of NaCl 0.9% solution for 5 weeks; groups 2 and 3 received the same weekly dose of DMH and 2 daily injections of CR2945 at the respective doses of 2.5 and 7.5 mg/kg for 5 weeks. The animals were sacrificed 25 and 38 weeks after the first injection. No tumours were found at the 25th week. A lower cancer frequency (4%) was observed in treated animals compared to controls (37.4%) at the 38th week (p = 0.002). These data show that CR2945 could prevent chemically induced colon cancer development in mice.

1,2-Dimethylhydrazine↗
PubMed1999

[Helicobacter heilmannii: anatomo-clinical study of 14 new cases].

INTRODUCTION: Helicobacter pylori is one of the most common causes of human gastritis. Recently, a new agent has been isolated, which also causes a gastritis. It has been initially named Gastrospirillum hominis and renamed Helicobacter heilmannii (Hh). Hh is extremely rare. In spite of the rarity it is important to recognize and diagnose it, as it requires a proper therapy, different from Hp therapy. Clinical presentation and serological results of Hh are superimposable to those of HP. Therefore differential diagnosis resides on histological grounds. PURPOSE of the present paper is to report 14 new cases of Hh gastritis, which constitutes the first italian series. RESULTS: Cases constituted 0.01% of all gastric biopsies seen in the period 1994-1998. Nine patients were male and five were female; age ranged from 32 to 76 years (50 years on average). All patients presented a mild to moderate gastritis. Hh is a spiral bacterium, being about 10 micra in length, localized in single or small groups in the glandular mucus. Two cases were associated with Hp. One case was associated with gastric adenocarcinoma. Two cases were diagnosed during the follow-up of duodenal ulcer. In CONCLUSION, the incidence of Hh gastritis in the present series seems consistent with that from other European countries. In all cases the presence of Hh was associated with features of gastritis. This confirms the pathogenetic role of Hh.

Adenocarcinoma↗
PubMed1999

[Intestinal brushing. Technical-cytological contribution in the pathological study of Vater's ampulla, common bile duct, and pancreatic system].

OBJECTIVE: This experience shows the effectiveness of the cytological examination in the diagnosis of biliary and pancreatic neoplasm on samples obtained from Vater's papilla through endoscopic intestinal brushing. STUDY DESIGN: From June 1997 to October 1998, 28 patients, suffering from suspicious neoplasm of Vater's papilla or biliary system, were studied. Each sample was obtained through intestinal brushing during an Endoscopic Retrograde Colangio-Pancreatography (ERCP) and processed with the technique of direct smear stained with Papanicolaou's method. The sample was followed by the corresponding biopsy in 16 cases and by surgical specimens in 8 cases. RESULTS: 27 patients out of 28 were correctly classified by the intestinal brushing. The method carried out a positive predictive value of 100% and a sensitivity of 93%. The sensitivity of biopsy turned out to be 80%. CONCLUSIONS: The intestinal brushing is an effective method of diagnosis, which turned out to be relevant as a support and, in several cases, as a substitute of the biopsy. We think, therefore, that the brushing should be carried out whenever a lesion of the Vater's papilla or of the biliary system is suspected during an ERCP.

Adult↗
PubMed1998

[Flow cytometry sutdy of DNA and cell kinetics in the adenoma- carcinoma sequence in the large intestine].

UNLABELLED: The quantitation of DNA and growth fraction in the different step from dysplastic to neoplastic process in large bowel is the aim of this study. 70 colonic polyps were studied. The fresh specimens were processed and DNA analysis was carried out using a Partec CA II flow cytometer and the growth fraction was tested with KI-67 monoclonal antibody. The percentage of S-phase cells has been calculated with the Multicycle program. Our results demonstrated that 7 adenomas were tubulo-villous with mild dysplasia, 39 with mild-moderate dysplasia, 1 with severe dysplasia, 5 were polypoid carcinomas, 2 juvenile polyps, 1 polypoid leiomyoma, 1 inflammatory fibroid polyps. DNA analysis showed a diploid DNA content in non adenomatous polyps, in all adenomas with mild dysplasia, in 37 with mild-moderate dysplasia, in 8 cases with moderate-severe dysplasia and 1 cancer. Aneuploidy was discovered in 2 cases with mild-moderate dysplasia, in 6 cases with moderate-severe dysplasia, in the case of severe dysplasia and in 4 cases of carcinomas. Best indexes of linear correlation (Pearson's r) has been found between S-phase and DNA index (r = .75) and between S-phase and KI-67 (r = .82). IN CONCLUSION: 1) No relationship was found between DNA content and age, sex, size and location of polyps. 2) Aneuploidy is strictly related to moderate-severe grade of dysplasia therefore it is an important element in the development of adenomacarcinoma sequence. 3) DNA-index, S-phase and KI-67 are strictly related.

Adenocarcinoma↗
PubMed1998

[Gastric polypoid angioma: a rare cause of bleeding in the elderly. Report of a case and review of the literature].

In 10,700 upper gastrointestinal endoscopies performed between 1990 and 1995; one case of gastric haemangioma was observed. The rarity of this tumour, which represents 0.05% of all the digestive neoplasms is underlined and its features and clinical history are reported. This case and the other four reported in Italy during the last fifteen years are critically reviewed. The various diagnostic-therapeutic pictures emerging from literature are examined.

Aged↗
PubMed1996

Prevalence and diagnosis of celiac disease in IgA-deficient children.

BACKGROUND: Reported frequencies of celiac disease in selective IgA deficiency in childhood vary widely and this is probably due to the different characteristics of the patients studied and to the different criteria used for intestinal biopsy: all patients or only those with symptoms of malabsorption. Diagnosis of celiac disease is of considerable importance in IgA deficiency because of its increased frequency and also because avoidance of dietary gluten permits elimination of the symptoms and complications of celiac disease. OBJECTIVES: To obtain a more reliable estimate of the incidence of celiac disease in childhood IgA deficiency jejunal biopsies were performed in 65 consecutively diagnosed IgA-deficient children whose parents consented. Some clinical and laboratory parameters including IgA-antigliadin and IgG-antigliadin antibodies were evaluated to predict their usefulness in selecting IgA-deficient patients for intestinal biopsy. METHODS: All IgA-deficient patients had serum IgA levels below 5 mg/dL and salivary IgA below 0.5 mg/dL. Jejunal biopsy was performed using a peroral Watson capsule and IgA-antigliadin and IgG-antigliadin antibodies were performed by an ELISA assay. RESULTS: Biopsy findings of severe villous atrophy permitted diagnosis of celiac disease in 7.7% (5/65 children). IgG-antigliadin antibody levels, elevated in 16 patients including all five celiacs, were the best parameter for predicting celiac disease and gave no false negatives. CONCLUSIONS: The 7.7% frequency of celiac disease observed in these IgA-deficient children is about 20 times higher than in the general Italian population, and the lowest among the studies biopsying all patients; this is probably attributable to the presence of a substantial proportion of healthy children (20/65) and very few (2/65) with autoimmune disorders. The elevated sensitivity and negative-predictive value of IgG-antigliadin antibodies lead us to suggest that positive IgG-antigliadin antibodies can be used to select IgA-deficient children for jejunal biopsy with a very low probability of missing celiac disease while allowing a drastic reduction in the number of biopsies performed.

Adolescent↗
PubMed1995

Different neurotransmitter systems are involved in the development of esophageal achalasia.

Clinical and pharmacological evidence suggests that several neurotransmitters are involved in the control of the esophageal motility; in fact, besides the well known cholinergic and sympathetic innervation, Vasoactive Intestinal Polypeptide (VIP)-containing fibers as well as dopamine (DA)-containing nerve endings have been identified within the esophageal wall. Lower Esophageal Sphincter (LES) achalasia is a neuromuscular disorder characterized by the absence of peristalsis in the body of the esophagus and by the failure of the LES to relax in response to swallowing. Stimulation of both VIP receptors and D-2 DA receptors induce a decrease in LES pressure, while D-1 receptors mediates LES contractions. In the present study we show that both VIP and DA system is disregulated in LES achalasia. In particular, this disease is associated not only with the lack of VIP nerves in the LES, but also with a failure in the responsiveness of postsynaptic receptors to VIP stimulation. Furthermore, we demonstrate a selective functional loss of the D-2 DA receptor component, without changes in the D-1 DA receptor mediated responses.

Adenylyl Cyclases↗
PubMed1995

[Cystic adenoid carcinoma of the esophagus. Description of a case and review of the literature].

The clinical and histopathologic characteristics of a case of adenoid cystic carcinoma of the esophagus are reported. The authors reviewed the literature on the matter and stressed the more aggressive behaviour of the tumor that differs from the same tumor of the salivary glands and other anatomical sites. Surgical resection is the treatment of choice, however the aggressiveness of the tumor requires, also, a chemo and radiotherapeutic approach.

Carcinoma, Adenoid Cystic↗
PubMed1993

Expression of cell adhesion molecules in jejunum biopsies of children with coeliac disease.

The composition of inflammatory cells as well as the expression of cell adhesion molecules (LFA-1/CD11a, ICAM-1/CD54, CD36) in jejunal biopsies from children with active, untreated coeliac disease (CD) has been analyzed and compared with control biopsies. In CD the number of intraepithelial and lamina propria T cells was greater than in controls. ICAM-1 was found on most cells in the lamina propria; many of them expressed LFA-1 as well. In contrast, no ICAM-1+ and a few LFA-1+ cells were noticed in the epithelium. The brush border from control biopsies reacted with HLADR and anti-CD36. In CD, de novo expression of HLADR was found in the cytoplasm of villous and cryptal enterocytes in contrast, CD36 disappeared from the brush border and no expression of ICAM-1 on the inflamed epithelium was noticed. The results indicate that adhesion molecules other than LFA-1, ICAM-1 and CD36 may be involved in the cellular interactions occurring in the intraepithelial compartment in CD; the lack of ICAM-1 and the reduced expression of LFA-1 on intraepithelial lymphocytes might reflect a defective activation of these cells. Several macrophages were found in the lamina propria in cases of CD; some of them were located beneath the surface epithelium, showed a spindle/dendritic morphology, and expressed the HLADR+, CD36+, CD11a- phenotype. These cells might be stimulated by luminal antigens and might play an important role in subsequent activation of T cells in the lamina propria.

Adolescent↗
PubMed1991

Helicobacter pylori infection induces antibodies cross-reacting with human gastric mucosa.

The authors' previous observation that many of the monoclonal antibodies against Helicobacter pylori cross-react with the cells of the human gastric mucosa prompted them to investigate the possibility that gastric self-antigens cross-reacting with H. pylori could be involved in the immune response against this organism. It was found that three antibodies against H. pylori, CB-4, CB-10, and CB-14, that cross-react with the human gastric mucosa also intensely cross-reacted with murine gastric epithelial cells. A strong reaction against autologous mucosa was also evident in the sera of mice immunized with H. pylori but not with other bacteria. A serological study performed in a group of 82 patients undergoing gastroscopy showed that the presence of seropositivity against H. pylori was strongly correlated with the presence of autoantibodies against human antral gastric mucosa. This activity was neutralized after absorption of the sera with H. pylori but not with other gram-negative bacteria. The antibodies in the mouse and in the human did not react with other segments of the gastrointestinal tract or with most of the other organs. Mice bearing hybridomas secreting a cross-reacting antibody (CB-4) had histopathologic abnormalities in their stomachs. These lesions were absent in the stomachs of mice bearing hybridomas secreting a non-cross-reacting antibody (CB-26). It was concluded that H. pylori infection can stimulate antibodies cross-reacting with gastric autoantigens and that this immunologic mechanism may represent a pathogenic link between H. pylori and gastritis.

Animals↗
PubMed1990

[Eosinophilic gastritis. Clinico-pathologic considerations on a case and review of the literature].

The clinical, radiographic and histological features of a case of eosinophilic gastritis in a 26 year old-man without personal or familial signs of allergy are reported. The Authors pointed out the importance of radiographic and histological aspects of the case studied. Therefore they represent essential methods for a correct diagnosis and an appropriate management that in this case is only pharmacological. The diagnosis of eosinophilic gastritis is, however, important for the recognition of specific allergens.

Adult↗