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A Parenti

Publications and source records attributed to A Parenti.

At least 19 recordsLinked to original sources
PubMed2006

Persistence of embryonic pattern of hepatocaval venous junction and patent ductus venosus in Budd-Chiari syndrome.

We report an autopsy study on a case of Budd-Chiari syndrome (BCS) in a 44-year-old woman. Dissection showed that the outlets of the right hepatic vein (HV) and of the common trunk of the middle and left HVs appeared as two small depressed areas with narrow ostia. Histological examination showed recent thrombosis of the tributaries of the HVs and centrilobular congestion with necrosis of the hepatic parenchyma. The juxtacaval portions of the major HVs showed a cuneiform shape, because of marked dilation, with thread-like ostia, and multiple small outlets of minor hepatic veins were also present. The coexistence of patent ductus venosus may have prevented the development of the hepatocaval venous junction, with persistence of the embryonic pattern, composed of multiple small channels draining into the right hepatocardiac channel. The unusual hepatocaval venous junction may have predisposed to thrombosis of the HVs, causing BCS.

Adult↗
PubMed2006

Endoscopic treatment of pseudosarcomatous squamous carcinoma of the esophagus: case report and personal experience.

Spindle cell (or pseudosarcomatous) squamous carcinoma (PSC) is a rare malignant neoplasm of the esophagus, potentially capable of causing lymph node and distant metastases. Indications for surgery are the same as for squamous cell carcinoma (SCC) of the esophagus. The aims of this paper were to report a case of endoscopically treated PSC and to review our experience of surgically-treated patients with PSC in order to identify patients potentially suitable for endoscopic treatment. In our series of 4,460 patients with carcinoma of the esophagus observed between 1980 and 2003, 28 (0.6%) had the histological features of PSC. One had a PSC histologically confirmed (8cm-long polyp with a 3cm-large base) and endoscopically treated for high surgical risk. The patient had a close follow-up with endoscopic biopsies and ultrasonography with no local recurrence at 3 years. The overall survival rate was 22% for PSC and 17% for SCC (P = n.s.); after 5 years, the survival rates were 22% and 13%, respectively (P = n.s.). In our opinion the limited tendency to parietal infiltration and the good chance of disclosure in an early stage with endoscopic ultrasonography, justify non-surgical solutions in patients with a high surgical risk, possibly associated with adjuvant chemo- and radiotherapy since lymph node involvement is reported in 50% of cases. The limited number of patients with PSC involved in the present series prevent any significant statistical comparisons between the different groups, but the survival rates were roughly the same in the nonsurgical curative therapy as in the curative resection group, while the chances of survival were significantly lower in patients given palliative surgery and or non-curative treatments (P < 0.05).

Aged, 80 and over↗
PubMed2006

Sertoli cell tumor: a rare case in an elderly patient.

Sertoli-Leydig cell tumors constitute < 1% of ovarian tumors, mostly in young women with virilization; however, not all present endocrine manifestations. A 72-year-old female presented with an abdominal mass and no signs of virilization. Total abdominal hysterectomy with bilateral salpingo-oophorectomy, omentectomy and selective pelvic lymphadenectomy was performed. The pathologic diagnosis was poorly-differentiated sex cord-stromal tumor with Sertoli cells. No adjuvant chemotherapy or radiation was administered. At 12-month follow-up the patient showed no evidence of disease.

Age Factors↗
PubMed2005

Morphogenesis of the posterior inferior cerebellar artery with three-dimensional reconstruction of the late embryonic vertebrobasilar system.

The posterior inferior cerebellar artery (PICA) shows the most variable course among the cerebellar arteries, mainly at the level of the lateral medullary segment. Based on the correlation between the level of origin and the characteristics of the lateromedullary segment, we have proposed three patterns of course of the PICA. With the aim of understanding their embryological basis we review the interrelations between the developing cerebellum and the primitive hindbrain arterial plexus through the analysis of transverse serial sections of human embryos of 22.5 and 23 mm crown-rump length. Three-dimensional reconstruction of the vertebrobasilar system has been performed to study the morphology of the vascular networks. The cerebellar primordium is vascularized by the metencephalic plexus that will form the basilar artery and the superior cerebellar arteries. Due to the development of the pontine flexure the rhomboid lips approach and the cerebellum comes into contact with the myelencephalon; thus the myelencephalic plexus represents an acquired source of vascularization for the cerebellum with respect to the metencephalic plexus. The examination of the transverse sections shows that the vertebral and basilar arteries, superior cerebellar arteries, anterior inferior cerebellar arteries, and primitive lateral vertebrobasilar anastomoses are well recognizable. The three-dimensional reconstruction of the vessels shows that the PICA is not yet defined due to the persistence of a plexus of many thin vessels at the level of the lateral aspect of the myelencephalon, indicating that its origin and course are established at the end of the embryonic period. Based on the evolution of the primitive hindbrain plexus, we suggest that in synchrony with the progressive descent of the cerebellum the branches of the myelencephalic plexus succeed with a rostrocaudal progression in feeding the cerebellum and the morphogenesis of the PICA results from the selection of portions of this plexus. The high origin of the PICA from the basilar artery could be ascribed to its development from a rostral collateral of the plexus due to an early development of the vessel at the beginning of its embryonic lifetime. Moreover, the three patterns of course of the PICA could reflect the variable retention of the primitive lateral vertebrobasilar anastomosis in the trunk of the definitive PICA, which may be related to its level of origin.

Arteries↗
PubMed2005

Histopathology of carotid body in heroin addiction. Possible chemosensitive impairment.

AIMS: To perform a morphometric analysis of carotid bodies in opiate addicts. METHODS AND RESULTS: Carotid bodies were sampled at autopsy from 35 subjects who died of heroin intoxication (mean age 26 years), and from eight young (22 years) and eight older subjects (66.5 years) who died of trauma. Sections were stained with haematoxylin-eosin, azan-Mallory, and double-labelling immunohistochemistry with antineuronal specific enolase and anti-S100, to count type I and type II cells. Interlobular and intralobular connective tissue was increased both in the opiate cases (43.45 +/- 6.79%, P < 0.001, and 13.34 +/- 5.72%, P < 0.001, respectively) and older cases (46.67 +/- 1.65%, P < 0.001, and 9.62 +/- 2.11%, P < 0.05, respectively) compared with young cases (33.17 +/- 6.41% and 4.33 +/- 1.84%, respectively). The percentage of type II cells in the opiate cases (51.6 +/- 7.3%, P < 0.001) and in the older controls (49.0 +/- 7.2%, P < 0.01) was higher than in the young cases (37.9 +/- 3.0%). Among type I cells, the light cell percentage in the opiate cases (65.85 +/- 11%, P < 0.001) was reduced with respect to the two control groups (82.8 +/- 5.34%, young; 81.62 +/- 8.58%, older). CONCLUSIONS: The increases in connective tissue and type II cells are similar to findings in ageing and chronic pulmonary disease, and may be ascribed to glomic hypoxia. A direct action of opiates should be taken into account for the decrease in light cells in heroin addiction. The histopathological changes in the carotid body, by impairing chemosensivity, may play a role in the fatal cardiorespiratory derangement of heroin addicts.

Adult↗
PubMed2004

Intraepithelial G3 adenocarcinoma of the endometrium after tamoxifen treatment.

CASE REPORT: In this paper we describe a case of endometrial carcinoma observed in a post-menopausal patient who was treated with tamoxifen for 5 years after a mastectomy for cancer. She came to our department because of vaginal bleeding 2 years after the end of tamoxifen treatment. TREATMENT: She underwent hysteroscopy and a D and C. A polypoid endometrium completely filled the uterine cavity and was carefully removed by curettage; histology showed a highly undifferentiated neoplasia with a component of serous adenocarcinoma, which was likely to originate from endometrial polyps. OUTCOME: The patient underwent radical hysterectomy, but no residual tumor was found in the uterus or in the tubes, ovary, or pelvic nodes, in spite of its low differentiation grade and high potential aggressiveness, and even though the patient was already symptomatic. Two years after surgery the patient is disease free, which is consistent with the evaluation of the surgical specimen, but unusual in poorly differentiated neoplasms.

Adenocarcinoma↗
PubMed2003

The course of the posterior inferior cerebellar artery may be related to its level of origin.

The course of the posterior inferior cerebellar artery (PICA) was analyzed with reference to its origin and relationships with the medullary and cerebellar surfaces and the adjacent cranial nerves in 40 brains after the injection with acrylic resins of the vertebrobasilar system. In 42.5% of instances, the PICA originated from the lateral medullary segment of the vertebral artery (VA), in 32.5% from its premedullary segment, in 22.5% from the basilar artery (BA), and in 2.5% it was absent. With reference to the level of origin, three patterns of course for the lateral medullary segment of the PICA can be outlined. (1) When it arises from the lateral medullary segment of the VA, it passes below the hypoglossal nerve, and the lateral medullary segment may form a loop with an anterosuperior convexity towards the pontomedullary sulcus (41%), or it may follow a rectilinear course (41%). It passes at the level of the accessory nerve. The tonsillomedullary (TM) segment shows a caudal loop and the telovelotonsillary (TVT) has a cranial loop. (2) When the PICA arises from the BA, it passes above the hypoglossal nerve. The lateral medullary segment forms a loop with lateral convexity (78%) and passes above or through the glossopharyngeal nerve, frequently showing a recurrent course among the roots of the IX, X, or XI cranial nerve. The TM and the TVT segments do not have loops. (3) When the PICA arises from the premedullary segment of the VA, it passes above, below, or through the rootlets of the hypoglossal nerve. In the lateral medullary segment, it follows a rectilinear course (54%) and passes the plane formed by the IX, X, and XI cranial nerves at an intermediate level with respect to the other two patterns. The TM and the TVT segments show caudal and cranial loops. The different origins and courses of the PICA derive from the selection of different branches of the primitive vertebrobasilar plexus during the development of the cerebellum. The existence of an embryologic correlation between the course of the PICA and its level of origin may be useful in the evaluation of its angiographic anatomy.

Adolescent↗
PubMed2003

A short course of dissection for second-year medical students at the School of Medicine of Padova.

A "Short course of dissection" was introduced in 1999 for the second-year medical students at the University of Padova. The course aims to offer a direct experience of practical anatomy despite a shortage of time for anatomy courses and lack of availability of cadavers. The course is optional and is planned for 40 students, subdivided into eight working groups. It consists of five sessions on the following topics: the viscera of the male pelvis; the viscera of the female pelvis; the kidney, the testis and spermatic cord; the thorax and abdomen; the brain. Each session lasts 3 hours and is organized as follow: (A) Theory: Teacher: concise review of the systematic and topographic anatomy of the selected topic (20 min); Students: analysis of a dissection guide (20 min). (B) Practice: Students: identification of the viscera and vascular and nervous structures, through inspection and palpation (15 min); step-by-step dissection following the worksheet (80 min); presentation of the visceral blocks as prosections under a closed-circuit telecamera (anatomical variability) (30 min); Teachers and students: three-dimensional conceptualization tests (15 min). At the end of the 2000 and 2001 courses, a questionnaire was administered to the students and the results confirm the usefulness of dissection for developing a three-dimensional knowledge of anatomy. In our opinion the main guidelines in planning a short course of dissection are: (1) selection of the topics, aimed at allowing experience of the gross anatomy of single viscera, fascia and serosa as well as the evaluation of the topographical relationships between parts of different systems including the local vessels and nerves; (2) preparation of a worksheet, presenting in 10-15 points concise instructions for the step-by-step progression from inspection to palpation and dissection of the anatomical structures of the visceral block; (3) direct dissection, brief and selective, by students; (4) clinical correlation; (5) motivational teachers, who stimulate the active involvement of students in "learning by doing" and also "learning how to do".

Anatomy↗
PubMed2003

Pivotal role of the sub-supracardinal anastomosis in the development and course of the left renal vein.

A retroaortic left renal vein is encountered frequently in the dissecting room and in radiological investigations. A number of recent reports of this variation led us to review the development of the renal veins and the inferior vena cava to understand its etiology. For further insight, we also examined our collection of serial sections of cat embryos. In human embryos of about 15 mm the "renal collar," a venous ring around the aorta, is formed by anastomoses between subcardinal and supracardinal veins. The ventral part of the "renal collar" is formed from the intersubcardinal anastomosis, the dorsal part from the intersupracardinal anastomosis and the lateral parts from the sub-supracardinal anastomoses. The primitive renal veins drain venous blood from the metanephros into the sub-supracardinal anastomoses. A retroaortic left renal vein would form if the dorsal part of the sub-supracardinal anastomosis and the intersupracardinal anastomosis persist whereas the ventral part of the sub-supracardinal anastomosis and the intersubcardinal anastomosis regress.

Animals↗
PubMed2003

Workshop in clinical anatomy for residents in gynecology and obstetrics.

A workshop in the clinical anatomy of the female pelvic viscera has been part of the training program for the first year residents in Gynecology and Obstetrics at the University of Padova since the 1999-2000 academic year. The purpose of the workshop is to offer a direct experience of practical anatomy despite a shortage of cadavers. It is designed for six residents who work in three teams on three specimens. The anatomical specimens are unembalmed, unfixed, female pelvic visceral blocs that are harvested from the cadavers 24 hr after death. They are stored at -12 degrees C and removed from the freezer 12 hr before the workshop. The workshop is 3 hr in length and has two parts: one on theory and one practical. In the theoretical section (30 min), the teacher presents the topographical anatomy of the specimens and the residents analyze a clinically oriented worksheet. In the practical section (2 hr), the residents identify viscera, vessels, and nerves through inspection and palpation, and then a step-by-step dissection is carried out. In the last section (30 min), the workshop includes presentations on the three specimens that illustrate anatomical variability and assess knowledge of topographical anatomy. For many residents, this is the first practical experience of the anatomy of the female pelvic viscera because the anatomical courses for medical students do not include direct dissection by students. The unfixed viscera preserves the natural characteristics of the different tissues that exhibit the aspects of living organs, such as color, softness, and pliability, enhancing the knowledge of anatomy. The worksheet is structured as a guide to the anatomical basis of physical examination through inspection and palpation of the viscera. It also introduces the residents to the surgical anatomy of the female pelvis through a brief and selective dissection focused on the relationship between the different regional systems.

Anatomy↗
PubMed2002

Role of acid and bile reflux in development of specialised intestinal metaplasia in distal oesophagus.

BACKGROUND: Barrett's oesophagus is defined as specialised intestinal metaplasia in the distal oesophagus, regardless of extension. AIM: To study distal oesophagus function, and acid and bile exposure in patients with Long Segment (>3 cm), Short Segment (1 to 2 cm) and Ultra-short Segment (<1 cm) Barrett's Oesophagus, and in patients with gastro-oesophageal reflux disease without intestinal metaplasia. PATIENTS: Study population comprised 17 patients with Long, 8 with Short, 9 with Ultra-Short Segment Barrett's oesophagus, 32 with reflux disease and 12 healthy volunteers. METHODS: Patients were evaluated by manometry and by 24-hour pH and bile monitoring. RESULTS: Patients with intestinal metaplasia had greater acid exposure of the distal oesophagus than healthy volunteers. Patients with Long Segment Barrett's oesophagus had a longer history of symptoms, worse lower oesophageal sphincter pressures and longer bile and acid exposure than the other patients. Long Segment Barrett's oesophagus was predicted by low oesophageal pressure and increased bile exposure, age and male sex. CONCLUSION: Acid exposure in the distal oesophagus is probably the aetiological factor behind intestinal metaplasia, but a severely damaged antireflux barrier and bile in the refluxate are necessary for Long Segment Barrett's Oesophagus to develop.

Adult↗
PubMed2001

MAGE, BAGE, and GAGE gene expression in patients with esophageal squamous cell carcinoma and adenocarcinoma of the gastric cardia.

BACKGROUND: The MAGE, BAGE, and GAGE gene families code for distinct, tumor specific antigens that are recognized by cytotoxic T lymphocytes in the context of HLA molecules. The purpose of this study was to analyze MAGE, BAGE, and GAGE gene expression in the two major histologic types of esophageal carcinoma, squamous carcinoma (ESCc) and adenocarcinoma (CAc), and to correlate their expression patterns with the principal prognostic parameters and long term survival. METHODS: Gene expression was analyzed in surgical samples from 24 patients with ESCc and 24 patients with CAc by reverse transcriptase-polymerase chain reaction amplification (RT-PCR). None of the patients had received preoperative chemotherapy or radiotherapy, and all were followed until death or for a minimum of 4 years. RESULTS: Sixteen ESCc samples (67%) and 9 CAc samples (37.5%) expressed at least one of the genes under study. The expression of each MAGE gene in the two histologic types was not significantly different, with the exception of MAGE-4, which was expressed more in ESCc samples than in CAc samples. BAGE and GAGE expression was rather low and, in every case, was associated with the expression of at least one MAGE gene. CONCLUSIONS: In the group as a whole, and in both ESCc and CAc subgroups, no significant correlation emerged between the expression of any gene and prognostic parameters, such as pathologic tumor, lymph node, or disease stage. Nevertheless, BAGE or GAGE expression was related significantly to a poor prognosis, whereas the expression of MAGE genes (in the absence of BAGE and GAGE expression) was related significantly to a good prognosis.

Adenocarcinoma↗
PubMed2001

Fractal analysis of lumbar vertebral cancellous bone architecture.

Osteoporosis is characterized by bone mineral density (BMD) decreasing and spongy bone rearrangement with consequent loss of elasticity and increased bone fragility. Quantitative computed tomography (QCT) quantifies bone mineral content but does not describe spongy architecture. Analysis of trabecular pattern may provide additional information to evaluate osteoporosis. The aim of this study was to determine whether the fractal analysis of the microradiography of lumbar vertebrae provides a reliable assessment of bone texture, which correlates with the BMD. The lumbar segment of the spine was removed from 22 cadavers with no history of back pain and examined with standard x-ray, traditional tomography, and quantitative computed tomography to measure BMD. The fractal dimension, which quantifies the image fractal complexity, was calculated on microradiographs of axial sections of the fourth lumbar vertebra to determine its characteristic spongy network. The relationship between the values of the BMD and those of the fractal dimension was evaluated by linear regression and a statistically significant correlation (R = 0.96) was found. These findings suggest that the application of fractal analysis to radiological analyses can provide valuable information on the trabecular pattern of vertebrae. Thus, fractal dimensions of trabecular bone structure should be considered as a supplement to BMD evaluation in the assessment of osteoporosis.

Adult↗
PubMed2001

Prevalence of intestinal metaplasia in the distal oesophagus, oesophagogastric junction and gastric cardia in symptomatic patients in north-east Italy: a prospective, descriptive survey. The Italian Ulcer Study Group "GISU".

BACKGROUND: Incidence of adenocarcinoma of distal oesophagus and gastric cardia, probably arising from areas of intestinal metaplasia, has been increasing rapidly. AIMS: To define prevalence of intestinal metaplasia of distal oesophagus, oesophagogastric junction and gastric cardia and to evaluate potential associated factors, by means of a prospective multicentre study including University and teaching hospitals, and primary and tertiary care centres. PATIENTS: Each of 24 institutions involved in study enrolled 10 consecutive patients undergoing first-time routine endoscopy for dyspeptic symptoms. METHODS: Patients answered symptom questionnaires and underwent gastroscopy Three biopsies were taken from distal oesophagus, oesophago-gastric junction and gastric cardia, and were stained with haematoxylin and eosin. Specimens were also evaluated for Helicobacter pylori infection. RESULTS: A total of 240 patients (124 male, 116 female; median age 56 years, range 20-90) were enrolled in study. Intestinal metaplasia affected distal oesophagus in 5, oesophago-gastric junction in 19 and gastric cardia in 10 patients. Low-grade dysplasia was found at distal oesophagus and/or oesophago-gastric junction of 3/24 patients with intestinal metaplasia vs 2/216 without intestinal metaplasia (p<0.05). A significant association was found between symptoms and presence of intestinal metaplasia, regardless of location, and between Helicobacter pylori infection and intestinal metaplasia at oesophago-gastric junction. CONCLUSIONS: Intestinal metaplasia of distal oesophagus, oesophagogastric-junction and gastric cardia is found in a significant proportion of symptomatic patients undergoing gastroscopy and is associated with dysplasia in many cases. Although prevalence of dysplasia seems to decrease when specialized columnar epithelium is found in short segment, or even focally in oesophago-gastric junction, these small foci of intestinal metaplastic cells may represent source of most adenocarcinomas of cardia.

Barrett Esophagus↗
PubMed2001

ANG II potentiates mitogenic effect of norepinephrine in vascular muscle cells: role of FGF-2.

We examined the possible cooperation between norepinephrine (NE) and ANG II on proliferation of cultured vascular smooth muscle cells (VSMCs) and the involved cellular mechanisms. Nanomolar NE concentrations stimulated VSMC proliferation through a prazosin-sensitive effect. The pretreatment of cells with 100 nM ANG II for 24 h significantly potentiated the NE-induced VSMC proliferation; this potentiating effect of ANG II was blocked by losartan but was unaffected by the AT(2) receptor antagonist PD-123177. ANG II pretreatment also potentiated the increase in inositol phosphate turnover and upregulated the cell expression of fibroblast growth factor (FGF-2) induced by NE. Anti-FGF-2 neutralizing antibodies prevented the potentiating effect of ANG II on NE-induced cell growth. Both ANG II and NE stimulated extracellular signal-related kinase (ERK1) activation, but an ANG II potentiation of the effect of NE on ERK1 activity was not detectable. Moreover, ANG II significantly increased protein synthesis but did not potentiate the hypertrophic effect of NE. These findings demonstrate that ANG II and NE cooperate in promoting VSMC growth and that FGF-2 upregulation is involved in this effect.

Angiotensin II↗
PubMed2001

alpha(1D)-adrenoceptors cause endothelium-dependent vasodilatation in the rat mesenteric vascular bed.

The vasodilator activity of alpha(1)-adrenoceptor agonists was tested in the rat mesenteric vascular bed (MVB), and the mechanism involved was investigated in cultured endothelial cells isolated from the bovine coronary vascular bed. In preparations preconstricted by U46619, noradrenaline and phenylephrine induced a slight relaxant effect at nanomolar concentrations. This effect was abolished in endothelium-denuded preparations and in preparations pretreated with 100 microM N(omega)-nitro-L-arginine methyl ester plus 3 microM indomethacin. Both the phospholipase C inhibitor U73122 and the endoplasmic reticulum Ca(2+)-ATPase inhibitor thapsigargin inhibited the vasorelaxant effect of phenylephrine. The cellular level of inositol monophosphate (IP(1)) in bovine endothelial cells doubled after a 15-min exposure to 0.03 to 0.1 nM phenylephrine. The activity of cNOS was significantly increased following exposure to the same concentrations of phenylephrine. Both chloroethylclonidine and the selective alpha(1D)-adrenoceptor antagonist BMY 7378 reduced, in a concentration-dependent manner, the relaxant effect induced by phenylephrine, whereas the selective alpha(1A)-adrenoceptor antagonist (+)-niguldipine was ineffective. BMY 7378 also blocked the cNOS activation induced by phenylephrine. Conversely, the increase in perfusion pressure induced by micromolar concentrations of phenylephrine was blocked by 1 nM (+)-niguldipine, but was unaffected by BMY 7378. These findings demonstrate that nanomolar concentrations of phenylephrine, which are devoid of any contractile effect, induced a slight endothelium-dependent vasorelaxation in the rat MVB through the stimulation of alpha(1D)-adrenoceptors, located on endothelial cells, which act through phospholipase C stimulation, followed by IP(1) generation, and nitric-oxide synthase activation. Conversely, the increase in perfusion pressure induced by micromolar concentrations of phenylephrine is attributable to the stimulation of alpha(1A)-adrenoceptors.

Adrenergic alpha-1 Receptor Agonists↗