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M Zanella

Publications and source records attributed to M Zanella.

At least 19 recordsLinked to original sources
PubMed2001

Managing uncertainty in diagnosis of acute coronaric ischemia.

The paper presents the reasoning mechanism of COR, a knowledge-based system (KBS) able to provide support for the diagnosis of coronaric ischemia by integrating the interpretation of chest pain, 12-lead ECG, and bio-marker concentrations. Chest pain features are collected interactively through a questionnaire. The ECG signal is acquired in SCP format. Any set of bio-markers can be considered. Data input is incremental and possibly incomplete. Reasoning is based on revised uncertainty calculus, which allows a formal treatment of verbally expressed uncertainty concerning both input data and diagnostic rules. Each diagnosis is supplemented by a linguistic label, expressing the plausibility of the disease identified, given the symptoms observed.

Artificial Intelligence↗
PubMed2001

Papillary thyroid carcinoma of the thyroglossal duct cyst: comparative cytohistologic and immunochemical study of 2 new cases and review of the literature.

We report a cytohistologic and immunohistochemical study of 2 cases of papillary thyroid carcinoma occurring in a thyroglossal duct cyst. The patients were a 21-year-old woman and a 48-year-old man. Needle aspiration cytology smears were consistent with papillary thyroid carcinoma. The Sistrunk procedure was done. Papillary carcinoma was found within a thyroglossal duct cyst. In 1 case, the tumor spread outside the cyst. Follow-up was uneventful in both patients (2 and 9 years, respectively). Our results would indicate that papillary carcinoma of thyroglossal duct cyst, though indistinguishable from its thyroid homologue, has a more indolent course and could therefore be singled out as a clinicopathologic entity. Needle aspiration cytology reliably assists in planning patient management.

Adult↗
PubMed2001

Cigarette smoking is a risk factor for nephropathy and its progression in type 2 diabetes mellitus.

Cigarette smoking is a risk factor for diabetic nephropathy in Type 1 diabetes (T1DM); a few reports support this possibility in Type 2 diabetes (T2DM) as well. Since heterogeneity among populations could exist, we investigated the association of cigarette smoking and nephropathy, and progression of nephropathy in Italian T2DM patients. A retrospective study was conducted in 273 long-duration T2DM subjects with a 3-year follow-up in the out-patient clinic, and at least one access per year. Albumin excretion rate, serum creatinine, and a number of other parameters implicated in the development of diabetic renal disease were evaluated. Progression of nephropathy was defined as the passage from different stages of renal involvement (no renal derangement, microalbuminuria, proteinuric disease or severe nephropathy). At baseline, 13.2% of the subjects had microalbuminuria, and 3.7% proteinuric disease. Microalbuminuria and proteinuric disease were more frequent in actual smokers than in non- and former smokers (chi2=8.35; p=0.015). Progression of nephropathy was less common in non- and former smokers than in smokers (31 of 134, 23%, and 15 of 67, 22%, and 30 of 72, 42%, respectively; chi2=9.32;p=0.009). From logistic regression analysis, smoking (p=0.0012) emerged as the most important factor associated with progression of nephropathy, followed by packyears (p=0.011), HbA1c mean value at follow-up (p=0.024), and total cholesterol (p=0.038). In conclusion, cigarette smoking is a risk factor for progression of nephropathy also in Italian T2DM patients; reducing or quitting smoking should be part of the therapy or of the preventive measures in these patients and their relatives.

Aged↗
PubMed2000

Impact of biofeedback-induced cardiovascular stability on hemodialysis tolerance and efficiency.

BACKGROUND: Hypotension is caused by a drop in blood volume during ultrafiltration, followed by vasoconstriction and reduced perfusion in some regions of the body. METHODS: We carried out a prospective controlled crossover study on 12 hypotension-prone patients with two different modalities: (A) acetate-free hemodiafiltration with standard ultrafiltration control, and (B) acetate-free hemodiafiltration with monitoring of blood volume and automatic biofeedback with machine-driven adjustments on ultrafiltration and dialysate conductivity. We measured urea Kt/V and equilibrated Kt/V (eKt/V), urea rebound, and urea removal. Hypotensive episodes and interventions were recorded. RESULTS: In group B, fewer hypotensive episodes were recorded (24 out of 72 in group B vs. 59 out of 72 in group A). Saline infusion was required in 57 cases in group A and 15 cases in group B. Urea Kt/V was 1.34 +/- 0.08 in group A and was 1.26 +/- 0.06 in group B; eKt/V was much higher in group B (1.12 +/- 0.05) than in group A (1.03 +/- 008). A significantly higher rebound was observed in group A (14.2 +/- 2.7%) compared with group B (6.4 +/- 2.3%). Discussion. A greater solute sequestration seems to occur during hemodialysis with hypotension. This results in lower eKt/V, enhanced postdialytic rebound, and lower solute removal. Higher efficiency can be observed when dialysis is carried out smoothly and cardiovascular stability is maintained. We conclude that new systems for blood volume monitoring and automatic biofeedback may not only reduce the number of hypotensive episodes during dialysis, but may also contribute to significantly increase the efficacy of the treatment.

Adult↗
PubMed1999

Embryonal "Botryoid" rhabdomyosarcoma of the larynx: a clinicopathologic and immunohistochemical study of two cases.

Two cases of embryonal rhabdomyosarcoma of the larynx are reported. The tumors occurred in a 16-year-old boy and in a 66-year-old man. They manifested clinically with nonspecific symptoms, including voice hoarseness and sense of throat fullness. Treatment consisted of total and partial laryngectomy, respectively. Grossly, both lesions had an exophytic growth pattern and microscopically featured a proliferation of small round to oval cells. Cell cytoplasms were occasionally stainable and fibrillary. Quite often, tumor cellularity was denser beneath the covering mucosa, recalling a "cambium layer" pattern. Tumor cells immunoreacted for desmin, actins, myoglobin, and sarcomeric actin; no immunostaining was noted for epithelial markers. No further antitumoral treatment was administered after surgery. There has been no recurrence of tumor at 2 and 10 years, respectively. Based on our series and the available literature, it seems that rhabdomyosarcoma of the larynx pursues a less-aggressive course than that seen in the homonimic juvenile or adult soft tissue lesion. Surgery alone appears to be a valid treatment option, especially when a polypoid, or "botryoid" gross pattern, coupled with the embryonal small cell histotype is encountered. In light of these findings, it is suggested that botryoid rhabdomyosarcoma of the larynx may deserve a specific consideration among the various laryngeal mesenchymal malignancies.

Adolescent↗
PubMed1999

Pulmonary thromboembolism following calf cellulitis: report of an unusual complication of dog bite.

We report a case of a 75-year-old woman who died of pulmonary thromboembolism following a dog bite to the calf. The bite caused laceration of the skin and gangrenous cellulitis of leg soft tissues. Six days after hospitalization, the patient died suddenly, despite early antibiotic and heparin administration. Postmortem examination revealed extensive thrombosis of the deep veins of the calf and massive thromboembolism of the main pulmonary arteries.

Aged↗
PubMed1999

Migration of langerhans cells and dermal dendritic cells in skin organ cultures: augmentation by TNF-alpha and IL-1beta.

Migration from sites of antigen encounter to lymphoid organs is essential to the strong immunogenic function of dendritic cells (DC). In the skin, migration proceeds through dermal lymphatic vessels and is regulated in an incompletely understood way by inflammatory mediators. We studied the effects of tumor necrosis factor alpha (TNF-alpha) and interleukin-1beta (IL-1beta) in mouse skin organ cultures by direct enumeration of migrating DC and by immunohistochemistry. (1) Neutralizing antibodies to TNF-alpha and IL-1beta inhibited migration of DC, also in human skin explants (TNF-alpha). (2) TNF-alpha at low concentrations (50 U/mL) and IL-1beta (50-3000 U/mL) augmented migration to about 150% of spontaneous migration. (3) High concentrations of TNF-alpha (5000 U/mL) inhibited migration by approximately 50%. (4) DC migration from skin explants of TNF-alpha/lymphotoxin-alpha double-deficient mice and TNF-receptor type 1 and 2 double knockout mice was not impaired. (5) TNF-alpha effects were neutralized by anti-IL-1beta, and vice versa. We conclude that in normal animals both TNF-alpha and IL-1beta are required for DC migration to occur. In the complete absence of one cytokine (TNF-alpha), however, backup mechanisms step in.

Animals↗
PubMed1998

Pseudoangiomatous hyperplasia of the mammary stroma: true entity or phenotype?

We report the clinical and pathologic features seen in 14 cases of pseudoangiomatous hyperplasia of the mammary stroma. The lesion manifested as a discrete palpable lump in twelve women and two men. The excisional biopsy specimens showed firm, circumscribed grey-tan lesions measuring from 3 to 5.5 cm in largest dimension. Histologic study revealed diffuse, anastomosing, enlongated slits with open lumina, covered by spindle cells with bland nuclei and no mitotic activity. Strong reactivity for vimentin and CD34 was noted. Smooth muscle actin was focally noted in most cases. Immunostains for other markers, including CD31 and factor VIII related antigen was negative. Spindle cells from two cases expressed both estrogen and progesterone receptors. In all the cases, there was some degree of glandular hyperplasia accompanying the stromal changes. Fibroadenoma or fibrocystic disease were also common features. Our study confirms that pseudoangiomatous hyperplasia of mammary stroma represents a proliferation of local myofibroblasts, likely related to a hormonal stimulus. The wide range of associated changes of breast parenchyma further indicates that this lesion may represent a local, non specific change rather than a true clinico-pathologic entity.

Actins↗
PubMed1998

Polypoid osteosarcoma of the left atrium: report of a new case with autopsy confirmation and review of the literature.

We describe a new case of heart osteosarcoma manifesting as a large polypoid mass of the left atrium. Clinically, the lesion presented with dyspnea, syncopal attacks, and fever. Ultrasound scans of the heart were suggestive of a cardiac myxoma, although some imaging features could retrospectively indicate a malignant neoplasm. In particular, the lesion was relatively immobile, did not show the characteristic myxoma motion during the heart cycle, and extended into the left pulmonary veins. Exploratory thoracotomy showed a nonresectable polypoid mass of the left atrium widely infiltrating the myocardium and the epicardium, histological features of a polymorphic sarcoma. The patient died 5 months after presentation with diffuse metastases. At autopsy, a 5-cm polypoid tumor was seen protruding into the left atrium. Neoplastic infiltration of the atrial myocardium, pericardium, and pulmonary veins was evident. Extensive metastatic deposits were observed in numerous sites, including the skin, lung, liver, and brain. Microscopically, a spindle cell sarcoma forming malignant osteoid was seen, admixed with areas indistinguishable from myxoid and pleomorphic malignant fibrous histiocytoma. This case provides further evidence that although rare, osteosarcoma of the heart usually presents as a polypoid mass of the left atrium and is histologically characterized by conspicuous polymorphism. It is associated with a poor prognosis and rapid appearance of distant metastases. Although at echocardiography it may mimic a myxoma, subtle features such as tumor extension into pulmonary veins and main origin from nonseptal atrial walls suggest the presence of a nonmyxomatous tumor and a preoperatory diagnosis of aggressive malignant disease.

Adult↗
PubMed1998

Entry into afferent lymphatics and maturation in situ of migrating murine cutaneous dendritic cells.

An important property of dendritic cells (DC), which contributes crucially to their strong immunogenic function, is their capacity to migrate from sites of antigen capture to the draining lymphoid organs. Here we studied in detail the migratory pathway and the differentiation of DC during migration in a skin organ culture model and, for comparison, in the conventional contact hypersensitivity system. We report several observations on the capacity of cutaneous DC to migrate in mouse ear skin. (i) Upon application of contact allergens in vivo the density of Langerhans cells in epidermal sheets decreased, as determined by immunostaining for major histocompatibility complex class II, ADPase, F4/80, CD11b, CD32, NLDC-145/DEC-205, and the cytoskeleton protein vimentin. Evaluation was performed by computer assisted morphometry. (ii) Chemically related nonsensitizing or tolerizing compounds left the density of Langerhans cells unchanged. (iii) Immunohistochemical double-staining of dermal sheets from skin organ cultures for major histocompatibility complex class II and CD54 excluded blood vessels as a cutaneous pathway of DC migration. (iv) Electron microscopy of organ cultures revealed dermal accumulations of DC (including Birbeck granule containing Langerhans cells) within typical lymphatic vessels. (v) Populations of migrating DC in organ cultures upregulated markers of maturity (the antigen recognized by monoclonal antibody 2A1, CD86), but retained indicators of immaturity (invariant chain, residual antigen processing function). These data provide additional evidence that during both the induction of contact hypersensitivity and in skin organ culture, Langerhans cells physically leave the epidermis. Both Langerhans cells and dermal DC enter lymphatic vessels. DC mature while they migrate through the skin.

Animals↗
PubMed1997

Gestational squamous cell carcinoma of the breast: an unusual mammary tumor associated with aggressive clinical course.

We report two cases of squamous carcinoma of the breast detected during the gestational period. One woman was post-partum and lactating; one was in the first trimester of pregnancy. The lesions were clinically palpable, multifocal, and measured more than 5 cm in their largest dimension; both had a cystic appearance. They were treated with radical mastectomy. One patient received pre-operatory chemotherapy. Histologically, the tumors were poorly differentiated squamous cell carcinomas. No areas of ordinary duct differentiation were seen. Lymph nodes contained metastatic squamous carcinoma in both cases. Tumor cells were negative for estrogen and progesterone receptors. Also, they expressed a high proliferative index and several markers of tumor progression, including cErb-B2, p53 protein, bcl-2, and epidermal growth factor receptor. One patient died of tumor 5 months following breast surgery and had extensive metastases proven at autopsy. The other patient had evidence of pulmonary metastases: following cisplatin therapy, she underwent clinical remission. This study shows that squamous carcinoma of the breast may occur in pregnant or lactating women: it appears clinically distinguishable from the non-gestational type that is usually associated with a better prognosis and occurs in peri- or postmenopausal women.

Adult↗
PubMed1997

Pseudomesotheliomatous angiosarcoma: a pleuropulmonary lesion simulating malignant pleural mesothelioma.

We report two cases of autopsy confirmed angiosarcoma in adult males, presenting as diffuse pleuropulmonary tumours and simulating malignant mesothelioma. Both the lesions grew along the serosal surfaces and were characterized by variably thick rinds of tissue encasing the lung. The pulmonary parenchyma showed diffuse, dark red, subpleural consolidations and multiple cavitations. Histologically, the lesions were composed by atypical spindle and polygonal, epithelioid cells showing rudimentary vascular differentiation and exhibiting strong positivity for factor VIII, CD31, CD34 and vimentin, We conclude that angiosarcoma may present with preponderant or exclusive involvement of pleura and peripheral lung and that it should be added to the list of tumours capable of simulating malignant mesothelioma.

Aged↗
PubMed1997

Intrapericardial thymoma: report of two incidental autopsy cases and review of the literature.

OBJECTIVES: To report the pathologic features of intrapericardial thymoma and discuss their possible clinical relevance. DESIGN: Retrospective evaluation of autopsy cases and the available clinical records. SETTING: A large autopsy population (>31,000 postmortem examinations between 1980 and 1995) in an Italian general hospital. RESULTS: Two cases of thymoma showing an exclusive intrapericardial growth were retrieved from autopsy files. The patients were 61 and 82 years of age, both were women, and both were referred to the hospital with terminal conditions due to either neoplastic or chronic diseases. Myasthenia gravis and/or immunologic dysfunctions were not noted, although one of the patients had serum hypogammaglobulinemia. Roentgenography showed enlargement of mediastinal profiles and suggested cardiomegaly. At autopsy, tumors were bulky, noninvasive, and from 6 to 10 cm in largest dimension. Histologically, they were spindle cell "medullary" thymomas, frequently showing cell arrangement around microcystic spaces. They were strongly immunoreactive for epithelial markers. CONCLUSIONS: This study confirms that thymomas may occur in the pericardium. Tumor-related symptoms may be overlooked owing to concomitant heart disease or equivocal instrumental features, especially in the absence of immune system disturbances. Based on these premises, they may deserve a specific distinction in the expanding chapter of ectopic thymomas.

Aged↗
PubMed1997

Beta 2-microglobulin removal by synthetic dialysis membranes. Mechanisms and kinetics of the molecule.

Beta 2-microglobulin (beta 2-m) accumulation represents a possible complication of long term dialysis. It is therefore important to evaluate the capacity of removal of this molecule from the patient by different dialysis membranes. The present study is aimed at evaluating the mechanisms involved in beta 2-m removal by three different synthetic membranes: a) highly asymmetric hydrophobic polysulfone (Biosulfane, NMC), b) moderately asymmetric and hydrophobic polysulfone (PS600, Fresenius), c) Polyacylonitrile (AN69HF, Hospal). The adsorption capacity and sieving coefficients of the three membranes for native and labeled beta 2-m were studied in vitro utilizing human blood. The amount adsorbed by the membrane was measured by the elution of the molecule obtained with a detergent solution. Clearances, total removal and membrane adsorption were studied in six patients treated in a randomized sequence with the three membranes. For this purpose, plasma and dialysate measurements as well as total collection of spent dialysate and beta 2-m elution from the used dialyzers were carried out. Ex novo generation of beta 2-m did not take place during in vitro circulation. The molecule was removed by the studied membranes both by filtration and adsorption. The Biosulfane membrane removed beta 2-m mostly by adsorption while the PS600 membrane removed beta 2-m almost entirely by filtration. Intermediate behaviour was shown by AN69 membrane. Similar quantities of beta 2-m were removed from the patients with the three membranes. Total removal could only be precisely measured by adding the quantity of beta 2-m eluted from the membrane to the amount recovered in the spent dialysate. Out of total removal, adsorption was more than 90% with Biosulfane, while only 5% with the PS600. These findings contribute to the understanding of the discrepancy found between the clearance measured from the plasma side and that measured from the dialysate side. In conclusion, clearance and sieving measurements for beta 2-m cannot be correctly performed unless the capacity of adsorption of the membrane is taken into account.

Acrylic Resins↗