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F Nardi

Publications and source records attributed to F Nardi.

At least 55 records · Page 3Linked to original sources
PubMed1997

Local interactions of aromatic residues in short peptides in aqueous solution: a combined database and energetic analysis.

Although short peptides are usually structurally disordered in aqueous solution, particular peptide sequences display local structure. We performed database and conformational searches, along with molecular dynamics simulations, to study two local interactions detected by 1H-NMR in tetrapeptides excised from bovine pancreatic trypsin inhibitor: aromatic-(i+2)amide and (i-1)cisproline-aromatic. For both types of interaction, at least two major and distinct peptide conformations are identified in the folded state. The aromatic-(i+2)amide interaction can have parallel and perpendicular arrangements of the N-H bond and the aromatic ring. The (i-1)cisproline-aromatic interaction can have close packing of the aromatic ring to the (i-2)C alpha H or the (i-1)C gamma H but not both simultaneously. Although these local aromatic interactions are weak, they may influence folding and binding properties. The combination of search and simulation techniques provides a useful route towards obtaining an atomic-detail description of peptides exhibiting these interactions.

Amides↗
PubMed1997

Utility of HBME-1 immunostaining in serous effusions.

HBME-1 is an anti-mesothelial cell monoclonal antibody derived from human mesothelioma cells. We investigated 227 body cavity effusions to test its utility in differentiating mesothelioma from adenocarcinoma. HBME-1 outlined cell membranes in non-neoplastic mesothelial cells. Thick surface staining was observed on all mesotheliomas. HBME-1 reactivity was also detected in 24% of metastatic carcinomatous effusions. Most ovarian carcinomas (83%) reacted with this antibody, showing surface staining. Cytoplasmic HBME-1 immunoreactivity was observed in a small proportion of non-ovarian adenocarcinomas (14%). Despite its limited specificity, HBME-1 might be added to the battery of other markers of epithelial and/or mesothelial differentiation to be used in cases of suspected mesothelioma. Evaluation of suspicious cells should include careful study of the pattern of immunostaining.

Adenocarcinoma↗
PubMed1996

Concomitant malignant mesothelioma of the pleura, peritoneum, and tunica vaginalis testis.

We describe the cytohistological, immunohistochemical and ultrastructural findings in a 55-yr-old-man with history of asbestos exposure and diffuse malignant mesothelioma (DMM) of the pleura, peritoneum, and tunica vaginalis presenting with chest pain and scrotal swelling. Pleural fine-needle aspiration (FNA) revealed mesenchymal elements and spindle-shaped epithelial-like cells, while biopsy showed pure sarcomatous tumor invading lung parenchymal. In both samples tumor cells coexpressed cytokeratin and vimentin. Peritoneal and hydrocele effusions contained aggregates of malignant mesothelial cells. Electron microscopy showed intermediate filaments, rare desmosomes and sparse microvilli. Morphological findings were consistent with a DMM, with a biphasic pattern in the pleura and an epithelial one in the peritoneum and tunica vaginalis. Although the possibility of a multicentric origin cannot be ruled out, clinical chronologic sequence suggests that the pleura was the primary involved site, followed by spread to peritoneum and tunica vaginalis.

Asbestos↗
PubMed1996

Morphological changes in a hyperfunctioning thyroid adenoma after percutaneous ethanol injection: histological, enzymatic and sub-microscopical alterations.

Ultrasound-guided ethanol injection (PEI) is an effective treatment of autonomously functioning thyroid nodules (AFTN) but little is known about the tissue lesions induced by alcohol. We report morphological changes of an AFTN which was removed after successful PEI treatment. At histological evaluation, the adenoma showed multiple areas of coagulative necrosis with eosinophilic ghost follicles, hemorrhages, small vessel thrombosis and a wedge-shaped hemorrhagic infarction. The peripheral adenomatous tissue and the surrounding thyroid parenchyma were free of regressive changes and/or lympho-monocytic inflammatory reactions. Enzyme histochemistry confirmed the hyperfunctioning character of the lesion and showed reduction of succinic dehydrogenase and cytochrome-c-oxydase activity in the viable tissue surrounding the central necrotic areas. By electron microscopy, the hyperfunctioning follicular epithelium showed submicroscopical alterations of the adenomatous cells surrounding the areas of coagulative necrosis. These results suggest that control of hyperthyroidism, after PEI, is due to: a) directly induced, irreversible damage (coagulative necrosis and vascular thrombosis with hemorrhagic infarction) in the central areas of the lesion; b) potentially reversible damage (reduction of intracellular enzyme activity and ultrastructural changes) in the peripheral areas.

Acid Phosphatase↗
PubMed1995

Utility of cytokeratin 20 in identifying the origin of metastatic carcinomas in effusions.

Using a commercially available monoclonal antibody (Ks20.1) and the avidin-biotin peroxidase method on cytospins and cell blocks, we analyzed cytokeratin (CK) 20 expression in 169 serous effusions. Cytoplasmic staining was observed in 44/151 malignant fluids. Colon, gastric, and pancreatic adenocarcinomas and mucinous ovarian tumors were most frequently positive. Single cases of transitional-cell and squamous cell carcinomas were reactive as well. Lung and breast cancers were mostly negative. Nonmucinous ovarian tumors were invariably unlabeled as were mesotheliomas and normal mesothelial cells. The study shows that CK 20 is valuable in distinguishing tumor cell origin in effusions. In particular, it identifies a set of carcinomas with the majority arising from the gastrointestinal tract, and represents a highly characteristic marker for colorectal cancer.

Adolescent↗
PubMed1995

The diagnostic value of thrombomodulin immunolocalization in serous effusions.

OBJECTIVE: To test the value of an antithrombomodulin monoclonal antibody as a diagnostic tool in detecting mesothelial cells and in differentiating mesothelioma from other malignant effusions. DESIGN: Thrombomodulin is a thrombin receptor that is distributed on surfaces where an anticoagulant activity is expected, including mesothelium. Antigen expression was studied by immunocytochemistry in 226 peritoneal and pleural exudates. RESULTS: The antigen was found in 33 of 33 mesotheliomas, 35 of 35 reactive effusions, 57 of 145 carcinomatous fluids, and in one case of angiosarcoma among seven metastatic nonepithelial tumors. Three distinct staining patterns were demonstrated: (1) thin cell membranes in benign mesothelial cells; (2) thick cell membranes in mesotheliomas; and (3) cytoplasm in carcinomas. All squamous cell carcinomas had demonstrable thrombomodulin, suggesting that antigen expression likely correlates with squamous differentiation. CONCLUSIONS: Thrombomodulin is of diagnostic utility in distinguishing mesothelioma from adenocarcinoma, provided the characteristic "thick membrane" pattern is present, but it should be used in panels with other markers of mesothelial and/or epithelial differentiation.

Adenocarcinoma↗
PubMed1994

Cytodiagnosis of a primary non-Hodgkin's lymphoma of bone.

We report fine-needle aspiration cytology and histologic findings of a primary non-Hodgkin's lymphoma of bone involving the rib and iliac bones. Smears contained abnormal lymphoid cells and abundant lymphoglandular bodies, suggesting a malignant lymphoproliferative disease. However, histologic sections showed nests of tumor cells with extensive cytoplasmic clearing surrounded by sclerosis, thus mimicking a carcinoma. Clinical data, radiographic findings, and cytohistological correlation led to a final diagnosis of primary non-Hodgkin's lymphoma of the bone, confirmed by immunopositive staining for leukocyte common antigen CD45 and B-cell associated antigen CD20. It is concluded that finding numerous lymphoglandular bodies in bone tumor specimens allows an accurate diagnosis of lymphoid tissue. The rarity of bone lymphoma and the misleading histologic features can cause considerable difficulty in diagnosing this entity. The importance of identifying lymphoglandular bodies and the appropriate use of immunochemistry are emphasized.

Aged↗
PubMed1994

PCR amplification and analysis of ras oncogenes from thyroid cytologic smears.

Fine needle aspiration (FNA) cytology represents a reliable diagnostic procedure for preoperative identification of thyroid carcinoma. For improving its diagnostic accuracy, a technique that allows the analysis of cancer-related gene abnormalities on thyroid FNA smears has been developed. Cells were collected by scraping from thyroid smears, DNA-extracted and ras proto-oncogene sequences amplified by the polymerase chain reaction (PCR). Preliminary destaining of cytologic smears was essential for efficient PCR amplification. Twelve thyroid FNA cytologic smears, characterized by the indeterminate pattern of follicular neoplasia, were analysed for the presence of ras mutations known to confer an oncogenic potential. The same nucleotide substitution at codon 12 of the H-ras proto-oncogene was detected in two different thyroid nodules among six cases that, at final histology, were identified as follicular carcinomas. No ras mutations were observed in the remaining six cases that were diagnosed as follicular adenoma at histologic examination. Molecular analysis of FNA smears may provide additional information on the nature of the lesion underlying thyroid neoplasia, thus improving diagnostic accuracy of conventional FNA cytology.

Adolescent↗
PubMed1993

Sialadenosis of the parotid gland: report of four cases diagnosed by fine-needle aspiration cytology.

Four patients presented with a history of recurrent bilateral swellings of parotid glands. Fine-needle aspiration (FNA) specimens showed highly cellular smears containing clusters of enlarged acini and numerous naked nuclei. A diagnosis consistent with sialadenosis was made considering the distinct morphologic appearance: micrometric measurements in all cases, in addition to histology and electron microscopy in two cases confirmed this hypothesis. A review of clinical histories revealed hormonal, nutritional and neurogenic disorders, which are known to be associated with sialadenosis. In the work-up of salivary gland swellings, it is important to recognize cytologically this underestimated entity, which does not necessarily require surgical treatment.

Adult↗
PubMed1993

C-erbB-2 oncoprotein immunostaining in serous effusions.

The product of c-erbB-2 gene is detected in a proportion of carcinomas from various sites and is generally associated with a high degree of malignancy. A series of 58 effusions containing malignant cells and 16 cytologically negative serous effusions was assessed by immunocytochemical methods for c-erbB-2 expression using the monoclonal antibody NCL-B11, which recognizes the internal domain of the c-erbB-2 oncoprotein. Both alcohol-fixed smears and cell blocks from formalin-fixed specimens were used. A crisp, clear cut membrane-associated positive staining was evident in 51% (30/58) malignant effusions and was restricted to metastatic adenocarcinomas. Breast and ovarian cancers showed the highest incidence of positivity. Mesotheliomas as well as non-neoplastic effusions were consistently negative. Paraffin blocks from formalin-fixed cells displayed a weak immunoreactivity when compared with their alcohol-fixed counterparts. The study shows that the c-erbB-2 oncoprotein can be easily identified in standard cytological smears: it can be of assistance in differentiating adenocarcinomas from mesotheliomas, and in selected cases it can provide a further prognostic indicator, replacing tissue immunohistochemistry.

Adenocarcinoma↗
PubMed1993

Percutaneous ultrasound-guided ethanol injection: a new treatment of toxic autonomously functioning thyroid nodules?

Twenty autonomously functioning thyroid nodules were treated with ultrasound-guided percutaneous ethanol injection (PEI) and followed for 12 months. PEI was performed on symptomatic and biochemically proven thyrotoxic patients by injecting 2.0-4.0 mL sterile ethanol and was repeated 3-8 times, depending on nodule size. Serum thyroglobulin increased immediately after PEI, peaked at 6-10 h, and declined thereafter. Free T4 progressed slowly during the first 24 h. Free T3 showed a delayed and not significant increase. By the end of the treatment (4 weeks), PEI had produced clinical improvement and hormonal normalization. Three months later, serum TSH was detectable and responsive to TRH in 17 of the 20 patients. All nodules had a significant shrinkage at ultrasound evaluation. The previous hot thyroid areas manifested hypofunction at technetium-99 m-pertechnetate scintiscan, and the surrounding parenchyma returned to normal function in all but the 3 cases with still suppressed TSH. The histological features of a nodule that had been operated upon and the fine needle aspiration biopsy patterns obtained after PEI showed coagulative necrosis, with scanty follicles, some fibroblasts, but no lymphocytic infiltration. The procedure was generally well tolerated, but in 1 case it induced temporary dysphonia, and in another patient, it caused a transient exacerbation of thyrotoxicosis.

Adult↗
PubMed1993

[Long-term results of echographically guided percutaneous ethanol injection in the treatment of the autonomous thyroid nodule].

Ultrasound-guided percutaneous ethanol injection (PEI) was performed as a therapeutic procedure on twenty-four patients affected by toxic autonomously functioning thyroid nodules (AFTN). After treatment patients were followed up for a mean period of 12 months. PEI induced persistent and complete (clinical and hormonal) disease control in 19/23 cases (82.6%) that completed the procedure, normalization of serum FT4 and FT3 associated with a still suppressed TSH in 2/23 cases (8.6%) and failed to control hyperthyroidism in 2/23 cases (8.6%). After PEI all AFTN became smaller at clinical and US examination with a 60% mean volume decrease. Nodule shrinkage was related to cytological and histological findings of well circumscribed coagulative necrosis, granulomatous inflammation and progressive fibrosis. PEI induced two cases of temporary complications: 1 case of acute worsening of thyrotoxicosis and 1 case of self-resolving vocal cord paresis. No increase of serum autoantibodies (TgAb, TPOAb, TRAb) was detected during the follow-up period.

Adult↗
PubMed1991

A randomized trial of ultrasound-guided anterior subcostal liver biopsy versus the conventional Menghini technique.

An ultrasound-guided double pass biopsy technique using a large bore cutting needle via an anterior subcostal route (USAB) is described. The diagnostic adequacy of this biopsy procedure was evaluated in comparison with the traditional Menghini technique in 200 cases of suspected chronic liver disease randomly assigned to the two different procedures. Retrieval rate was better in the USAB group. The sample length was less than 15 mm in four cases in the USAB group and in 19 cases in the Menghini group. In three cases in the USAB group the second pass modified the diagnosis of the first specimen from chronic active hepatitis to active cirrhosis. In order to evaluate the safety and discomfort of the two procedures 340 patients assigned to the different techniques had liver ultrasound scans 6 and 24 h following percutaneous biopsy. USAB was associated with a reduced frequency of complications (one out of 170 patients vs. seven out of 170 patients who had the intercostal Menghini procedure). In our study, USAB seems to offer better sampling and size of individual samples, together with reduced frequency of major and minor complications.

Biopsy↗
PubMed1991

[Echo-guided needle biopsy of the thyroid. An assessment of 52 thyroid neoplasms found in 1042 consecutive patients].

The authors report on a series of 1,043 fine-needle biopsies of the thyroid performed under US guidance; the patients had been selected for thyroid pathologic conditions. Fifty-two neoplasms were observed (46 papillary carcinomas, 1 medullary carcinoma, 2 follicular carcinomas, and 3 metastases), which had been detected by cytology and confirmed by histology or autopsy. The authors focus on 46 cases of papillary carcinoma: their US features were studied which, through a correlation of variables, allow a quick and "safe" recognition of the type of carcinoma (papillary carcinomas account for nearly 60% of thyroid neoplasms). Tumor echogenicity and outline, and the presence/absence of calcifications were evaluated: in most cases, papillary carcinomas presented as focal lesions (alone or associated with other goiter lesions), with irregular and blurred outline, no hypo/anechoic halo and, in about 1/3 of the cases, with calcifications and colliquative areas. In 17% of papillary neoplasms, metastases to loco-regional nodes were observable at US; in 3 cases the carcinoma did involve a loco-regional node but there were no US signs suggestive of it. The incidence of neoplasms on the total of fine-needle biopsies is 4.9%, while in a previous series of 3,038 fine-needle biopsies, without US guidance, on clinically detectable lesions, the figure was about 2%.

Adenocarcinoma↗