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Biomedical subjects

D Pacchioni

Publications and source records attributed to D Pacchioni.

At least 37 records · Page 2Linked to original sources

Albumin gene expression in liver tumors: diagnostic interest in fine needle aspiration biopsies.

Albumin is a specific product of normal and transformed hepatocytes, but unfortunately its immunohistochemical demonstration proves unreliable because of diffusion artifacts. An in situ hybridization procedure to reveal albumin mRNA was applied to fine needle aspiration specimens of liver nodes with the aim of testing the usefulness of this marker in the cytological diagnosis of hepatocellular carcinomas (HCC). A 51-base pair oligonucleotide probe was labeled with digoxigenin and used on paraffin sections of alcohol-fixed cell blocks. A series of 97 cases originally interpreted, on the basis of cytology alone, as "hepatocellular carcinoma" (62 cases), as "carcinoma cells, not otherwise specified" (15 cases), as "adeno-carcinoma" (16 cases), and as "non-epithelial neoplastic cells" (4 cases), was studied. In all cases, clinical and follow-up information was obtained; a diagnosis of HCC was reached with certainty in 44 cases and suspected in 22. Thirty-one other cases were proven to be bile duct adenocarcinomas or metastatic tumors. Taking into account proven cases only, albumin mRNA was found in 42/44 HCC and in none of the control cases (sensitivity, 95.5%; specificity, 100%). Of 22 cytologically suspected HCC, albumin mRNA was positive in 19 cases. Also, high grade pleomorphic HCCs expressed albumin gene, and this finding is of value in the differential diagnosis with liver metastases of anaplastic tumors from lung, adrenal, pancreas, etc. The diagnosis of HCC on a cytological basis is becoming increasingly important because most cases are unresectable and have to be included in different therapeutic protocols.(ABSTRACT TRUNCATED AT 250 WORDS)

Albumins↗

Expression of estrogen receptor mRNA in tumorous and non-tumorous liver tissue as detected by in situ hybridization.

Estrogen receptor mRNA was detected by a non-radioactive in situ hybridization assay in tumor and non-neoplastic liver tissues. A synthetic oligonucleotide complementary to the human estrogen receptor mRNA was 3'-labeled with digoxigenin-deoxyuridine triphosphate (dUTP). Hybrids were revealed by an alkaline phosphatase-conjugated anti-digoxigenin antibody. Fourteen primary hepatocellular carcinoma tissues (and one metastatic) were obtained at surgery from 15 patients. The corresponding non-neoplastic liver tissues were available in 13 cases. The estrogen receptor mRNA was detected in 11 tumorous and 7 non-tumorous liver specimens. The staining was cytoplasmic and involved the majority of transformed hepatocytes, whereas a less widespread and weaker signal was found in normal hepatocytes. Within non-neoplastic tissue, bile duct epithelial cells could also be occasionally stained, whereas other cell types, such as vasal endothelial cells, were negative. Appropriate controls established the specificity of the reaction. Detection of the estrogen receptor protein by immunohistochemistry in these same specimens was invariably negative. This in situ hybridization assay can therefore be used as a complementary tool to evaluate the estrogen receptor expression within liver cancer.

Adolescent↗

Immunophenotypic properties and estrogen dependency of budding cell structures in the developing mouse mammary gland.

The initial phase of growth of the parenchymal component of the mouse mammary gland is ductal clongation, which is mainly accomplished by proliferating cells in a specialized structure termed end bud. End buds are composed of multiple layers of epithelial cells (so called body cells) which are capped by a single layer of morphologically unique cells termed cap cells. We sought to examine the interrelationship between cap cells and other epithelial cell subclasses using a variety of antibodies to different keratin proteins and also antibodies to vimentin, actin and collagen IV. An extensive immunohistochemical characterization of the epithelial components of the developing and differentiating mammary gland demonstrated that cap cells were devoid of any immunohistochemically-detectable keratins but were positive for collagen IV. In contrast, the majority of cells in the end bud along with the luminal epithelial and myoepithelial cells were keratin positive. The body cells of the end bud were the only cells which were positive for antibody to keratin 6, a keratin which previously has been reported to be expressed in proliferating mammary epithelial cells. In addition, estrogen receptor was localized only to epithelial cells of ducts, alvcoli and body cells of end buds, but not to cap cells or myoepithelial cells. We interpret these results to suggest that cap cells are not totpotent stem cells but rather cells specialized in paving the way for ductal elongation as well as serving as precursors to myoepithelial cells.

Actins↗

Detection of intrahepatic replication of hepatitis C virus RNA by in situ hybridization and comparison with histopathology.

A nonisotopic in situ hybridization (NISH) assay was used to detect hepatitis C virus (HCV) RNA. A synthetic oligonucleotide complementary to bases 252-301 of the highly conserved 5' noncoding region of the HCV genome was end-labeled by terminal deoxynucleotidyltransferase using digoxigenin-conjugated dUTP. The hybridized oligomer was revealed by an immunohistochemical reaction after incubation with an alkaline phosphatase-conjugated anti-digoxigenin antibody and subsequent amplification with a complex of alkaline phosphatase and anti-alkaline phosphatase antibodies. The intracellular distribution of HCV RNA was monitored in the livers of two chimpanzees experimentally infected with the H strain of HCV and compared with the serum alanine aminotransferase activity, serum HCV RNA, and liver histopathology. Most cells were stained in the cytoplasm as early as 2 days after inoculation, 1 and 2 days, respectively, before the appearance of viral RNA in the serum. The time course of HCV RNA replication was correlated with increases in serum alanine aminotransferase. However, neither one paralleled the appearance of liver cell necrosis nor showed any correlation with the inflammatory response. The NISH signal was not found in liver biopsy specimens taken from these two animals before inoculation with HCV, from chimpanzees with acute hepatitis type A, B, or delta, or from two animals never experimentally infected with any hepatitis agent; moreover, it disappeared when the positive specimens were predigested with RNase and it was not observed after hybridization of positive controls with a labeled oligomer unrelated to HCV RNA. Thus, detection of liver HCV RNA by NISH is a sensitive and specific method for studying HCV replication at the cellular level. Intracellular replication of HCV did not appear to be associated with histopathologic changes in the liver, although the correlation with increases of liver enzyme activity in the serum suggested possible damage to the liver cell membrane.

Alanine Transaminase↗

Immunohistochemical detection of estrogen and progesterone receptors in the normal urinary bladder and in pseudomembranous trigonitis.

According to recent studies showing the presence of estrogens receptors (ERs) in the human female lower urinary tract, we performed ER and progesterone receptor (PR) assays in fresh frozen and paraffin embedded biopsies taken from the urinary bladder. Fourteen females undergoing endoscopy during staging for gynecological cancer (endometrium, cervix, ovary) and 15 women complaining of recurrent abacterial cystitis (pseudomembranous trigonitis) were enrolled in the study as Group 1 and Group 2, respectively. After informed consent, they were submitted to cystoscopy, during which two biopsies were taken: one on the trigonum and the other on the bladder lateral wall. ERs were identified in both groups only in the trigonum (7/14 patients in Group 1 and 8/15 in Group 2), whereas the bladder lateral wall always stained negative. PRs were found at both sites in both groups (11/14 cases on the trigonum and 7/14 on the bladder lateral wall in Group 1; 11/15 and 2/15 respectively in Group 2). Morphological localization of PRs showed intense omogeneous staining in the nuclei of the stromal fibroblasts too. A clear correspondence between the presence of steroid receptors at the squamous metaplasia of the trigonum was observed. These data are discussed speculating about a possible endocrine pathogenesis of pseudomembranous trigonitis.

Adult↗

Detection of hepatitis delta virus RNA by a nonradioactive in situ hybridization procedure.

A digoxigenin-tailed, synthetic oligodeoxynucleotide was used to detect genomic hepatitis delta virus (HDV) RNA in formalin-fixed, paraffin-embedded liver sections by a nonisotopic in situ hybridization (NISH) procedure. Twenty-three liver samples from chronically HDV-infected patients were studied. Eight liver specimens from humans and chimpanzees without markers of active HDV infection served as negative controls. In three samples, the NISH findings were compared with characteristic nuclear features and with the distribution of the HDV encoded antigen, HDAg, as detected by direct immunofluorescence. All samples from HDV-infected patients were positive for HDV RNA by NISH. The viral genome was exclusively observed within the hepatocytic nuclei. No enzymatic reaction was detected after hybridization with the negative controls. "Sanded" nuclei, a cytopathologic change associated with HDV infection, were HDV RNA-positive, but only a small percentage of infected cells showed that feature. Hepatocytes containing the HDV RNA were sometimes binucleated or exhibited giant nuclei. When HDAg and HDV RNA were sequentially detected within the same sections, the localization of the viral antigen almost completely overlapped with the expression of the HDV transcripts, and vice versa. In conclusion, detection of intrahepatic HDV RNA by NISH is a rapid, sensitive, and specific technique that is easily applicable to routine histopathology and allows correlation of HDV with the morphology of hepatocyte nuclei.

Antigens, Viral↗

Detection of cytomegalovirus by in situ hybridization using a digoxigenin-tailed oligonucleotide.

A non-isotopic in situ hybridization procedure was used to detect cytomegalovirus (CMV) sequences within routinely fixed tissue. A digoxigenin-tailed oligonucleotide was hybridized to sections of specimens obtained at autopsy from 2 patients with CMV infection. Hybrids were revealed by an alkaline phosphatase-conjugated anti-digoxigenin antibody. Serial sections were also assayed for the presence of CMV by in situ hybridization with a biotin-labelled cDNA probe and by immunohistochemistry and routinely stained for morphological evaluation. Results show that the two in situ hybridization procedures are equally sensitive but superior to the immunohistochemical detection of the viral antigen. Most cells positive for CMV DNA had the cytopathological features characteristic of CMV infection. A minor population of infected cells lacking morphological changes was also found. We recommend the routine application of the oligonucleotide-based assay because it is specific, easy and less expensive than other similar procedures.

Alkaline Phosphatase↗

In situ hybridization in viral hepatitis.

In situ hybridization (ISH) is a sensitive and specific technique for detecting nucleic acids in intact cells. Visualization of the target sequences by autoradiography or immunohistochemistry allows their precise subcellular localization and quantitation. The application of ISH techniques has contributed to the understanding of the complex replicative cycle of hepatitis B virus. More recently, hepatitis delta and C virus replication has also been studied by this technique. ISH-based assays have finally been used to follow the replication of cytomegalovirus within the transplanted liver. Although ISH is a powerful tool for the molecular biologist, its clinical significance in the diagnosis and prognosis of human hepatitis virus infections has yet to be fully evaluated.

Hepacivirus↗

Staining reaction for beta-galactosidase in immunocytochemistry and in situ hybridization.

beta-galactosidase, revealed by an indigo blue reaction product, represents a valid tracer in immunohistochemistry. Observations on the instability of the indigo precipitate led us to investigate this phenomenon. We conclude that avoiding of xylene, and mounting of the preparates in Histoclear (a xylene substitute) and Canada balsam (instead of synthetic resin mountants) yields a sharp and stable indigo precipitate. In addition, we propose a sensitive alternative staining procedure for beta-galactosidase, based on TNBT reduction and precipitation. These reactions can be used both in immunohistochemistry and in in situ hybridization.

Galactosidases↗

Hepatitis delta virus heterogeneity: a study by immunofluorescence.

Hepatitis delta virus (HDV)-RNA shows a microheterogeneity at nucleotide 1015 resulting in the production of two co-terminal forms of the HDV-associated antigen (HDAg), referred to as p24 and p27. In vitro experiments have shown that p24 is localized within the nucleolus, while p27 expression is probably confined to the nucleoplasm. The sequential appearance of these two proteins may play a role in the HDV-induced cell damage. We have examined 12 formalin-fixed human liver biopsies taken at different phases of the natural course of HDV infection. Specimens were assayed for HDAg by direct immunofluorescence with a human IgG reactive towards both p24 and p27. Positive cells were then examined for cytopathological features after hematoxylin/eosin staining. All biopsies contained intranuclear HDAg. However, three different patterns of fluorescence were seen: (1) nucleolar with weak nucleoplasmic; (2) homogeneous nucleoplasmic with negative nucleolus; (3) intense fluorescence diffuse to the whole nucleus. Pattern 1 was found in 15-50% of positive nuclei of all samples, irrespective of the phase of infection, while the remaining positive nuclei mostly showed another pattern (2) of fluorescence. Neither pattern was associated with cytoplasmic eosinophilia. Degenerated hepatocytes, when infected (5%), showed pattern 3 of HDAg fluorescence but were mostly negative for HDV. Therefore, the intranuclear distribution of HDAg, as assayed in vivo, does not seem to correlate with peculiar phases of HDV infection. Different phases of the viral life style, instead, are asynchronously represented within each liver sample.(ABSTRACT TRUNCATED AT 250 WORDS)

Antigens, Viral↗

Peri and intratumoral macrophage infiltration in laryngeal carcinoma. An immunohistochemical study.

The role of macrophages infiltrating tumor tissue is still poorly explained; the data available are sparse and, to the best of our knowledge, there is no study relating the characteristics of such infiltration to tumor evolution and final outcome. We decided to investigate the spatial relationships between macrophages and neoplastic tissue and their possible prognostic significance on a series of laryngeal carcinomas (98 patients) all of which were operated in our Department and had a follow-up of at least 3 years. In order to identify the macrophage infiltration, formaline-fixed/paraffin-mounted specimens of the tumor were treated with MoAb HAM56. No statistically significant relationship could be established between the degree of macrophage infiltration and the clinical outcome (recurrence), even when the N status was taken into account (N- vs. N+). However, a clear trend was observed when the analysis was confined to grade 3 cases, where the presence of a significant number of macrophages was correlated with a higher probability of recurrence.

Cell Movement↗

Detection of estrogen receptors in the trigonum and urinary bladder with an immunohistochemical technique.

In order to detect estrogen receptors (ER) in the female bladder, 5 premenopausal and 10 postmenopausal women affected by gynecological diseases were submitted to cystoscopy, during which both the trigonum and the bladder lateral wall were biopsied. A new, simple, cost-effective immunohistochemical technique was employed to stain the estrogen specific binding sites. ER were found in the trigonum of 3 premenopausal and 4 postmenopausal subjects, while the bladder lateral wall was always ER-negative. A comparison with previously used ER detection methods and a discussion of further hypothetical applications of the immunohistochemical technique in the study of the lower female urogenital tract are reported.

Adult↗

Gastrointestinal cancer-associated antigen (GICA) in oral carcinoma.

Gastrointestinal cancer-associated antigen (GICA) is detected by means of a monoclonal antibody in the serum and pathologic tissues of patients with gastrointestinal tumors. This article compares serum and salivary GICA and carcinoembryonic antigen (CEA) levels in 19 healthy control subjects, 17 patients with benign oral cavity lesions, and 11 patients with squamous cell carcinoma of the oral cavity. Serum CEA levels were similar in all three groups, whereas salivary CEA levels were higher in patients with squamous cell carcinoma than in the control subjects (p less than 0.001) and the patients with benign lesions (p less than 0.025). Serum GICA levels gave the opposite result and were significantly lower in squamous cell cancer when compared with control subjects (p less than 0.0001) and patients with benign lesions (p less than 0.02). Values of GICA in saliva of patients with oral cancer were also lower than in the control subjects (p less than 0.02). The possible significance of this difference between the two antigens is discussed.

Adult↗