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A Cardesa

Publications and source records attributed to A Cardesa.

At least 19 recordsLinked to original sources
PubMed1992

The carcinogenic effect of 2,2-dioxopropylnitrosamine on the renal pelvic epithelium of Sprague-Dawley rats, after chronic subcutaneous injections.

The carcinogenicity of 2,2-dioxopropylnitrosamine on the urinary tract was investigated in three experimental groups of Sprague-Dawley rats (15 males, 15 females/group) by weekly subcutaneous administration for the life of the carcinogen at dose levels 1/5, 1/10 and 1/20 of the LD50, and compared with that in a similar group of untreated controls. It resulted in the induction of urinary tract tumours in 42 out of 79 effective animals (53%). Of these animals, 38 developed tumours within the renal pelvis. In the high-dose group, females had a 100% incidence of renal pelvic tumours, and males 73%. In all experimental groups, renal pelvic tumours were more frequent than ureteral and vesical ones. Histologically, the tumours were transitional cell papillomas and carcinomas, except for one squamous carcinoma. Out of 66 tumours, 42 (64%) were low-grade. High-grade tumours arose mainly in the renal pelvis of animals belonging to the highest-dose group. This experiment offers a useful model for the study of mechanisms involved in renal pelvic carcinogenesis.

Animals↗
PubMed1992

Pathology of bone marrow transplantation.

For evaluating the therapeutic approaches in the follow-up and complications of patients treated with bone marrow transplantation (BMT), the histopathology is important on many occasions. The authors describe the different morphological changes that have an important role for treatment of these patients, classified according to their target organs of localization: skin, digestive tract, liver, and bone marrow. Graft-versus-host disease (GVHD) mainly affects the skin, gastrointestinal tract, and liver, and is sometimes difficult to differentiate from radiochemotherapy or infectious diseases. In the liver, the most frequent complications are GVHD, veno-occlusive disease, and infections. In the bone marrow, it is most important to evaluate the elimination of hemopathy and the reconstitution of normal hematopoiesis.

Bone Marrow Transplantation↗
PubMed1992

Acquired renal cystic disease in HD: a study of 82 nephrectomies in young patients.

In order to study the development of acquired renal cystic disease (ARCD) and its potential complications, we studied, macro- and microscopically, 82 surgical specimens of nephrectomy carried out on young patients with chronic renal failure previous to renal transplantation. Statistical correlation of pathological findings with age, sex and time on hemodialysis (HD) have been done. There were 72 cases of ARCD (87.8%). It was statistically correlated with male sex (p less than 0.02) and prolonged time on HD (p less than 0.001) as has been previously reported. Hyperplasia of the cystic epithelium was found in 42 cases (52%), with 18 (22%) showing marked papillary proliferation. Also, there were 22 cases (27%) with renal adenomas. This incidence of hyperplastic and neoplastic proliferations, more than would be common in such a young population (males: 33.5 +/- 9.3 years; females: 35.4 +/- 11.7 years), suggests the potential of patients affected by ARCD to develop neoplasms. Thus, we consider that these patients must be checked periodically to detect possible malignant neoplasms.

Adenoma↗
PubMed1991

Loss of heterozygosity of p53 gene and p53 protein expression in human colorectal carcinomas.

The p53 gene is a tumor suppressor gene located on chromosome 17p. Deletions of this chromosome and point mutations of p53 have been implicated in the development of colonic neoplasms. We have analyzed the loss of heterozygosity of the human p53 tumor suppressor gene in 40 cases of colorectal carcinoma using two restriction fragment length polymorphisms detected by BglII and AccII restriction enzymes. p53 gene product expression was studied immunohistochemically in 64 colorectal carcinomas, 18 adenomas, and 40 normal colonic mucosae using an anti-human p53 monoclonal antibody (Pab 1801) and the avidin-biotin-peroxidase complex technique. Twelve of the 40 patients (30%) were polymorphic for the p53 gene. In ten of these informative patients (83%), the tumor samples showed the loss of one allele when compared with normal colorectal samples of the same patient. One of the homozygous patients showed a loss of both p53 alleles. p53 immunostaining was observed in 43 of 64 carcinomas (67%) but only in two adenomas (11%). These two positive adenomas showed areas of carcinoma in situ. The normal mucosa was always negative. No relation could be found between p53 immunostaining and the degree of differentiation, the extension of the tumor, or the Ki-67 proliferative index. Mucinous carcinomas and right-side carcinomas were less p53 immunoreactive (25% and 52%, respectively) than the usual adenocarcinomas (73%) and distal tumors (72%). These findings suggest that p53 may be a target of chromosome 17 deletions and that this gene may play a role in the malignant transformation of adenomas. BglII and AccII restriction fragment length polymorphism analysis of the p53 gene may be a useful and direct technique to detect allelic loss of this gene in tumors.

Adenocarcinoma↗
PubMed1991

Adult type of leukodystrophy. Krabbe's disease?

A 24-year-old man developed progressive dementia in seven years. The patient suffered a severe bronchopneumonia and eventually died few days later. Brain coronal sections showed a soft gray-brownish discoloration of white matter of centrum ovale but the subcortical arcuate fibers and the interne capsule were preserved. Microscopically, the white matter showed marked loss of myelin and oligodendrocytes, abundant hypertrophic astrocytes and numerous "globoid cells". The latter showed strong positivity in immunostains for a mouse monoclonal antigalactocerebroside antibody. The presence of these cells in the brain white matter might be the morphological basis to classify the present case as one of Krabbe's Leukodystrophy.

Adult↗
PubMed1991

Human chorionic gonadotropin in esophageal carcinomas. An immunohistochemical study.

We have examined immunohistochemically the presence of human chorionic gonadotrophin (hCG) in 29 esophageal carcinomas: 24 squamous cell carcinomas, 2 adenocarcinomas, 2 adenoid cystic carcinomas and 1 adenosquamous carcinoma. In hCG-positive tumors, the presence of human placental lactogen (hPL) and pregnancy-specific beta-1 glycoprotein (SP-1) was also assessed. HCG immunoreactive cells were found in 5 squamous cell carcinomas (21%) and in none of 5 non-squamous cell tumors. The hCG positive cells were found in the most infiltrating areas of the tumors where poorly differentiated and pleomorphic cells predominated. The positive tumors were 4 poorly differentiated (31%) and one moderately differentiated carcinoma (12%). Four out of 10 cases (40%) with lymph node metastases had hCG in the primary tumor, whereas only one out of 11 cases (9%) without metastases was hCG positive. HPL and SP-1 were found in two cases. These placental proteins were detected in similar areas than hCG but the number of hPL and SP-1 immunoreactive cells was lower than hCG positive cells. SP-1 was also seen in areas of squamous cell differentiation negative for hCG. None of these two cases showed trophoblastic differentiation.

Adenocarcinoma↗
PubMed1991

Adenosquamous carcinoma of the esophagus. A case report.

A case of adenosquamous carcinoma of the esophagus is presented. This carcinoma is a typical neoplasm of the upper aerodigestive tract almost exclusively originating in squamous epithelium in continuity with minor salivary glands. It is a very rare tumor in the esophagus, and is often diagnosed as mucoepidermoid carcinoma. The differential diagnosis between them is important due to the better prognosis of the last entity. The histology and electron microscopy is described and the literature is reviewed.

Adenocarcinoma↗
PubMed1991

Human chorionic gonadotropin in esophageal carcinomas. An immunohistochemical study.

We have examined immunohistochemically the presence of human chorionic gonadotrophin (hCG) in 29 esophageal carcinomas: 24 squamous cell carcinomas, 2 adenocarcinomas, 2 adenoid cystic carcinomas and 1 adenosquamous carcinoma. In hCG-positive tumors, the presence of human placental lactogen (hPL) and pregnancy-specific beta-1 glycoprotein (SP-1) was also assessed. HCG immunoreactive cells were found in 5 squamous cell carcinomas (21%) and in none of 5 non-squamous cell tumors. The hCG positive cells were found in the most infiltrating areas of the tumors where poorly differentiated and pleomorphic cells predominated. The positive tumors were 4 poorly differentiated (31%) and one moderately differentiated carcinoma (12%). Four out of 10 cases (40%) with lymph node metastases had hCG in the primary tumor, whereas only one out of 11 cases (9%) without metastases was hCG positive. HPL and SP-1 were found in two cases. These placental proteins were detected in similar areas than hCG but the number of hPL and SP-1 immunoreactive cells was lower than hCG positive cells. SP-1 was also seen in areas of squamous cell differentiation negative for hCG. None of these two cases showed trophoblastic differentiation.

Adenocarcinoma↗
PubMed1991

Non-Hodgkin's lymphomas of nasal cavity and paranasal sinuses. An immunohistochemical study.

The authors studied the immunophenotype of nine sinonasal lymphomas using a panel of monoclonal antibodies that react with fixed, paraffin-embedded material (EMA, CAM 5.2, CD45, CD37 [MB-1], MB-2, L-26, CDw75 [LN-1], CD45RA [4 KB-5], CD43 [MT-1], and CD45RO [UCHL-1]). There were seven men and two women, with a mean age of 64 years (range, 9-89 years) and median age of 56 years. Three tumors were limited to the nasal cavity, and the other six had multiple sites of involvement, including the nasal cavity (five), antrum (six), ethmoid (two), orbit (two), and hard palate (one). Histologically, one was a lymphoblastic lymphoma (LBL), one was small cleaved-cell lymphoma (SCCL), three were mixed-cell lymphomas (MCLs), and four were large cell lymphomas (LCLs). Four cases were T-cell lymphomas (one SCCL, three MCLs), four were B-cell neoplasms (four LCLs), and one was of uncertain lineage (LBL). Angioinvasion, coagulative necrosis, and epitheliotropism were seen in the T-cell lymphomas. Extranasal dissemination was seen in four cases: one LBL that involved the lymph nodes, skin, and testes 15 months after diagnosis; one B-LCL that involved the skin 9 months after diagnosis; and one B-LCL and one T-MCL that involved the gastric mucosa and lung simultaneously with nasal presentation. This study shows a higher predominance of B-cell lymphomas in the sinonasal region than previously reported in Oriental populations. However, the T:B ratio of these lymphomas is still greater than that observed for primary lymph node-based neoplasms.

Adolescent↗
PubMed1990

Histological types of laryngotracheal tumors induced in Syrian golden hamsters by nitrosomorpholine and nitrosopiperidine.

The chronic oral administration of nitrosomorpholine (NM) and nitrosopiperidine (NP) to 360 adult Syrian golden hamsters of both sexes resulted in the induction of a high incidence of laryngo-tracheal tumors, which in the group treated with 0.01% solution of NM affected up to 80% of the males. A total of 232 different laryngo-tracheal tumors were found. 36 of these were located within the supraglottic and glottic larynx, 62 were within the subglottic and glottic larynx, and 134 arose within the trachea. Among the laryngeal supraglottic and glottic tumors there were 18 squamous cell carcinomas, 16 squamous cell papillomas and only 2 mixed cell mucoepidermoid papillomas. All the subglottic laryngeal tumors and tracheal tumors were mixed cell mucoepidermoid papillomas. In this study, the squamous cell carcinomas observed within the larynx of hamsters bear morphological and biological similarities to their tumor counterpart found in the larynx of adult man. The laryngeal squamous papillomas observed in this experiment are not similar to the squamous papillomas occurring in man during infancy and childhood. The mixed cell mucoepidermoid papillomas of the hamster trachea and subglottis are a peculiar neoplasm of this species, which morphologically and biologically differs from the cases of tracheal papillomatosis described in man, as well as from the mucoepidermoid tumors of major and minor salivary gland origin also seen in this latter species.

Administration, Oral↗
PubMed1990

WHO International Histological Classification of Tumours. Tentative Histological Classification of Salivary Gland Tumours.

The principles of the proposed modified WHO Histological Typing of Salivary Gland Tumours are based on the following: 1) The classification of tumours is oriented to the routine work of the practicing surgical pathologists, those who do not see tumours of the salivary glands very often. The inclusion of rare, but clearly defined tumour entities should be helpful to surgical pathologists consulting with clinical specialists. 2) The different types of carcinomas must be distinguished not only by precise histopathological definitions, but also considering differences in prognosis and treatment. For example, the polymorphous low-grade adenocarcinoma and the epithelial-myoepithelial carcinoma are characterized by a relatively good prognosis in contrast to the salivary duct carcinoma. 3) Special points of discussion are: subclassification and grading of carcinomas (e.g. acinic cell carcinoma, mucoepidermoid carcinoma and adenoid cystic carcinoma), the classification of basal cell tumours (basal cell adenoma, basal cell carcinoma, solid type of adenoid cystic carcinoma), malignant tumours in pleomorphic adenomas and the differential diagnosis between primary tumours and metastases.

Adenocarcinoma↗
PubMed1990

Subacute cerebellar syndrome as the first manifestation of AIDS dementia complex.

A patient presented with a subacute cerebellar syndrome in absence of cognitive impairment or other symptoms. He became demented several months after the onset of the disease. Necropsy demonstrated the typical features of the AIDS dementia complex and severe loss of Purkinje cells of the cerebellum. Patients with subacute cerebellar dysfunction should be evaluated for the presence of human immunodeficiency virus infection.

AIDS Dementia Complex↗
PubMed1989

Influence of esophagojejunostomy on the induction of adenocarcinoma of the distal esophagus in Sprague-Dawley rats by subcutaneous injection of 2,6-dimethylnitrosomorpholine.

To study the influence of reflux esophagitis on the carcinogenic response of 2,6-dimethylnitrosomorpholine (2,6-DMNM), an experiment was designed, composed of 6 groups of 8-week-old Sprague-Dawley rats, each consisting of 20 males and 20 females. Group 1 served as untreated controls. All animals of groups 2, 4, and 6 underwent an esophagojejunostomy with gastric preservation to produce a chronic reflux esophagitis. 2,6-DMNM was injected s.c. once weekly for life at doses of 1/100 and 1/10 of the 50% lethal dose to groups 3 and 4 and groups 5 and 6, respectively. Carcinogen exposure began in groups 4 and 6 15 days after the esophagojejunostomy. Squamous cell carcinomas were observed in the esophagus of 36 animals, mainly in those receiving the higher dose. Exophytic squamous cell carcinomas, a variety rarely seen in humans, were mostly seen in the groups receiving 2,6-DMNM alone, whereas endophytic squamous cell carcinomas, the variety most frequently seen in humans, mainly developed in the groups receiving the combined treatment. In addition adenocarcinomas with abundant mucin production were found in the distal esophagus of 23 animals. They were found exclusively in animals of groups 4 and 6 which underwent esophagojejunostomy plus 2,6-DMNM exposure. No adenocarcinomas were encountered in groups without experimental reflux esophagitis. These findings may contribute to further understanding of the association between reflux esophagitis and the various histological types of esophageal carcinoma in humans.

Adenocarcinoma↗
PubMed1989

Placental proteins in high-grade urothelial neoplasms. An immunohistochemical study of human chorionic gonadotropin, human placental lactogen, and pregnancy-specific beta-1-glycoprotein.

We examined the presence of human chorionic gonadotropin (HCG) in 16 low-grade and 47 high-grade urothelial neoplasms, including two cases with trophoblastic-like differentiation. In HCG-positive tumors, the presence of human placental lactogen (HPL) and pregnancy-specific beta-1-glycoprotein (SP-1) also was assessed. HCG immunoreactive cells were found in nine of the 47 high-grade tumors (19%), whereas none of the low-grade tumors were positive for HCG. This hormone was predominantly detected in the most undifferentiated and pleomorphic areas; however, HCG-positive cells also were found in areas of carcinoma in situ and well-differentiated transitional cell carcinoma in two cases. The serum HCG level was increased in two of the four cases studied. HPL and SP-1 immunoreactive cells were observed in seven and five cases, respectively, and it was found that tumors positive for SP-1 also were positive for HPL. Five tumors, including the two with trophoblastic differentiation, contained the three placental proteins. The HPL and SP-1 immunostained cells were usually found in the same areas of the tumor that were positive for HCG, but there was always a lower number of HPL and SP-1 immunoreactive cells than HCG immunoreactive cells. In one case, HPL and SP-1 could be found in areas of well-differentiated transitional cell carcinoma. These findings suggest that the morphologic and functional trophoblastic differentiation in urothelial carcinomas is a progressive phenomenon evolving from transitional cell carcinomas.

Adult↗
PubMed1989

Experimental model of tumors associated with neurofibromatosis.

Four groups of animals, each composed of 22 pregnant Wistar rats, were used in this study. Single intraperitoneal (IP) injections of ethylnitrosourea (ENU) at a dose of 15 mg/kg body weight (BW) were given to the animals of two groups on days 15 and 21 of pregnancy, respectively. The progeny of a third group received by subcutaneous injection (SC) the same dose of ENU, 15 mg/kg BW, on day 1 postnatally. The descendants of the fourth group served as untreated controls. The most striking findings were observed in the progeny of the mothers treated on day 15 of pregnancy, in which group 64 of 180 descendants developed peripheral nervous system (PNS) tumors, 30% of which had plexiform pattern. One hundred fifteen of the 180 descendants developed central nervous system (CNS) gliomas, mainly oligodendrogliomas, and five animals presented with Wilms' tumors. No tumors of these types were observed in the untreated controls. Although descendants of mothers treated on day 21 of pregnancy had the highest number of PNS tumors (130 of 172 animals), only 21% of these tumors were plexiform; CNS gliomas were observed in 78 animals and Wilm's tumors in one animal. The lowest percentage of PNS tumors with plexiform pattern (16%) was found in the group of 157 descendants treated postnatally on day 1, in which 88 animals developed PNS tumors, 76 developed CNS gliomas, and no animals developed Wilms' tumors. The higher percentage of plexiform PNS tumors found in the descendants treated prenatally on day 15 of pregnancy was statistically significant (P less than 0.05) when compared with the percentage found in the group treated postnatally. This significance was also valid for the plexiform tumors that developed selectively from branches of the trigeminal nerves (of the PNS tumors from this location, 48% showed a plexiform pattern), but only in the progeny exposed to ENU on day 15 of pregnancy. This same progeny also had the highest numbers of CNS and Wilms' tumors. Because in humans, plexiform neurofibromas are considered to be the neoplastic markers of neurofibromatosis, and CNS gliomas as well as Wilms' tumors are associated with this disease, it is suggested that exposure to ENU on day 15 of pregnancy, under the experimental conditions described here, may offer a model for investigating tumors associated with neurofibromatosis, as well as aspects of the spontaneous, noninherited forms of this disease.

Animals↗