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C Carda

Publications and source records attributed to C Carda.

36 records · Page 2Linked to original sources
PubMed1997

Molecular alterations of the RB1, TP53, and MDM2 genes in primary and xenografted human osteosarcomas.

We report the status of the RB1, TP53, and MDM2 genes in human osteosarcomas and cell lines established from surgical specimens and transplanted into athymic naked mice. By using reverse transcriptase-polymerase chain reaction (RT-PCR) as a prescreening technique and posterior sequencing, we observe new mutations in the RB1 gene, notably a duplication in tandem of exons 3 through 6. TP53 mutations appear in codons most frequently mutated in osteosarcomas. We have not seen MDM2 gene amplification in any reported case. These molecular alterations appear in different osteosarcomas not simultaneously present in the same tumor sample. A link has been described between these three genes in the pathways that control the cell cycle and the tumoral progression, but their functions are probably independent in the development of osteosarcomas. TP53 mutations appear in adult patients, whereas RB1 alterations occur mostly in younger patients.

Adolescent↗
PubMed1996

Young's syndrome: a further cause of chronic rhinosinusitis.

Three males--aged 32, 35, and 27 years--presented Young's syndrome: a combination of obstructive azoospermia and chronic sinopulmonary infection. The evaluation of nasal mucociliary transport using an isotopic technique revealed mucociliary stasis in one case and decreased clearance in the others (< 2 mm/min). Ciliary ultrastructure was normal in two patients, while the other showed mucous hyperplasia and low ciliary density which made correct ciliary evaluation not possible. The clinical development of this syndrome is chronic, although less severe than in the other two syndromes that exhibit primary failure of mucociliary transport: cystic fibrosis and primary ciliary dyskinesia. Young's syndrome should be considered in the differential diagnosis of patients suffering from chronic rhinosinusitis, particularly with cystic fibrosis and primary ciliary dyskinesia syndrome.

Adult↗
PubMed1995

Clinical and ultrastructural correlations in nasal mucociliary function observed in children with recurrent airways infections.

A study was made of 106 children between 1 and 15 years of age (mean 6 years) with recurrent upper and lower airways infections since birth. Nasal mucociliary transport (NMT) velocity was determined in all subjects by the Tc99m-labeled seroalbumin technique. In 42 children, NMT was found to be altered. In this group of patients the technique was repeated in a period of between 1 and 2 years later. In 23 cases (55%) transport had normalized, while in 19 (45%) it remained altered. Recurrent pneumonia and constant rhinorrhea were more frequent in this group. Situs inversus was only detected in 2 of these patients. Pathology showed ciliary ultrastructure, the absence of dynein arms and microtubule alterations. The absence of cilia was observed in some patients. Normal cilia were also encountered in children with persistently altered nasal mucociliary transport.

Adolescent↗
PubMed1995

[The prevalence of primary dyskinetic ciliary syndromes in patients with sinusitis and bronchiectasis].

In this paper are studied the prevalence of this syndrome (the PDCS) in 18 patients affected either of chronic sinusitis or bronchiectasias. Fourteen cases (77%) fulfil the diagnostic requirements in order to be considered as PCDS. Clinical differential features with regard to the idiopathic group are: situs inversus, male's infertility, perennial rhinorrhea and secretory otitis media. Mucociliary transport is studied through an isotopic technique and resulted absent in the PDCS group, being normal in the idiopathic one. The ultrastructure of nasal cilia is normal in the idiopathic representative, while in the cases with PDCS was verified the total or partly lack of dyneine arms in 8 cases, without cilia 3 cases, surnumerary central microtubules 3 cases and surnumerary peripheral microtubules in 2 cases. One sufferer of Kartagener's syndrome showed cilia structure in accordance with standard pattern.

Adolescent↗
PubMed1995

Small round cell tumors of bone and soft tissue. A morphometric and stereometric comparative analysis of 119 cases.

OBJECTIVE: To analyze the discriminative capability of morphometric assessment of nuclear morphology in the differential diagnosis of small round blue cell tumors (SRCTs) of bone and soft tissue. STUDY DESIGN: The study material consisted of glutaraldehyde-fixed, resin-embedded, semithin sections from 119 human tumors. Nuclear area, perimeter, maximum diameter, form factors and nuclear density were measured in at least 300 nuclei per case. RESULTS: Neuroblastoma (NB) (10 cases) showed the most regular pattern. Ewing's sarcoma (ES) (35 cases); atypical Ewing's sarcoma (AEs) (15 cases) and peripheral neuroectodermal tumors (PNET) (30 cases) showed no significant differences regarding area, perimeter or form factors, but AEs showed a lower mean nuclear density that was statistically significant. Rhabdomyosarcomas (6 cases) and osteosarcomas (OS) (11 cases) were used as controls and showed several morphometric and stereometric differences with other SRCTs, whereas microcellular OSs (6 cases) shared features of SRCTs and conventional osteosarcomas. CONCLUSION: Morphometric characterization of nuclear features reveals differences between the distinct groups of SRCTs. Although overlapping occurred between all these groups at the individual case level, this study provides new support for the existence of morphologic links within the family of ES and PNET.

Bone Neoplasms↗
PubMed1994

EWS/FLI-1 rearrangement in small round cell sarcomas of bone and soft tissue detected by reverse transcriptase polymerase chain reaction amplification.

Recent cloning of the t(11;22) region has led to the detection of a number of sequences involved in the breakpoints by substituting a sequence which encodes a putative RNA binding domain for that of the DNA binding domain of the human homologue of murine FLI-1. Several tumours display consistent translocation at t(11;22) (q24;q12), a finding that suggests these fusion transcripts could be expressed and detected by reverse transcriptase polymerase chain reaction amplification. To date, only a small number of Ewing's sarcomas (Es) and peripheral neuroectodermal tumours (pPNET) of bone have been tested with this novel molecular biology approach. In this study, we confirmed the presence of the three putative chimaeric transcripts on 7 cases of Es and pPNET sarcomas of bone and soft tissue, providing 100% positivity for the tested tumours. For comparative purposes, a number of other neuroectodermal tumours were analysed with negative results: esthesioneuroblastoma, retinoblastoma, Schwannoma. A primitive soft tissue sarcoma (ectomesenchymoma) with a 22 chromosome rearrangement did not express any transcript, nor did a number of non-neuroectodermal small round cell sarcomas of soft tissue (rhabdomyosarcomas) and bone (microcellular osteosarcoma), conventional bone sarcomas, leiomyosarcomas, malignant fibrous histiocytomas and synovial sarcomas. These results reinforce the value of molecular biology techniques for the correct assessment of histology difficult evaluable neoplasms, such as the group of small round cell tumours within the Es family.

Animals↗
PubMed1994

Aluminium allergy in patients hyposensitized with aluminium-precipitated antigen extracts.

During hyposensitization therapy with aluminium-precipitated antigen solutions, a small % of patients develop persistent subcutaneous nodules at the injection site; the existence of delayed sensitivity to aluminium has been implicated in the pathogenesis of these nodules. We studied the prevalence of aluminium sensitivity (using patch, prick and intradermal tests) and common contact allergens (TRUE Test) in 20 healthy subjects, and in 40 patients treated with aluminium-containing extracts, 20 of whom had persistent subcutaneous nodules that remained for more than 2 months, the other half having no nodular reactions or nodules that remained for less than 2 months. Aluminium sensitivity was found only in those patients of the treated group who had persistent nodular reactions, 4 cases of positivity to an aluminium chloride patch test being found. All 4 cases were women, nodules remained for more than 6 months, and intracutaneous tests were negative. 3 of them also had contact sensitivity to nickel. In 2 cases, nodules were removed for histological and histochemical examination, showing non-specific inflammatory granulomas, and aluminium crystals being found in only 1 case. It is concluded that delayed sensitivity to aluminium appears to be implicated in the pathogenesis of persistent nodular reactions, but sensitivity to aluminium was not found in patients treated with aluminium-precipitated extracts without persistent nodular reactions.

Adolescent↗
PubMed1990

Soft tissue Ewing's sarcoma. Characterization in established cultures and xenografts with evidence of a neuroectodermic phenotype.

This study characterizes the histogenesis of soft tissue Ewing's sarcoma (StEs) based upon an analysis of three tumors. Long-term cultured cell lines and nude mice xenografts were established from original neoplasms or from their metastases. Histologically they revealed a small round cell pattern without signs of differentiation. Several ultrastructural features of neural type were found; the same were also seen on culture cell lines. Moreover, immunohistochemical study for neural markers revealed the presence of HNK-1, NSE, LIRC-LON 36, S-100 protein, glial fibrillary acidic protein, neurofilaments (70 kilodaltons), and chromogranin; some of these markers were present only in the transplants. Cytokeratin was also seen. The translocation t(11;22)(q24;q12) was found in all three neoplasms together with other chromosomal abnormalities. N-myc RNA gave negative results whereas c-myc RNA was expressed. Therefore it may be postulated that StEs displays neuroectodermal features somewhat similar to those seen in peripheral neuroepithelioma as well as in atypical Ewing's sarcoma of bone.

Adolescent↗
PubMed1989

Giant-cell tumor of bone, stage II, displaying translocation t(12;19)(q13;q13).

A new case of giant-cell tumour (GCT) of bone with benign histological features, clinical stage II, has been reviewed with immunohistochemistry and electron microscopy. After short-term tissue culture the karyotype, using G-banding techniques, presented a consistent translocation t(12;19)(q13;q13). Nude mice xenografts of the tumour were unsuccessful after 6 months of follow-up. Presence of such chromosomal rearrangement may be related to locally aggressive, histologically benign giant-cell tumors of bone.

Adult↗
PubMed1989

Pigmented esthesioneuroblastoma showing dual differentiation following transplantation in nude mice. An immunohistochemical, electron microscopical, and cytogenetic analysis.

Esthesioneuroblastoma (ESTH) is a neuroepithelial-cell-derived neoplasm of the olfactory mucosa composed of homogeneous small round cells which contain neurosecretory granules. Melanin has been detected in such tumours only occasionally. Here we describe a new case of ESTH with divergent differentiation. The primary neoplasm was found in a 67 year-old female, involving the left nasal and maxillary sinus; she died of cerebral metastasis ten months after diagnosis. Histologically only small round cells were seen, with S-100 and NSE positivity. Electron microscopy revealed neurosecretory granules and filaments, as well as the occasional presence of melanosomes. A nude mice xenograft line has been established, and is presently in its ninth transfer. Two cell types are present: small round-to-spindle shaped cells with neural features, and large epithelial-like ones. Both immunohistochemistry and electron microscopy confirm this dual differentiation, with the presence of membrane-bound dense-core neural secretion, as well as melanosomes of neuroectodermal origin. Additionally, an in vitro cell line has been established. Cytogenetic analysis confirmed the presence of both malignant human melanoma patterns; non-random abnormalities in chromosomes 1 and 6, extra copies of chromosome 7. Duplication of the long arm of chromosome 14, as seen in olfactory neuroblastoma, is also seen.

Aged↗
PubMed1989

[Oral hairy leukoplakia. A study of 5 cases].

Oral hairy leukoplakia (HL) is a newly described lesion (1984) in human immunodeficiency virus infected patients. Patients with HL show a high probability of developing an acquired immunodeficiency syndrome (AIDS). The results of histopathological, microbiological, immunological and ultrastructural studies in five patients with HL and AIDS are reported. The histopathological exam revealed in all cases acanthosis, parakeratosis, koilocytosis and keratin projections on the surface. Dermis was normal. Herpes type virus were seen in four cases and in one of them papilloma virus was also present in electron microscopic examination. There was immunocytochemical evidence of papilloma virus in one lesion. Candida albicans was found in 5 lesions by culture but only in two ones by periodic acid Schiff stain. Virus cultures for herpes virus were negative. Immunocytochemical search of Langerhans cells (S-100, HLA-DR, OKT4, OKT6) showed nearly absence of these cells in HL lesions. These results favour the viral etiology hypothesis of hairy leukoplakia.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Value of nude mice xenografts in the expression of cell heterogeneity of human sarcomas of bone and soft tissue.

Nude mice xenotransplants have been performed on human primary sarcomas of bone and soft tissues in order to delve into the cell heterogeneity of these neoplasms. Particular emphasis has been given to the group of small round blue cell sarcomas (Ewing's sarcomas and peripheral neuroectodermal tumors). Out of 31 xenotransplanted sarcomas, 16 cases have grown positively, and many of them continue to be transferred into nude mice on a regular time basis, being presently considered as fully established nude lines. Here we report the results of such a system, which has been followed with optical, electron microscopical, immunohistochemical and cytogenetic techniques. Osteosarcomas make up the group with the highest number of positivities taken (6 out of 9 transplanted cases). Diversity in growth rate, positive tumors and morphology are taken into consideration. Epithelial foci were seen in one of the transplanted neoplasms. Malignant fibrous histiocytoma and other mesenchymal sarcomas of bone and soft tissues are reviewed. Changes in immunohistochemical reactivity (alpha-1AT and alpha-1AQT) were observed in the transplanted neoplasms. Cytogenetic analysis performed on an undifferentiated (primitive) soft-tissue sarcoma provided clues to its synovial origin. Analysis of Ewing's sarcoma performed on nude mice transplanted tumors shows heterogeneous immunohistochemical response, with enhancement of cytokeratin positive cells, not previously seen in the primary neoplasms.

Animals↗
PubMedDate not supplied

[Prevention of ossification after total hip endoprosthesis with indomethacin and its effect on gastric mucosa].

The administration of indomethacin as a prophylactic against heterotopic ossification following the implantation of total hip-joint endoprosteses entails the risk of gastrointestinal side-effects. A prospective randomized study set out to determine the effectiveness of ranitidine and sucralfate as a secondary treatment for the protection of the stomach. Comparison with a placebo group monitored at the same time confirmed the efficacy of both medicaments. Both ranitidine (2 x 150 mg) and sucralfate (4 x 1 g) were able to prevent the occurrence of ulcers of the mucous membrane of both stomach and duodenum. Thanks to postoperative prophylactic treatment with indomethacin (2 x 50 mg for 3 weeks), there were no serious ossifications (degree II or III according to Arqu).

Adult↗
PubMedDate not supplied

[Primary ciliary dyskinesia: functional and morphological study].

We present 7 patients with a typical symptomatology of immotile cilia syndrome, three of them with complete situs inversus. Nasal mucociliary transport was studied by sero-albumin marked with technetium 99m. In all cases there was an absence of transport. The ultrastructure of the nasal cilia was studied. The findings were: In four cases alterations in the dynein arms, in three cases alterations in the central and peripheral microtubules associated por not to the defects in the dynein arms, and in one cases absence of cilia were observed. The ciliary complexes were common to all cases.

Adolescent↗
PubMedDate not supplied

[Clinical and ultrastructural evaluation of nasal mucociliary function in HIV-positive patients. Preliminary investigation].

Nasal mucociliary transport was studied in 33 HIV-positive patients with different stages of infection. Ciliary ultrastructure was studied in 8 of these cases. At the time of study, 24 patients had respiratory infections. Disturbances in mucociliary transport were found in 25 cases. In 6 of the 8 studies of ciliary ultrastructure, changes in the ciliary axonema were found, particularly in the central and peripheral microtubules.

Adult↗
PubMedDate not supplied

[Incomplete ciliary axonema: anther cause of ciliary dysmotility syndrome?].

Immotile cilia syndrome is associated with different ciliary defects, although the clinical presentation is similar in every case. A study was made of a 36-year-old woman with recurrent respiratory infections since birth, chronic sinusitis and chronic bronchitis with bronchiectasias. Her medical history included a tubaric pregnancy and two miscarriages. Nasal mucociliary transport was investigated on two occasions at a 1-year interval using an isotopic technique. Ciliary ultrastructure was studied by electron microscopy after obtaining two biopsies from the inferior and middle turbinates separated by a 1-year interval. The sweat test and blood immunoglobulins were normal. The absence of mucociliary transport was verified on both occasions. An abnormality was observed in 30% of the cilia in the form of semicircular ciliary cross-sections, with only 7 pairs of peripheral microtubules. The central pair was normal. We termed this anomaly "incomplete ciliary axonema" and believe that it could be another cause of immotile cilia syndrome.

Adult↗