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Gioconda Dobrescu

Publications and source records attributed to Gioconda Dobrescu.

8 recordsLinked to original sources

Computerized morphometric discrimination between normal and tumoral cells in oral smears.

The oral exfoliative cytology allows a quick and fairly accurate assessment of suspicious lesions of the oral cavity. Within this context, our paper proposes a quantitative approach, focusing on the construction of a classifier for detecting the presence of the tumoral cells on oral smears. The design of the classifier relies on a detailed computerized analysis of the individual morphometric features exhibited by two large known populations of normal and tumoral cells, respectively; the digital image processing was performed in the Zeiss KS400 environment. The classifier was implemented as a neural network with step activation function, whose parameters were obtained from an adequate training, based on the nuclear and cytoplasmic areas of the cells belonging to the two populations. Our procedure based on this classifier was meant to operate by identifying the tumoral or normal nature of any cell randomly selected from a smear. To identify the nature of an arbitrary cell, its nuclear and cytoplasmic areas are presented at the input of the classifier. The classification procedure was tested on several smears, and the results coincided with the pathological diagnosis in all the considered cases. The performances of our approach are discussed in comparison with other analytical methods previously reported in oral exfoliative cytology. These discussions emphasize the role of numerical information exploited for the classifier design, concluding that the individual morphometric features are more meaningful than the global characterization of smears by mean values.

Carcinoma, Squamous Cell↗

[Electron microscopy study regarding the etiology and the pathogenesis of acne vulgaris].

The etiology and the pathogenesis of acne vulgaris are not complete cleared up yet. This work presents the results of the electronomicroscopic examinations effected on lesions of acne vulgaris biopsied from 5 patients with different clinical forms of disease (including acne fulminans). In this study we had in view the investigation and description of the ultrastructural modifications that followed the intervention of the 4 factors incriminated in the etiology and pathogenesis of acne: sebaceous hypersecretion, hyperkeratosis pilosebaceous infundibulum, bacterial colonisation, perifollicular inflammation. The ultrastructural aspects that we had in view underline the role of the 4 etiology and pathogenesis factors of acne vulgaris, confirming the data related by the specialised literature.

Acne Vulgaris↗

[Electron microscopy in oral squamous cell carcinoma of elderly patients].

OBJECTIVES: Squamous cell carcinoma is the most frequent tumor occurring in the oral cavity. The aim of the study is to point out the fine-structural characteristics of the tumor cells and of the adjacent stromal cells, trying to establish a correlation between these characteristics and the biological behavior of the tumor. MATERIAL AND METHODS: We performed an electron microscopic investigation for tree elderly patients diagnosed with oral squamous cell carcinoma. RESULTS: The tumoral cells presented nuclear abnormalities and the reduction of the intercellular cohesion, through an increase in the intercellular spaces, and desmosomal modifications. Through the abundance and the variety of the cellular types, the stromal component represented a positive response from the host. CONCLUSIONS: In the diagnosis of the oral carcinoma, the electron microscopic exam supplements the light microscopic investigation, revealing important morphologic elements at a subcellular level (regarding the nucleus, cellular organelles, and junctions).

Aged↗

[Hyperthyroidism and coexistent thyroid carcinoma].

The association between thyrotoxicosis and thyroid cancer is a classical, rare and controversial entity. Within their series of eleven such cases the authors dissociate two distinct groups from clinical and pathological viewpoint. The first category is represented by one case of follicular thyroid cancer with clinically and biologically confirmed hyperthyroidism. The second group includes ten patients with thyrotoxicosis (three cases with Graves' disease, four with toxic multinodular goiter and three with toxic adenoma) and associated unsuspected occult or nodular carcinoma. None of these patients had received previous treatment with radioiodine. In all cases the diagnosis was established by pathological examination of the surgical specimen. Surgery is the treatment of choice in these lesions, the presence of carcinoma imposing the extent of operation. Five near total thyroidectomies and three near total lobectomies with ablation of the isthmus was performed in our cases associated with appropriate additional measures: TSH suppression or 131I treatment. Post surgical results were satisfactory without morbidity or mortality. The long-term survey was good (seven cases alive after 5 years).

Adenocarcinoma, Follicular↗

[Pulmonary alveolar proteinosis in AIDS patients].

We present 4 patients with pulmonary alveolar proteinosis and AIDS which died in Infectious Disease Hospital Iaşi in the interval January 2002-March 2003. The pulmonary tissue from the necropsy exam was stained with H.E., PAS, Alcian blue and Mucicarmine. The macroscopical examination revealed multiple yellow-gray nodular areas (>2 cm) of consolidation. Microscopically, the alveoli were filled with a delicate, granular, acidophil material that was periodic acid Schiff (PAS) positive. The intraalveolar material was Alcian blue and Mucicarmine negative, too.

Acquired Immunodeficiency Syndrome↗

[Transcriptional and electron microscopic analysis of extracellular matrix proteoglycans in acute acetaminophen intoxication].

UNLABELLED: Acetaminophen (APAP) OTC regimen is not compatible with kidney and liver toxic effects. In order to further understand the determinism of the repair process, we have studied the expression of some target extracellular matrix proteoglycan components in an animal model. MATERIALS AND METHODS: An acute APAP toxic dose (800 mg/bw) was administered to 45 mice aged 1 month. At 24 hours, tissue samples were processed for light microscopy, electromicroscopy and RT-PCR analysis. RESULTS: Extensive necrotic lesions involving hepatocytes and tubular epithelial cells associate strong positivity for proteoglycans, detected as convoluted filaments with lateral projections, frequently associated with collagen fibers, cell surface and other matrix components. Overexpression for perlecan, syndecan 1 and 4 and low expression for biglycan was assessed by RT-PCR. CONCLUSIONS: Extracellular matrix and cell surface components are early involved in both lesional mechanism and repair reaction post acetaminophen injury.

Acetaminophen↗

[The detection of dysplastic lesions of the gallbladder mucosa in polypoid cholelithiasis].

AIM: To investigate the hyperplastic and/or dysplastic lesions in the gallbladder mucosa. METHODS: We used the immunohistochemical Ardeleanu-Hsu-Bussolati and Gugliotta methods, with avidin and peroxide biotin, adapted in the laboratory of University Hospital "St. Spiridon" Iaşi. There were studied ten cases of polypoid cholelithiasis, with the following markers: Ki67, PCNA, and p53. RESULTS: The immunohistochemical methods using Ki67, PCNA and p53 protein allowed the evaluation of the abnormal proliferation abilities characteristic for some hyperplastic or dysplastic lesions, found in our cases of cholelithiasis. CONCLUSIONS: The utilization of these markers permitted us to establish a good correlation between the high activity of Ki67 and the morphological aggression indicators in hyperplastic and dysplastic gallbladder epithelium. There is also a correlation between the percentage of the cells marked with anti-PCNA antibody and the existence of p53 protein in these lesions.

Biomarkers, Tumor↗