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R Alberti

Publications and source records attributed to R Alberti.

12 recordsLinked to original sources
PubMed1992

Cytologic diagnosis of non-oxyphil follicular neoplasias of the thyroid. Multivariate classification procedure based on quantitative nucleolar features.

The study was done on cytologic material of 58 non-oxyphil follicular neoplasias of the thyroid, 32 of which were adenomas and 26 carcinomas. Three groups of nucleolar features were quantified using a routine microscope with an ocular micrometer: frequency-, size-, and margination-related features. Since value overlap was present between two categories for all the variables, stepwise discriminant analysis was applied. The following three features were selected by the computer for calculation of one canonical discriminant function: percentage of marginated nucleoli, percentage of nuclei with one nucleolus, mean major nucleolar diameter. The percentage of agreement between morphologic and computer classifications was 95%. Two follicular adenomas were allocated to the carcinoma category, whereas one follicular carcinoma was allocated to the adenoma category. Out of 58, 52 were diagnosed by the computer into one of the two diagnostic categories with a very high probability, i.e. P greater than 0.75, the remaining 6 being considered intermediate.

Adenoma↗
PubMed1992

Well differentiated follicular neoplasms of the thyroid: reproducibility and validity of a 'decision tree' classification based on nucleolar and karyometric features.

This study was conducted on fine-needle aspirates of well differentiated follicular neoplasms of the thyroid. A 'decision tree' classification based on the percentage of nucleolated nuclei, percentage of nuclei with two or more nucleoli and mean major nuclear diameter was adopted. We observed that the reproducibility and the validity of the follicular adenoma vs follicular carcinoma discrimination are greater than in the subjective evaluation. Moreover, similar classification results were obtained when measurements were performed either with a fully automated image analysis system or with semiautomatic or manual instrumentation. As for reproducibility of the inter-instrument comparisons, the k statistic values ranged from 0.85 to 1.00 (mean value 0.90, that is, an 'almost perfect' degree of agreement); in the subjective evaluations, the inter-observer comparisons showed values ranging from 0.20 to 0.56 (mean value 0.37, that is, 'fair'). In the decision tree classification, feature value thresholds were selected in order to have specificity of 100% and the predictive value of a positive result (carcinoma) of 100%; accuracy was 87% (range 86-89%), sensitivity 74% (71-79%), the predictive value of a negative result (adenoma) 79% (78-82%). In the subjective evaluation the values were as follows: accuracy 67% (64-71%), sensitivity 57% (50-64%), specificity 77% (71-79%), predictive value of a negative result (adenoma) 64% (61-69%), predictive value of a positive result (carcinoma) 71% (67-75%). The conclusion is that, by using a routine microscope equipped with a micrometer, the preoperative diagnosis of follicular carcinoma from smears can be formulated with a high degree of certainty.

Adenocarcinoma↗
PubMed1992

Cytometric evidence that cervical intraepithelial neoplasia I and II are dysplasias rather than true neoplasias. An image analysis study of factors involved in the progression of cervical lesions.

Image analysis was performed on 40 Feulgen-stained histologic samples and 48 Feulgen-stained cytologic preparations representing normal squamous epithelium and all grades of cervical lesions (from mild dysplasia to invasive carcinoma) in order to characterize the evolutionary progressive changes in cervical epithelial proliferative disease toward malignancy. Quantitative studies included the analysis of proliferative features, differentiation features, nuclear morphology and DNA content. The data obtained on the histologic sections showed that the various features, to a different extent, detected a gradual increase in phenotypic cellular disarrangements related to the progression of the cervical lesions toward malignancy--that is, the modifications to nuclear area, perimeter, DNA content, percentage of nuclei with nucleoli, nuclear/cytoplasmic ratio and percentage of cells with no membrane positivity for soybean agglutinin lectin were progressively greater, moving from normal epithelium and mild dysplasia toward infiltrating carcinoma. In particular, all the morphologic and histochemical features appeared to parallel a diploid reduction and the appearance of aneuploidy. The simultaneous evaluation of proliferation- and differentiation-related features, together with those of nuclear DNA content, showed two main successive preneoplastic lesions: one characterized by an increase in cell turnover without alterations in its organization and another by a true neoplastic disorder. The data obtained on sequential cytologic examinations showed that individual cell changes are detectable and seem basically to be characterized by the appearance of clusters of cells with somatic characteristics not observed in previous cytologic checks. From the results of our study, the cervical intraepithelial neoplasia (CIN) concept appears to be inaccurate. In fact, only CIN III (severe dysplasia/carcinoma in situ) lesions have the morphologic and proliferative alterations of true neoplasia. In contrast, CIN I and some cases of CIN II lesions lack these characteristics and seem to be properly classified as dysplasia, thus avoiding the term neoplasia, implicit in CIN. Moreover, the multivariate study of data sets of features related to the progressive somatic changes, both in histologically and cytologically studied cases, allows us to detect the steps of progression; they are marked by the appearance of cell clusters with qualitatively different phenotypic characters when compared to the cell populations from which they presumably arise. These results seem to provide a further argument against the CIN theory, which stresses the concept that progression is related only to a gradual numerical increase in an initially established phenotype with the characteristics of malignancy.

Biopsy↗
PubMed1991

Quantitative analysis of nucleolar margination in diagnostic cytopathology.

The diagnostic value of nucleolar margination, defined as the percentage of nucleoli touching the nuclear membrane, was investigated in 359 cytological preparations of benign and malignant lesions of the thyroid, breast, prostate and central nervous system. Premalignant lesions of the uterine cervix and non-invasive papillary carcinomas of the bladder were also examined. It was observed that the percentages in benign lesions were, in general, lower than in the malignant and that the values increased progressively with increasing grade in the cervix and bladder. When the overlap index was calculated, this gave exact information on the usefulness of nucleolar margination in distinguishing benign from malignant lesions, particularly in the prostate and thyroid and, to a lesser extent, in the breast and central nervous system. As for lesions of different grades, the calculation of the index allowed the identification of two subgroups, one corresponding to low grades (mild cervical dysplasia or urothelial papillary carcinoma of grade 1), the other subgroup to high grades (severe cervical dysplasia and carcinoma in situ, or papillary carcinoma of grade 3). Moderate dysplasia cases and grade 2 papillary carcinomas do not appear as separate intermediate categories but rather show values falling into the range of either the higher or lower grades. The margination values obtained from the cytological preparations corresponded well to those in the histological slides obtained from the resected specimens. In conclusion, nucleolar margination appears to be a feature which is easy to evaluate in a reproducible way and useful in cytological diagnosis.

Biopsy, Needle↗
PubMed1991

Value of quantitative nucleolar features in the preoperative cytological diagnosis of follicular neoplasias of the thyroid.

Nucleolar prevalence, size, and outline were investigated on cytological material from cold thyroid nodules obtained by fine needle aspiration. The percentage of nucleolated nuclei in follicular adenoma (32 cases) was less than in follicular carcinoma (26 cases). In adenoma most nuclei contained one nucleolus, and nuclei with two or more nucleoli were less common than in carcinoma where most cases showed the highest nucleolar diameter values. There was some overlap between adenomas and carcinomas, however, when the mean of the 10 largest values of the major nucleolar diameter was considered. In follicular carcinoma the percentage of marginated nucleoli--that is, those touching the nuclear membrane--was, in general, greater than 20%; in adenoma the values were equal to or lower than 16%. The overlap index showed that the percentages of marginated nucleoli and nucleolated nuclei are the two best discriminatory features between adenoma and carcinoma.

Adenocarcinoma↗
PubMed1991

Red cell distribution width, free erythrocyte protoporphyrin, and England-Fraser index in the differential diagnosis of microcytosis due to iron deficiency or beta-thalassemia trait. A study of 200 cases of microcytic anemia.

Microcytic anemias are often encountered in clinical practice. In most cases they are due to iron deficiency, but in some geographical areas other diagnoses, such as that of beta-thalassemia trait, must be considered. In some cases, the hematological data presented by the automated hemogram may be very similar in both entities, showing moderate anemia, microcytosis, and increased red blood cells. From a practical point of view, it may be important to make an "at-first sight" diagnosis using simple parameters that may readily be obtained from the hemogram or from the laboratory. We have assessed the usefulness of RDW (red cell distribution width), of the England-Fraser index and of free erythrocyte protoporphyrin determination in predicting iron deficiency anemia or beta-thalassemia trait. Our results suggest that the most accurate of these parameters is the England-Fraser index, but that a presumptive diagnosis of beta-thalassemia trait can correctly be made if RDW and FEP values are near normality.

Adolescent↗
PubMed1990

Quantitative analysis of prostatic intraepithelial neoplasia on tissue sections.

The changes in nuclear morphology (karyometry) and DNA content in prostatic intraepithelial neoplasia (PIN) were analyzed on tissue sections. The cases of PIN were subdivided into PIN 1 and PIN 2 based on the degree of proliferation and the anaplasia of the secretory cells lining the ducts and acini. Cases of nodular hyperplasia (NH) and adenocarcinoma were also studied for comparative purposes. Karyometric analysis showed a progression of most values from NH to PIN to carcinoma. The DNA analysis showed a decrease in the frequency of nuclei in the diploid range and an increase in the percentage of nuclei in the other ploidy regions (especially between 2c and 4c and in the tetraploid range) from NH to PIN to carcinoma. Forward stepwise discriminant analysis showed similarities between NH and PIN 1 and between PIN 2 and carcinoma. These findings suggest that the evolution towards adenocarcinoma is characterized by progressive morphologic derangements of the nuclei and by the transformation of the diploid DNA content into a nondiploid one, with the changes taking place at the level of PIN 2.

Adenocarcinoma↗
PubMed1978

Decrease of alpha-Hasharon globin in beta-thalassaemia.

In time course experiments performed in subjects carrying haemoglobin Hasharon and beta-thalassaemia the synthesis of alphaA-, alphaHasharon-, beta- and gamma-globin has been determined. The alpha-globin molecules synthesized in excess were found to be removed from the red cell cytoplasm (phenomenon characteristic of beta-thalassaemia, described by Bargellesi et al, 1968a); in addition the alphaHasharon-globin molecules were removed at a faster rate than normal alpha-globin. The preferential removal of the mutant alpha-globin explains the reduced level of haemoglobin Hasharon found in subjects carrying the gene for beta-thalassaemia (Alberti et al, 1975). Reductions below normal levels of other haemoglobin variants occurring in the presence of the counterpart-globin thalassaemia are probably determined through a similar mechanism.

Genes↗
PubMed1977

Hemoglobin Gavello - alpha 2 beta 2 47 (CD6) Asp replaced by Gly. A new hemoglobin variant from Polesine (Italy).

During a survey for abnormal hemoglobins in Polesine (a region north of the Po river, where beta-thalassemia is very frequent) a slow moving variant was noted in a 79-yr-old woman living in Gavello, a small town in the province of Rovigo. Structural studies demonstrated a previously undescribed amino acid substitution, beta47 Asp replaced by Gly. This new variant has been named Hb Gavello.

Aged↗
PubMed1975

Haemoglobin Hasharon in a north Italian community.

A survey of haemoglobin variants undertakin in an Italian community (Polesine) has revealed the presence of haemoglobin Hasharon (alpha2 47 Asp yields His beta2) in 108 subjects from 40 families. The variant accounted for 30 to 40% of the total haemoglobin. In subjects doubly heterozygous for Hb Hasharon and beta thalassaemia, the proportion was 17 to 19%. Though there was some evidence that the variant was unstable in vitro, there was no obvious haemoglobinopathy in vivo.

Amino Acids↗