Estudio del ensanchamiento de los conductos radiculares de los primeros molares, instrumentados mecánicamente con el sistema K3 (SybronEndo) / Study of directions of first molar root canal enlargement subjected to mechanical instrumentation with the K3 system

Se ha puesto a punto un sistema para poder evaluar la calidad y cantidad en la preparación de los conductos radiculares usando diferentes sistemas de preparación manual o mecánica de los mismos. En este caso se han testado los nuevos instrumentos mecánicos de Niquel titanio de la casa Sybron/endo comercializados como sistema K3. De las representaciones tridimensionales que se han obtenido después de evaluar los datos numéricos, podemos concluir que el ensanchamiento de los conductos tanto de molares inferiores como superiores ha sido muy centrado en relación al eje inicial del conducto tanto en la zona media coronal como en la media apical. Así mismo se ha podido observar que cuanto más fino es el calibre inicial del conducto mayor es porcentualmente el incremento que se produce en cada uno de los cuatro cuadrantes en los que se divide la superficie del conducto

We have used a technique to evaluate the quality of the different root canal treatments, both manually and mechanically. In this case, we used the new Nickel-Titanium mechanical instruments (sybron/endo), commercially know as k3. From the three-dimensional diagrams obtained from the numerical data, we can conclude that the root canal, in both upper and lower molars, has been widen in a centred way to the initial axis of the conduct, on the media-coronal area as well as on the media-apical area. We could also observe that the thinner the initial diameter of the canal was, gradually, the greater was the size of the different quadrants that we have previously divided the root canal on

[Oligoastrocytoma with signet-ring cell differentiation. A morphological, ultrastructural and immunohistochemical study]. / Oligoastrocitoma con diferenciación en células en anillo de sello. Estudio morfológico, ultraestructrural e inmunohistoquímico.

We present a case of a mixed glial tumor (oligoastrocytoma) with signet-ring cells. This cellular feature is a rare differentiation in glial tumors of the central nervous system. Histological, immunohistochemical and ultrastructural findings have been analyzed. Signet-ring cells showed intense expression with GFAP, S-100 and vimentin. A differential diagnosis with other primary brain tumors and cerebral metástases with signet-ring cell differentiation was discussed.

Oligoastrocitoma con diferenciación en células en anillo de sello. Estudio morfológico, ultraestructural e inmunohistoquímico / Oligoastrocytoma with signet-ring cell differentiation. A morphological, ultrastructural and immunohistoche-mical study

Presentamos un caso de tumor glial mixto (oli-goastrocitoma) con células en anillo de sello. Esta diferenciación celular es rara en tumores gliales del sistema nervioso central. En este estudio analizamos las características morfológicas, ultraestructurales e inmunohistoquímicas del tumor. Las células neoplásicas con características morfológicas en anillo de sello mostraban expresión de GFAP, S-100 y vimentina. En la discusión consideramos el diagnóstico diferencial con otros tumores primarios del sistema nervioso central, así como con metástasis cerebrales de neoplasias con diferenciación en células en anillo de sello (AU)

Trabecular trajectory in the articular processes of the human fourth cervical vertebra.

The articular processes (AP) of the neural arch have been implicated in weight transmission through the cervical spine. To analyse the mechanism of weight transmission in the AP, we studied the direction of forces within it, in particular, the pattern of trabecular trajectories. Twenty-two AP from C4 vertebrae were studied in anatomical sections, and corresponding photoelastic models from selected sections were constructed and analysed. Anatomical and photoelastic findings show the subarticular spongiosa of the superior articular process (SAP) to be orthogonally arranged with vertical and oblique trabeculae in the direction of compressive forces and additional trabeculae always oriented perpendicular to the former. Vertical and oblique trabeculae are divided into rostral, middle and posterior groups. Rostral and middle trabeculae end in the anterior wall of the SAP and the transitional zone with the pedicle. Posterior trabeculae end in the subarticular spongiosa of the inferior articular process (IAP). The findings relating to trabecular trajectories in the SAP differ from previous descriptions and instead suggest that a part of the weight forces distributed within the AP transmit to the subchondral zone of the IAP. Knowledge of the trajectorial architecture of the AP may contribute to refining finite element analytical models for investigating its weight-bearing function.

Histopathological and cytogenetic findings in benign, atypical and anaplastic human meningiomas: a study of 60 tumors.

Meningiomas may display benign (grade I), atypical (grade II) and anaplastic (grade III) histopathological findings. The cytogenetic studies strongly suggest that secondary changes (beyond loss of chromosome 22) appear to be associated with more atypical features and with greater clinical aggressivity. We studied 60 tumors from 52 patients. Histopathological features such as nuclear pleomorphism, nucleolar prominence, mitosis, necrosis, cellular density, PCNA labeling index, and karyotype have been evaluated. The distribution in histological grades was: 50% benign, 33% atypical and 17% anaplastic meningiomas. Nuclear pleomorphism and nucleolar prominence showed a progressive increase in grades I, II and III. Multifocal micronecrosis was considered a criterion of malignancy. A significant correlation was observed between PCNA-LI, mitotic index and grades. Complex karyotypes increased progressively: benign (34% of cases), atypical (45% of cases) and anaplastic (70% of cases). The most common numerical alterations were losses of chromosomes 10, 14, 18 and 22. The chromosomes most often involved in structural anomalies were: 1, 4, 7, 14 and 22. Telomeric associations were present in four cases and double minutes in two cases. Prognostic criteria for these tumors have been analyzed on the basis of these data.

Histopathological and cytogenetic findings in benign, atypical and anaplastic human meningiomas: a study of 60 tumors.

Meningiomas may display benign (Grade I), atypical (Grade II) and anaplastic (Grade III) histopathological findings. The cytogenetic studies strongly suggest that secondary changes (moreover loss of chromosome 22) appear to be associated with more atypical features and with greater clinical aggressivity. We studied 60 tumors from 52 patients. Histopathological features such as nuclear pleomorphism, nucleolar prominence, mitosis, necrosis, cellular density, PCNA labeling index, and karyotype have been evaluated. Nuclear pleomorphism and nucleolar prominence showed a progressive increase in Grades I-III. Multifocal micronecrosis was considered a criterion of malignancy. A significant correlation was observed between PCNA-LI, mitotic index and grades. Complex karyotypes increased progressively: benign (34% of cases), atypical (45% of cases) and anaplastic (70% of cases). The most common numerical alterations were losses of chromosomes 10, 14, 18 and 22. The chromosomes most often involved in structural anomalies were: 1, 4, 7, 14 and 22. Telomeric associations was present in four cases and double minutes in two cases. Prognostic criteria for these tumors have been analyzed on the basis of these data.

Proliferating cell nuclear antigen (PCNA) as a prognostic factor in renal cell carcinoma.

BACKGROUND: A retrospective study was performed on patients with renal cell carcinoma to determine whether tumoral proliferating cell nuclear antigen (PCNA) is a predictive factor. METHODS: We studied immunohisto-chemical PCNA expression with pc10 monoclonal antibody in 109 renal tumor paraffin sections. These tumors were previously classified according to cellular type by Thoenes, Furman's grading and Robson's staging, Moreover, we counted the number of mitoses in 10 high power fields (HPF) and also evaluated the tumoral necrosis percentage. Ten year survival curve of Kaplan and Meier was obtained for 90 patients. RESULTS: Nuclear immunostaining for PCNA showed a statistical correlation with Robson's stage, cellular type and nuclear grade. Moreover, the number of positive nuclei was higher in tumors presenting an elevated mitosis count and higher in degree of necrosis. Survival was significantly poorer in patients whose PCNA index was greater than 5%. Nuclear PCNA immunostaining was shown to be an independent prognostic factor in patients with Robson stage I and also in those who had high cytological grading. CONCLUSIONS: These results show PCNA to be a prognostic marker for RCC.

[Meningiomas with disomy of chromosome 22: study of 9 cases]. / Meningiomas con disomía del cromosoma 22: estudio de 9 casos.

BACKGROUND: Cytogenetic studies of meningiomas suggest that loss of (or parts of) chromosome 22 is a primary event in the development of these tumors; later on, other chromosomal changes would occur in the caryotypes. All these secondary changes are observed mainly in cases with high clinical aggressivity. However, in a few cases of meningiomas disomy 22 coexists, but with other chromosomic anomalies. We present clinical, histopathological and cytogenetic findings in a group of meningiomas with disomy of chromosome 22. PATIENTS AND METHODS: We collected 10 meningiomas from nine patients which ages ranged between 28-70 years. Fresh tumoral specimens were divided for histologic examination and cytogenetic study, performed after short-term culture. RESULTS: At microscopic examination 5 tumors were classified as benign meningiomas, four as atypical and one as malignant meningioma. Four cases were recurrent tumors. The cytogenetic studies showed that all tumors presented two chromosomes 22 and other chromosome abnormalities. Losses in chromosomes 4, 7, 10, 14, 16, 17 and 20 were frequent; cytogenetics rearrangements of chromosomes 1, 4, 5, 7, 14, 19 and 22 were frequently involved. CONCLUSIONS: In karyotypic evolution of meningiomas, secondary anomalies of chromosomes 1p, 10 and 14 are the most common and appear to be associated with a more aggressive clinical course. In this group of meningiomas with disomy 22, these anomalies were also frequently found, and were related in 50% of cases with atypical or malignant morphologies and of them with recurrent tumors in the 40%.

FU-3 monoclonal antibody: a specific marker for malignant fibrous histiocytoma? An analysis of 32 malignant soft tissue and bone sarcomas.

An immunohistochemical study on frozen sections was carried out on 51 malignant tumours of soft tissue and bone using the FU-3 monoclonal antibody. This antibody is claimed to be specific for malignant fibrous histiocytoma (MFH) and liposarcoma and for normal and tumour cells located in perivascular fields. The results show a lack of specificity in MFH staining: several malignant tumours such as synovial sarcoma, fibrosarcoma, rhabdomyosarcoma, osteogenic sarcoma, and including an anaplastic malignant melanoma, presented positive staining somewhat similar to that found in MFH. The value of this antibody in the differential diagnosis of MFH is doubtful. It might be useful to recognize a common pathway of terminal differentiation expressed by several pleomorphic sarcomatous neoplasms.

[The determination of tissue CEA in colorectal adenocarcinomas: an immunohistochemical study]. / Determinación del CEA tisular en adenocarcinomas colorrectales: un estudio inmunohistoquímico.

We carried out a CEA immunohistochemical study on 80 colorectal carcinomas, using the PAP methodology. Also we studied peritumoral "normal" mucosa on 69 cases. All tumoral (80/80) and the major part of normal colonic mucosa (68/69) cases stained positively. We present our experience with this immunohistochemical staining using a qualitative semi-quantitative evaluation, as an easy and reliable procedure. This permits to obtain, by immunostaining, a better homogeneous group of tumours (Apical, Mixed and Cytoplasmic, or Weak and Strong), necessary to further correlation with various tumoral parameters. On the basis of this evaluation, we found: A staining of weak intensity (65/68) of Apical type (55/68) in the vast majority of the normal, peritumoral mucosa. In tumors we found a prevalence of strong intensity (67/80), in relation to its major content of CEA. With respect to the type of immunostaining, although Apical staining (32/80) exists the Cytoplasmic (34/80) is predominant together with the Mixed type (14/80). This is expression of the alterations in secretion and distribution of the tissue CEA. We analyze the difficulties of such classification caused by the tumoral heterogeneity and we include other data whose significance is not always clear.

[A correlation between serum levels of preoperative CEA and CEA immunohistochemical staining in colorectal carcinoma]. / Correlación entre niveles séricos de CEA preoperatorios y tinción inmunohistoquímica del CEA en el carcinoma colorrectal.

We analyzed the distribution of tissue CEA in 80 colorectal adenocarcinomas with the PAP immunohistochemical technique. We used a qualitative method with a double grading criterion--topography and intensity of staining--as well as a semiquantitative method in the immunostaining interpretation. We applied a pattern of immunostaining: apical, cytoplasmic or mixed, to each tumor. Likewise, we obtained the pre-operatory serum levels of CEA. The normal value in our laboratory is less than 10 ng/ml. We correlated the immunostaining pattern with the serum levels of CEA, obtaining a global statistical significant correlation (p < 0.01), as well as apical versus cytoplasmic correlation (p = 0,0,3). The apical staining pattern agreed with this CEA levels < 10 ng/ml, whereas the cytoplasmic staining was associated with high frequency with CEA levels > 10 ng/ml. In conclusion the immunohistochemical staining for tissular CEA permits to improve the prognostic efficiency of serum CEA levels.

Micropharmacology of monoclonal antibodies in solid tumors: direct experimental evidence for a binding site barrier.

Monoclonal antibodies (MAbs) often distribute nonuniformly in tumors. In part, that observation reflects intrinsic heterogeneity within the tumor; in part, it reflects poor penetration through tumor substance. Several years ago, we proposed the "binding site barrier" hypothesis (J.N. Weinstein, R.R. Eger, D.G. Covell, C.D.V. Black, J. Mulshine, J.A. Carrasquillo, S.M. Larson, and A.M. Keenan, Ann. NY Acad. Sci., 507: 199-210, 1987; K. Fujimori, D.C. Covell, J.E. Fletcher, and J.N. Weinstein, Cancer Res., 49: 5656-5663, 1989), the idea that antibodies (and other ligands) could be prevented from penetrating tumors by the very fact of their successful binding to target antigen. Calculations suggested that this might be a significant factor in the therapy of even microscopic nodules. The higher the affinity and the higher the antigen density, the greater the barrier. Here, we provide direct experimental evidence of such a barrier to the percolation of D3 MAb through intradermally implanted line 10 carcinoma of guinea pigs. After affinity purification using glutaraldehyde-fixed line 10 cells, the D3 had an average immunoreactivity of 88%, a binding constant of 1.6 +/- 0.3 (SEM) x 10(10) M-1, and saturation binding of 355,000 +/- 15,000 molecules/cell. Using a combination of double-label autoradiography and double-chromagen immunohistochemistry, we determined simultaneously the distribution of (a) i.v. injected D3 MAb; (b) coinjected isotype-matched control IgG (BL3); (c) D3 antigen; (d) blood vessels. The previously developed mathematical models aided in the design of these experiments. Double immunochemical staining of the tumors showed antigen-rich patches 100-800 microns across, surrounded by blood vessels. At a low MAb dose (30 micrograms), binding to antigen severely hindered penetration into antigenic patches as small as 200 microns, even at 72 h. Explanation of this finding by a physical barrier was ruled out by the observation that BL3 distributed uniformly in the same patches. At a higher dose (1000 micrograms), the binding site barrier could be partially overcome. The same general principles of micropharmacology may apply to biological ligands other than antibodies, including those secreted by genetically modified cells.

Morphometric and immunohistochemical characterization of bladder carcinoma in situ and its preneoplastic lesions.

We performed a morphometric and immunohistochemical study of 26 bladder carcinoma in situ (Cis) specimens, compared with normal urothelium and urothelial preneoplastic lesions. The following morphometric parameters were evaluated: nuclear area, nuclear perimeter and maximum nuclear diameter. For the immunohistochemical study we used five lectins, antibodies against four epithelial differentiation antigens, and antibodies against blood group isoantigens. A progressive increase in nuclear size from normal urothelium to dysplastic urothelium and Cis was detected. Nuclear size values in Cis and in high-grade, high-stage bladder carcinomas were similar. The most relevant immunohistochemical results were obtained with CEA, CK, UEA-1 and ABH isoantigens, which show significant immunoreactivity changes in preneoplastic urothelium and Cis when compared with normal urothelium. We conclude that bladder Cis behaves morphometrically and immunohistochemically as an invasive bladder carcinoma, and we emphasize the usefulness of these techniques for detecting flat dysplastic and neoplastic lesions in random bladder biopsies.

DNA-ploidy, morphometric-stereological and P-glycoprotein study of superficial bladder carcinomas.

We carried out a DNA-ploidy, morphometric-stereologic and P-glycoprotein study on 40 newly diagnosed superficial bladder cancer patients (G1-G2), correlating the results with histological grade and clinical outcome. Variations in the number of patients who present recurrences, progression or remain tumor-free during the whole follow-up period (at least 5 years) were not significant when related to nuclear size, proliferative diploid index, presence of aneuploidy and expression of P-glycoprotein. It is striking how the majority of disease-free subjects showed a proliferative diploid index higher than 10%. Moreover, 3 of them presented an aneuploid cell population. In our study, only histological grade showed a significant discriminatory level in terms of progression versus no progression in patients with superficial bladder cancer.

Behavior of epithelial differentiation antigens (carcinoembryonic antigen, epithelial membrane antigen, keratin and cytokeratin) in transitional cell carcinomas of the bladder.

Results of an immunohistochemical study in normal urothelium and transitional cell carcinomas of the bladder are presented. Paraffin-embedded material was confronted with immunoantisera against carcinoembryonic antigen (CEA), keratin (K), cytokeratin (CK) and epithelial membrane antigen (EMA). Immunohistochemical findings confirm the changes in reactivity of dysplastic urothelium and carcinoma in situ for CEA, CK and EMA, in comparison with normal urothelium. Statistically significant differences were also found, depending upon tumor stage, in staining of transitional cell carcinomas for K and CK. Expression of CK correlated with the tumor differentiation grade: normal urothelium and well-differentiated carcinomas showed a specific pattern of immunostaining for the basal cells, this pattern being lost in poorly differentiated carcinomas.

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.

[Orbital myositis: an ultrastructural and immunohistochemical study]. / Miositis orbitaria: Estudio ultraestructural e inmunohistoquímico.

We present a morphological and ultrastructural study from one case of orbitary myositis in a 35 years old male patient with asymmetrical localytation and clinical behaviour as a tumor. The morphological study shows a chronic inflammatory lesion which causes atrophy and necrosis of the muscular tissue. On the ultrastructural image it is remarkable the atrophy of the muscle fibers with loos of the sarcomers, joined with signs of regeneration. The inflammatory infiltrate is polimorfous, with T and B cells immunihistochemically detected. There is also a macrophagic population identified by the morphology and immunohistochemistry with positivity for alfa-1-chymiotrypsin and alfa-1-anti trypsin. An important fibroblastic activity is show. On the discussion a possible pathogenesis for this entity is considered.

[Tumors of the choroid plexus: morphologic and immunohistochemical study]. / Tumores de plexos coroides: estudio morfológico e inmunohistoquímico.

We present a morphological and immunohistochemical study on three papillomas and one carcinoma of the choroid plexus. Clinical characteristics are analysed. Morphological criteria for malignancy are: solid histological pattern, cellular polymorphism, nuclear atypia and infiltration of nervous tissue. The immunohistochemical study shows the value of GFAP, S-100 protein, HNK-1 and Vimentin as specific markers. In the discussion we point out the differential diagnosis between these types of tumors and the metastasis from papillary carcinomas and ependymomas.

[Differential immunohistochemical characteristics of meningiomas and other neoplasms of the central nervous system]. / Características inmunohistoquímicas diferenciales de los meningiomas con otras neoplasias del S.N.C.

We present an immunohistochemical study of 16 meningiomas and 19 CNS tumors including gliomas, neurinomas and metastatic carcinomas, in order to establish a histopathologic differential diagnosis, using formalin-fixed and paraffin-embedded material. The antibodies analysed included vimentin, GFA-protein, cytokeratin, S-100 protein and epithelial membrane antigen. Meningiomas always express vimentin as marker, and occasionally cytokeratin and EMA. The most constant antigens demonstrated in astrocytomas were GFA-protein and vimentin, and occasionally we were able to detect S-100 protein. Neurinomas proved positive to S-100 protein, and metastases presented cytokeratin and EMA reactivity. Our results confirm the existence of diverse immunohistochemical patterns within CNS tumors, a fact that can be useful in routine differential diagnosis.