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PubMed2001

Analysis of genetic alterations in salivary gland tumors by comparative genomic hybridization.

In order to define and map chromosomal copy number alterations in salivary gland tumors (SGTs), a comparative genomic hybridization (CGH) technique was applied to two pleomorphic adenomas (PAs), one adenoid cystic carcinoma (ACC), and one basal cell adenocarcinoma (BCAC). The PAs exhibited regional copy number losses at 5q12.4-q14.1, 9q12-q21.13, and 16q11.2, as well as a gain at 20p12.1; among these, the losses at the 9q12-q21.11 and 16q11.2 regions were common to both PAs. The ACC showed overrepresentations of the entire regions of chromosomes 16 and 20, a regional gain at 22q12.3-q13.1, and no losses. In the BCAC, regional gains at 9p21.1-pter, 18q21.1-q22.3, and 22q11.23-q13.31 as well as losses at 2q24.2 and 4q25-q27 were seen; the gain at 22q12.3-q13.1 was common in both the ACC and the BCAC. These CGH data indicate that different genetic alterations are present in the different types of SGTs, and that the alterations involve several chromosomes. The discovery of common alterations in the same and/or different types of tumors might be important in the understanding of the development and progression of the SGTs.

Adenoma, Pleomorphic↗
PubMed1990

Morphological, morphometric and stereological study of submandibular glands in rats with lesion of the anteroventral region of the third ventricle (AV3V).

Lesions of the antero-ventral region of the third ventricle induce in the rat submandibular gland parenchyma, atrophy through vascular ischemia, and simultaneously increased fibrosis of the connective tissue, probably by alteration of the pituitary gonadotropins (FSH, LH), thyrotrophic hormone (TSH), growth hormone and probably insulin levels.

Animals↗
PubMed1990

Blood vessel endothelia of the cerebral white matter of rats exposed to hypoxia. Karyometric and cytophotometric evaluation.

Hypoxic hypoxia is used as one of the models for examining the unfavourable effect of oxygen deficit on the nervous system. Since some morphological studies concerning the effect of hypoxia on the central nervous system have given consideration to perivascular lesion zones and glia alterations in the white matter, the present evaluation of the effect of hypoxia has been directed to vascular endothelia of the white matter. Examinations were conducted on adult rats of the Wistar strain which were exposed to acute hypoxia by being placed in a gas mixture containing 2% O2 or to moderate hypoxia - in a gas mixture containing 7% O2. Experimental animals were sacrificed 4 and 24 h after hypoxia and 14 and 60 d after hypoxia. The behaviour of vascular endothelia after hypoxia was evaluated by karyometric and cytophotometric methods. The measurements show an edema of endothelial nuclei in capillaries of the cerebral white matter of the rat in the first 24 h after hypoxia accompanied by nuclear chromatin index alterations proportional to the intensity of hypoxia. The measurements of endothelial nuclei 14 and 60 d after hypoxia show a development of a degenerative process in these nuclei, manifested by their decreasing size and by nuclear chromatin concentration in their central parts. The morphometric and cytophotometric examinations point to long-term alterations induced by hypoxic hypoxia.

Animals↗
PubMed1988

Karyometric and cytophotometric studies of the oligodendroglia in the corpus callosum of the rat after hypoxia.

Karyometric and cytophotometric investigations were conducted using an automatic analyser "Morphoquant" on oligodendroglial nuclei of corpus callosum following acute or moderate hypoxia in Wistar rats. Results of our studies demonstrated karyometric changes in nuclei of oligodendroglia cells after hypoxia, with deviations distinct in the early and late period after exposure to hypoxia. Cytophotometric analysis of a relative DNA content in cell nuclei of oligodendroglia demonstrated an increased extinction of DNA in the early period and a decreased extinction in the late period after acute or moderate hypoxia. The changes in oligodendroglia may be primarily responsible for the molecular structure lesion in myelin, observed as a result of hypoxia.

Animals↗
PubMed1979

DNA synthesis and endomitoses in the giant nuclei of the silkgland of Bombyx mori.

At the first symptoms of organisation of the silkgland in the embryo, mitoses stop and nuclei start to grow. Through autoradiographic studies, performed after sequenced labeling with [3H] and [14C] thymidine, the durations of the different phases of DNA synthesis cycles (T = 42 to 48 h, S = 22 to 25 h, G = 20 to 23 h) are established. These durations are in fact identical during the second and the third instar, and the same, whatever region is concerned : posterior, middle or anterior parts. A model has been established to account for the distribution of the S phases during the second and third instars. The DNA synthesis in all nuclei of a given region has been followed during the first four instars by labelling with [3H]thymidine. The activity goes through maxima and minima, depending on the percent of nuclei synthesizing DNA and their synchronism, both being characteristic of each region; long resting periods are observed during the molting stages of the first three instars in the middle and the anterior parts. The coincidence is obvious between the maxima and minima and respectively the S and G phases of the model. DNA assays agree with the distribution of cycles established by autoradiography if one admits that each cycle does lead to a doubling of the amount of DNA. The overall DNA synthesis from the diploid value is estimated to correspond to 18-19 endomitoic cycles in the nucleic of the posterior part, 19-20 cycles of those of the middle part and 13 in those of the anterior part. The analysis of chromosome structures, by squashing the nuclear content, shows that existence of a complete endomitotic cycle: the doubling of chromosomes is associated with condensed structures, alternating with a decondensed state of chromatin, responsible for the DNA synthesis. The female heterochromatin undergoes a restricted morphological cycle delayed with respect to bulk chromatin. It is characterized by a late DNA duplication and by non dispersed daughter chromosomes. Some of these aspects are, to a lesser extent, reproduced in groups of autosomic chromosomes.

Animals↗
PubMed1978

Morphology of osteosarcoma: new qualitative and quantitative investigations.

Results on seven cases of osteosarcoma are reported, based on new morphologic methods and quantitative procedures. Tumor tissue was embedded without prior decalcification in plastic and sectioned. Imprint cytology preparations were produced from fresh tumor tissue, and cell nuclei were measured with an electronic image analysing computer system. The loss of differentiation seen in osteosarcomas differs among osteoblasts, osteocytes, and osteoclasts. The differentiation of osteoclasts, namely their resorptive characteristics, disappears relatively early. Tumor osteocytes show loss of differentiation in their osteocyte processes. The new formation of tumor bone tissue remains in the near normal range of volume density when nuclear polymorphy is limited. The formation of ground substance and mineralization are apparently closely couplet to one another, since in our cases mostly ordered osteoid seams were observed. The capacity for mineralization of bone tissue is lost with marked polymorphy. The significance of these results for diagnostic statements and therapeutic consequences will be further discussed in long term studies.

Adolescent↗
PubMed1978

Reversible morphological changes of rectal mucosa in vitamin B12 deficiency.

The histomorphology of the rectal mucosa in a case with pernicious anemia was studied before and after treatment with vitamin B12. In the vitamin-deficient state the mucosa exhibits a decrease in the number of mitoses and an increase in the nuclear diameter and nuclear-cytoplasmic ratio. These changes return to normal after vitamin administration. The reversible morphological alterations may serve as an example for the importance of vitamin B12 in maintaining the structure and possible the function of the rectal mucosa.

Aged↗
PubMed1982

Sex dimorphism of the adrenal cortex in rats after treatment with dexamethasone.

Sex dimorphism of adrenal cortex of the rat was studied by light and electron microscopy as well as the karyometric, gravimetric, and histometric methods after treatment with dexamethasone (2.0 mg/kg over a period of 4 days). Sex dimorphism cannot be shown in dexamethasone-induced atrophy of adrenal glands. Male fasciculata cells have more and finer distributed liposomes resembling in this way female fasciculata cells. Normally present differences in adrenal weight and nuclear size of fasciculata cells between both sexes disappear; nevertheless, female fasciculata cells remain relatively bigger compared to the corresponding male cells. Annulment of sex dimorphism is thought to be the result of altered functional activity of the zona fasciculata due to failing pituitary stimulation. Higher secretion activity of female fasciculata cells probably ceases after dexamethasone treatment.

Adrenal Cortex↗
PubMed1984

Metastasizing APUD cell tumours of the human gastrointestinal tract. Light microscopic and karyometric studies.

A total of 11 metastasizing gastrointestinal APUD cell tumours from biopsy and autopsy files were reclassified according to Soga and Tazawa as well as to WHO Histologic Classification of Tumours. The much higher proportion of APUD cell tumours in autopsies (11 cases from 1000 autopsies in comparison with 22 cases from 22 000 biopsies) demonstrate that the majority of them will not be discovered during the patient's life. EC cell carcinoids (type A) predominate in both non-metastasizing and metastasizing gastrointestinal APUD cell tumours. Metastases from EC cell carcinoids occurred only in regional lymph nodes and in the liver. The APUD cell tumours originating in the pancreas represent the most frequently metastasizing gastrointestinal carcinoids. Besides in the liver and in regional lymph nodes metastases from pancreatic APUD cell tumours were seen in the skin, the brain and the skeleton. One case with two (pancreatic, bronchial) competitive primary APUD cell tumours and a skin metastasis was studied by means of automated cell image analysis. Cell populations of these three tumour sites were characterized by morphometric and densitometric nuclear parameters. It could be demonstrated that the skin metastasis consisted of a cell population, which occurred as a subpopulation in the primary tumour of the bronchus. The results of karyometric investigations supported the hypothesis that single components of tumours can metastasis selectively.

Adolescent↗
PubMed1989

Multiparametric quantitation of the progression of uterine cervix preneoplasia towards neoplasia.

The aim of the research was to quantify the malignancy progression of preneoplastic lesions towards carcinoma of the uterine cervix. The study has shown that the modifications to nuclear area, perimeter, DNA content, percentage of nuclei with nucleoli, nuclear/cytoplasmic ratio and percentage of SOYA BEAN AGGLUTININ stained cells are progressively greater moving from normal epithelium and mild dysplasia towards infiltrating carcinoma. In particular all the morphologic and histochemical parameters have shown an increasing derangement which appears to parallel the diploid reduction and the appearance of aneuploidy. In order to identify the changes in the stroma, the modifications to the capillaries were investigated: in mild dysplasia only the vessel density increases; the capillary area, perimeter and diameter increase in moderate and severe dysplasia, and in CIS; the values of these features are similar in the carcinoma groups. The capillary density increases mainly in the invasive carcinoma. The data obtained in the study have shown that: 1) the process of malignancy progression is characterised by a gradual and continuous derangement of cell characteristics and modifications to capillaries of the stroma; 2) the mild dysplastic changes have the characteristics of hyperplastic lesions; 3) CIS, qualitatively similar to severe dysplasia from which it differs quantitatively, has features of neoplastic proliferation; 4) the appearance of invasion is associated with DNA parameter changes which may indicate a ploidy reduction.

Capillaries↗
PubMed1996

Stereological evaluation of malignant mesothelioma versus benign pleural hyperplasia.

The differential diagnosis between malignant mesothelioma and benign pleural hyperplasia constitutes a well-known problem. In the present study we examined unbiased stereological techniques to assess the mean nuclear volume (MNV) using the point-sampled intercepts (PSI) in 37 cases of malignant mesothelioma and in 28 cases of benign pleural hyperplasia. Neither the use of different fixatives nor the histological type of malignant mesothelioma produced any significant difference on the measured nuclear volume. The differences observed between the MNV data obtained from benign pleural hyperplasia and those from any of the three types of malignant mesothelioma were found to be highly significant. All lesions with an MNV larger than 250 microns3 were found in our study to correspond to the malignant mesothelioma type, while an MNV that was smaller than 200 microns3 could only be detected in benign specimens. These observations lead us to propose the MNV measurement using PSI as an additional tool to enhance the differential diagnosis of malignant mesothelioma versus benign pleural hyperplasia.

Cell Nucleus↗
PubMedDate not supplied

Human sperm morphometry and smoking, caffeine, and alcohol consumption.

The purpose of this study is to determine whether sperm nuclear size, shape, and chromatin texture parameters are associated with lifestyle exposures including smoking, caffeine, and alcohol consumption. Eighty-six healthy male volunteers (ages 18-35), recruited through newspaper advertisements, provided a semen, blood, and urine sample and completed a questionnaire concerning demographic and lifestyle exposures. Sperm nuclear size, shape, and chromatin texture parameters were measured using computerized image analysis. Results indicated no associations between the sperm nuclear morphometric parameters and age, smoking, or alcohol consumption. There was weak evidence for an association with caffeine intake. In conclusion, the lifestyle factors smoking, caffeine intake, and alcohol consumption do not appear to significantly affect sperm nuclear size, shape, or chromatin texture in this study population.

Adult↗
PubMed1996

Cytogenetic analysis of salivary gland type tumors.

Fourteen salivary gland type tumors were analyzed with a combination of conventional cytogenetics via GTG-banding, molecular cytogenetics via fluorescent in situ hybridization, and chromosome morphometry. Nine tumors were benign (eight pleomorphic adenomas and one Warthin tumor) five tumors were malignant (one carcinoma ex pleomorphic adenoma, two adenoid cystic carcinomas including one from the breast, a basal cell adenocarcinoma, and an acinic cell carcinoma). Thirteen specimens grew in tissue culture; the basal cell adenocarcinoma did not grow. The Warthin tumor had a normal karyotype, one pleomorphic adenoma was normal, one had a clone with a missing Y chromosome, and the other pleomorphic adenomas had structural chromosomal abnormalities including the following: translocations between chromosomes 3 and 8, chromosomes 6 and 16, chromosomes 8 and 9, chromosomes 8 and 12, chromosomes 8 and 14, and chromosomes 8 and 21. Of the four malignant tumors with karyotypes, the acinic cell carcinoma and one adenoid cystic carcinoma were normal, the second adenoid cystic carcinoma showed a normal polymorphic variant, whereas the carcinoma ex pleomorphic adenoma demonstrated the following karyotype: 46,XX,dir ins(8;5)(q12;q12q35), add(12)(p13)/46,XX. In conclusion, 66% of the benign tumors and 25% of the malignant tumors demonstrated abnormal karyotypes.

Adenolymphoma↗
PubMed2004

Dynamics of homologous chromosome pairing during meiotic prophase in fission yeast.

Pairing of homologous chromosomes is important for homologous recombination and correct chromosome segregation during meiosis. It has been proposed that telomere clustering, nuclear oscillation, and recombination during meiotic prophase facilitate homologous chromosome pairing in fission yeast. Here we examined the contributions of these chromosomal events to homologous chromosome pairing, by directly observing the dynamics of chromosomal loci in living cells of fission yeast. Homologous loci exhibited a dynamic process of association and dissociation during the time course of meiotic prophase. Lack of nuclear oscillation reduced association frequency for both centromeric and arm regions of the chromosome. Lack of telomere clustering or recombination reduced association frequency at arm regions, but not significantly at centromeric regions. Our results indicate that homologous chromosomes are spatially aligned by oscillation of telomere-bundled chromosomes and physically linked by recombination at chromosome arm regions; this recombination is not required for association of homologous centromeres.

Cell Nucleus↗
PubMed2004

Dictyostelium discoideum talin A is crucial for myosin II-independent and adhesion-dependent cytokinesis.

Cytokinesis in myosin II-null (mhcA-) cells of Dictyostelium discoideum requires adhesion to a substratum. Moreover, such myosin II-independent, adhesion-dependent cytokinesis can be divided into two distinct classes: a cell cycle-coupled form (cytokinesis B) and a cell cycle-independent form (cytokinesis C). To better understand the mechanisms underlying cytokinesis B and C, we introduced mutations into mhcA- cells and isolated clones that consistently gave rise to large, multinucleated cells. One such clone was found to have a disrupted talA gene, which codes for one of two Dictyostelium homologues of talin. Time-lapse observation revealed that cytokinesis B is partially impaired in mhcA-/talA- cells and that cytokinesis C is completely blocked. MhcA-/talA- cells took significantly longer to complete cytokinesis B than mhcA- cells on regular polystyrene surfaces, but not on a more adhesive surface. During cytokinesis B in mhcA- cells, GFP-TalA localized in the cortex and in dot-like structures on the ventral surface. Like vertebrate talin, these TalA dots may be involved in substrate adhesion and provide the traction needed to efficiently carry out cytokinesis B. During cytokinesis C in mhcA- cells, GFP-TalA was localized in the cortex of future furrow regions, and was highly enriched in cytoplasmic bridges that formed as the furrowing proceeded. Analysis of furrows in which GFP-TalA concentrations were asymmetric suggested that cortical TalA prevents formation of leading edges in regions where its concentration is high and indirectly promotes formation of leading edges elsewhere, which causes passive furrowing of the TalA-rich regions.

Actins↗