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At least 685 records · Page 38Linked to original sources
PubMed1984

Spermatocytic seminoma. Ultrastructural and microspectrophotometric observations.

Spermatocytic seminoma of the testis is a specific clinicopathologic entity and a unique germ cell neoplasm without a homologous counterpart in the ovary or in extragonadal sites. Six spermatocytic seminomas were subjected to a detailed ultrastructural study, and seven spermatocytic seminomas were analyzed using microspectrophotometry. Five classic seminomas were also subjected to microspectrophotometric analysis for comparison. Ultrastructurally, spermatocytic seminoma cells were shown to contain a larger number of cytoplasmic organelles than classic seminoma, but they did not exhibit structures that are diagnostic of cells capable of meiotic division and precursors of acrosomes. Microspectrophotometric analysis confirmed the absence of haploid cells and indicated that spermatocytic seminoma cells have lower modal numbers than classic seminoma cells. The majority of spermatocytic seminomas exhibit hyperdiploid or peritriploid DNA modal values, whereas in classic seminomas these values range from peritriploid to peripentaploid. These findings support the view that spermatocytic seminoma represents a better differentiated variant of seminoma than the classic type, but they oppose the view that spermatocytic seminoma is composed of spermatocytes capable of meiotic division. It is considered that spermatocytic seminoma is composed of cells differentiating in the direction of spermatocytes but which have not yet reached this stage of differentiation.

Cell Differentiation↗
PubMed1984

[Tumor cell kinetics in uterine cervical carcinoma following irradiation].

15 cases of squamous cell carcinoma of uterine cervix which received radiotherapy were investigated in order to elucidate tumor cell kinetics following irradiation. The DNA content of Pararosanillin-Feulgen stained tumor cells were measured by fluorescence cytophotometry which provided great precision in the field of microspectrophotometry. Besides the cell preparation, tumor cells were precisely identified under blue light excitation (405nm). It is of great value to obtain a reliable DNA histogram of tumor cells with this method. In both groups of radioresistant cases (n = 3) and radiosensitive cases (n = 12), the same trend in cell kinetics was noted until 1400 rad, such as G2-block, endoreduplication, and a decrease in the 2c cell (G0 + G1) population. Most of the residual cells at 3000 rad of radioresistant cases showed little irradiation-induced morphological change. These cells were proved to be 2C cells in this study. This indicates that these radioresistant cells were non-cycling cells (G0). The mean value for the 2C cell population before irradiation was 65% in radioresistant cases and 46% in radiosensitive cases, respectively. The former contained a larger proportion of 2C cells than the latter. Clinically, the 2C cell population before irradiation may be used as a useful parameter to forecast radiosensitivity.

Aged↗
PubMed1984

DNA content of hyperplastic and neoplastic acinar cell lesions in rat and human pancreas.

Pancreatic acinar cell hyperplastic lesions and neoplasms in rats and humans were studied for their nuclear DNA content by microspectrophotometry. Atypical hyperplastic acinar cell lesions induced in rats by azaserine displayed a wide range of DNA contents, 1.5-8C for those composed of acidophilic-type cells and 1.5-9C for those of basophilic-type cells compared with the euploid pattern of 1.5-5C in acinar cells in normal pancreas. The modal DNA values of rat acinar cell adenomas were distributed over an even wider range of 2-11C. In human pancreas, hyperplastic acinar cell lesions composed of eosinophilic-type cells displayed a slightly wider range of DNA content (1.5-8C) than that in surrounding normal acinar cells (1.5-5C). The DNA histograms of basophilic acinar cell lesions were of an aneuploid pattern (2-12C) similar to that of an acinar cell carcinoma (2-15C). These findings demonstrate that acinar cell hyperplastic lesions in rats and humans have an altered genetic complement and suggest that they probably are precursor lesions for acinar cell neoplasms.

Adenoma↗
PubMed1983

[Biological essence of the squamous-cell structures in 2-component endometrial cancer].

Combined comparative study of anatomo-histological features, proliferative activity, content of X-chromatin, and ploidy of the nuclei of epithelial structures of 7 adenoacanthomas, 8 glandular-squamous cell carcinomas, and 7 adenocarcinomas (control group) of the endometrium was carried out. Microspectrophotometry of DNA revealed heterogeneity in DNA content and polyploidy typical of malignant growth in all cell populations, including squamous cell component of adenoacanthomas. The correlation between reduced degree of histological differentiation, depth of invasion, and decreased number of nuclei containing X-chromatin bodies as well as the occurrence of histological transitions suggest that adenoacanthomas and glandular-squamous cell carcinomas should be regarded as one group of two-component endometrial tumors and the terms used for their designations as synonyms. Within this group, highly and poorly differentiated variants may be distinguished which is of prognostic importance.

Adenocarcinoma↗
PubMed1984

Action spectrum of photomechanical cone contraction in the catfish retina.

The action spectrum for the photomechanical contraction of catfish single cones was found to fit the absorbance spectrum of the visual pigment they contain (determined by microspectrophotometry). This indicates that cone contraction is brought about by a direct effect of light on the cones themselves and not, as is the case for the epithelial pigment, by an indirect effect via the rods.

Animals↗
PubMed1984

The macular pigment. I. Absorbance spectra, localization, and discrimination from other yellow pigments in primate retinas.

The nonbleaching yellow pigments of the primate fovea were studied by microspectrophotometry (MSP). Retinas fixed with glutaraldehyde/paraformaldehyde mixtures retained yellow pigments with absorbance spectra very similar to those recorded by MSP in fresh retinas. This allowed the authors to prepare retinal sections for localization of the pigments. The spectrum of the macular pigment in fixed tissue is shifted slightly (about 6 nm) toward longer wavelengths, with maximum absorbance at 460 nm. Two short-wavelength yellow pigments also have been identified, with absorbance maxima at 410 nm ( P410 ) and 435 nm ( P435 ), respectively. All three yellow pigments are present in the fovea. The short-wavelength pigments are detected more easily outside the central foveal region because the macular pigment does not obscure them there. They are especially apparent when the MSP beam is confined to the outer nuclear layer or the inner segment layer of retinal sections. The macular pigment is most dense in the fiber layers (receptor axon layer and inner plexiform layer); its density declines markedly with retinal eccentricity. The maximal absorbance of P410 and P435 is usually lower than that of the macular pigment in the central fovea, but their densities and relative proportions change more gradually with eccentricity. Consequently, their maximal absorbance is higher than that of the macular pigment outside the foveal center. The P410 and P435 pigments may be two different oxidation states of one or more respiratory hemoproteins. Commonly used procedures for estimating the absorbance spectrum of the macular pigment by comparing the foveal center with a parafoveal region may be influenced by the amounts and the oxidation states of the short-wavelength pigments in the living eye.

Animals↗
PubMed1984

Hemoglobin content of individual erythroblasts in hematopoietic dysplasia: marked heterogeneity at late stages of maturation.

Defective hemoglobin synthesis and gross morphologic abnormalities of erythroblasts are striking features of hematopoietic dysplasia. In order to define the effects of defective hemoglobin synthesis on hemoglobin content of erythroblasts at each stage of maturation, we measured the hemoglobin content and concentration of individual erythroblasts at various stages of maturation in the bone marrow by scanning microspectrophotometry. In contrast to normal erythroblasts, those from hematopoietic dysplasia had decreased hemoglobin content and decreased hemoglobin concentration at late stages of maturation. This observation, together with the observed near-normal hemoglobin content and concentration of circulating red cells in this disorder, suggests that polychromatophilic erythroblasts with decreased hemoglobin content fail to complete normal maturation. The abnormalities in hemoglobin content observed in vivo in hematopoietic dysplasia could be reproduced in the in vitro cultures of erythroid progenitors of bone marrow cells from the patients.

Anemia, Hypochromic↗
PubMed1978

[DNA concentration in cells of the glandular epithelium of the endometrium during the menstrual bleeding phase].

DNA content in the endometrial gland cells (9 women of fertile age) was studied during menstruation by microspectrophotometry. It was shown that DNA content (mainly 2n) remained unchanged during different days of menstruation, both during the desquamation (the 1st--2nd days of the cycle), and during the regeneration stage (the 3rd--4th days). Along with this the mitotic activity in the glandular epithelium was absent completely (36 samples of endometrium).

Cell Biology↗
PubMed1983

Nuclear DNA content of normal, neoplastic and "wart-affected" cervical biopsies.

Cellular imprints from 30 colposcopic biopsies were analyzed for their intranuclear DNA content using Feulgen staining and microspectrophotometry. Biopsies from ten areas of normal epithelium were compared with those from ten cervical intraepithelial neoplasias (CIN) and ten noncondylomatous warty atypias (NCWA). The normal biopsy prints showed an expected diploid-tetraploid stem cell line. Warty atypias and CIN could be distinguished by their aneuploid Feulgen-stained cells and the polypoid densitometry pattern of the warty atypias. The significance of these findings in relation to cervical neoplasia is discussed.

Biopsy↗
PubMed1981

[Changes in the activity of oxidative enzymes in thymus cells of CBA mice during carcinogenesis induced by simian adenovirus SA7(C8)].

Microspectrophotometry was used to study the activity of oxidative enzymes in the cortical and medullar regions of the thymus, in epithelial stromal cells of CBA mice at varying time of postnatal development and during induced virus cancerogenesis. It was shown that in the thymus of control animals, the activity of NAD-, NADP-diaphorases and beta OBDH reached maximum on the 30th day of postnatal development. The animals exposed to virus manifested a distinct lowering of the activity of the enzymes even in the latent period of cancerogenesis. Variations of the activity of the test enzymes during postnatal development of control animals and at varying time of cancerogenesis appear to be related to functional potencies of the thymus.

Adenoviridae↗
PubMed1981

[Changes in the structural heterogeneity of surviving nerve cells].

Heterogeneity in distribution of the dry substance mass (protein) in normal and reactively altered isolated neurons has been studied in vital investigations by means of interference microscopy and microspectrophotometry. It has been demonstrated that at a reactive reconstruction neuroplasmic substances undergo rearrangement, resulting in increased heterogeneity. In peripheral juxtamembranous parts neuroplasmic colloids are divided separating the hydrated zone with a low content of protein and forming made that an increasing adhesion of the juxtamembranous proteins could result in their aggregation with protein complexes of the transmembranous ionic canals, that affects the specific electrogencic function of the neuron.

Animals↗
PubMed1978

Retinal organisation in goldeye and mooneye (Teleostei: hiodontidae).

This paper presents the results of a comparative investigation of the retinas of two Hiodontids, the goldeye (Hiodon alosoides) and the Mooneye (H. tergisus) employing light and electron microscopy, cell isolation techniques as well as microspectrophotometry. Contrary to the observations of previous workers these species possess a duplex retina. The photoreceptors are bundled in groups of 20 rods and 20 cones. They exhibit features which have hitherto not been observed in vertebrates. These are a) an ellipsoid divided in two parts by the myoid: b) tubules in cone outer segments and, c) large "lateral sacs" (accessory outer segments). Cones are immobile but the rods and epithelial pigment are capable of movement (retinomotor responses). The prominent reflecting layer consists of cuboid and rod-like crystals composed of uric acid. The inner layers are made up of three tiers of large horizontal cells, one of amacrine cells and scarce bipolar and ganglion cells. Bundle density is 1 700 per sq. mm. Roughly, one receptor bundle projects onto one bipolar and one ganglion cell suggesting that each bundle acts as a functional unit. The visual pigment of the mooneye absorbs maximally at 535 +/- 2 nm, and is based on vitamin A2 (porphyropsin). We suggest that all non deep-sea fishes with bundled receptors have duplex retinas and the adaptive mechanisms for vision in turbid waters are based on different morphological means as illustrated by the comparison with Stizostedion.

Adaptation, Ocular↗
PubMed1978

Microspectrophotometric studies on the visual pigment in the intact retina of the goldfish, Carassius auratus (Linn.).

The visual pigments in intact retinas of the common goldfish were examined by microspectrophotometry. Difference spectra free of photoproduct contamination had absorbance maxima at lambda527 nm +/- 2 nm. The average pigment density, about 0.32, was almost invariant with regard to retinal location and specimen size. Traces of a photoproduct absorbing maximally at lambda480-490 nm were found. The normalized "absorbance" curve deviated from standard templates. It was suggested that this was an effect of cross-coupling of energy and among photoreceptors. Finally, known action spectra show a red shift relative to the absorbance spectra measured.

Animals↗
PubMed1981

Nuclear DNA study of vulvar intraepithelial and invasive squamous neoplasms.

In this study, 59 vulvar intraepithelial squamous neoplasms (8 atypia and 51 carcinoma in situ) and 33 invasive squamous carcinomas were analyzed for their nuclear DNA content using Feulgen microspectrophotometry. Four cases of atypia had a polyploid DNA distribution. The remaining 4 cases of atypia and all cases of carcinoma in situ had an aneuploid pattern, and nearly two thirds of these had high ploidy stem cells (greater than 3N). This is in contrast to the low ploidy stem cells (less than 3N) seen in 70% of the invasive carcinomas and in 82% of the intraepithelial neoplasms in the vicinity of invasive carcinomas. This observation suggests that not all vulvar intraepithelial neoplasms have the same propensity to become invasive. Invasive carcinomas of comparable size and depth of invasion with low ploidy stem cells had a higher frequency of lymph node metastasis than those having high ploidy stem cells. The significance of nuclear DNA findings related to gynecologic neoplasms is discussed.

Aneuploidy↗
PubMed1994

Quantitative cytophotometric and autoradiographic analysis of the cell cycle kinetics during growth and development of the plasmodium in the myxomycete Didymium iridis.

Nuclear changes in basic protein, RNA, and DNA in plasmodia of Didymium iridia at 4, 8, and 12 days during their progression through the growth cycle prior to sporulation were analysed. Relative determinations of basic protein and RNA were made using naphthol yellow-S/azure B in conjunction with absorption microspectrophotometry. DNA was quantified by quantitative cytophotometric measurements of Feulgen-stained nuclei. Autoradiographic techniques provided information on periods of DNA synthesis. A net decrease in protein and RNA to a point of stabilization was shown which correlated with increased age of the organism and decreased nutrient supply in the plasmodia. The 4C DNA content of the 4 day plasmodia indicated rapid growth and high metabolic activity while in the 8 day plasmodia a 2C DNA was observed consistent with the presence of a G1 period of some duration.

Cell Cycle↗
PubMed1994

Significant fiber evidence recovered from the clothing of a homicide victim after exposure to the elements for twenty-nine days.

An adhesive tape lint removal roller was used to isolate fibers from a homicide victim's clothing that had been exposed to the elements for twenty-nine days. Comparison microscopy, microspectrophotometry, and infrared analysis were used to compare recovered fibers to known fibers obtained from the suspect's shirt and the car in which it was believed the homicide occurred. Fibers recovered from the victim's clothing included specimens that were indistinguishable from fibers constituting the suspect's shirt, and others that were indistinguishable from the three distinct types of fibers comprising the upholstery, carpeting, and trunk liner of the car. The distribution of fibers on the various garments helped corroborate the crime scenario.

Adolescent↗
PubMed1994

Disease of the left ventricle in pulmonary atresia with intact ventricular septum. The limiting factor for long-lasting successful surgical intervention?

Eight hearts with pulmonary atresia with intact ventricular septum were studied grossly and microscopically. The right ventricle was composed of inlet, infundibular, and trabecular portions in two hearts, without trabecular portions in three hearts, and consisted of an inlet part only in another three hearts. Pulmonary atresia was classified as membranous in two hearts; the other six hearts had muscular atresia. The left ventricle showed a range of abnormalities, albeit mostly discrete. A mitral valve with short tendinous chords was present in four hearts; one of these had a cleft mitral valve. All hearts (except the heart of a 1-day-old neonate) had a prominent subaortic septal bulge. All hearts had left ventricular hypertrophy, which exceeded twice the standard deviation of normal in two patients. None of the hearts had histologic features of hypertrophic cardiomyopathy. The density of intramyocardial coronary arteries was normal in each patient, but medial thickening (20 to 100 microns diameter arteries) had occurred in four patients. Signs of acute myocardial ischemia (hydropic cell swelling) were present in all; one heart (the oldest case of 6 months) contained areas of replacement fibrosis and calcifications indicative of previous infarction. Quantification of the volume density of endomysial (interfiber) collagen (Picrosirius red microspectrophotometry) showed high levels in all, within the range of normal in five patients, but exceeding twice the standard deviation of normal in three patients. In all cases the values obtained in the subendocardial layers were higher than those obtained subepicardially. The observations show that the left ventricle in hearts with pulmonary atresia with intact ventricular septum contains abnormalities that may render the left ventricle less capable to cope with a volume load. The high values of endomysial (interfiber) collagen suggest chronic ischemia in relation to left ventricular hypertrophy as the main mechanism involved. Therefore, as a late consequence, the left ventricle could be the limiting factor for long-lasting successful surgical intervention.

Coronary Vessels↗
PubMed1993

[Prognostic significance of nuclear DNA content of colonic carcinoma].

In this study nuclear DNA content of the cancer tissue was analysed retrospectively by microspectrophotometry in two groups of colonic cancer patients: Group I, 19 cases who died within two years after radical surgery and Group II, 24 cases with a survival of more than 5 years. The other clinicopathological findings including location of tumor, grade of histological differentiation, depth of invasion, lymph vessel and venous invasion, lymph node metastasis, histological stage, and preoperative CEA level were similar between the groups. The DNA histograms were classified into two types as following: Type I: in which the ratio of over 3C cells was less than 15% type II: in which the ratio of over 3C cells was 15% or more. It was found that the percentage of type I DNA histogram was significantly higher in the long-term-survivors, while type II histogram was predominant in the short-term-survivors (P < 0.05). These results suggest that the nuclear DNA content of the cancer cells may bone of prognostic value in colonic carcinoma.

Adenocarcinoma↗