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Morphological Criteria (morphological + criterion)
Selected AbstractsA novel assay based on fluorescence microscopy and image processing for determining phenotypic distributions of rod-shaped bacteriaBIOTECHNOLOGY & BIOENGINEERING, Issue 2 2009Konstantinos Spetsieris Abstract Cell population balance (CPB) models can account for the phenotypic heterogeneity that characterizes isogenic cell populations. To utilize the predictive power of these models, however, we must determine the single-cell reaction and division rates as well as the partition probability density function of the cell population. These functions can be obtained through the Collins,Richmond inverse CPB modeling methodology, if we know the phenotypic distributions of (a) the overall cell population, (b) the dividing cell subpopulation, and (c) the newborn cell subpopulation. This study presents the development of a novel assay that combines fluorescence microscopy and image processing to determine these distributions. The method is generally applicable to rod-shaped cells dividing through the formation of a characteristic constriction. Morphological criteria were developed for the automatic identification of dividing cells and validated through direct comparison with manually obtained measurements. The newborn cell subpopulation was obtained from the corresponding dividing cell subpopulation by collecting information from the two compartments separated by the constriction. The method was applied to E. coli cells carrying the genetic toggle network with a green fluorescent marker. Our measurements for the overall cell population were in excellent agreement with the distributions obtained via flow cytometry. The new assay constitutes a powerful tool that can be used in conjunction with inverse CPB modeling to rigorously quantify single-cell behavior from data collected from highly heterogeneous cell populations. Biotechnol. Bioeng. 2009;102: 598,615. © 2008 Wiley Periodicals, Inc. [source] The significance of the diagnosis of atypia in breast fine-needle aspirationDIAGNOSTIC CYTOPATHOLOGY, Issue 5 2004Jennifer C. Lim M.D. Abstract The diagnosis of atypia in breast fine-needle aspiration (FNA) continues to be an area of debate in cytology practice. The aim of this study was to assess the clinical significance of this term and to evaluate potential morphological criteria, which would determine the patient's outcome. A computer-based search was carried out to retrieve breast FNAs performed between 1990 and 2000 that were diagnosed as atypical. Cases followed by surgical resection were reexamined for the presence of morphological features potentially differentiating benign and malignant lesions. Out of 1,568 breast FNAs, there were 64 cases (4%) with a diagnosis of atypia. Thirty-eight cases had surgical follow-up material that revealed malignancy in 14 cases (37%) and benign lesions in 24 cases (63%). The benign diagnostic categories included fibrocystic change (12/24), fibroadenoma (3/24), tubular adenoma (2/24), and nonspecific findings (7/24). The malignant diagnoses included ductal carcinoma (9/14), lobular carcinoma (3/14), ductal carcinoma in situ (DCIS; 1/14), and tubular carcinoma (1/14). The evaluation of cytological criteria used to differentiate benign from malignant lesions (i.e., cellularity, loss of cohesion, myoepithelial cells, nuclear enlargement, nuclear overlap, prominent nucleoli) revealed significant overlap between benign and malignant cases, particularly in cases of fibroadenoma, tubular adenoma, and proliferative breast disease. The surgical follow-up of four hypocellular cases revealed lobular carcinoma in two cases and ductal carcinoma in the remaining two cases. Our study confirmed that the diagnosis of atypia is clinically significant because it is associated with a high probability of malignancy. No morphological criterion is able to reliably differentiate benign and malignant lesions in cases diagnosed with atypia. Diagnosis of atypia is particularly significant in hypocellular cases. We recommended that breast FNAs with a diagnosis of atypia be evaluated further histologically. Diagn. Cytopathol. 2004;31:285,288. © 2004 Wiley-Liss, Inc. [source] BIODIVERSITY RESEARCH: Genetic diversity in two introduced biofouling amphipods (Ampithoe valida & Jassa marmorata) along the Pacific North American coast: investigation into molecular identification and cryptic diversityDIVERSITY AND DISTRIBUTIONS, Issue 5 2010Erik M. Pilgrim Abstract Aim, We investigated patterns of genetic diversity among invasive populations of Ampithoe valida and Jassa marmorata from the Pacific North American coast to assess the accuracy of morphological identification and determine whether or not cryptic diversity and multiple introductions contribute to the contemporary distribution of these species in the region. Location, Native range: Atlantic North American coast; Invaded range: Pacific North American coast. Methods, We assessed indices of genetic diversity based on DNA sequence data from the mitochondrial cytochrome c oxidase subunit I (COI) gene, determined the distribution of COI haplotypes among populations in both the invasive and putative native ranges of A. valida and J. marmorata and reconstructed phylogenetic relationships among COI haplotypes using both maximum parsimony and Bayesian approaches. Results, Phylogenetic inference indicates that inaccurate species-level identifications by morphological criteria are common among Jassa specimens. In addition, our data reveal the presence of three well supported but previously unrecognized clades of A. valida among specimens in the north-eastern Pacific. Different species of Jassa and different genetic lineages of Ampithoe exhibit striking disparity in geographic distribution across the region as well as substantial differences in genetic diversity indices. Main conclusions, Molecular genetic methods greatly improve the accuracy and resolution of identifications for invasive benthic marine amphipods at the species level and below. Our data suggest that multiple cryptic introductions of Ampithoe have occurred in the north-eastern Pacific and highlight uncertainty regarding the origin and invasion histories of both Jassa and Ampithoe species. Additional morphological and genetic analyses are necessary to clarify the taxonomy and native biogeography of both amphipod genera. [source] Morphological variations in the pre-imaginal development of the ponerine ant Diacamma ceylonenseACTA ZOOLOGICA, Issue 1 2005Sébastien Baratte Abstract In the present paper, the larval development of the queenless ponerine ant Diacamma ceylonense is studied. Four instars were identified on the basis of cuticular processes , tubercles and spinules , which show discontinuous variation during growth and provide precise and reliable external morphological criteria for instar discrimination. In the first three instars, the larva possesses a striking proboscis, which disappears between the third and fourth instars. Larval weight increased around 50-fold in the 21 days of larval life between eclosion and pupation (mean weight for first instar = 0.37 mg; for fourth instar = 20 mg). In addition, the morphology of the gemmae, structures resembling vestigial wings in workers, is described in nymphae. [source] 4-nonylphenol-induced toxicity and apoptosis in Hydra attenuataENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2005Sophie Pachura Abstract Effects of 4-nonylphenol (4-NP) onthe morphology and survival of the cnidarian Hydra attenuata were studied under acute exposure conditions. The lethal concentration value inducing 50% mortality after 96 h was 97.5 ± 20 ,g/L, whereas the lethal concentration value inducing 10% mortality after 96 h was 64 ± 25.5 ,g/L. The no-observed-effect concentration based on morphological criteria was less than 25 ,g/L. Hydra was one of the most sensitive freshwater invertebrate species behind the amphipod Hyalella azteca. Toxicity effects appeared rapidly and did not evolve substantially between 24 and 96 h of exposure. Induction of apoptosis was registered during the first hour of exposure to 4-NP at lethal concentrations, indicating rapid effects of the chemical. Abnormal increase of apoptosis may explain the acute toxicity of 4-NP in hydra. Results show that hydra viability is affected in the short term at 4-NP concentrations normally found in contaminated sites, but not at those concentrations reflecting lower levels of environmental contamination. [source] Morphological classification and definition of benign, preneoplastic and non-invasive neoplastic lesions of the urinary bladderHISTOPATHOLOGY, Issue 6 2008R Montironi The morphological classification used in this essay has been based on the most recent World Health Organization (WHO) classification of tumours of the urinary system (i.e. 2004 WHO classification). It includes epithelial abnormalities and metaplasias as well as dysplasias and carcinomas in situ. The lesions are broadly subdivided into two major groups: benign, preneoplastic and non-invasive neoplastic lesions of the urothelium; and benign, preneoplastic and non-invasive neoplastic bladder lesions other than urothelial. Each of these lesions is defined with strict morphological criteria to provide more accurate information to urologists and oncologists in managing patients. There is still debate in the literature as to whether the 2004 WHO system should be the only one to be used and whether the 1973 WHO system should be abandoned. [source] Mitotic counting in surgical pathology: sampling bias, heterogeneity and statistical uncertaintyHISTOPATHOLOGY, Issue 1 2001F B J M Thunnissen Mitotic counting in surgical pathology: sampling bias, heterogeneity and statistical uncertainty Although several articles on the methodological aspects of mitotic counting have been published, the effects of macroscopic sampling and tumour heterogeneity have not been discussed in any detail. In this review the essential elements for a standardized mitotic counting protocol are described, including microscopic calibration, specific morphological criteria, macroscopic selection, counting procedure, effect of biological variation, threshold, and the setting of an area of uncertainty (,grey area'). We propose that the use of a standard area for mitotic quantification and of a grey area in mitotic counting protocols will facilitate the application of mitotic counting in diagnostic and prognostic pathology. [source] Quantitation of cytological parameters of malignant lymphocytes using computerized image analysisINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 4 2008S. A. HAMID JAHANMEHR Summary Computerized image analysis may add to morphological evaluation by turning qualitative data into quantitative values. In this study, image analysis program was used to quantitate cytological parameters of lymphocytes in B-cell lymphoproliferative disorders. Chronic lymphocytic leukemia (CLL), mantle cell lymphoma (MCL) and B-cell prolymphocytic leukemia (B-PLL) were selected to represent typically small, medium, and large-sized lymphocytes, respectively. Image analysis was performed to determine the morphological parameters. A set of measurements was generated for quantitation of total cell area, cell diameter, cytoplasm area, nuclear area, nuclear/cell ratio, and nuclear density. The quantitated parameters substantiated morphological characteristics of the tumor cells. Comparative assessments demonstrated that CLL, MCL, and PLL can be differentiated by the quantitative descriptors. The results from image analysis may assist in defining morphological criteria and in developing quantitative cell morphology. [source] The application of ancient DNA analysis to identify neolithic caprinae: a case study from the site of Hatoula, IsraelINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 3 2003Gila Kahila Bar-Gal Abstract The evidence for wild sheep (Ovis orientalis) in archaeological sites from the southern Levant is examined through the application of ancient DNA analysis to specimens from the Pre-Pottery Neolithic A (8300,7500 uncal. BC) site of Hatoula, Israel. The results indicate that at least one of the bones from this site, previously identified as sheep, is in fact goat. To date this is the earliest faunal sample to have yielded DNA in the region. This study highlights the problems in applying morphological criteria to distinguish between caprine species, and illustrates how ancient DNA analysis can serve as a powerful tool in resolving questions of species attribution. Copyright © 2003 John Wiley & Sons, Ltd. [source] Reproductive status in females of the Brazilian catfish, Pseudoplatystoma fasciatum reared in cagesJOURNAL OF APPLIED ICHTHYOLOGY, Issue 5 2010E. Romagosa Summary The distinctive morphological features of the ovaries the ,cachara', Pseudoplatystoma fasciatum were characterized macroscopically, and by histology, when reared in cages, from March 2005 to February 2006. Forty eight females (mean total weight = 2.7 kg, mean standard length = 65.1 cm) were allocated to four cages of 2.7 m3 (20 fish/cage) which were installed in four 600 m2 ponds, located at the IP, Pariquera-Açu, Săo Paulo, Brazil. The monthly, samples were fixed in 4%-buffered formalin before preparation for histological examination, ovaries were removed and weighted. The gonadosomatic index (GSI) was calculated as = 100 × weight ovaries/total fish weight. The ovaries are the cystovarian type and macroscopically, were established three stages of ovarian maturation: Resting, developing Maturation (initial, intermediate, final) and Regression (initial, intermediate, final). Based on morphological criteria of those ovaries, the oocyte development has been divided into distinct stages: (i) oocyte growth (vitellogenesis); (ii) oocyte maturation, along which it goes through different phases of development, before (iii) ovulation and, (iv) spawning. When the P. fasciatum were kept in confinement and not induced to breed occurs fail to attain final oocyte maturation, start the process of degeneration. Consequently, the weight started to decline and 45% of the ovaries showed atresia of vitellogenic follicles. This was considered indicative of a recent cessation of the reproductive activity. Such failure could have been caused by stress of the monthly sampling involving a certain degree of disturbance, and perhaps also by the existence of stressors while in captivity. The synchronous ovary contained oocytes in an unique stage of development and had potential to perform total spawning up to one time a year, with the period reproductive beginning in the end of November to the beginning of February, coinciding with the highest water temperatures in the experimental cages (29.0,31.5°C) and the increase of mean values of GSI. During the regression phase, residual oocytes could be observed together with decrease of the mean values of GSI and, the temperatures. [source] Nuclear changes in necrotic HL-60 cellsJOURNAL OF CELLULAR BIOCHEMISTRY, Issue S36 2001Roberta Bortul Abstract Cell death in eukaryotes can occur by either apoptosis or necrosis. Apoptosis is characterized by well-defined nuclear changes which are thought to be the consequence of both proteolysis and DNA fragmentation. On the other hand, the nuclear modifications that occur during necrosis are largely less known. Here, we have investigated whether or not nuclear modifications occur during ethanol-induced necrotic cell death of HL-60 cells. By means of immunofluorescence staining, we demonstrate that the patterns given by antibodies directed against some nuclear proteins (lamin B1, NuMA, topoisomerase II,, SC-35, B23/nucleophosmin) changed in necrotic cells. The changes in the spatial distribution of NuMA strongly resembled those described to occur during apoptosis. On the contrary, the fluorescent pattern characteristic for other nuclear proteins (C23/nucleolin, UBF, fibrillarin, RNA polymerase I) did not change during necrosis. By immunoblotting analysis, we observed that some nuclear proteins (SAF-A, SATB1, NuMA) were cleaved during necrosis, and in the case of SATB1, the apoptotic signature fragment of 70 kDa was also present to the same extent in necrotic samples. Caspase inhibitors did not prevent proteolytic cleavage of the aforementioned polypeptides during necrosis, while they were effective if apoptosis was induced. In contrast, lamin B1 and topoisomerase II, were uncleaved in necrotic cells, whereas they were proteolyzed during apoptosis. Transmission electron microscopy analysis revealed that slight morphological changes were present in the nuclear matrix fraction prepared from necrotic cells. However, these modifications (mainly consisting of a rarefaction of the inner fibrogranular network) were not as striking as those we have previously described in apoptotic HL-60 cells. Taken together, our results indicate that during necrosis marked biochemical and morphological changes do occur at the nuclear level. These alterations are quite distinct from those known to take place during apoptosis. Our results identify additional biochemical and morphological criteria that could be used to discriminate between the two types of cell death. J. Cell. Biochem. Suppl. 36: 19,31, 2001. © 2001 Wiley-Liss, Inc. [source] Micro- and macroscopic characteristics to stage gonadal maturation of female Baltic codJOURNAL OF FISH BIOLOGY, Issue 2 2003J. Tomkiewicz A set of histological characteristics to judge ovarian development was established and used to elaborate morphological criteria of 10 maturity stages of Baltic cod Gadus morhua sampled throughout the annual cycle to represent different macroscopic maturity stages. The applied characteristics confirmed most stages of the macroscopic scale, but the separation of late immature and resting mature females remained imprecise. Atretic vitellogenic oocytes or encapsulated residual eggs identified the resting condition morphologically, but not all ovaries with visible signs of previous spawning showed such features. One ovarian stage that was previously classified as ,ripening' was changed to ,spawning', owing to the prevalence of hydrated eggs and empty follicles. Ovaries with malfunctions were defined by a separate stage. Macroscopic criteria were revised by comparing the gross anatomy of ovaries with their histology. Female length and gonado-somatic index supported stage definitions, but substantial variation in Fulton's condition factor and the hepato-somatic index rendered these of little use for this purpose. The time of sampling influenced staging accuracy. A female spawner probability function based on the proportion of ripening and ripe specimens in early spring seems to be the most appropriate method to estimate spawner biomass and reproductive potential. [source] Can Renal Acute Tubular Necrosis Be Differentiated from Autolysis at Autopsy?,JOURNAL OF FORENSIC SCIENCES, Issue 2 2009Linda Kocovski B.Sc. Abstract:, We investigate the morphological characteristics that may differentiate between ischemic acute tubular necrosis (ATN) and autolysis in postmortem samples. Renal tissue from 57 postmortem cases with an antemortem diagnosis of ATN and 57 age-/sex-matched control cases were examined for 10 morphological characteristics: epithelial proliferation (Ki-67 immunoperoxidase positivity), fibrin thrombi, tubular epithelial whorls, mitoses, casts, autolysis, tubulorrhexis, epithelial flattening, interstitial inflammation, and interstitial expansion. Tubular epithelial whorls were found in 16 ATN cases and were absent in controls. These findings suggest that specific morphological criteria may distinguish ischemic ATN from autolysis. Diagnoses of ATN may be confirmed using these combined criteria as contributing to cause of death and/or to ascertain previously undiagnosed cases of ATN postmortem. [source] Circulating soluble cytochrome c in liver disease as a marker of apoptosisJOURNAL OF INTERNAL MEDICINE, Issue 2 2003Z. Ben-Ari Abstract. Ben-Ari Z, Schmilovotz-Weiss H, Belinki A, Pappo O, Sulkes J, Neuman MG, Kaganovsky E, Kfir B, Tur-Kaspa R, Klein T (Beilinson and Golda Campuses, Rabin Medical Center, Petah Tiqva and Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel, and In Vitro Toxicology Laboratory, Sunnybrook Women's College, Toronto, Canada) Circulating soluble cytochrome c in liver disease as a marker of apoptosis. J Intern Med 2003; 254: 168,175. Objectives. To measure levels of soluble cytochrome c, a clinical marker of apoptosis in patients with liver disease; determine whether soluble cytochrome c is derived from the liver; and correlate soluble cytochrome c level with histology and disease activity. Design. Laboratory research study with comparison group. Setting. Liver Institute, at the Rabin Medical Center, Israel, and In Vitro Toxicology Laboratory, Canada. Subjects. A total of 108 patients with liver disease and 30 healthy controls. Interventions. Paired hepatic and portal vein samples were taken via the transjugular vein in patients after liver biopsy and transjugular intrahepatic portacaval shunt, and bile from patients with external biliary drainage. Soluble cytochrome c was measured with an enzyme-linked immunosorbent assay in peripheral blood. Apoptotic cells in liver tissue were identified by morphological criteria and quantitated with the dUTP nick-end-labelling (TUNEL) assay. Main outcome measures. Soluble cytochrome c level by type of liver disease by clinical and histological findings. Results. Soluble cytochrome c concentration (mean 187.1 ± 219.5 ng mL,1) was significantly higher in patients with liver disease than in controls (39.8 ± 35.1 ng mL,1; P = 0.0001), with highest levels in the primary sclerosing cholangitis group (mean 1041.0 ± 2844.8 ng mL,1; P = 0.001). Cytochrome c levels were correlated with serum bilirubin, alkaline phosphatase, creatinine levels, necroinflammatory score and apoptotic index, but not with serum alanine aminotransferase and synthetic liver function tests. In the 16 paired samples, soluble cytochrome c level was higher in the hepatic (mean 267.9 ± 297.0 ng mL,1) than the portal vein (mean 169.2 ± 143.3 ng mL,1), and it was highly detectable in bile (mean 2288.0 ±4596.0 ng mL,1) (P = 0.001). Untreated patients with chronic viral hepatitis (B and C) had significantly higher levels (mean 282.8 ±304.3 ng mL,1) than treated patients (77.9 ± 35.8 ng mL,1; P = 0.001). Conclusions. Soluble cytochrome c levels are increased in different types of liver disease. Soluble cytochrome c is probably derived from the liver and secreted into the bile. Levels correlate with the apoptotic index and are affected by antiviral treatment. Soluble cytochrome c may serve as a serum marker of apoptosis. [source] MOLECULAR AND PHYLOGENETIC CHARACTERIZATION OF PHORMIDIUM SPECIES (CYANOPROKARYOTA) USING THE CPCB-IGS-CPCA LOCUS,JOURNAL OF PHYCOLOGY, Issue 1 2005Ivanka Teneva The accurate determination of species of Cyanoprokaryota/Cyanophyceae has many important applications. These include the assessment of risk with regard to blooms in water reservoirs as well as the identification of species capable of producing valuable bioactive compounds. Commonly, Cyanoprokaryota are classified based on their morphology. However, morphological criteria are not always reliable because they may change, for example, due to environmental factors. Thus, genetic and molecular analyses are a promising additional approach, but their application has so far been limited to relatively few genera. In light of this, we present here the first characterization of species and strains of the genus Phormidium Kütz. based on the cpcB-IGS-cpcA locus of the phycocyanin operon. In phylogenetic analyses using deduced amino acid sequences of the cpcB-cpcA regions, Phormidium was found to be polyphyletic. This analysis appeared to be dominated by the cpcB region, which is characterized by a relatively high percentage of informative substitutions. The percentage of variable positions within the cpcB-IGS-cpcA locus overall was 16.5%, thereby indicating a level of divergence remarkably higher than that reported for Nodularia and Arthrospira in previous studies relying on cpcB-IGS-cpcA. Further, alignment of informative nucleotide substitutions in the cpcB-IGS-cpcA sequences revealed a mosaic distribution, which may be indicative of genetic recombination events. Finally, the length and sequences of the IGS region alone proved useful as markers to differentiate the cyanobacterial genus Phormidium. However, whether the IGS region per se is sufficiently discriminatory to differentiate between Phormidium species or even strains requires further investigation using newly identified Phormidium sequence data. [source] Effects of Betamethasone Treatment on Central Myelination in Fetal Sheep: An Electron Microscopical StudyANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2 2008C. Raschke Summary The long-term effect of betamethasone on the myelination of commissural and associational fibres was investigated in fetal sheep. We studied the corpus callosum and subcortical white matter by electron microscopy. Axons were subdivided into classes according to their axonal diameter: class I: ,0.65 ,m; class II: 0.66,0.84 ,m; class III: ,0.85 ,m. Under control conditions, the different functions of the white matter tracts examined were reflected by three morphological criteria: (1) there was a diverse percentage of axonal classes in the investigated areas. In corpus callosum the axons of class II predominate (47.1%). In the subcortical white matter, class I axons with small diameter are in majority (40.8%). (2) In the subcortical white matter more axons are present, with especially large diameter and hence of axonal class III. (3) The axons of subcortical white matter have thicker myelin sheaths than those of the corpus callosum. Betamethasone administration caused a significant decrease of class II axons in the corpus callosum (36.9%). In corpus callosum, axons of all classes present thicker myelin sheaths. Betamethasone administration resulted in a change in the formation of the myelin sheath in the commissural fibres of the corpus callosum but not in the associational fibres of the subcortical white matter. This could be the morphological correlate to behavioral and cognitive changes known to occur in humans after prenatal glucocorticoid treatment. [source] Deregulation of cell-death pathways as the cornerstone of skin diseasesCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 6 2010N. Zutterman Summary Deregulation of cell-death pathways plays a key role in the pathogenesis of various skin diseases. The different types of cell death are mainly defined by morphological criteria, and include apoptosis, autophagic cell death, and necrosis. The process of apoptosis is well characterized at the molecular level and involves the activation of two main pathways, the intrinsic and extrinsic pathways, converging into the execution of apoptosis by intracellular cysteine proteases, called caspases. The relevance and implication of these apoptotic pathways in the pathophysiology of skin diseases, such as toxic epidermal necrolysis, graft-versus-host disease and skin cancer, has been extensively studied. The role of autophagic cell death in progression of skin tumours and response to cytotoxic drugs is only beginning to be elucidated. [source] | ||||||||||||||||