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At least 19 recordsLinked to original sources
PubMed1980

Stoichiometry of wheat germ agglutinin as a morphology controlling agent and as a morphology controlling agent and as a morphology protective agent for the human erythrocyte.

The lectin wheat germ agglutinin (WGA) is an unusually effective agent in controlling both the forward and reverse reactions of the reversible morphology conversion discocyte in equilibrium with echinocyte for the human erythrocyte. Under conditions severe enough to drive the reactions to completion in either direction without the lectin, WGA is able to stabilize both these morphologies and to fully prevent conversion of either morphology. The lectin can quantitatively block both reactions. The ability of WGA to carry out these functions has no obvious rate limitation. Its effectiveness depends mainly on its binding stoichiometry, particularly toward the transmembrane glycoprotein, glycophorin. The critical binding stoichiometries for both the lectin and the echinocytic agent were determined in relation to the binding isotherms using 125I-labeled WGA and 35S-labeled dodecyl sulfate. There appear to be two principal stoichiometries for WGA binding that are important in its control of erythrocyte morphology. The first stoichiometry marks the threshold of obvious protection of the discocyte against strong echinocytic agents such as detergents and, likely, is simply a 1:1 stoichiometry of WGA: glycophorin, assuming currently recognized values of 3--5 x 10(5) copies of glycophorin per cell. The second important stoichiometry, whereby the cell's morphology is protected against extremely severe stress, involves binding of approximately 4--5 WGA molecules per glycophorin. The controls that WGA exerts can be instantly abolished by added N-acetylglucosamine. However, N-acetylglucosamine ligands on the erythrocyte are of less importance than membrane neuraminic acid residues in enabling WGA to control the cell's morphology, as is shown by comparing intact cells with completely desialated cells. WGA can also be used to produce elliptocytes in vitro, but it does this at levels approaching monolayer coverage of the cell with WGA.

Acetylglucosamine↗
PubMed1953

Morphologic variation in pneumococcus. I. An analysis of the bases for morphologic variation in pneumococcus and description of a hitherto undefined morphologic variant.

The problem of morphologic variation in pneumococcus has been reviewed and the desirability of studying such variation through an examination of bacterial cells rather than of bacterial colonies has been pointed out. To further this objective, a new terminology to describe the morphologic variants of pneumococcus, potentially applicable to other bacterial species, has been proposed. A hitherto undefined morphologic variant of pneumococcus, the filamentous capsulated (fil+ S+) variant, has been defined and its relationship to the three previously recognized non-filamentous capsulated (fil- S+), nonfilamentous non-capsulated (fil- S-), and filamentous non-capsulated (fil+ S-) variants has been presented.

Streptococcus pneumoniae↗
PubMed1989

Quantitative and morphological studies of the bones by mathematical morphology--theory and practice of mathematical morphology.

To quantitatively analyze internal bone structures, trabecular bones were quantitatively studied through the application of mathematical morphology. Mathematical morphology considers the shape of the analyze objects and utilizes image processing theory in an approach that is extremely effective on for studying the complex shapes of trabecular bones. This paper describes quantitative studies made of trabecular bone density and width, trabecular specific length per unit area, and trabecular bone orientation.

Bone Density↗
PubMed1991

Evaluation of human sperm morphology using strict criteria after Diff-Quik staining: correlation of morphology with fertilization in vitro.

New, very strict criteria were used after Diff-Quik staining for evaluating sperm morphology. The results of morphology scoring were correlated with the fertilization rate in vitro. Semen samples from 64 men participating in an in-vitro fertilization programme were used for this study. All men had to have a sperm concentration of greater than or equal to 20 million/ml and a progressive motility of greater than 30%. The morphology evaluation using strict criteria was performed on the same aliquot of semen as that used for in-vitro insemination. If strict criteria showed that normal morphology was less than or equal to 4%, the fertilization rate per oocyte was 23%. If normal morphology was greater than or equal to 11%, 77% fertilization occurred. For proportions of normal morphology between 4 and 11%, the fertilization rate per oocyte was 59% (P less than 0.000001). Among all these morphology groups, classical semen parameters, such as the mean volume, the mean concentration and the mean motility, did not differ significantly, except for the morphology evaluation using WHO criteria. The correlation with fertilization was better for morphology evaluation using strict criteria than for WHO. In conclusion, the method of evaluating sperm morphology based on very strict criteria allows a more accurate prediction of the chance of fertilization in vitro. Further studies should be done to establish the most appropriate cut-off points for severely impaired, intermediate and high fertilization rates.

Azure Stains↗
PubMed2002

Morphological types of breast cancer in family members and multiple primary tumours: is morphology genetically determined?

BACKGROUND: We conducted the present study to determine whether breast cancer morphology is genetically determined. METHODS: Using the nationwide Swedish Family Cancer Database, which includes data on 10.2 million individuals and over 25,000 morphology-specific breast cancers, we followed morphological types in familial cancers between mothers and daughters and between sisters. Additionally, we recorded morphological data in women who presented with two primary breast cancers and in those who presented with an invasive and in situ breast cancer. We used kappa statistics to examine the association between genetics and morphology. A kappa value of 0 indicates that the process is random and a value of 1 indicates that it is completely determined (i.e. genetic); values between 0.40 and 0.60 are considered to indicate a moderately determined process. RESULTS: The study sample included a total of 25,730 first and 3394 second invasive breast cancers, and 2990 in situ breast cancers. Ductal, lobular, tubuloductal and comedo were the most common invasive types. We identified 164 mother-daughter pairs with breast cancer of a defined morphology, yielding a low kappa value of 0.08. Among 100 sister pairs the kappa value was 0.002. In individuals with two primary breast cancers the kappa values were 0.22 and 0.01 for two invasive and in situ-invasive pairs, respectively. However, for a tumour with a subsequent tumour detected in the contralateral breast less than 1 year later the kappa value was 0.47. CONCLUSION: The data suggest that breast cancer morphology is not genetically determined. However, because of mixed morphologies and the overwhelming prevalence of ductal morphology, the results for rare morphologies should be interpreted with caution.

Adenocarcinoma, Mucinous↗
PubMed2003

Influence of individual sperm morphology on fertilization, embryo morphology, and pregnancy outcome of intracytoplasmic sperm injection.

OBJECTIVE: To evaluate the influence of morphology of individual spermatozoa on fertilization and pregnancy outcome. DESIGN: Retrospective analysis. SETTING: An IVF center in an institutional research environment. PATIENT(S): Fertilization and embryo quality according to individual sperm morphology were analyzed in 662 consecutive ICSI cycles. Pregnancy outcome was evaluated for these cycles and an additional 1005 consecutive ICSI cycles. INTERVENTION(S): ICSI was performed using sperm cells of ejaculated, epididymal, or testicular origin. Observation through an inverted microscope was used to prospectively classify injected sperm cells as normal or morphologically abnormal. MAIN OUTCOME MEASURE(S): Oocyte fertilization, embryo morphology, and pregnancy outcome of unmixed embryo transfers. RESULT(S): Injection of morphologically abnormal spermatozoa (irrespective of origin) resulted in a lower fertilization rate (60.7%) than did injection of morphologically normal spermatozoa (71.7%). Embryo cleavage quality did not differ between groups. Higher pregnancy and implantation rates were obtained in patients with normal sperm morphology (36.7% and 18.7%, respectively) than in those with abnormal sperm morphology (20.2% and 9.6%). CONCLUSION(S): Individual sperm morphology assessed at the moment of ICSI correlated well with fertilization outcome but did not affect embryo development. The implantation rate was lower when only embryos resulting from injection of an abnormal spermatozoon were available.

Ejaculation↗
PubMed2003

Pronuclear morphology evaluation with subsequent evaluation of embryo morphology significantly increases implantation rates.

OBJECTIVE: To elucidate the relative predictive value of implantation markers at different stages of preimplantation development. DESIGN: Correlation of pronuclear morphology with embryo morphology and implantation rates in retrospective and prospective analysis of in vitro fertilization/intracytoplasmic sperm injection (IVF-ICSI) treatment cycles. SETTING: Private infertility center. PATIENT(S): A total of 441 couples undergoing infertility treatment. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Size of pronuclei and distance between them, the number and polarization of nucleolus precursor bodies (NPB) at the one-cell stage, embryo cleavage and fragmentation rates on days 2 and 3, and pregnancy and implantation rates. RESULT(S): Polarization of the NPB in both pronuclei had a statistically significant correlation with normal membrane breakage during ICSI (40%, compared with 33% easy, and 31% difficult membrane breakage) and also with faster cleavage and lower fragmentation rates of embryos. Sixty-one percent of implanting embryos had polarization of the NPB in both pronuclei compared with 37% for all embryos. Larger distance between pronuclei and their unequal size had a statistically significant correlation with slower cleavage and inferior embryo quality. Embryo selection based on only pronuclear morphology or on only day-3 embryo morphology yielded implantation rates of 15.1% and 12.1%, respectively. Embryo selection based on sequential evaluation of both pronuclear morphology and embryo morphology on day 3 resulted in a 21.1% implantation rate. CONCLUSION(S): Polarization of NPB in both pronuclei is as reliable marker of implantation as embryo morphology on day 3. However, pronuclear morphology assessment improves embryo selection only when it is combined with embryo morphology evaluation on day 3.

Adult↗
PubMed1992

Comparative variation of morphological and molecular evolution through geologic time: 28S ribosomal RNA versus morphology in echinoids.

The comparatively good fossil record of post-Palaeozoic echinoids allows rates of morphological change to be estimated over the past 260 million years and compared with rates of molecular evolution. Parsimony analysis of morphological data, based predominantly on skeletal characteristics, and parsimony, distance and maximum likelihood analyses of molecular data, from the first 380 bases from the 5' end of the 28S rRNA molecule, for 10 species of echinoid produce congruent phylogenies. The molecular sequence chosen is demonstrably far from saturation and sister groups have divergence times ranging from about 15 to 260 Ma. Parsimony analysis allows the great majority of molecular and morphological apomorphies to be placed in one of 18 independent geological time intervals, providing a direct measure of rates of evolution for periods in the geological past. Because most molecular fixed point mutations in our sequences cannot be polarized unambiguously by outgroup comparison (making the outgroup states effectively random), distance and parsimony analyses both tend spuriously to root the echinoid tree on the longest internal branch. A topology identical to that derived from morphological data is, however, obtained using Maximum Likelihood and also parsimony analysis where outgroup rooting is restricted to more conserved regions. This is taken as the correct topology for assessing rates of evolution. Overall, both morphological and molecular changes show a moderately strong correlation with time elapsed, but a weaker correlation with one another. Statistically significant differences in evolutionary rate are found between some, but not all, pair-wise comparisons of sister lineages for both molecular and morphological data. The molecular clock rate for echinaceans is three times faster than that for cidaroids and irregular echinoids. Spearman's rank correlation test, which requires only relative magnitude of changes to be known, suggests that morphological change has a slightly better correlation with time than does molecular change, averaged over all ten species. However, when just echinaceans are considered an extremely good correlation is found between the number of molecular changes and time elapsed, whereas morphological change remains poorly correlated. Thus, molecular rates approximate to a clocklike model within restricted echinoid clades, but vary significantly between clades. Averaging results over all echinoids produces a correlation that is no better than the correlation between morphological change and time elapsed.

Animals↗
PubMed1994

Morphological errors and the representation of morphology in the lexical-semantic system.

Neuropsychological studies support the hypothesis that morphology is represented autonomously, both at the level of word meaning and at the level of word form. In output processes, morphologically organized semantic information activates lexical representations of roots and affixes, which are composed before production. In input processes, the stimulus is parsed along the morphological dimension, to access root and affix lexical representations, which in turn activate morphologically organized semantic information. Inflectional and derivational morphology are represented independently in the lexicon. Inflected words are fully decomposed; derived words are decomposed into base form+inflection. In aphasia, morphological errors in transcoding tasks always co-occur with semantic and/or phonemic errors. Morphological errors in transcoding tasks require combined damage to morphological representations in the semantic-lexical system and to sublexical conversion procedures; they co-occur with semantic errors when also root representations are damaged. The co-occurrence of morphological and phonemic errors can be accounted for by several hypotheses, but its theoretical meaning is still uncertain.

Aphasia↗
PubMed1996

Morphological processing in Italian agrammatic speakers: eight experiments in lexical morphology.

Agrammatic speech production has often been characterized as amorphology. This study of two Italian agrammatic patients shows that, with respect to inflectional morphology of simple and derived nouns, the morphological features of gender and number are almost fully preserved for one patient (MG) and only mildly disturbed in the other patient (DR). Like inflection, the use of derivational suffixation as a means of word-building is only mildly disturbed in both patients. However, they show a severe disturbance with respect to inflectional morphology of lexical compounds, which requires syntactic analysis at the word level. Moreover, they are severely impaired in the choice of the function word for the construction of prepositional compounds, syntactically generated phrases which have the status of a word. Apart from such syntax-dependent morphological and word-building operations, neither inflectional nor derivational morphology are seriously disturbed in our patients. The apparent amorphology in their spontaneous speech can thus not be explained by a disorder of morphological representations in the lexicon system perse. In another study (De Bleser and Luzzatti, 1994) we were able to show that the patients had severe problems with the implementation of morphology in specific syntactic contexts, thus pointing to a problem in morphosyntactic rather than morpholexical processing as a factor contributing to agrammatic speech production.

Adult↗
PubMed2000

Morphological priming: dissociation of phonological, semantic, and morphological factors.

Previous experiments based on a masked-priming paradigm revealed robust morphological priming effects induced by two derivational morphemes in Hebrew: the root and the verbal pattern. However, considering the special characteristics of the masked-priming paradigm, the possible contributions of phonological and/or semantic factors to these morphological effects could not be firmly assessed. In the present study, the role of these factors in morphological priming was examined, using cross-modal presentation. Experiment 1 revealed that priming between morphologically related words in Hebrew is determined by higher level linguistic characteristics and cannot be reduced to phonological overlap. Experiment 2 confirmed that morphological priming occurs in Hebrew even when primes and targets are not semantically related but, nevertheless, increases with semantic similarity. The results support the claim that morphological priming cannot be accounted for by considering semantic and phonological factors alone, and they exemplify the potential of using both masked and cross-modal priming to examine morphological processing.

Adult↗
PubMed2002

Morphological color changes in fish: regulation of pigment cell density and morphology.

Pigment cells enable fish to change their coloration. It has been recognized that fish color changes can be divided into two categories; one is a physiological color change, which is attributed to rapid motile responses of chromatophores, and the other is a morphological color change, which results from changes in the morphology and density of chromatophores. Long-term adaptation of fish to a certain background can be a general cue to morphological color changes, and has been studied from the beginning of the 19th century. Although the motile mechanism and its control in fish chromatophores are now being elucidated, it is not yet clear how chromatophores change their density and what controls morphological color changes. In recent years, chromatophores, especially melanophores, have been shown to differentiate and to die by apoptosis under the influence of factors that regulate motile responses. Those factors are likely to utilize common intracellular signaling pathways used in part to regulate both types of color changes. In this article, after briefly reviewing the history of early studies, recent findings are discussed relevant to increases or decreases in chromatophores, and changes in their morphology. Finally, morphological color changes are discussed as physiological phenomena involved in the balance between differentiation and apoptosis of chromatophores.

Adaptation, Physiological↗
PubMed1996

Acrosomal morphology as a novel criterion for male fertility diagnosis: relation with acrosin activity, morphology (strict criteria), and fertilization in vitro.

OBJECTIVE: To determine the relationships between sperm acrosin activity, sperm morphology evaluated according to strict criteria, visually observed acrosomal morphology, and IVF rates. DESIGN: Prospective analytic study. Acrosin activity was determined on all semen samples together with a standard semen analysis. Emphasis was placed on sperm morphology and especially a novel criterion viz acrosome morphology (acrosome index) as recorded with bright field microscopy. SETTING: University-based tertiary care center. PATIENTS: Thirty-three couples undergoing IVF or GIFT with two or more metaphase II ova inseminated in vitro. MAIN OUTCOME MEASURE: In vitro fertilization rates of inseminated ova. RESULTS: Strong correlations were found between acrosome index, normal sperm morphology, and IVF rates. An acrosome index cutoff value could be established at > 10% normal acrosomes for IVF rates of > or = 50% (sensitivity and specificity = 100%) and an acrosin activity cutoff value at > 18 microIU/10(6) sperm. A multiple linear regression analysis showed that the acrosome index and acrosin activity added a significant contribution to the explanation of the variation in the fertilization rates. CONCLUSIONS: A strong positive correlation was found between acrosome index and IVF rates. Although the numbers of the study are small, the results indicate that the acrosome index possibly may be regarded as an additional tool in the prediction of IVF outcome and especially may be of value in the group of men with severe teratozoospermia, i.e., < or = 4% morphologically normal spermatozoa.

Acrosin↗
PubMedDate not supplied

[On the methodology of morphology and levels of morphologic analysis].

Unjustified narrowing of the problems of morphology by merging the terms "morphology" and "anatomy" leads to stagnation in morphology. The merging of "classic" and "modern" biology will enrich both morphology and molecular biology and genetics. The latter will be able apply conceptual models of morphology to more primitive structural level of life. The possibility to apply V. A. Dogel' 's ideas on the role of oligomerization and polymerization in science to the analysis of molecular evolution has been demonstrated with the analysis of DNA content in the genomes of Chordata taken as an example. The data on DNA content do not allow both to consider lungfishes as ancestors of all Tetrapoda and develop monophyletic concept of Tetrapoda origin at the same time. The possibility of application of concepts of comparative morphology to analysis of molecular evolution has been considered.

Anatomy↗
PubMed1998

[Internal standardization of sperm morphology evaluated according to strict morphological criteria].

OBJECTIVE: To evaluate sperm morphology and find cut-off values for local andrology lab based on morphological strict criteria. To compare the results to WHO guidelines. MATERIAL AND METHODS: Strict morphological criteria were applied to 300 sperm smears stained according to the Papanicolaou method. Specific sperm defects were described in details. The results were analyzed statistically. RESULTS: The normal sperm morphology was found in 18.54% of cases, which is less than the cut-off value suggested in the WHO guidelines. The lab cut-off value aimed by the 25th percentile was 8%. CONCLUSION: Sperm morphology requires broader multi-center standardization to enable compatible exchange of morphological data and find predictive factors of sperm fertilizing potential.

Adult↗
PubMed1986

Limb morphology of domestic and wild canids: the influence of development on morphologic change.

Biomechanical hypotheses are often invoked to explain the characteristic scaling of limb proportions. Patterns of static allometry and morphologic diversity, however, may also reflect the developmental mechanisms underlying morphologic change. In this study I document the importance of such developmental influences on the evolution of limb morphology in the extremely polymorphic domestic dog and in wild canid species. I use bivariate and discriminant function analyses to compare the limb morphology of adult dogs and wild canid species. I then compare ontogenetic allometry of four dog breeds with static allometry of domestic and wild canids. Results reveal, first, that there is considerable similarity between dogs and wild canid species; many wolf-like canids cannot be distinguished from domestic dogs of equivalent size. However, all dogs are consistently separated from fox-sized, wild canids by subtle but evolutionarily significant differences in olecranon, metapodial, and scapula morphology. Second, in domestic dogs the pattern of static allometry is nearly identical to that of ontogenetic allometry. This finding can be attributed to simple heterochronic alterations of postnatal growth rates. Apparently the diversity of limb proportions among adult domestic dogs and the observed difference between dogs and wild canids are somewhat predetermined, as they directly reflect the diversity of limb proportions evident during development of the domestic dog.

Animals↗