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Results for “Morphological Characterization”

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PubMed1987

Studies on the mechanism of 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU)-induced hepatotoxicity. II. Biochemical and morphological characterization of the injury and its prevention by phenobarbital.

The present study characterizes the biochemical, morphological, and histological sites of CCNU-induced hepatotoxicity and investigates the effect of modifiers of drug metabolism on this toxicity. A single oral dose (100 mg/kg) of CCNU caused four- and ninefold increases in serum GOT and GPT respectively 48 h after administration in rats. A 25-fold rise in serum bilirubin, a total loss of bile flow, and a decrease in BSP clearance were also observed. Cytochrome P-450 content and EM-N-demethylase activity were significantly decreased to 88% and 66% of control values respectively. A histopathological time course study of CCNU-induced injury showed a progression of acute inflammation, edema, and fibrin deposition in portal areas over 24 h with necrosis and sloughing of bile duct epithelium at 24 and 36 h. Treatment of rats with PB (40 mg/kg/day for 4 days, i.p.) 24 h prior to CCNU administration protected against CCNU-induced hepatotoxicity. Thus, the levels of serum GOT, GPT, and bilirubin were only 2.5 and 4 times higher than in untreated or PB-treated controls. Histopathological examination also showed reduced severity of bile duct lesions in PB-pretreated animals. In rats receiving both PB and CCNU, bile flow was restored and BSP clearance was increased compared to the CCNU-treated rats. The mixed-function oxidase activity in PB + CCNU-treated rats was not significantly different from that in PB-treated controls. It is concluded that pretreatment of rats with PB can markedly suppress the hepatotoxic manifestations, including histopathological changes, the rise in serum bilirubin, and the cholestasis observed in CCNU-treated rats.

Alanine Transaminase↗

PubMed1997

Morphological characterization of the evolving rat spinal cord injury after photochemically induced ischemia.

We have characterized the evolving morphological changes in the adult rat spinal cord following photochemically induced spinal cord ischemia. In cresyl violet-stained sections, disintegration of the tissue at the epicenter was evident at 6 h. This was preceded at 1 h post ischemia by an albumin immunoreactivity. The albumin immunoreactivity was increased at 6 and even more so at 24 h post ischemia. At 72 h post ischemia the albumin immunoreactivity was decreased. The size of the lesion was established by 3 days after the onset of ischemia. During the 1st week post ischemia, neurofilament (NF) immunohistochemistry showed swollen axons adjacent to the injured tissue. From 2 weeks post ischemia an increasing number of regrowing NF-immunoreactive axons could be seen in the center of the necrotic cavity. At 3 weeks after ischemia, a developing gliosis was observed around and rostral to the lesion cavity, as evidenced by increased glial fibrillary acidic protein (GFAP) immunoreactivity. The gliosis became more pronounced until 6 weeks post ischemia, at which time enlarged GFAP-immunoreactive cells could be seen in the remaining viable tissue bordering the necrotic areas. In this study we show that several traits in the development of a spinal cord lesion after photochemically induced ischemia are similar to those described previously after traumatic spinal cord lesions.

Animals↗

PubMed1991

CD3- leukocytes present in the human uterus during early placentation: phenotypic and morphologic characterization of the CD56++ population.

In this study, the CD3- LGL/NK cells present in the pregnant human uterus have been characterized. Phenotypic and morphologic analyses of decidual LGL revealed many similarities to the minor CD56bright+, CD16- subset in peripheral blood, but there were some important differences. The relative surface density of CD56+ is greatly increased on decidual LGL to 22x that found on the majority of CD56+ peripheral blood NK cells. The CD56bright+ cells in decidua show LGL morphology, whereas in peripheral blood, they are mainly agranular. Proliferation of CD56+ cells occurs predominantly during the nonpregnant secretory (luteal) phase, indicating these CD56+ uterine LGL do not migrate as terminally differentiated cells. The appearance of CD56+ cells was examined at the ultrastructural level using immunoelectron microscopy. Cells with phenotypic characteristics of decidual LGL occur in a higher percentage (1.11%) in the peripheral blood of women of reproductive age than in men (0.66%). On the basis of these results, it is proposed that the CD56bright+ uterine leukocytes represent a distinctive, hormonally regulated subset possibly adapted to control human placentation.

Adolescent↗

PubMed2003

Morphological characterization of the Alpha A- and Alpha B-crystallin double knockout mouse lens.

BACKGROUND: One approach to resolving some of the in vivo functions of alpha-crystallin is to generate animal models where one or both of the alpha-crystallin gene products have been eliminated. In the single alpha-crystallin knockout mice, the remaining alpha-crystallin may fully or partially compensate for some of the functions of the missing protein, especially in the lens, where both alpha A and alpha B are normally expressed at high levels. The purpose of this study was to characterize gross lenticular morphology in normal mice and mice with the targeted disruption of alpha A- and alpha B-crystallin genes (alpha A/BKO). METHODS: Lenses from 129SvEvTac mice and alpha A/BKO mice were examined by standard scanning electron microscopy and confocal microscopy methodologies. RESULTS: Equatorial and axial (sagittal) dimensions of lenses for alpha A/BKO mice were significantly smaller than age-matched wild type lenses. No posterior sutures or fiber cells extending to the posterior capsule of the lens were found in alpha A/BKO lenses. Ectopical nucleic acid staining was observed in the posterior subcapsular region of 5 wk and anterior subcapsular cortex of 54 wk alpha A/BKO lenses. Gross morphological differences were also observed in the equatorial/bow, posterior and anterior regions of lenses from alpha A/BKO mice as compared to wild mice. CONCLUSION: These results indicated that both alpha A- and alpha B-crystallin are necessary for proper fiber cell formation, and that the absence of alpha-crystallin can lead to cataract formation.

Animals↗

PubMed2000

Preparation, morphological characterization, and activity of thin films of horseradish peroxidase.

Active uniform films of horseradish peroxidase (HRP) have been prepared by covalent binding on Si/SiO(2) or glass supports previously activated by silanization and succinylation. Labeling by fluorescent or by Electron Spin Resonance (ESR) probes was used to quantify the surface density of active groups and of horseradish peroxidase. Atomic Force Microscopy (AFM) imaging was used to characterize the surface morphology. We observed that a non-uniform protein adsorption due to physical interactions was present when the supports were not activated for covalent binding and was, in large part, removed by washing. The enzyme deposited by covalent binding formed homogeneous layers with a height in the range 60-90 A. By using a fluorescent label, we calculated a protein density of 3.6 x 10(12) molecules cm(-2) on Si/SiO(2), corresponding to an estimated area per molecule of 2800 A(2) which is in agreement with the value expected on the basis of the crystallographic data considering the formation of a monomolecular layer. The protein density of the layer immobilized on glass was similar (1.9 x10(12) molecules cm(-2)). The enzyme immobilized on both supports showed a k(cat)/K(M) being of the order of 3-5x10(5) M(-1)s(-1) that is 1/20th of free HRP. The half-life time of the activity of the enzyme immobilized by covalent binding was longer than 40 days at 6 degrees C.

Bisphenol A-Glycidyl Methacrylate↗

PubMed1981

Morphological characterization of the plasma membrane of a pituitary tumor cell line (GH3).

Freeze-fracturing and deep-etching have been used to characterize the internal morphology and surface charge of the plasma membrane of GH3-cells from cell culture in fixed and unfixed material. Glutaraldehyde does not effect intramembrane particle pattern but induces structural modifications on the cell surface in a way that additional attachment sites for cationized ferritin are exposed at specific areas of the membrane. Negative surface charges are not directly linked to the intramembrane particles, but to other (surface-) proteins, independently enough to be dislocated by external ligands; this process is restricted to the membrane surface. Thermotropic phase changes induce separation of lipidic regions from proteinaceous regions. Peripheral and integral protein are thus aggregated simultaneously, resulting in clustered membrane particles and aggregated surface charges.

Animals↗

PubMed1994

Morphological characterization of the interface between resin and sclerotic dentine.

Since dentine exposed to the oral environment undergoes important compositional and morphological transformations, bonding to it differs significantly from bonding to unaffected normal dentine. In this investigation, the interface between resin and sclerotic dentine, the dentine type clinically exhibited by cervical abrasive or erosive lesions, was morphologically characterized by scanning electron microscopy after an argon-ion-beam etching procedure. The microstructure of the resin-sclerotic dentine interface was compared with that produced to normal unaffected dentine in an attempt to find reasons for the reported less reliable bonding of adhesive resins to sclerotic dentine. A resin-dentine interdiffusion zone or hybrid layer with only a limited width was formed at the hypermineralized intertubular dentine. No or only short resin tags were developed in most dentinal tubules, since their orifices were obliterated due to increased peritubular dentine apposition, intratubular deposition of irregular minerals and formation of so-called sclerotic casts. Consequently, it is reasonable to predict that dentine adhesives with an adhesion strategy, which mainly involves micromechanical interlocking by the formations of a resin-dentine interdiffusion zone combined with resin-tag development into the dentinal tubules, will be less effective when applied to sclerotic dentine than to unaffected normal dentine. An adapted adhesive treatment may be necessary to make sclerotic dentine more receptive to bonding. Further research should be directed to develop adhesive systems that bond equally well to various kinds of dentine.

Acid Etching, Dental↗

PubMed2026

Morphological characterization, genetic diversity and population structure of the rice blast pathogen Magnaporthe oryzae in Northeast India.

The blast pathogen, Magnaporthe oryzae, is one of the most destructive fungal pathogens of rice worldwide, yet its morphological features, genetic diversity and population structure in Northeast India remain poorly understood. In this study, twenty‒two M. oryzae isolates collected from eight states of Northeast India were characterized using morphological, molecular, and population genetic analyses. Morphological characterization revealed whitish to greyish‒white mycelia with sparse sporulation and colony diameters ranged from 36 to 90 mm, classifying the isolates into 14 fast and 8 slow‒growing groups. Whole genome sequencing was performed to enable both ITS‒based identification and SSR locus mining from the assembled genomes. Molecular identification using ITS rDNA sequences confirmed all isolates as M. oryzae, with 95.5-100% similarity. Phylogenetic analysis grouped the isolates into two major clades and identified seven ITS sequence types (GenBank Accessions: PX273287-PX273293). Genetic diversity assessed using 30 SSR markers revealed substantial polymorphism, with 1-7 alleles per locus and polymorphism information content (PIC) values ranging from 0.00 to 0.81. Heatmap clustering, dendrogram analysis, and distance metrics consistently identified two major genetic groups, with some isolates forming nearly identical clusters and others showing moderate divergence. Principal Component Analysis (PCA) and Principal Coordinates Analysis (PCoA) accounted for 87.8% of the total variance (PC1 and PC2 accounted for 54.4% and 33.4% respectively of the total variance) and revealed distinct outliers. Analysis of Molecular Variance (AMOVA) attributed 80% of the total genetic variation to differences among populations while only 20% was attributed to within population differences highlighting significant inter‒population divergence and clonal population structure. The study revealed substantial morphological and genetic diversity among M. oryzae populations in Northeast India, underscoring the need for region‒specific disease management strategies.

India↗

PubMed2001

Molecular and morphological characterization of Tuber magnatum mycorrhizas in a long-term survey.

Tuber magnatum Pico is an ectomycorrhizal fungus whose mycorrhizas can be barely distinguished morphologically from those of other related white truffles. Here we describe the use of specific primers based on the T. magnatum ITS sequence for screening mycorrhizas from a large number of growth chambers, greenhouse and nursery samples taken in a long-term survey. This molecular identification technique enabled a new morphological characterization to be set up for T. magnatum mycorrhizas.

Ascomycota↗

PubMed2006

Microscopic image analysis techniques for the morphological characterization of pharmaceutical particles: Influence of process variables.

This study investigated the effects of various process variables on some of the shape factors most widely used in the morphological characterization of pharmaceutical particles (including circularity, aspect ratio, er, and the recently proposed Vr and Vp). After optimization of the illumination system and greyscale thresholds for discrimination of particle background, we evaluated the effects of process variables within the image capture and analysis system, including the image capture device (video or digital camera), image color information (24-bits-per-pixel RGB or 8-bits-per-pixel black and white), file type (JPG or TIFF), and JPG file compression ratio. A key aspect was evaluation of the effect of scaling factor (microm/pixel), dependent on real pixel size and optical magnification, on shape factor estimates. The results obtained indicate that accurate estimation of shape factors requires use of a scaling factor below a certain maximum; however, use of very low scaling factors will mean that the field of view is very small, so that it will contain very few particles, implying a time-consuming increase in the number of images that must be analyzed. Finally, we use statistical procedures to estimate the minimum number of particles that must be analyzed in order to provide accurate estimates of shape factors.

Chemistry, Pharmaceutical↗

PubMed2003

Morphological characterization of different human cervical mucus types using light and scanning electron microscopy.

BACKGROUND: This study was conducted on human cervical mucus using light microscopy (LM) and scanning electron microscopy (SEM). The objective was the morphological characterization of the different mucus types, with samples taken from the lumen of the cervix and from the different secretory zones of the cervical mucosa. METHODS: A total of 230 samples from 195 women were spread out on slides and air dried. The phenomenon of 'ferning' was observed and assessed in these samples using both LM and SEM. Further samples from the lumen of the cervix and the different secretory crypts were spread out on cover slips and fixed with glutaraldehyde (2.5%) to be studied by SEM. RESULTS: The results show the presence of four different morphological mucus types, namely L, S, P and G, in both types of sample using dried and fixed techniques. CONCLUSIONS: Mucus from the lumen of the cervix appears to be a morphologically heterogeneous entity. It contains different types of secretions, the proportions of which vary throughout the menstrual cycle. The different mucosal types show different types of crystallization, different patterns of ultrastructure (probably related to the arrangement of the glycoprotein network) and are produced in different secretory zones of the crypts in the cervix.

Adult↗

PubMed1993

Morphological characterization of a new human epithelioid sarcoma cell line, ES020488, in vitro and in vivo.

A new human epithelioid sarcoma cell line (ES020488) was established from a cutaneous metastasis in 26-year-old man, and was morphologically characterized in vitro and in vivo by comparison with the original tumor. The ES020488 cells showed a male karyotype ranging from 39 to 83 chromosomes, with various abnormalities but no specific pattern. The cells were round, polygonal or spindle-shaped with abundant cytoplasm and round nuclei containing prominent nucleoli; they proliferated in a sheet-like pattern. Tumors transplanted into nude mice revealed essentially the same features as the original tumor. Both in vitro and in vivo, the cells immunohistochemically expressed vimentin, cytokeratin, and EMA, but not desmin and S-100 protein. Ultrastructural study revealed irregular or round nuclei containing abundant euchromatin and prominent nucleoli, many intermediate filaments running irregularly or around the nucleus, and a number of filopodia-like processes. ES020488 cells were thus proven to retain and exhibit the unique morphological characteristics of an epithelioid sarcoma both in vitro and in vivo. These cells are possibly derived from synovioblastic mesenchyme.

Adult↗

PubMed1980

The establishment and morphologic characterization of finite cell lines from normal human endometrium.

Twenty-nine samples of normal human endometrium have been initiated in tissue culture. Twenty cultures (69%) demonstrated sufficient growth in vitro to allow establishment of finite cell lines. Morphologic characterization by means of conventional light microscopy as well as scanning and transmission electron microscopy was performed. Differences between stromal and epithelial cell lines indicated several similarities with in vivo observations. Ultrastructural studies of stromal cell lines revealed cells virtually devoid of microvilli and exhibiting poorly specialized cell junctions. Epithelial cell lines were characterized by numerous microvilli and highly specialized "junctional complexes" typical of glandular epithelium. Cytogenetic analysis utilizing a variety of banding techniques revealed no karyotypic alterations through several subpassages. Our observations suggest that simple explant tissue culture of human endometrium can be manipulated in order to achieve separation of stromal from epithelial elements, allowing critical examination of each.

Cell Line↗

PubMed1995

A morphological characterization of Borrelia anserina.

The morphology and ultrastructure of two strains of Borrelia anserina were investigated by electron microscopy of negatively stained and ultrathin sectioned cells. One was a cultivable strain originally isolated in the USA and the other was originally isolated in Nigeria and maintained in chickens. The cells were regularly helical, 9-21 microns long and 0.22-0.26 microns wide with a helix wavelength of about 1.7 microns. The cells were surrounded by a surface layer and appeared to divide by binary fission. The structure of the cells from each of the two strains was identical except that those of the USA strain possessed seven flagella inserted at each end and those from the Nigerian strain had eight.

Animals↗

PubMed1991

Morphological characterization of a newly established human osteosarcoma cell line, HS-Os-1, revealing its distinct osteoblastic nature.

A newly established human osteosarcoma cell line, HS-Os-1, from an osteoblastic tumor arising in the left humerus of an 11-year-old girl was morphologically characterized in vitro and in vivo. HS-Os-1 cells in a monolayer have been maintained for more than 2 years since the initial cultivation, and were round or polygonal in shape with marked pleomorphism. Their cytoplasm was strongly positive for specific markers of osteoblasts, such as alkaline phosphatase and osteocalcin. Tumors induced in nude mice by HS-Os-1 cell inoculation at passage 12 or 23 revealed typical histological features of osteoblastic osteosarcoma, similar to those observed in the original tumor, producing prominent osteoid matrix with calcification. Ultrastructurally, HS-Os-1 cells in vitro and tumor cells in vivo showed similar well-developed, markedly dilated rough endoplasmic reticulum, polysomes and microfilaments in their cytoplasm. Additionally, many collagen fibers associated with deposition of electron-dense material were detected in the stroma featuring osteoid matrix. Thus, the HS-Os-1 cell line was shown to exhibit its osteoblastic nature in vitro and in vivo, and therefore might become an extremely useful tool for various pathomorphological investigations on human osteosarcomas.

Animals↗

PubMed1998

[Clinical and morphological characterizations of first detected cases of caseous pneumonia and its outcomes under conditions of current antibacterial therapy].

The paper provides a clinical and X-ray picture of first detected caseous pneumonia. It shows the potentialities of currently available antibiotic therapy used in patients with this diagnosis. At the same time closure of decay cavities and eradication of bacteria can be achieved only in 29% of cases. The major outcome of caseous pneumonia is fibrocavernous tuberculosis. Thus, surgical methods must play an important role in curing such patients. A detailed morphological characterization of surgical materials has demonstrated that active chemotherapy may result in 3 types of caseous pneumonia outcomes: acute progression, chronicity tended to progression, and the development of fibrocavernous tuberculosis. The morphological studies have provided evidence for the validity of the clinical and X-ray dynamics of the disease and for the correctness of choice of surgical policy.

Antitubercular Agents↗

PubMed1978

Biochemical and morphological characterization of subcellular fractions isolated from rabbit colon muscle.

From a homogenate of rabbit colon muscle subcellular fractions were isolated by differential centrifugation. The crude microsomal fraction could be separated into subfractions, a fraction of vesicular microsomes at 35% sucrose, a fraction containing sarcolemma, mitochondrial fragments and microsomal vesicles at 35--45% sucrose and a small protein fraction at 45--55% sucrose. Their biochemical properties and their morphological characterization were investigated. The cholesterol and the phospholipid content was equally distributed between the microsomal fractions 35% and 35--45% while the RNA was localized to the mitochondria and the microsomal fraction 35%. The enzyme cytochrome c oxidase was found to be concentrated in the mitochondria while a high contamination was found in the microsomal fractions 35--45%. The NADH-oxidase activity was highest in the 35% fraction and the 5'-nucleotidase activity in the 40,000 X g supernatant. The microsomal subfractions contained the enzymes ATPase, adenylate cyclase and phosphodiesterase. In the 35% fraction Ca stimulated the hydrolysis of ATP. The binding of [3H]-ouabain and the incorporation of [3H]-leucine was most pronounced in the 35% fraction. In a K+-free Krebs Ringer medium the binding of the glucoside was stimulated in all the fractions. From these results we concluded that the fraction 35% sucrose may be mainly derived from the endoplasmic reticulum and the plasma membrane while the 35--45% originates from the plasma membrane, mitochondria and to a lesser extent the endoplasmic reticulum.

Adenosine Triphosphatases↗

PubMed2006

Chemical, physical, structural and morphological characterization of the electric arc furnace dust.

Electric arc furnace dust (EAFD) is a hazardous industrial waste generated in the collection of particulate material during steelmaking process via electric arc furnace. Important elements to the industry such as, Fe and Zn are the main ones in EAFD. Due to their presence, it becomes very important to know how these elements are combined before studying new technologies for its processing. The aim of this work was to carry out a chemical, physical, structural and morphological characterization of the EAFD. The investigation was carried out by using granulometry analysis, chemical analysis, scanning electron microscopy (SEM), energy dispersive spectroscopy via SEM (EDS), X-ray mapping analysis via SEM, X-ray diffraction (XRD) and Mössbauer spectroscopy. By XRD the following phases were detected: ZnFe(2)O(4), Fe(3)O(4), MgFe(2)O(4), FeCr(2)O (4), Ca(0.15)Fe(2.85)O(4), MgO, Mn(3)O(4), SiO(2) and ZnO. On the other hand, the phases detected by Mössbauer spectroscopy were: ZnFe(2)O(4), Fe(3)O(4), Ca(0.15)Fe(2.85)O(4) and FeCr(2)O(4). Magnesium ferrite (MgFe(2)O(4)), observed in the XRD pattern as overlapped peaks, was not identified in the Mössbauer spectroscopy analysis.

Brazil↗