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Results for “Morphological Characterization”

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PubMed2000

Giant cell arteritis and Takayasu aortitis: morphologic, pathogenetic and etiologic factors.

Overlapping features among aortitides are relatively common although the underlining etiologies may differ. Thus, the clinical classification of aortitides is rather difficult and often misleading. Furthermore, morphologic characterizations of these vascular disorders are frequently overlapping and therefore additional clinical and radiologic information is usually required. The greater challenge is aortitides is whether the initiation is due to an exogenous stimulus or due to an autoantigen.

Aorta↗

PubMed1989

Normal human immune peritoneal cells: phenotypic characteristics.

Normal human peritoneal cells (PC) collected from patients with calculous cholecystitis without clinically detectable inflammatory changes were characterized morphologically, histochemically and phenotypically by means of monoclonal antibodies. The PC consisted of 45% of monocytes/macrophages (M718 + cells). Thirty-five per cent of PC were esterase-positive and 23% acid phosphatase positive. Forty-five per cent of PC adhered to glass surface. In the lymphocyte population, 2% of CD22 B lymphocytes (M738 +) and 42% CD2 T lymphocytes (M720+) were found. CD4/CD8 ratio was 0.4. There were 8% of Leu7 + cells. The PC did not reveal interleukin 2 (OKT26a +) and transferrin receptors (OKT9 +) on their surface. No blast cells were detected in the PC suspension. Approximately 49% of the PC expressed Ia antigens (OKIa1 +). Two per cent of S100 positive dendritic cells (Z311 +) were found. Peritoneal fluid contained 9% of granulocytes, mostly neutrophils. Two per cent of PC were free mesothelial cells (M717 +). We conclude that human peritoneal cavity contains a cell population significantly differing from that which is present in peripheral blood, which strongly suggests a non-random cell accumulation in the peritoneum. Lack of any activated cells indicates that under normal conditions the peritoneum lavage fluid contains a steady-state population. We conclude that the normal peritoneal fluid cells represent a heterogeneous population capable of reacting to various antigens entering the cavity from the gut.

Adult↗

PubMed1996

Blood cell markers.

Cytochemistry and immunocytochemistry are important adjunctive technologies to the morphologic characterization of blood cells and hematopoietic neoplasms. Although cytochemistry is briefly discussed, the emphasis of this article is on the clinical application of flow cytometry and leukocyte monoclonal antibodies in veterinary medicine. Classification and significance of immunophenotyping in canine and feline lymphomas and immunodeficiencies such as feline immunodeficiency virus and feline leukemia virus are discussed.

Animals↗

PubMed2002

Arachidonic acid cytotoxicity in leukocytes: implications of oxidative stress and eicosanoid synthesis.

Arachidonic acid (AA)-induced cytotoxicity was evaluated in leukocytes: the human leukemia cell lines HL-60, Jurkat and Raji and in rat lymphocytes. Such cytotoxicity was dose- and time-dependent. At concentrations below 5 microM, AA was not toxic; at 10-400 microM, AA induced apoptosis and at concentrations beyond 400 microM, necrosis. The minimum exposure time to trigger cell death was of around 1 h, but the effect was increased by longer exposure times until 6-24 h. Apoptosis was morphologically characterized by a decrease in cell and nuclear volume, chromatin condensation and DNA fragmentation and the presence of lipid bodies, without changes in organelle integrity. Biochemically, AA-induced apoptosis was associated with internucleosomal fragmentation and caspase activation, evaluated by PARP cleavage and the use of a caspase inhibitor. Necrosis was characterized by increased cell volume, presence of loose chromatin, appearance of vacuoles, loss of membrane integrity and of the definition of organelles. The apoptotic effect of AA was studied as to oxidative-reductive imbalance and the participation of eicosanoids. Apoptotic AA treatment was accompanied by an increase in the quantity of thiobarbituric acid reactive substances (TBARS), low-level chemiluminescence and in the glutathione disulfide/reduced glutathione ratio, indicating oxidative stress. The addition of tocopherol, ascorbate, prostaglandin E2 and lipoxygenase inhibitors delayed cell death, whereas the inhibition of cyclooxygenase promoted AA-induced cell death. Cell treatment with AA was accompanied by increased cellular production of LTB4. AA, therefore, is cytotoxic at physiological and supraphysiological concentrations, causing apoptosis and necrosis. Cell treatment with apoptotic concentrations of AA involves oxidative stress and changes in eicosanoid biosynthesis.

Animals↗

PubMed1983

[Hemato-encephalic barriers. Morphologic data].

Within the cranio-spinal cavity we can consider three compartments: blood, cerebro-spinal fluid and nervous parenchyma and thus, three barriers (Blood-Cerebro-Spinal Fluid, Blood-Brain, Cerebro-Spinal Fluid-Brain). The morphological studies of these barriers were performed with exogenous tracers such as horseradish peroxidase, cytochrome C and ferritin or endogenous tracers such as autologous antiperoxidase immunoglobulins. 1. The blood-brain barrier is exogenous and endogenous tracers proof. It is found on the level of the brain capillary endothelium with tight junctions and rare plasmalemmal vesicles. 2. The blood-cerebro-spinal fluid barrier is found on the level of choroid plexus and of leptomeningeal vessel. In the former, the tracer is stopped by the tight junctions (zonula occludens type) of the choroid plexus epithelium. Besides, there is no morphological evidence of transepithelial passage from blood to cerebro-spinal fluid. In the later, the barrier is, almost always, found on the level of the vascular endothelium. 3. The parenchymatous-cerebro-spinal fluid interface cannot be called a barrier because the diffusion of the tracers is not restricted either by the astrocytic marginal layer or by the ependyma. The circumventricular organs other than choroid plexus are morphologically characterized by the free diffusion of tracers in their perivascular connective space. Subcommissural organs capillaries alone behave like those of the brain. The spinal cord capillaries, in opposition to those of the brain, are characterized by a perivascular connective space, for 40 p. 100 of them. The significance of this fact is still unknown.

Anti-Bacterial Agents↗

PubMed1999

Global ischemia and behavioural deficits.

Global cerebral ischemia in rodents is an established model in experimental research on cerebral ischemia which is characterized morphologically by a selective neuronal damage in the hippocampus, striatum and cortex. Using this model many studies have been performed to examine the pathophysiology of ischemic neuronal damage. Based upon these results it has been analysed whether substances which interact with the pathophysiological processes reduce the ischemic neuronal damage. Besides the morphological changes global ischemia leads to functional changes which can be assessed by behavioural studies. The Morris water maze examines the animals' abilities to learn, remember and go to a place in space only defined by its position relative to distal extramaze cues. In this test ischemic animals display a deficit in spatial learning as revealed by an increase in latency and in swim distance in the escape trials and a deficit in spatial memory as shown by reduced quadrant time and crossings over the former platform position during the probe trial. In several studies it could be demonstrated that neuroprotective strategies which reduce ischemic neuronal damage also attenuate or even completely prevent the ischemia-induced behavioural deficits in the water maze. Transplantation of fetal tissue which can also be used to achieve morphological recovery following global ischemia results in an amelioration of the ischemia-induced deficit. Thus, the water maze can clearly show that transplanted tissue can be functionally relevant. Data from the water maze seem to be a valuable completion to morphology which is especially important with respect to the relevance of experimental studies for clinical trials.

Animals↗

PubMed1987

Early infantile form of neuronal ceroid lipofuscinosis. Four Dutch cases and review of the literature.

In this paper four Dutch cases of early infantile neuronal ceroid lipofuscinosis (NCL) are described, all being boys. NCL is a group of diseases morphologically characterized by accumulation of autofluorescent ceroid lipofuscin-like pigment. Psychomotor deterioration, impairment of vision, and epileptic manifestations are the major clinical features. Onset in early infantile age is rare. We reviewed 71 cases reported in the literature, and compared the symptoms and signs with the findings in our patients. Psychomotor deterioration, visual impairment and myoclonic jerks are often observed early in the disease. Eventually, every patient shows psychomotor deterioration. The outcome is always lethal, usually within a few years. Special attention is paid to diagnostic procedures.

Child↗

PubMed2000

Highly crystalline faujasitic zeolites from flyash.

The process for the synthesis of flyash-based zeolites (FAZs) are presented, which basically includes alkaline treatment of flyash by a fusion method, followed by hydrothermal crystallization. Zeolite-Y has been identified, and conditions have been optimized for their synthesis by the fusion method. Optimal conditions for synthesis of Zeolite-Y are a NaOH/flyash ratio of 1.2:1, fusion temperature between 500 degrees C and 600 degrees C, crystallization time of 8-10 h and crystallization temperature between 100 degrees C and 110 degrees C. The cation exchange capacity (CEC) of FAZ-Y ranges between 400 and 450 meq/100 g. The surface area of FAZs (500-600 m(2)/g) compare well with the commercial zeolites procured from Mobil Oil. Morphological characterization of FAZ using scanning electron microscopy (SEM) reveals cubic structure, and XRD data reveal unit cells to be cubic system.

Crystallization↗

PubMed2003

Survey of ixodid tick species on domestic cats in Japan.

Various species of ixodid ticks, attached to domestic cats in Japan, were identified in spring (April to June) and autumn (September to November). In the spring, a total of 282 ticks, including 61 larvae, 70 nymphs, 127 females and 24 males were collected from 126 cats. Of these, 264 were identified up to the species level. In the spring, Haemaphysalis longicornis was the most frequently (39.7%, 50/126) found tick species on feline hosts, followed by Ixodes ovatus (35.0%, 44/126), Ixodes nipponensis (15.9%, 20/126) and Haemaphysalis flava (9.5%, 12/126). Small numbers of Haemaphysalis megaspinosa, Haemaphysalis japonica, Ixodes persulcatus, Ixodes granulatus and Amblyomma testudinarium were also recovered. H. longicornis was the most frequently found tick species on cats around riversides or river basins, while I. ovatus and I. nipponensis were more frequently found on cats kept near woodland or related areas. I. nipponensis was more frequently found on castrated males. No major statistical differences in the frequency of tick attachment among sex, age or hair length for the three major tick species were found. Of 205 ticks including 173 (84.4%) larvae, 27 (13.2%) nymphs, 4 (2.0%) females and 1 (0.5%) male recovered from 62 cats in autumn, only 32 (15.6%) were identified. Most of the larvae were fully- or partly-engorged Haemaphysalis spp., and it was difficult to identify them further by morphological characterization.

Age Factors↗

PubMed1990

Some histological remarks on the fibrolamellar carcinoma of the liver.

Investigations on five fibrolamellar carcinomas of the liver suggest that this tumor originates from purely epithelial proliferations, while the ensuing fibrous growth leading to lamellar formations is but a secondary event. Nevertheless, progressing fibrosis has a considerable influence on cell shape as the surrounded cell complexes are quasi immured, and their supply and transport procedures impaired. Its influence further evokes a compensatory increase of mitochondria so that, in advanced cases, these cells may be mistaken for genuine oncocytes, although the appraisal of an oncocytic tumor is not confirmed. At this point only, increased amount of fibrinogen-containing (endoplasmic) vacuoles and PAS positive globuli are interpreted as phenomena of cellular retention, and so is the accumulation of unexcretable copper. Ultimately, this fibrous incarceration will cause cell death, destruction and depletion resulting in abundant scarring especially in the center of the focus, without, however, signalling any close relationship with focal nodular hyperplasia. Excess fiber formation exerts a proliferation-inhibiting effect resulting in slower growth and consequently, in the more favorable prognosis of this tumor of distinctive and well-characterized morphology.

Adenoma↗

PubMed1987

The role of immunohistochemistry, electron microscopy, and ultrastructural cytochemistry in the diagnosis of mixed carcinoma-neuroendocrine neoplasms.

We studied four mixed carcinoma-neuroendocrine neoplasms from gastrointestinal tract and pancreas by routine light microscopy (LM), immunohistochemistry (IH), electron microscopy (EM), and ultrastructural cytochemistry (UC). By LM, the individual tumors showed fairly pure neuroendocrine (carcinoid) or epithelial (papillary) patterns, mixed neuroendocrine-carcinoma features and poorly-differentiated tumor in sheets and nests which did not lend itself to morphologic characterization. IH demonstrated mixed expression, within different areas of the same neoplasm, of epithelial antigens (keratins and carcinoembryonic antigen [CEA]) and neuroendocrine markers (neuron-specific enolase [NSE], bombesin and neurohormonal peptides). By EM, each tumor showed ultrastructural features of epithelial and neuroendocrine differentiation which varied substantially in terms of number of cells involved and their distribution; two of the neoplasms showed biphasic differentiation within single cells. The nature of the neurosecretory granules was verified with the uranaffin reaction (UR). This study illustrates the value of combining LM, IH, EM and UC for the identification of mixed carcinoma-neuroendocrine lesions.

Aged↗

PubMed1996

Detection of ras oncogene point mutations and simultaneous proliferative fraction estimation in gallbladder cancer.

Gallbladder cancer is notorious for its poor clinical evolution; so, a study of parameters with any prognostic potential is of particular interest. In this study, we investigated 23 adenocarcinomas regarding both the presence of point mutations in the ras gene family and the quantitative expression of Proliferating Cell Nuclear Antigen (PCNA). We respectively used molecular biology techniques and immunohistochemistry. Our results were related to several clinicopathologic determinators as well as to patients' survival. Mutations in codon 12 of the K-ras gene were detected in four gallbladder neoplasms (17%). This specific type of mutation is likely to be partially involved in this organ's tumourigenesis, particularly since no H-ras codon 12 or K-ras codon 13 (aspartic acid) mutations were detected in any of our specimens. PCNA immunoreactivity was generally limited in all tumours studied except for those morphologically characterized as being particularly aggressive. Notably, the four tumours in which K-ras mutation was detected, demonstrated relatively high PCNA positive immunoexpression in their malignant cells. This finding reinforces a possible correlation between the presence of ras mutations and increased cell growth. Staging was the only factor which was statistically associated with survival (p < 0.01). Therefore, the poor evolution of this cancer is probably due to late diagnosis and not related to a model of increased biologic aggressiveness.

Adult↗

PubMed2000

Study on glycolic acid delivery by liposomes and microspheres.

Glycolic acid is used in many cosmetic products as exfoliant and moisturizer. Unfortunately, the greater glycolic acid cosmetic benefits the greater is the potential for skin irritation as far as burning. The aim of this work was to investigate the feasibility of topical controlled delivery systems loading glycolic acid in order to optimize the acid cosmetic properties lowering its side effects. For this purpose different types of microparticulate systems have been evaluated: liposomes, liposomes modified by chitosan addition and chitosan microspheres. Liposomes, composed of phosphatidylcholine and cholesterol (1:1 molar ratio) and with different glycolic acid/lipid molar ratio, were prepared by reverse phase evaporation method. Two types of interaction between liposomes and chitosan were investigated: chitosan addition into lipidic bilayer during liposome preparation and coating of already formed liposomes with chitosan. Glycolic acid loaded chitosan microspheres were prepared by the dry-in-oil emulsion method. The microparticulate systems were morphologically characterized by electron microscopy and particle size analysis. In vitro dissolution tests were performed to evaluate the feasibility of microparticulate systems in modulating glycolic acid release. The results obtained show that liposomes are always suitable to modulate glycolic acid release and that the best condition to achieve this control is obtained by the liposomal systems in which glycolic acid/lipid molar ratio is 5:1. Further significant release control is obtained by addition of chitosan into the liposomes, while chitosan microspheres are not able to control glycolic acid release even after crosslinking.

Administration, Topical↗

PubMed1996

Characterization and development of an inner ear type I fibrocyte cell culture.

A method has been developed that allows successful maintenance of secondary cell cultures derived from explants of the cochlear lateral wall of young adult gerbils. The secondary cultures were characterized morphologically with light and transmission electron microscopy and immunocytochemically with protein markers specific to various lateral wall cell types. Structural studies revealed fusiform-shaped cells with a paucity of cytoplasm surrounding the nucleus and slender processes. The cells showed little evidence of intercellular contact even when confluent. The cultures were immunopositive for vimentin, carbonic anhydrase isozyme II, creatine kinase isozyme BB and smooth endoplasmic reticulum Ca-ATPase, but lacked reactivity for cytokeratins and Na,K-ATPase. The results indicate that the cultures are comprised of type I fibrocytes from the spiral ligament. These findings are the first to demonstrate that inner ear spiral ligament cells can be isolated and maintained in secondary culture while retaining many of their in vivo characteristics. Based upon their location and content of ion transport enzymes, type I fibrocytes are thought to be involved in the recycling of potassium from perilymph into the stria vascularis. The establishment of this cell line provides a means to analyze the role of spiral ligament fibrocytes in maintenance of inner ear homeostasis.

Animals↗

PubMed2002

COX-2 selective NSAID decreases bone ingrowth in vivo.

Whether non-steroidal anti-inflammatory drug (NSAID)-induced suppression of bone ingrowth is due to cyclooxygenase-1 (COX-1) inhibition, cyclooxygenase-2 (COX-2) inhibition, or through a yet unidentified pathway is unknown. In this study, the effects of a non-specific COX-1 and COX-2 inhibitor, versus a specific COX-2 inhibitor on bone ingrowth and tissue differentiation are examined in vivo. Harvest chambers were implanted unilaterally in the tibiae of eight mature, New Zealand white rabbits. After a 6-week period for osseointegration of the chamber, the following oral treatments were given for 4 weeks each, followed by a harvest in each case: drinking water with no NSAID (control 1), Naproxen sodium--a COX-1 and COX-2 non-specific inhibitor at a dose of 110 mg/kg/day in the drinking water, drinking water with no NSAID (control 2), and Rofecoxib-a COX-2 inhibitor at a dose of 12.5 mg/day inserted directly into the rabbit's mouth. Harvested specimens were snap frozen, cut into serial 6 microm sections and stained with hematoxylin and eosin for general morphological characterization, and alkaline phosphatase (osteoblast marker). Sections were also processed for immunoperoxidase staining using monoclonal antibodies to identify cells expressing the vitronectin receptor (osteoclast-like cells). With drinking water alone, the percentage of bone ingrowth averaged 24.8 +/- 2.9% and 29.9 +/- 4.5% respectively. Naproxen sodium in the drinking water and oral Rofecoxib decreased bone ingrowth significantly (15.9 +/- 3.3%. p = 0.031 and 18.5 +/- 2+/-4%, p = 0.035 compared to drinking water respectively). Both Naproxen sodium (p = 0.026) and Rofecoxib (p = 0.02) decreased the number of CD51 positive osteoclast-like cells per section compared with drinking water alone. Rofecoxib decreased the area of osteoblasts per section area (p = 0.014) compared to controls, although the value for Naproxen sodium did not reach statistical significance. The results of the present study suggest that bone formation is suppressed by oral administration of an NSAID which contains a COX-2 inhibitor. COX-2 inhibitors currently taken for arthritis and other conditions may potentially delay fracture healing and bone ingrowth.

Animals↗

PubMed1997

Lack of biocytin transfer at gap junctions in the chicken vestibular nuclei.

In vivo experiments were designed to test for functional gap junctions at 'mixed' synapses that were morphologically characterized between the large-diameter, primary vestibular fibers and second-order vestibular neurons in the chicken, Gallus gallus. In previous intracellular recordings and dye injections into these neurons from brain slice preparations of chick embryos (E15/16) and also newborn hatchlings (HI-2), no evidence was obtained for functional gap junctions. Therefore, biocytin, a low molecular weight tracer that permeates gap junction channels, was extracellularly applied to either the ampullary nerves or to the vestibular ganglion of 3-6 day old hatchlings and adult chickens (9 months). This procedure resulted in the uptake of the dye and heavy staining of both the thick and thin fibers composing the vestibular nerve and in loading of vestibular efferent neurons. However, no dye transfer was observed between the large-diameter, primary vestibular fibers and second-order vestibular neurons. This observation, which was performed using a relatively non-invasive approach on intact animals, suggests that the gap junctions at these mixed synapses are probably not functional under the conditions of these experiments.

Animals↗

PubMedDate not supplied

The development of the blood-brain barrier in alcohol-exposed rats.

Circulating horseradish peroxidase (HRP) was used as a tracer to determine if the blood-brain barrier to protein was altered by dietary prenatal alcohol exposure. Animals were prepared for light microscopic visualization of HRP after HRP infusion on gestational days 16, 18, 20, 22 and postnatal day 4. There was no consistent evidence of HRP leakage through the BBB in the alcohol-exposed animals compared to control animals. Capillary endothelial cells and perivascular astrocytic endfeet were morphologically characterized by electron microscopy in rat optic nerve and cerebellum following dietary prenatal and postnatal ethanol exposure. Photomontages of optic nerve capillaries from G20 and P5 animals and cerebellar capillaries from P15 animals were examined for evidences of effects of alcohol on the development of the capillaries and adjacent astroglial endfeet. There was no consistent evidence of any alcohol-induced effect that could indicate a disruption of the vessel, the endothelial tight junctions, the perivascular glial limiting membranes, or the extent of vascular ensheathment by astrocytic endfeet.

Animals↗

PubMedDate not supplied

[Granzymes A and B in pulmonary sarcoidosis (experimental study)].

Sarcoidosis is a systemic disease of unknown aetiology, morphologically characterized by well-formed epithelioid granulomas, which show little or no central necrosis. These may be present in any organ or tissue. The lung is the most frequently and prominently involved target. The granuloma is often very sharply demarcated from the adjacent tissue and is surrounded by a mantle of lymphocytes, which mediate lysis of target cells by various mechanisms, including exocytosis of lytic proteins, perforins and granzymes. Sarcoidosis laboratorial diagnosis is usually made by SACE and Lisozyme dosages. The granzymes A and B could be two other markers of the disease, since the sarcoidosis granuloma is rich in cytotoxic and NK cells. An ELISA Kit was used to measure Granzyme A and B in serum of a normal control group (NC) (n=30), and in two groups with lung pathology: one without sarcoidosis, disease control (DC) (n=21) and other with sarcoidosis (S) (n=11). Our results showed that SACE activity is significantly augmented in S group comparing with NC and DC, respectively: 82,6+/-32,7/31,9+/-17,8 - p=0,00017 and 82,6+/-32,7/31,9+/-17,8 - p=0,00024. Lisozyme activity is significantly augmented in S and DC groups comparing with NC. Granzyme B showed a significant decrease in DC and S groups comparing with NC. Granzyme A showed a significant decrease between S/NC groups. Our results suggest that the decrease of Granzyme A and B in sarcoidotic patients could be related to an ineffective inflammatory local response related to the formation of sarcoidosis granulomas. More studies are needed, particularly in BAL.

Adolescent↗