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PubMed1987

Immature T lymphocytes after injury characterized by morphology and phenotypic markers.

Changes in the peripheral blood mononuclear cell (PBMC) population in patients following both thermal and nonthermal injury were defined by both morphological characteristics and surface phenotype with the monoclonal antibodies T6, OKT9, OKT10, and OKIa1, using a fluorescence activated flow cytometer with gating to separate small cells of the lymphocyte series from larger forms. Lymphocytes with surface antigens that bind T6, OKT9, and OKT10 are rarely found in the peripheral blood of adult patients, except in those with malignancies of the lymphoid system. In both burn and trauma patients the percentage of lymphocytes in the PBMC population after Ficoll-Hypaque separation was significantly reduced as compared with normal controls due to increases in the number of granulocytes, large granular lymphocytes (LGL), and monocytes, often present in immature forms. T6 cells were found in significantly greater numbers in both burn and nonthermal injury patients than in a control group using both small and wide gate settings on the fluorescence-activated flow cytometer. Significant increases in the number of T9+ cells also were observed in both groups for a prolonged period following injury. Significantly increased numbers of the T10+ and Ia1+ cells were detected in burn patients. The response to injury, therefore, involves the appearance in the peripheral blood of immature cells that may express T6, T9, T10, and Ia1 surface antigens. These cells may be present in quantities otherwise seen only in malignant disease.

Adolescent↗
PubMed1996

Isolation and in vitro propagation of human choroidal fibroblasts. Morphology and characterization of the cultures.

Subretinal ingrowth of choroidal fibroblasts is of importance in several clinical settings such as age-related macular degeneration or after traumas such as laser treatment and infection. In the present investigation we describe a method for isolation and propagation of human choroidal fibroblasts in vitro. Outgrowth from the outseeded choroid was studied by means of phase contrast microscopy, scanning electron microscopy and by immunohistochemical methods. The secondary cultures were found to contain almost only fibroblasts (more than 95% of the cells), some contaminating retinal pigment cells were also found. Choroidal fibroblasts contribute to the fibrovascular subretinal scarring process, and our cell culturing system seems to be a suitable tool for studying factors regulating the behavior of these cells in vitro.

Aged↗
PubMed1992

Characterization of morphologic changes and lymphocyte subset distribution in lymph nodes from cats with naturally acquired feline immunodeficiency virus infection.

Lymph nodes were collected at biopsy or necropsy from 18 cats with naturally acquired symptomatic feline immunodeficiency virus (FIV) infection and from 18 seronegative cats. Thirty-five of the cats were domestic shorthairs and one was a Persian cross. The cats ranged from 7 months to 16 years of age and were mainly obtained from California veterinary practitioners, a California cattery, and a Veterinary Teaching Hospital. Based on clinical signs present at tissue collection, ten FIV-infected cats fell into the acquired immunodeficiency syndrome (AIDS)-related complex (ARC) clinical stage and eight in the terminal (AIDS) stage of FIV disease. All cats were FeLV negative by antigen ELISA. Histologic sections of lymph nodes from each cat were examined blindly and were categorized as hyperplastic, involuting, mixed hyperplastic and involuting, depleted, or normal based upon subjective evaluation of follicles and paracortex. The relative abundance of plasma cells was evaluated in methyl green pyronin (MGP) and hematoxylin and eosin-stained sections. Similar numbers of FIV-seropositive and -seronegative cats fell into each lymph node category. The only difference evident between FIV-infected cats and control cats was in the degree of plasmacytosis present; moderate to marked plasmacytosis was present in 13/18 FIV-infected cats but in only 3/18 control cats.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2002

Characterization of morphological and cytoskeletal changes in trophoblast cells induced by insulin-like growth factor-I.

IGF-I and IGF-II were appeared to play major roles in the adhesive and migratory events that are considered to be crucial in the implantation process. The purpose of this study was to determine the effects of IGF-I on trophoblast adhesion to extracellular matrix. Trophoblast cells obtained from early gestation at artificial abortion were incubated with the indicated doses of IGF-I at the indicated times. Trophoblast cells were treated with IGF-I in the presence or absence of RGD peptide and an antibody against alpha-subunit of IGF-I receptor (alphaIR3). Morphometric and morphological changes were studied using light and electron microscopy. Furthermore, vinculin, actin stress fibers, phosphorylated focal adhesion kinase (FAK), phosphotyrosine, and paxillin were immunolocalized in trophoblast cells after IGF-I treatment in the presence or absence of alphaIR3. Immunoprecipitation and anti-phosphotyrosine immunoblotting were carried out to detect the phosphorylated FAK and phosphorylated paxillin contents of the IGF-I-treated and untreated trophoblast cells. The results showed that IGF-I promoted trophoblast adhesion to fibronectin substrate in a time- and dose-dependent manner, and addition of RGD peptide and alphaIR3 monoclonal antibody abolished the effects of IGF-I in these cells. Morphological studies exhibited an increase in the lamellipodia formation upon IGF-I treatment, and confocal images of immunofluorescent staining revealed localization of phosphorylated FAK, paxillin, and vinculin at focal adhesions as well as redistribution of actin microfilaments and formation of actin stress fibers inside the cell. Western blotting, using antiphosphotyrosine demonstrated proteins with molecular masses of 125 kDa (FAK) and 68 kDa (paxillin) present in the IGF-I-treated cells, which were lacking in the control groups. In conclusion, these findings suggest that IGF-I can stimulate lamellipodia formation and promote adhesion of trophoblast cells to extracellular matrix by activating their adhesion molecules that must be activated within the implantation window.

Cell Adhesion↗
PubMed1988

Storage of human red blood cells and platelets. Some aspects concerning the factors leading to storage lesion characterized as morphological changes and vesiculation. Minireview based on a doctoral thesis.

1. Storage renders erythrocytes more responsive to thermally induced morphological changes, especially the shedding of microvesicles. 4-8 week old cells can be morphologically "rejuvenated" by heating. 2. If pH increases during storage of platelets an extensive loss of small particles occurs. The platelet disintegration is associated with a loss in the metabolic activity, discharge of LDH, increased susceptibility to phospholipid hydrolysis by phospholipase C and is found to be initiated during the actual preparation of platelet concentrates. 3. Activation of platelets during preparation can be decreased by shortening the first centrifugation time or by using adenine in the anticoagulant. 4. A 4 hour prestorage of the whole blood unit prior to centrifugation strongly decreases the activation of platelets upon stimuli and results in platelet concentrates much more stable to storage.

Blood Platelets↗
PubMed2001

Characterization of morphological and cytoskeletal changes in MCF10A breast epithelial cells plated on laminin-5: comparison with breast cancer cell line MCF7.

The extracellular matrix regulates functional and morphological differentiation of mammary epithelial cells both in vivo and in culture. The MCF10A human breast epithelial cell line is ideal for studying these processes because it retains many characteristics of normal breast epithelium. We describe a distinct set of morphological changes occurring in MCF10A cells plated on laminin-5, a component of the breast gland basement membrane extracellular matrix. MCF10A cells adhere and spread on laminin-5 about five times more rapidly than on fibronectin or uncoated surfaces. Within 10 minutes from plating on laminin-5, they send out microfilament-rich filopodia and by 30 minutes acquire a cobblestone appearance with microfilaments distributed around the cell periphery. At 90 minutes, with or without serum, > 75% of the MCF10A cells plated on laminin-5 remain in this stationary cobblestone phenotype, while the remainder takes on a motile appearance. Even after 18 hours, when the culture is likely entering an exponential growth phase, the majority of cells maintain a stationary cobblestone appearance, though motile cells have proportionally increased. In contrast, the fully transformed, malignant human breast epithelial cells, MCF7, never acquire a stationary cobblestone appearance, do not organize peripheral microfilaments, and throughout the early time points up to 120 min appear to be constantly motile on laminin-5. We propose that changes in morphology and microfilament organization in response to laminin-5 may represent a benchmark for distinguishing normal vs. malignant behavior of epithelial cells derived from the mammary gland. This may lead to better model systems for studying the interactions between breast epithelium and the basement membrane extracellular matrix, which appear to be deregulated in processes like carcinogenesis and metastasis.

Breast↗
PubMed2004

Preterm as compared with full-term neonatal calves are characterized by morphological and functional immaturity of the small intestine.

Intestinal diseases in neonatal calves may be due to morphological and functional immaturity. We have studied histomorphology, crypt cell proliferation rates (based on incorporation of 5-bromo-2'-deoxyuridine into DNA), presence of apoptotic cells (based on terminal deoxynucleotidyl transferase-mediated X-dUTP nick end labeling), and brush border enzyme activities in preterm calves (277 d of gestation), euthanized on d 1 (P0) or 8 (P8), and in full-term calves (290 d of gestation), euthanized on d 1 (F0) or 8 (F8). Vacuolated epithelial cells were present in ileum of P0 and F0 but not in P8 and F8. During the first 8 d, villus sizes, crypt depths, and proliferation rates of crypt cells in the small intestine of preterm calves did not significantly change. In contrast, in full-term calves during the first 8 d, villus sizes in jejunum decreased, crypt depths increased in small intestine and colon, and crypt cell proliferation increased in duodenum and jejunum. Submucosal thickness in jejunum was highest in P0, but in ileum it increased with gestational age and feeding. Gestational age x feeding interactions indicated increased activities of aminopeptidase N and reduced lactase activities only in F8 and reduced dipeptidylpeptidase IV activities only in P8. In conclusion, in preterm calves the small intestinal epithelium was immature and brush border enzyme activities differed in part from those in full-term calves.

Animals↗
PubMed2002

Immune cells in the porcine retina: distribution, characterization and morphological features.

PURPOSE: To investigate the presence of immunocompetent cells in the porcine retina and to compare the findings with those obtained earlier in human retinas. METHODS: Retinal wholemounts or cryostat sections from outbred Dutch Landrace pigs were analyzed for the presence of microglia (CD45), macrophages-monocytes (SW3, CD163, 2A10, CD14), major histocompatibility complex (MHC) class II-positive cells (MCA1335), granulocytes (MCA1219), B lymphocytes (IgM), and T lymphocytes (CD6, CD4, CD8), by using specific monoclonal antibodies followed by immunohistochemical staining. RESULTS: A uniform distribution of CD45-positive microglial cells was observed throughout the porcine retina (mean number, 289 +/- 16 cells/mm(2)). The microglia were observed along blood vessels and within the tissue between the inner limiting membrane and the inner nuclear layer. MHC class II-positive cells were mainly observed along the large- and middle-sized retinal blood vessels. Double-staining experiments showed that 54% of the microglial cells lining the larger retinal vessels were MHC class II positive. Macrophages were only incidentally observed along the larger retinal blood vessels. No T lymphocytes, B lymphocytes, monocytes, or granulocytes were observed within the retinal tissue. CONCLUSIONS: The porcine retina contains a rich network of microglial cells. Approximately half of the microglial cells lining the larger retinal vessels express MHC class II. The normal porcine retina is devoid of lymphocytes, monocytes, and granulocytes. The distribution of immunocompetent cells in the porcine retina largely resembles that observed in the human retina.

Animals↗
PubMed2002

Characterization of morphology and angiogenesis in follicles of mares during spring transition and the breeding season.

The mare is a seasonal breeder and undergoes a period of ovarian transition in spring between winter anoestrus and cyclicity. During spring transition LH concentrations are low and many mares have successive large anovulatory follicular waves which reach the size of preovulatory follicles. Follicular angiogenesis is essential for growth and health of preovulatory follicles. The aim of the present study was to investigate the morphology and vascularity of transitional anovulatory follicles. On gross inspection, the wall of transitional follicles was visibly less well vascularized than that of preovulatory follicles. Histologically, it could be seen that the theca was only poorly developed in transitional follicles. Immunostaining for factor VIII showed that there were significantly (P < 0.05) fewer blood vessels in the theca of transitional follicles. There was substantially less (P < 0.001) proliferative activity, measured by immunostaining for Ki67, in the endothelial cells and granulosa cells of transitional follicles compared with preovulatory follicles. Preovulatory follicles had a heavy band of immunostaining in the theca for vascular endothelial growth factor (VEGF), whereas staining was sparse in the transitional follicles. It was concluded that the poor vascularity and development of the theca layer in transitional follicles could be related to low circulating LH, and possibly other trophic hormones, and are likely to be the key factors in explaining the steroidogenic incompetence of transitional anovulatory follicles.

Anestrus↗
PubMed1984

Morphologic-histochemical characterization of inflammatory cells in insulitis induced by multiple subdiabetogenic doses of streptozotocin in C57B1/KsJ mice.

Insulitis can be induced in C57B1/KsJ mice by injection of subdiabetogenic doses of streptozotocin (SZ, 40 mg/kg body weight) on five consecutive days. Subsequent to the resulting insulitis, a persisting diabetes syndrome develops. This experimental diabetes is regarded as a model of insulin-dependent diabetes mellitus in man (IDDM, type I). Insulitis is considered as a cellular immune reaction against the beta cells in the islets of Langerhans. This paper describes an ultrastructural study showing that lymphoid cells destroy the outer membranes of beta cells. No histochemical indications of the presence of T lymphocytes were found. Some of the lymphocytes are characterized as natural killer cells (NK cells) according to their histochemical and ultrastructural features.

Animals↗
PubMed1994

Characterization of morphological and histochemical changes induced by overexpression of P-glycoprotein in mouse leukemic cell line L1210.

Vincristine sensitive (L1210) and resistant (L1210/VCR) L1210 mouse leukemia cells were studied from morphological and histochemical point of view. The morphological and histochemical findings reflected differences in membrane structure and in physiological state of sensitive and resistant cells. Numerous villous projections and cytoplasmic protrusions of the cell surface as well as higher activity of membrane enzymes (5'-nucleotidase, ATPase, alkaline phosphatase) were found in vincristine resistant cells. It is assumed that in resistant cells these differences are connected with overexpression of membrane P-glycoprotein. Moreover, in resistant cells more condensed mitochondria were found after their exposure to vincristine. This finding can reflect a higher activity of these organelles in conditions when activity of P-glycoprotein is manifested and is in agreement with increased rate of oxygen consumption by resistant cells from 2.5 +/- 0.3 to 3.3 +/- 0.2 microliter/min.10(6) cells induced by vincristine.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1993

[Characterization of morphologic, cytochemical and immunological features in myeloperoxidase negative acute myeloid leukaemia].

Ten cases of acute myeloperoxidase-negative myeloid leukaemia (AML) were reported. They had no typical mopholocid negative for lymphocic features and were negative antigens. However 5 cases were positive for NSE/NaF stain. 9 of the 10 cases expressed more than one myeloid antigens. The authors are of the opinion that it is very difficult to diagnose myeloperoxidase-negative AML and combination of cytochemical and immunological techniques is recommended in this respect.

Adolescent↗
PubMedDate not supplied

[Comparative characterization of morphologic changes in animal brain after normo-, hypobaric hypoxic hypoxia and hypobaric normoxia].

In three series of experiments on 16 randomly inbred adult male rats, specific features of morphological changes in the brain were studied 3 days following the tests of animals for high- or low-resistance to hypoxic hypoxia (HH) during hypobaric HH (Series I), normobaric HH (Series II), and hypobaric normoxia (Series III). The conventional testing was found to result in changes in the rat brain, which were caused both by HH and decompression. The more sparing procedure is testing animal during normobaric HH which eliminates the impact of decompression whose damaging action was pronounced in hypobaric normoxia. Thus, the sensitivity of rats to HH should be detected, by using the least brain-traumatizing modified procedure--normobaric HH.

Altitude↗
PubMed2004

Moving fronts in entangled polymeric films.

Thin liquid films can become structurally unstable and dewet, forming holes which subsequently grow on the substrate. Considerable research has been conducted on the structural evolution and growth of holes, which invariably are shown to be circular. We show that morphologies characterized by circular holes comprise one of three possible morphological regimes. In polystyrene films, supported by silicon oxide substrates, two other regimes are observed with decreasing film thickness. In the second regime, the moving boundary of the growing hole may become unstable and form fingers. The spacing between the fingers is characterized by a well-defined wavelength lambda proportional to h(7/6) M(-1/2) , where h is the film thickness and M is the molecular weight. A dense branchlike morphology characterizes the peripheral regions of the holes in the third regime and is found only in the thinnest films.

Journal Article↗
PubMed1999

Apoptotic nuclear morphological change without DNA fragmentation.

Apoptosis is characterized morphologically by condensation and fragmentation of nuclei and cells and biochemically by fragmentation of chromosomal DNA into nucleosomal units [1]. CAD, also known as CPAN or DFF-40, is a DNase that can be activated by caspases [2] [3] [4] [5] [6]. CAD is complexed with its inhibitor, ICAD, in growing, non-apoptotic cells [2] [7]. Caspases that are activated by apoptotic stimuli [8] cleave ICAD. CAD, thus released from ICAD, digests chromosomal DNA into nucleosomal units [2] [3]. Here, we examine whether nuclear morphological changes induced by apoptotic stimuli are caused by the degradation of chromosomal DNA. Human T-cell lymphoma Jurkat cells, as well as their transformants expressing caspase-resistant ICAD, were treated with staurosporine. The chromosomal DNA in Jurkat cells underwent fragmentation into nucleosomal units, which was preceded by large-scale chromatin fragmentation (50-200 kb). The chromosomal DNA in cells expressing caspase-resistant ICAD remained intact after treatment with staurosporine but their chromatin condensed as found in parental Jurkat cells. These results indicate that large-scale chromatin fragmentation and nucleosomal DNA fragmentation are caused by an ICAD-inhibitable DNase, most probably CAD, whereas chromatin condensation during apoptosis is controlled, at least in part, independently from the degradation of chromosomal DNA.

Apoptosis↗
PubMed1991

Sensory neurons and motoneurons of the jaw-closing reflex pathway in rats: a combined morphological and physiological study using the intracellular horseradish peroxidase technique.

Motoneurons and muscle spindle afferents of the rat masseter muscle were physiologically and morphologically characterized. Their soma-dendritic morphology and axonal course were investigated using the intracellular horseradish peroxidase method. Following electrical stimulation of the masseter nerve, individual motoneurons were identified by antidromic all-or-none action potentials and individual sensory neurons by orthodromic action potentials. Using threshold separation an excitatory input from muscle spindles to a masseter motoneuron was demonstrated. The short latency difference of 0.34 ms between the mean orthodromic response in the sensory neurons and the beginning of the synaptic potential in the masseter motoneuron suggests a monosynaptic connection between the spindle afferents and the motoneurons. Following intrasomatic horseradish peroxidase injection large multipolar cell bodies of masseter motoneurons were found within the motor nucleus. Their positions corresponded to the topographic organization of the motor trigeminal nucleus as described in retrograde tracing studies. Dendrites of masseter motoneurons were complex and could be found far beyond the nuclear borders. Distal dendrites extended to the mesencephalic trigeminal nucleus, the supratrigeminal nucleus, the lateral lemniscus and the reticular formation. Within the reticular formation dendrites were seen in the intertrigeminal nucleus and the peritrigeminal zone. Unipolar cell bodies of muscle spindle afferents were found in the mesencephalic trigeminal nucleus after intra-axonal injection of horseradish peroxidase. For all reconstructed sensory neurons a similar axonal course was found. Axonal terminals were found ipsilateral in the motor trigeminal nucleus, indicating a direct connection between sensory neurons and motoneurons. Further collaterals were found ipsilateral in the supratrigeminal nucleus and caudal to the motor trigeminal nucleus in the parvocellular reticular nucleus alpha. Since the latter termination areas are important for bilateral control of jaw-movements, the muscle spindle afferents are likely to participate not only in a monosynaptic motor reflex, but also in more complex neuronal circuits involved in jaw-movements.

Action Potentials↗
PubMed1988

Influenza virus-model membrane interaction. A morphological approach using modern cryotechniques.

The membrane fusion activity of influenza virus was characterized morphologically using a model system composed of a highly purified influenza B virus suspension and ganglioside-containing zwitterionic liposomes. Electron microscopical analysis was performed after a combination of fast-freezing with either freeze-fracture or freeze-substitution-thin sectioning, ensuring maximal time resolution and avoiding preparation artifacts. In a parallel fluorescence 'lipid mixing' fusion assay, influenza virus-membrane fusion was characterized biochemically. Biochemical and morphological data are in full agreement, indicating negligible membrane fusion activity at neutral pH and high fusion activity at low pH. The freeze-fracture morphology strongly suggests a local point contact between viral and liposomal membrane at neutral pH, and a local point fusion mechanism for influenza virus-membrane fusion upon lowering of the pH. Fusion is followed by lipid mixing, lateral diffusion of viral spike proteins and exposure of viral contents at the inner liposomal surface.

Freeze Fracturing↗