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1.
Obstet Gynecol ; 59(2): 259-62, 1982 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7200590

RESUMEN

Two cases of herpetic endometritis are reported. In both patients, the disease developed from documented herpetic cervicitis via transcervical ascension. One patient recovered spontaneously. Generalization and death occurred in the other patient, a renal transplant recipient treated with immunosuppressive agents. The histologic features of herpetic endometritis are illustrated. Intranuclear inclusions and ground-glass nuclei were found in endometrial glandular and stromal cells. Focal necrosis was prominent. Herpetic virus particles were demonstrated by electron microscopy in both cases. Ascending herpetic endometritis is a rare complication of a common disease. In patients with deficiencies of the immune system, herpetic endometritis may represent the initial step toward dissemination and warrants particular attention.


Asunto(s)
Endometritis/diagnóstico , Herpes Genital/diagnóstico , Adulto , Endometritis/etiología , Endometritis/patología , Endometrio/patología , Femenino , Herpes Genital/patología , Humanos , Masculino
2.
J Med Microbiol ; 21(2): 151-9, 1986 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3512841

RESUMEN

Inbred female C3H mice were given 2 X 10(7) cfu virulent Salmonella typhimurium by intraperitoneal injection. Peritoneal washings were harvested between 3 h and 72 h after infection and examined by electronmicroscopy. There was evidence of intracellular killing by polymorphs and macrophages. The degeneration of intracellular salmonellae was seen initially as enlarging central electron-lucent areas in the cytoplasm and peripheral condensation of cytoplasmic granules, followed by disruption of the bacterial envelope and disintegration of cellular structure. Alternatively, the initial injury appeared as an irregular and discontinuous bacterial envelope with compression of the bacterium and diffuse condensation of cytoplasmic granules. It was also evident that virulent salmonellae multiplied extracellularly in the peritoneal cavity of the infected mice.


Asunto(s)
Macrófagos/microbiología , Neutrófilos/microbiología , Salmonelosis Animal/microbiología , Salmonella typhimurium/ultraestructura , Animales , Membrana Celular/ultraestructura , Citoplasma/ultraestructura , Gránulos Citoplasmáticos/ultraestructura , Femenino , Macrófagos/inmunología , Macrófagos/ultraestructura , Ratones , Ratones Endogámicos C3H , Microscopía Electrónica , Neutrófilos/inmunología , Neutrófilos/ultraestructura , Cavidad Peritoneal/microbiología , Fagocitosis , Fagosomas/ultraestructura , Salmonelosis Animal/inmunología , Salmonella typhimurium/crecimiento & desarrollo , Salmonella typhimurium/fisiología , Vacuolas/ultraestructura
3.
J Med Microbiol ; 22(4): 343-9, 1986 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3540305

RESUMEN

Inbred female C3H mice were given, by intraperitoneal injection, 4 X 10(7) virulent Salmonella typhimurium organisms opsonised with specific antiserum. Peritoneal washings were obtained between 1.5 and 24 h after injection and examined by electronmicroscopy. Opsonised salmonellae were ingested rapidly by peritoneal exudate cells and were digested rapidly. The presence of antibody facilitated the phagocytic efficiency of the host cells. Destruction of ingested bacteria appeared to be an innate capacity of the host phagocytes independent of the presence of antibody.


Asunto(s)
Sueros Inmunes/inmunología , Proteínas Opsoninas/inmunología , Fagocitos/inmunología , Salmonelosis Animal/inmunología , Salmonella typhimurium/inmunología , Animales , Anticuerpos Antibacterianos/inmunología , Citoplasma/ultraestructura , Eosinófilos/inmunología , Eosinófilos/microbiología , Eosinófilos/ultraestructura , Femenino , Macrófagos/inmunología , Macrófagos/microbiología , Macrófagos/ultraestructura , Ratones , Ratones Endogámicos C3H , Microscopía Electrónica , Neutrófilos/inmunología , Neutrófilos/microbiología , Neutrófilos/ultraestructura , Fagocitos/microbiología , Fagocitos/ultraestructura , Fagocitosis , Fagosomas/ultraestructura , Salmonella typhimurium/ultraestructura
4.
J Med Microbiol ; 30(1): 79-87, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2674447

RESUMEN

Virulent Salmonella typhimurium, 2000 LD50, were injected intraperitoneally into inbred male A/J mice, genetically resistant to salmonella infection. Peritoneal exudate cells were harvested between 5 and 54 h after infection and examined by electronmicroscopy. Polymorphs were seen ingesting as well as digesting the pathogens as early as 5 h after infection. Macrophages were equally active in destroying the phagocytosed organisms throughout this period. In the meantime, the proliferation of salmonellae appeared to occur extracellularly in the peritoneal cavity as evidenced by their division.


Asunto(s)
Eosinófilos/microbiología , Inmunidad Innata , Macrófagos/microbiología , Ratones Endogámicos A/inmunología , Neutrófilos/microbiología , Salmonella typhimurium/patogenicidad , Animales , Eosinófilos/ultraestructura , Macrófagos/ultraestructura , Masculino , Ratones , Ratones Endogámicos A/genética , Microscopía Electrónica , Neutrófilos/ultraestructura , Fagocitosis , Salmonella typhimurium/ultraestructura , Virulencia
5.
J Med Microbiol ; 25(1): 41-7, 1988 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3275783

RESUMEN

Highly susceptible inbred male C57BL/6 mice were infected intraperitoneally with 2 x 10(7) cfu of a virulent Salmonella typhimurium strain. Tissue sections were taken from the spleen 2 and 3 days after infection for examination by electronmicroscopy. Rapid infiltration of polymorphs and macrophages was evident at the site of infection. These inflammatory phagocytes displayed avid destructive action against ingested bacteria. Bacterial multiplication occurred primarily in extracellular locations within sinusoids or in lesions containing disintegrating host cells.


Asunto(s)
Salmonelosis Animal/microbiología , Salmonella typhimurium/crecimiento & desarrollo , Bazo/microbiología , Animales , Macrófagos/inmunología , Macrófagos/microbiología , Macrófagos/ultraestructura , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica , Neutrófilos/inmunología , Neutrófilos/microbiología , Neutrófilos/ultraestructura , Salmonelosis Animal/inmunología , Salmonella typhimurium/ultraestructura , Bazo/ultraestructura
6.
Toxicol Lett ; 90(2-3): 133-44, 1997 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-9067481

RESUMEN

In addition to its use as a stabilizer/rigidifier of membranes, cholesteryl hemisuccinate, tris salt (CS) administration has also been shown to protect rats from the hepatotoxic effects of carbon tetrachloride (CCl4). To further our understanding of the mechanism of CS cytoprotection, we examined in rats and mice the protective abilities of CS and the non-hydrolyzable ether form of CS, gamma-cholesteryloxybutyric acid, tris salt (CSE) against acetaminophen-, adriamycin-, carbon tetrachloride-, chloroform- and galactosamine-induced toxicity. The results of these studies demonstrated that CS-mediated protection is not selective for a particular species, organ system or toxic chemical. A 24-h pretreatment of both rats and mice with a single dose of CS (100mg/kg, i.p.), resulted in significant protection against the hepatotoxic effects of CCl4, CHCl3, acetaminophen and galactosamine and against the lethal (and presumably cardiotoxic) effect of adriamycin administration. Maximal CS-mediated protection was observed in experimental animals pretreated 24 h prior to the toxic insult. These data suggest that CS intervenes in a critical cellular event that is an important common pathway to toxic cell death. The mechanism of CS protection does not appear to be dependent on the inhibition of chemical bioactivation to a toxic reactive intermediate (in light of the protection observed against galactosamine hepatotoxicity). However, based on the data presented, we can not exclude the possibility that CS administration inhibits chemical bioactivation. Our findings do suggest that CS-mediated protection is dependent on the action of the intact anionic CS molecule (non-hydrolyzable CSE was as protective as CS), whose mechanism has yet to be defined.


Asunto(s)
Acetaminofén/toxicidad , Tetracloruro de Carbono/toxicidad , Cloroformo/toxicidad , Ésteres del Colesterol/uso terapéutico , Doxorrubicina/toxicidad , Galactosamina/toxicidad , Hepatopatías/prevención & control , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Cardiopatías/inducido químicamente , Cardiopatías/patología , Cardiopatías/prevención & control , Hepatopatías/metabolismo , Masculino , Ratones , Ratones Endogámicos ICR , Ratas , Ratas Sprague-Dawley
7.
Toxicol In Vitro ; 10(4): 383-93, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20650219

RESUMEN

Tacrine (tetrahydroaminoacridine, THA) is currently administered to thousands of patients for the treatment of Alzheimer's disease. Unfortunately, THA therapy is often limited by this drugs' propensity to induce reversible hepatotoxicity. In the present study we investigated the mechanism of THA cytotoxicity by measuring the effect of THA on cell viability, protein synthesis activity and the induction of apoptosis in suspensions of freshly isolated rat hepatocytes. Our experimental findings indicate that THA-mediated apoptosis is responsible for the acutein vitro hepatotoxicity observed with this aminoacridine derivative. We found that THA-treated hepatocytes (0.1, 0.25 and 0.5 mm) demonstrated a significant and dose-dependent reduction in cellular protein synthesis activity (84, 55 and 5% of control activity, respectively) after 1 hr of incubation. However, in hepatocytes exposed to 0.1 and 0.25 mm THA, the inhibition of protein synthesis was short-lived. In these treated cells, protein synthesis activity returned to control levels (100%) by the fifth hr of incubation without a significant increase in cellular lactate dehydrogenase (LDH) leakage or the induction of apoptosis. In hepatocytes exposed to 0.5 mm THA, the near complete inhibition of protein synthesis was not reversible and a dramatic increase in LDH leakage (necrosis) was observed after 6 hr of treatment. In 0.5 mm THA-treated hepatocytes the appearance of apoptotic nuclei and cells were observed with electron microscopy following 2 hr of treatment (12% of total hepatocytes analysed) and steadily increased to 42% by the fifth hr (compared with 4% for control cells). We speculate that THA's ability to inhibit hepatocyte protein synthesis (>50%) and induce apoptosis may have an important role in the hepatotoxic episodes experienced by Alzheimer's patients taking this drug. However, the role of apoptosis in clinical THA-induced hepatotoxicity and the relevance of using rat hepatocyte suspensions as anin vitro model for THA hepatotoxictyin vivo require additional investigation.

8.
Acta Cytol ; 26(6): 793-6, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-6760645

RESUMEN

Fine needle aspiration biopsy of cold thyroid nodules has become increasingly popular in determining neoplastic versus nonneoplastic conditions. The differential diagnosis between follicular adenoma and low-grade follicular carcinoma has not been consistently attainable, however; adenomatous goiter also may present problems in diagnosis, while papillary carcinoma seldom proves to be a difficult diagnosis. Image analysis, utilizing the Videoplan image analysis system, was performed on fine needle aspiration biopsy smears from these four types of nodules. The nuclear area, maximum diameter, minimal diameter and approximation to a circle were determined for 25 randomly selected cells with intact nuclei in each smear. These values were calculated with a range and standard deviation and were graphed for each parameter by case category. Cytoplasmic measurements could not be performed due to the absence of definite cytoplasmic boundaries. There was no significant difference in mean nuclear area between follicular adenoma, follicular carcinoma and adenomatous goiter. Papillary carcinoma was the only lesion to show any difference with this single parameter. The mean of maximum and minimum diameter and approximation to a circle were similar for all the types of thyroid masses examined in this study. The Videoplan image analysis system provided an efficient and accurate means of obtaining the nuclear measurements and calculating the statistics. These data illustrate that a differential diagnosis between follicular adenoma, follicular carcinoma and adenomatous goiter, while difficult by light microscopy, is not aided by image analysis of individual cell nuclei.


Asunto(s)
Bocio/diagnóstico , Enfermedades de la Tiroides/diagnóstico , Neoplasias de la Tiroides/diagnóstico , Adenocarcinoma/diagnóstico , Adenoma/diagnóstico , Biopsia con Aguja , Carcinoma Papilar/diagnóstico , Núcleo Celular/ultraestructura , Técnicas Citológicas , Diagnóstico Diferencial , Humanos , Microscopía , Enfermedades de la Tiroides/patología , Neoplasias de la Tiroides/patología
9.
Am J Pathol ; 145(2): 375-83, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8053495

RESUMEN

Cholangiolar-like structures composed of biliary epithelial cells and typically a single ductular hepatocytic cell in various stages of maturation appeared in association with an extensive bile ductular reaction within the atrophied right liver lobe of young adult Fischer 344 rats that had been subjected to a severely hepatotoxic treatment with furan. In contrast to normal cholangioles, these cholangiolar-like structures were completely surrounded by a basement membrane, which gave strong immunohistochemical staining reactions for both laminin and type IV collagen. All of the biliary epithelial cells and ductular hepatocytic cells exhibited a strongly positive immunohistochemical staining for gamma-glutamyl transpeptidase and for cytokeratin 8. Cytokeratin 19 was also strongly expressed in all of the biliary epithelial cells, but in just some of the ductular hepatocytic cells, whereas only the latter cells were immunohistochemically positive for albumin and contained peroxisomes in their cytoplasm. Cell junctions were formed between individual ductular hepatocytic cells and adjacent biliary epithelial cells of the same cholangiolar-like structures. In this novel model of severe hepatic injury, the range of cell and nuclear diameters characterizing the ductular hepatocytic cells, together with their phenotypic features, are consistent with a differentiation of rare bile ductular-like cells to transitional ductular cells to more mature ductular hepatocytes.


Asunto(s)
Conductos Biliares/citología , Furanos/farmacología , Hígado/citología , Animales , Conductos Biliares/efectos de los fármacos , Conductos Biliares/metabolismo , Diferenciación Celular , Línea Celular , Senescencia Celular , Furanos/envenenamiento , Inmunohistoquímica , Hígado/efectos de los fármacos , Hígado/ultraestructura , Masculino , Microscopía Electrónica , Ratas , Ratas Endogámicas F344 , Albúmina Sérica/metabolismo
10.
J Infect Dis ; 162(3): 765-7, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2388002

RESUMEN

After oral surgery, a 32-year-old man developed a brain abscess. Actinomycosis was suspected due to history, clinical findings, response to penicillin therapy, and demonstration of "sulfur granules" in the surgical specimen, but anaerobic cultures were negative for Actinomyces. Aerobic cultures yielded Streptococcus sanguis and Pseudomonas cepacia. Coccoid organisms demonstrated histologically reacted positively with periodic acid-Schiff, Gomori's methenamine silver, and Brown and Brenn stains, were Ziehl-Neelsen-negative, and did not include branching filaments. Fluorescent antibody assay for Actinomyces israelii was also negative. Electron microscopy revealed cell wall morphology and pattern of cell division characteristic of gram-positive cocci. These findings led to a final diagnosis of botromycosis due to S. sanguis. This third report of cerebral botryomycosis emphasizes the differential diagnosis with actinomycosis, the association with intermittently treated jaw disease, and identification of the causative agent by histologic, immunologic, and electron microscopic methods.


Asunto(s)
Absceso Encefálico/diagnóstico , Infecciones Estreptocócicas/diagnóstico , Actinomicosis/diagnóstico , Adulto , Diagnóstico Diferencial , Humanos , Masculino , Streptococcus sanguis/ultraestructura
11.
J Pharmacol Exp Ther ; 279(3): 1470-83, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8968373

RESUMEN

This study of acetaminophen (AAP) hepatotoxicity examined whether some aspects of the highly integrated process of drug-induced toxicity involves apoptosis, in addition to necrosis in vivo; and if so, whether cholesteryl hemisuccinate (CS) pretreatment would selectively interfere with apoptotic or necrotic liver cell death. We have previously demonstrated that CS preexposure in vivo, protects hepatocellular necrosis and necrosis-related events induced by carbon tetrachloride (CCl4) administration. Our study demonstrates that administration of hepatotoxic doses of AAP (350-500 mg/kg, i.p.) to ICR mice (CD-1) results in severe liver injury leading to cell death both by necrosis and apoptosis. AAP-induced cell death was preceded by massive elevation in serum alanine aminotransferase coupled with rapid loss of large genomic DNA (2-24 hr), fragmentation of DNA in the form of a ladder (2-24 hr), apoptotic nuclear condensation at early hours (2-6 hr) followed by massive fragmentation and margination of heterochromatin at later (6-24) hours and a near total loss of glycogen in pericentral areas. Although CS (100 mg/kg, i.p.) alone had no noticeable biochemical or morphological effects, its administration before AAP (350-500 mg/kg, i.p.) abrogated histological and biochemical diagnostics of both apoptosis and necrosis. These include near total absence of loss of large genomic DNA and glycogen, and dramatic protection from escalating levels of liver injury. CS pretreatment also arrested AAP-induced ultrastructural changes typical of both apoptosis and necrosis. Histopathological examination of periodic acid-Schiff stained liver sections mirrored the biochemical and ultrastructural findings. In conclusion, this study for the first time establishes that apoptosis, in addition to necrosis, significantly contributes to AAP hepatotoxicity in vivo, and preexposure of mice to CS prevents AAP-induced hepatic apoptosis and necrosis.


Asunto(s)
Acetaminofén/farmacología , Apoptosis/efectos de los fármacos , Ésteres del Colesterol/farmacología , Hígado/efectos de los fármacos , Acetaminofén/antagonistas & inhibidores , Animales , Fragmentación del ADN , Hígado/patología , Hígado/ultraestructura , Masculino , Ratones , Microscopía Electrónica , Necrosis
12.
Br J Exp Pathol ; 68(4): 539-50, 1987 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3307884

RESUMEN

Highly susceptible inbred male C57BL/6 mice were infected with 2 X 10(7) virulent Salmonella typhimurium by intraperitoneal inoculation. Samples of the liver were removed 2 or 3 days post-infection for examination by electron microscopy. Rapid infiltration of polymorphs and macrophages was observed in the site of infection. Visual evidence is presented to confirm the destruction of salmonellae within these inflammatory phagocytes as previously reported. The proliferation of the pathogens occurred in the extracellular locations of sinusoids and early lesions, and within hepatocytes.


Asunto(s)
Hígado/microbiología , Salmonelosis Animal/microbiología , Animales , Hígado/ultraestructura , Macrófagos/microbiología , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica , Mitosis , Neutrófilos/microbiología , Fagocitosis , Salmonella typhimurium/ultraestructura
13.
Immunology ; 67(3): 394-400, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2668159

RESUMEN

A procedure was developed with which peritoneal exudate cell (PEC) preparations were fixed in a glutaraldehyde-picric acid mixture, post-fixed with osmium tetroxide, embedded in LR White resin and then stained with immunogold probe. It provided tissue sections showing both well-defined ultrastructures as well as specifically labelled Salmonella O antigens by electron microscopy. Inbred, male C57BL/6 mice were injected intraperitoneally with 2 x 10(7) virulent Salmonella typhimurium. Peritoneal exudate cells were harvested at 16 and 20 hr after infection. Disintegrating intracellular bacteria were identified as salmonellae by the immunogold markers. Deposition of gold particles in the cytoplasm of phagocytes also indicated that intracellular debris contained digested pathogen. This investigation therefore confirms previous findings of the destruction of salmonellae within inflammatory polymorphs and macrophages.


Asunto(s)
Líquido Ascítico/inmunología , Salmonelosis Animal/inmunología , Salmonella typhimurium/inmunología , Animales , Antígenos Bacterianos/análisis , Líquido Ascítico/patología , Coloides , Oro , Macrófagos/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica , Neutrófilos/inmunología
14.
Hepatology ; 20(1 Pt 1): 240-6, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7517383

RESUMEN

Tacrine (tetrahydroaminoacridine) is currently the only drug approved for the treatment of Alzheimer's disease. Unfortunately, tetrahydroaminoacridine therapy is often limited by this drug's propensity to induce reversible hepatotoxicity. Using suspensions of freshly isolated rat hepatocytes, we investigated the mechanism of tetrahydroaminoacridine cytotoxicity by examining the effect of tetrahydroaminoacridine on hepatocyte viability, protein synthesis, protein, DNA and RNA levels and ultrastructure. Our experimental findings support the explanation that tetrahydroaminoacridine-induced hepatotoxicity results from tetrahydroaminoacridine's adverse effect on protein synthesis and ribosomal structure and function. We found that viable, tetrahydroaminoacridine-treated hepatocytes (1.0 to 2.0 mmol/L or 118 to 235 micrograms/10(6) cells) demonstrated a dose-dependent and dramatic aggregation of ribosomes on endoplasmic reticulum as well as the aggregation of other nucleic acids found in the nucleus (chromatin) and in mitochondria. These electron microscopy data suggest that tetrahydroaminoacridine treatment results in severe ribosomal dysfunction. This was confirmed by the observed rapid loss of cellular RNA content (but not DNA or protein) and the rapid and complete inhibition of protein synthesis in tetrahydroaminoacridine-treated cells (lowest concentration tested was 0.5 mmol/L or 58 micrograms/10(6) cells). Thus tetrahydroaminoacridine treatment appears to aggregate hepatocellular nucleic acids, and in doing so adversely affects ribosomal function and protein synthesis. We propose that these adverse effects of exposure to tetrahydroaminoacridine are responsible for tetrahydroaminoacridine-induced hepatotoxicity.


Asunto(s)
Hígado/efectos de los fármacos , Biosíntesis de Proteínas , Tacrina/toxicidad , Animales , Supervivencia Celular/efectos de los fármacos , ADN/metabolismo , Depresión Química , Hígado/citología , Hígado/metabolismo , Masculino , ARN/metabolismo , Ratas , Ratas Sprague-Dawley , Ribosomas/efectos de los fármacos , Ribosomas/ultraestructura , Suspensiones
15.
J Bacteriol ; 171(12): 6850-2, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2687257

RESUMEN

Cell wall mannoprotein of nonpathogenic yeasts is surface exposed, since the cells are agglutinated by concanavalin A and antimannoprotein antibodies. However, nonencapsulated cells of Cryptococcus neoformans were agglutinated neither by concanavalin A nor by antimannoprotein antibodies. Immunogold electron microscopy located most mannoprotein in the inner cell wall. Chemical analysis of purified cell walls showed the lack of mannose, xylose, and galactose residues. These data indicate that cryptococcal mannoprotein recovered from the cultural supernatant is a nonstructural element of the cell wall.


Asunto(s)
Cryptococcus neoformans/ultraestructura , Cryptococcus/ultraestructura , Glicoproteínas de Membrana/análisis , Pared Celular/ultraestructura , Concanavalina A , Hemaglutinación , Sueros Inmunes , Inmunohistoquímica , Microscopía Electrónica
16.
Microvasc Res ; 41(3): 328-44, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-1649374

RESUMEN

The microcirculation contains mononuclear phagocytes, with features characteristic of macrophages, adhered to luminal capillary surfaces by intercellular adhesion plaques. These pulmonary intravascular macrophages may play an important role in regulating lung vascular tone and capillary permeability, and may modulate capillary endothelial cell growth and replication by the secretion of soluble mediators (i.e., arachidonate metabolites, cytokines). This study describes a technique which utilizes in situ lung perfusion to remove intravascular macrophages in large numbers from the microcirculation of porcine lung (n = 26). This technique yielded 3.8 +/- 0.5 x 10(8) (mean +/- SEM) mononuclear cells which were highly phagocytic toward particulate carbon (phagocytic index, 80 +/- 6%). Harvested mononuclear phagocytes reestablished intercellular adhesion plaques when placed on small vessel porcine pulmonary artery endothelial cell monolayers and exhibited histochemical characteristics typical of monocyte/macrophage lineage cells. Mononuclear cells obtained from lung microcirculation displayed size heterogeneity varying from 10.4 to 16.5 microns in diameter. Both large and small cell populations phagocytosed particulate carbon. Morphometric studies performed on collagenase-treated lung demonstrated that in situ perfusion removed significant numbers of intravascular macrophages in lung capillaries. The technique described permits the rapid removal of anchored mononuclear phagocytes from lung capillaries with minimal postmortem delay.


Asunto(s)
Separación Celular , Pulmón/irrigación sanguínea , Macrófagos , Animales , Recuento de Células , Separación Celular/métodos , Histocitoquímica , Pulmón/citología , Pulmón/efectos de los fármacos , Macrófagos/química , Macrófagos/fisiología , Macrófagos/ultraestructura , Colagenasa Microbiana/farmacología , Microcirculación , Perfusión , Fagocitosis , Porcinos
17.
Cell Growth Differ ; 5(7): 723-33, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7947387

RESUMEN

The effects on DNA integrity of continuous (72-h) exposure of human MCF-7 breast adenocarcinoma cells to 50 nM doxorubicin (a concentration which can be maintained in the plasma by continuous infusion) were characterized by bisbenzimide spectrofluorophotometry, cell flow cytometry, agarose gel electrophoresis, and neutral elution. Spectrofluorophotometry and cell flow cytometry indicated the presence of DNA fragmentation, which was maximal at 24 h. Resolution of these fragments on agarose gels failed to demonstrate "laddered" oligosomal profiles. Neutral elution analysis at 24 h indicated that doxorubicin induced fragmentation of nascent, but not mature, double-stranded DNA. Drug-treated cells exhibited endoreduplication and significant shifts in cell cycle distribution, (i.e., increased G0/G1 and G2/M fractions and a markedly reduced S-phase fraction). These alterations occurred without inhibiting the incorporation of [3H]dThd into cellular DNA; in fact, both the rate and magnitude of [3H]dThd incorporation increased progressively. Doxorubicin also produced a sustained decline in c-myc mRNA levels that paralleled both growth arrest and induction of DNA fragmentation. Ultrastructural examination revealed morphological alterations consistent with the induction of differentiation (e.g., increased lipid content and mitochondrial density, appearance of tight junctions, and secretory ducts) and further suggested the possibility of autocatalysis (e.g., lipofuschin-containing vacuoles). A gradual decline in cell number was observed, with loss of approximately 35% of the cell population after 72 h.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Adenocarcinoma/patología , Neoplasias de la Mama/patología , ADN de Neoplasias/efectos de los fármacos , Doxorrubicina/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Proteínas de Neoplasias/biosíntesis , Proteínas Proto-Oncogénicas c-myc/biosíntesis , Apoptosis , Ciclo Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Daño del ADN , Femenino , Genes myc/efectos de los fármacos , Humanos , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogénicas c-myc/genética , Células Tumorales Cultivadas
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