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1.
Opt Express ; 17(14): 11834-49, 2009 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-19582098

RESUMEN

Photorefractive materials are dynamic holographic storage media that are highly sensitive to coherent light fields and relatively insensitive to a uniform light background. This can be exploited to effectively separate ballistic light from multiply-scattered light when imaging through turbid media. We developed a highly sensitive photorefractive polymer composite and incorporated it into a holographic optical coherence imaging system. This approach combines the advantages of coherence-domain imaging with the benefits of holography to form a high-speed wide-field imaging technique. By using coherence-gated holography, image-bearing ballistic light can be captured in real-time without computed tomography. We analyzed the implications of Fourier-domain and image-domain holography on the field of view and image resolution for a transmission recording geometry, and demonstrate holographic depth-resolved imaging of tumor spheroids with 12 microm axial and 10 microm lateral resolution, achieving a data acquisition speed of 8 x 10(5) voxels/s.


Asunto(s)
Diagnóstico por Imagen/instrumentación , Holografía/métodos , Imagenología Tridimensional/instrumentación , Animales , Biopsia/instrumentación , Biopsia/métodos , Diagnóstico por Imagen/métodos , Diseño de Equipo , Análisis de Fourier , Holografía/instrumentación , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Luz , Óptica y Fotónica , Osteosarcoma/patología , Polímeros/química , Ratas , Tomografía de Coherencia Óptica/instrumentación , Tomografía de Coherencia Óptica/métodos
2.
J Leukoc Biol ; 56(5): 599-604, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7964168

RESUMEN

The effects of various dietary polyunsaturated fatty acids (PUFAs) on the function of immune cells of the porcine lung was studied. Groups of six pigs were fed diets containing 10.5% corn oil [CO; enriched in linoleic acid (18:2, n-6)], linseed oil (LO; enriched in alpha-linolenic acid (18:3, n-3)], menhaden oil (MO; enriched in eicosapentaenoic (20:5; n-3) and docosahexaenoic (22:6; n-3) acids], linseed + corn oil (1:1; LC), and menhaden + corn oil (1:1; MC) for 28-30 days. Basal levels of alveolar macrophage (m phi) tumor necrosis factor-alpha (TNF-alpha) production were higher (P < .05) for LC- and MC-fed pigs than for CO- and LO-fed pigs. Lipopolysaccharide (LPS)-stimulated LC and MC m phi s produced more TNF than m phi s from pigs fed CO, LO, and MO diets. Macrophages from pigs receiving the CO and LC diets had higher (P < .05) levels of leucine aminopeptidase than m phi s from the other dietary groups. Lipopolysaccharide did not increase m phi nitrite production over basal levels except in the MO diet group. However, LPS-stimulated m phi s from the CO, MO, and LC dietary groups produced more nitrite than m phi s from MC-fed pigs. Alveolar lymphocytes from pigs receiving the MC diet produced more T cell growth factors than LO and MO m phi s. Alveolar m phi s from the different dietary groups did not differ in their capacity for non-immune-mediated phagocytosis of fluorescent latex beads. These results indicate that dietary PUFAs can modulate some functions of porcine alveolar immune cells and that this may prove significant for host response to respiratory disease agents.


Asunto(s)
Grasas Insaturadas en la Dieta/farmacología , Pulmón/inmunología , Macrófagos Alveolares/metabolismo , Animales , Interleucina-2/metabolismo , Leucil Aminopeptidasa/metabolismo , Macrófagos Alveolares/efectos de los fármacos , Masculino , Nitritos/metabolismo , Fagocitosis/efectos de los fármacos , Organismos Libres de Patógenos Específicos , Porcinos , Linfocitos T/metabolismo , Factor de Necrosis Tumoral alfa/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismo
3.
Artículo en Inglés | MEDLINE | ID: mdl-27280042

RESUMEN

Biodynamic imaging (BDI) is a novel phenotypic cancer profiling technology which optically characterizes changes in subcellular motion within living tumor tissue samples in response to ex vivo treatment with cancer chemotherapy drugs. The purpose of this preliminary study was to assess the ability of ex vivo BDI to predict in vivo clinical response to chemotherapy in ten dogs with naturally-occurring non-Hodgkin's lymphomas. Pre-treatment tumor biopsy samples were obtained from all dogs and treated ex vivo with doxorubicin (10 µM). BDI measured six dynamic biomarkers of subcellular motion from all biopsy samples at baseline and at regular intervals for 9 h following drug application. All dogs subsequently received doxorubicin to treat their lymphomas. Best overall response to and progression-free survival time following chemotherapy were recorded for all dogs. Receiver operating characteristic (ROC) curves were used to determine accuracy and identify possible cut-off values for the BDI-measured biomarkers which could accurately predict those dogs' cancers that would and would not respond to doxorubicin chemotherapy. One biomarker (designated 'MEM') showed 100% discriminative capability for predicting clinical response to doxorubicin (area under the ROC curve = 1.00, 95% CI 0.692-1.000), while other biomarkers also showed promising predictive capability. These preliminary findings suggest that ex vivo BDI can accurately predict treatment outcome following doxorubicin chemotherapy in a spontaneous animal cancer model, and is worthy of further investigation as a technology for personalized cancer medicine.

4.
J Nucl Med ; 39(9): 1579-85, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9744347

RESUMEN

UNLABELLED: Indium-111-labeled diethylenetriamine pentaacetic acid (DTPA)-folate was evaluated as a radiopharmaceutical for targeting tumor-associated folate receptors. METHODS: Athymic mice were subcutaneously inoculated with approximately 1.8 x 10(6) folate receptor-positive KB (human nasopharyngeal carcinoma) cells, yielding 0.2- to 0.6-g tumors in 15 days, at which time (111)In-DTPA-folate, (111)In-DTPA or (111)In-citrate was administered by intravenous injection. RESULTS: The (111)In-DTPA-folate conjugate afforded marked tumor-specific (111)In deposition in vivo using this mouse model. The involvement of the folate receptor in mediating tumor uptake of (111)In-DTPA-folate was demonstrated by the blocking of tumor uptake by coadministration of free folic acid (intravenous). The (111)In-DTPA-folate also shows folate receptor-mediated uptake and retention in the kidneys, presumably reflecting radiotracer binding to folate receptors of the proximal tubules. In control experiments, the (111)In-citrate radiopharmaceutical precursor was also shown to afford significant tumor uptake of (111)In, but with much poorer tumor-to-background tissue contrast than that obtained with (111)In-DTPA-folate. Unconjugated (111)In-DTPA showed no tumor affinity. CONCLUSION: Indium-111-DTPA-folate appears suitable as a radiopharmaceutical for targeting tumor-associated folate receptors.


Asunto(s)
Proteínas Portadoras/análisis , Ácido Fólico/análogos & derivados , Radioisótopos de Indio , Ácido Pentético/análogos & derivados , Radiofármacos , Receptores de Superficie Celular/análisis , Animales , Proteínas Portadoras/metabolismo , Estudios de Factibilidad , Receptores de Folato Anclados a GPI , Ácido Fólico/farmacocinética , Humanos , Radioisótopos de Indio/farmacocinética , Células KB , Túbulos Renales Proximales/diagnóstico por imagen , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Ácido Pentético/farmacocinética , Cintigrafía , Radiofármacos/farmacocinética , Receptores de Superficie Celular/metabolismo , Distribución Tisular
5.
Artículo en Inglés | MEDLINE | ID: mdl-8469682

RESUMEN

The purpose of this study was to determine how dietary n-3 and n-6 polyunsaturated fatty acids (PUFA) affected the gastrointestinal response to lipopolysaccharide (LPS) and indomethacin (INDO) in the rat. Rats were fed diets containing 12.5% linseed oil (LO-enriched in short-chain n-3 PUFA) or corn oil (CO-enriched in n-6 PUFA). After 30 days on the diets, rats were given one of three treatments 1:10 mg/kg O55:B5 Escherichia coli LPS intraperitoneally (i.p.), 2:25 mg/kg INDO subcutaneously (s.c.), 3: a combination of 10 mg/kg i.p. LPS and 25 mg/kg (s.c.) INDO given 30 min before LPS. 20 h after challenge, rats were given an intravenous injection of Monastral Blue B to stain ulcer areas in the gastrointestinal tract. Lipopolysaccharide did not result in any Monastral Blue B vascular leakage in the gastrointestinal tract. Rats on the LO diet had significantly increased stomach and intestinal ulcers compared to CO fed rats. When rats were challenged with LPS and INDO, the LPS almost completely eliminated small intestinal ulcers, but enhanced ulcer development in the stomach.


Asunto(s)
Enfermedades Gastrointestinales/etiología , Indometacina/toxicidad , Úlcera/etiología , Animales , Aceite de Maíz/toxicidad , Grasas Insaturadas en la Dieta/efectos adversos , Endotoxinas/toxicidad , Ácidos Grasos/toxicidad , Enfermedades Gastrointestinales/prevención & control , Aceite de Linaza/toxicidad , Lipopolisacáridos/toxicidad , Masculino , Ratas , Ratas Wistar , Úlcera/prevención & control
6.
Artículo en Inglés | MEDLINE | ID: mdl-1871180

RESUMEN

The purpose of this study was to determine the effect of dietary n-3 and n-6 fatty acids on tumor necrosis factor-alpha (TNF-alpha) production and macrophage (MO) activation state. Rats were fed diets containing 12.5% linseed oil (LO) or corn oil (CO) that are high in n-3 and n-6 fatty acids respectively. The LO diet resulted in a significant increase in basal and endotoxin (LPS)-induced levels of TNF-alpha from resident MO cultured in vitro. There was no difference between the diets in LPS-induced TNF-alpha production by complete Freund's adjuvant (CFA) elicited macrophages. Variable responses were also observed between LO and CO MO in response to prostaglandin E2, indomethacin (INDO), and the prostaglandin E receptor antagonist SC-19220. This may indicate differences in signal transducing secondary messengers due to different activation states, receptor expression or ligand binding. Fluorescence due to leucine aminopeptidase (LAP) staining was determined by flow cytometry. Resident LO MO had a 15% increase in LAP fluorescence compared to CO MO. In CFA-elicited MO, the CO MO had a 43% increase in fluorescence compared to LO MO. Resident LO MO increased in LAP fluorescence by 35% to the activated state whereas resident CO MO increased in LAP fluorescence by 93%. The smaller window of activation for the LO MO may explain some of the antiinflammatory properties of dietary n-3 fatty acids.


Asunto(s)
Ácidos Grasos Insaturados/farmacología , Leucil Aminopeptidasa/análisis , Macrófagos/enzimología , Factor de Necrosis Tumoral alfa/biosíntesis , Animales , Dinoprostona/análisis , Ácidos Grasos Insaturados/administración & dosificación , Citometría de Flujo , Fluorescencia , Activación de Macrófagos/efectos de los fármacos , Masculino , Cavidad Peritoneal/citología , Ratas , Ratas Endogámicas
7.
Vet Immunol Immunopathol ; 35(3-4): 239-51, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8430495

RESUMEN

Natural killer (NK) cells spontaneously lyse a variety of tumor cells in vitro, and are believed to play an important role in host resistance to tumor growth and metastasis in vivo. As part of our work in comparative oncology, we have designed and validated a canine NK cell assay. Of several lymphocyte isolation techniques evaluated, sedimentation of whole blood through a two-step Ficoll/Hypaque gradient (sp. gr. 1.066/1.119) followed by plastic adherence of monocytes resulted in the most pure lymphocyte population (> 95% lymphocytes). Of four cell lines evaluated as targets in the NK assay, a canine thyroid adenocarcinoma (CTAC) cell line was determined to be most sensitive, and a lymphoblastoid (CT45-S) cell line was determined to be most resistant to NK lysis. A 15 h effector-target incubation period using these targets resulted in reproducible measurement of cell specific lytic activity. Passage of canine lymphocytes through nylon wool columns did not result in a significant increase in NK activity. A final sedimentation of purified lymphocytes through a 45/50% Percoll gradient concentrated NK activity into a single band of lymphocytes. Lymphocytes forming conjugates with CTAC target cells were 5.5-6.5 microns in diameter, and were characterized by a reniform nucleus and varying numbers of electron-dense cytoplasmic granules.


Asunto(s)
Pruebas Inmunológicas de Citotoxicidad/métodos , Citotoxicidad Inmunológica/inmunología , Células Asesinas Naturales/inmunología , Linfocitos/inmunología , Animales , Separación Celular/métodos , Perros , Eosinófilos/inmunología , Eosinófilos/ultraestructura , Linfocitos/ultraestructura , Células Tumorales Cultivadas
8.
Vet Immunol Immunopathol ; 69(2-4): 165-83, 1999 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-10507303

RESUMEN

The focus of this study was to examine the influence of age and diet on various parameters of immune function in young and old Fox Terriers and Labrador Retrievers. Eighteen young and old dogs were utilized for this study. Young and old dogs were fed a basal diet containing an (n-6):(n-3) ratio of 25:1 for sixty days (Phase I). Half of the dogs were then switched to a diet with an (n-6):(n-3) ratio of 5:1, and all were maintained on their respective diets for an additional sixty days (Phase II). Results from these studies revealed an age-associated decline in several immune parameters measured. Both these breeds demonstrated a reduction in sheep red blood cell titers, as well as in their ability to respond to different mitogens. Interestingly, this decline was greater in Fox Terriers, suggesting a decrease in cellular proliferative capacity in lymphocytes isolated from the larger breed. Neither cytokine production or DTH response was affected by age. Diet and breed interactions resulted in a significant increase in T- and B-cell mitogen responsiveness. In contrast, supplementation with n-3 fatty acids did not affect IL-1, IL-6 or TNF-alpha production. Supplementation with n-3 fatty acids resulted in increased PGE3 production from peritoneal macrophages but had no effect on PGE2 production from peripheral blood mononuclear cells or peritoneal macrophages. The n-3 fatty acid supplementation did not influence alpha-tocopherol status although older dogs had significantly lower serum alpha-tocopherol concentrations. Oxidative status of these dogs was assessed by serum levels of malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE). Feeding an n-3-enriched diet did not affect 4-HNE levels but significantly decreased MDA levels in old dogs. In summary, this study indicates that feeding a diet containing an (n-6):(n-3) fatty acid ratio of 5:1 had a positive, rather than a negative, effect on the immune response of young or geriatric dogs.


Asunto(s)
Envejecimiento/inmunología , Grasas Insaturadas en la Dieta/farmacología , Perros/inmunología , Ácidos Grasos Omega-3/farmacología , Ácidos Grasos Insaturados/farmacología , Peroxidación de Lípido , Envejecimiento/efectos de los fármacos , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta , Ácidos Grasos Omega-6 , Hipersensibilidad Tardía/inmunología , Estrés Oxidativo
9.
Food Chem Toxicol ; 23(9): 795-803, 1985 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2931336

RESUMEN

Daily doses of 6-aminonicotinamide (3-5 mg/kg) given by ip injection produced ataxia of the hind limbs progressing to an ascending paresis/paralysis, anorexia, diarrhoea and death in male and female New Zealand White and Dutch Belted rabbits. At autopsy, caecal and gastric distention were seen and the apex of the gall bladder had necrotic foci. Light microscopic lesions included atrophy and necrosis of the white lobe of Harder's gland and atrophy of seminiferous tubules with cellular necrosis, vacuolation and the presence of multinucleated giant cells. Cytoplasmic vacuolation was observed in epithelial cells from many tissues, usually in the basal portion of the cells. Vacuolation of the epithelium of the sacculus rotundus and vermiform appendix was found within the same time frame as histiocytic hyperplasia in these organs. Spongiosis and gliosis were seen in certain parts of the central nervous system. Ultrastructural alterations in the gall bladder epithelium consisted of distention of intercellular space, mild distention of perinuclear space and coalescing, intracytoplasmic, membrane-bound vacuoles, a few of which contained membranous debris. Some alterations of 6-aminonicotinamide toxicosis were prevented by simultaneous administration of nicotinamide with 6-aminonicotinamide.


Asunto(s)
6-Aminonicotinamida/toxicidad , Necrosis/inducido químicamente , Niacinamida/análogos & derivados , Animales , Femenino , Inyecciones Intraperitoneales , Masculino , Microscopía Electrónica , Necrosis/patología , Conejos , Especificidad de la Especie
10.
Physiol Res ; 48(4): 281-9, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10638679

RESUMEN

With L-glutamine, as a representative amino acid this study was undertaken to examine the effects of substrate concentrations on initial and equilibrium amino acid uptake and intravesicular volume determined with porcine jejunal brush border membrane vesicles prepared by Mg2+-aggregation and differential centrifugation. Transport measurements (24 degrees C) were conducted by the rapid filtration manual procedure. Glutamine uptake was shown to occur into an osmotically-active space ranging between 1.09-1.58 microl/mg protein with little non-specific membrane binding. At different concentrations (in parentheses), the duration of initial glutamine uptake in both Na+ gradient and Na+-free conditions was 10 s (0.01 mM), 15 s (0.17 mM), and 20 s (1.9 and 9.4 mM), respectively. Substrate concentrations affected the duration of initial uptake, with lower substrate concentrations giving shorter duration for initial amino acid uptake. At different substrate concentrations (in parentheses), the time required to reach equilibrium glutamine uptake was 5 min (0.01 mM), 10 min (0.17 mM), and 60 min (1.9 and 9.4 mM), respectively. Thus, substrate concentrations also affected the time required to reach equilibrium uptake. The higher the substrate concentration, the longer the incubation time needed to reach equilibrium amino acid uptake. At the glutamine concentrations of 0.01, 0.17, 1.9, and 9.4 mM, the average intravesicular volume was estimated to be 1.58+/-0.21, 1.09+/-0.28, 1.24+/-0.18, and 1.36+/-0.21 microl/mg protein, respectively. Substrate concentrations had no effect (p>0.05) on the intravesicular volume of membrane vesicles. In conclusion, in the experiments on amino acid transport kinetics measured with the rapid filtration manual procedure, the incubation time used for measuring the initial uptake rate should be determined from the time course experiments conducted at the lowest substrate concentration used, whereas the intravesicular volume can be obtained from equilibrium uptake measured at any substrate concentrations.


Asunto(s)
Aminoácidos/metabolismo , Yeyuno/metabolismo , Microvellosidades/metabolismo , Porcinos/metabolismo , Animales , Transporte Biológico , Centrifugación , Glutamina/metabolismo , Cinética , Magnesio , Concentración Osmolar , Sodio
11.
J Vet Diagn Invest ; 1(2): 160-4, 1989 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2488334

RESUMEN

One hundred thirty-eight swine abortions were studied in detail in an effort to identify an etiologic agent. A viral agent was implicated in 7 cases. Bacteria were isolated in less than half of the examined cases: however, in 61% of the cases, motile, filamentous organisms were observed in tissues and fluids. Although swine sera from farms experiencing reproductive problems had a high reactor rate to Leptospira bratislava antigen, electron microscopy of the observed organism revealed a wall-free prokaryote morphologically typical of the class Mollicutes.


Asunto(s)
Aborto Veterinario/microbiología , Muerte Fetal/veterinaria , Infecciones por Spirochaetales/veterinaria , Spirochaetales/aislamiento & purificación , Enfermedades de los Porcinos/microbiología , Animales , Femenino , Muerte Fetal/microbiología , Técnica del Anticuerpo Fluorescente , Microscopía Electrónica , Embarazo , Spirochaetales/ultraestructura , Infecciones por Spirochaetales/microbiología , Spiroplasma/aislamiento & purificación , Spiroplasma/ultraestructura , Porcinos
12.
Vet Parasitol ; 31(3-4): 281-8, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2527435

RESUMEN

Scanning electron microscopy revealed that lesions of sarcoptic mange in swine, pass through 3 different stages. During the first 3 weeks of infestation, adult female mites tunnel into the epidermis. During the following 3 or 4 weeks, the surface openings of these tunnels become covered with keratinized epidermal crust which increases in thickness. After 7 weeks of infestation, the crust falls off, the tunnel openings become apparent again and most of the mites vacate these tunnels.


Asunto(s)
Escabiosis/veterinaria , Piel/ultraestructura , Enfermedades de los Porcinos/patología , Animales , Epidermis/parasitología , Epidermis/ultraestructura , Femenino , Microscopía Electrónica de Rastreo , Sarcoptes scabiei/fisiología , Sarcoptes scabiei/ultraestructura , Escabiosis/patología , Piel/parasitología , Organismos Libres de Patógenos Específicos , Porcinos , Enfermedades de los Porcinos/parasitología
13.
J Parasitol ; 68(4): 634-41, 1982 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6889644

RESUMEN

The labial organization of adult Baylisascaris procyonis was studied by scanning electron microscopy, and found to be similar for males and females. The apical part of each lip was smooth, and the basal part reticulated. The dorsal lip possessed two dorsolateral double papillae and two internal labial papillae; the two subventral lips each had one ventrolateral double and one externolateral papilla, two internal labial papillae, and an amphid. The small papilla of each double set was dome-shaped and smooth, whereas the large papilla was broad and had a prominent central pore. The externolateral papillae had raised, highly sculptured surfaces with numerous slits and creases present. Amphids resembled those of previously studied nematodes. The internal labial papillae consisted of pits. Denticles arose as a single row from the apical edge of the inner labial surface, were usually evenly spaced, and pyramidal or conoidal in shape. They were typically unicuspid, but bicuspid denticles were occasionally seen. Denticle shape and size varied between specimens and on each specimen. A pit was seen in the cuticle in the central region of the denticular row of all lips. Several of these findings represent new information concerning ascaridoid nematodes.


Asunto(s)
Ascaridoidea/ultraestructura , Animales , Ascaridoidea/clasificación , Microscopía Electrónica de Rastreo , Mapaches/parasitología
14.
J Comp Pathol ; 101(3): 351-4, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2584453

RESUMEN

Mucocutaneous histoplasmosis was diagnosed in a pet rabbit. A mass protruding through the anal opening was histologically composed of a densely cellular infiltrate of macrophages which expanded the anorectal submucosa. Macrophages contained abundant yeast forms of fungi morphologically consistent with Histoplasma capsulatum. Infection appeared to be localized. Histoplasmosis should be considered in the differential diagnosis of granulomatous inflammatory disease in the rabbit.


Asunto(s)
Histoplasmosis/veterinaria , Conejos , Animales , Enfermedades del Ano/patología , Enfermedades del Ano/veterinaria , Femenino , Histoplasmosis/patología , Macrófagos/microbiología , Macrófagos/patología , Enfermedades del Recto/patología , Enfermedades del Recto/veterinaria
15.
Exp Toxicol Pathol ; 47(6): 447-52, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8871083

RESUMEN

The ultrastructural lesions of diphenylamine-induced renal papillary necrosis in Syrian hamsters were characterized by transmission electron microscopy. Twenty-four male Syrian hamsters were orally administered 600 mg diphenylamine/kg body weight as a single dose. At 30 minutes and at 1, 2, 4, 8, 16 and 24 hours after administration of diphenylamine, three hamsters were anesthetized with pentobarbital, perfused via the left ventricle with half-strength KARNOVSKY's fixative, and the renal papilla and outer medulla collected. Three hamsters administered 0.5 ml peanut oil/kg body weight (vehicle controls) were anesthetized at 24 hours, perfused, and the renal papilla and outer medulla collected. Initial ultrastructural lesions were observed in the endothelial cells of the ascending vasa recta in the proximal portion of the renal papilla at 1 hour after diphenylamine administration. The endothelial cell basal plasma membrane was elevated from the basal lamina, forming large subendothelial vacuoles. Alterations in inner medullary interstitial cells, endothelial cells of the descending vasa recta, and the epithelial cells of the thin limbs of Henle and the medullary collecting tubules were observed subsequent to the lesion in the ascending vasa recta. It was concluded that the endothelial cell of the ascending vasa recta is the target cell in diphenylamine-induced renal papillary necrosis in Syrian hamsters.


Asunto(s)
Difenilamina/toxicidad , Necrosis Papilar Renal/inducido químicamente , Necrosis Papilar Renal/patología , Riñón/patología , Riñón/ultraestructura , Animales , Cricetinae , Masculino , Mesocricetus
16.
Int J Artif Organs ; 22(3): 177-88, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10357246

RESUMEN

The Biologic-DTPF System (DTPF), an extracorporeal blood treatment device with potential to treat sepsis, was tested in a preliminary study using a canine endotoxemia model. Six dogs were used and they formed four treatment groups, as control group (n=1) and three groups based on the type of sorbent present in the plasma filter (PF) system: sham treatment with no sorbent (n=1), charcoal as sorbent (n=2), and charcoal/silica as sorbent ("silica" group, n=2). Cardiodynamic data were recorded before treatment and every 30 minutes, and blood samples were collected to determine blood chemistry and to detect the levels of endotoxin and selected plasma cytokines: interleukin-1 (IL-1), interleukin-6 (IL-6), and tumor necrosis factor (TNF). The dogs were given Escherichia coli endotoxin (2 mg/kg) as an intravenous drip (extended over a period of 30 minutes). Thirty minutes after the end of infusion all animals except the control were treated with the DTPF system for four hours. To determine the effect of treatment, data collected at one hour from the initiation of treatment until the end of treatment were compared between control and treated dogs. The endotoxin levels in the control dog were higher (P < 0.05) than other groups. The control dog had lower levels of TNF than other groups. The control dog had similar levels of IL-1 (P > 0.05) and higher levels (P < 0.05) at 4 hours into treatment compared to other groups. The control dog had similar levels of IL-6 as other groups (P > 0.05). In the control dog, the mean arterial pressure (MAP) fell and then remained low but stable at 1-4 hours. The charcoal group had lower MAP than the control dog at 1-4 hours (P < 0.05). The silica group had higher MAP levels similar to the control dog. After treatment, the control dog had higher (P < 0.05) values of hematocrit, hemoglobin, calcium, potassium, and albumin compared to the treated groups. As expected for a system removing plasma during sepsis, the DTPF System had some adverse effects on the physiologic status of the dogs, especially when loaded with charcoal sorbent only. The findings of the present study suggest that the filters are capable of eliminating endotoxin and there is some evidence of cytokine removal. Although the charcoal dogs did poorly, addition of silica to the sorbent offset any negative effects. Further work is underway to improve the efficiency of the system, primarily to enhance the capacity of the sorbents for cytokines. A more realistic canine sepsis model with mortality after several days (the Escherichia coli- infected intraperitoneal clot) will also be considered in future studies.


Asunto(s)
Infecciones por Escherichia coli/terapia , Plasmaféresis/instrumentación , Diálisis Renal/instrumentación , Choque Séptico/terapia , Análisis de Varianza , Animales , Antídotos/uso terapéutico , Carbón Orgánico , Citocinas/sangre , Modelos Animales de Enfermedad , Perros , Endotoxinas/sangre , Diseño de Equipo , Infecciones por Escherichia coli/mortalidad , Femenino , Hemodinámica/fisiología , Masculino , Plasmaféresis/métodos , Plasmaféresis/mortalidad , Probabilidad , Valores de Referencia , Choque Séptico/sangre , Choque Séptico/mortalidad , Desintoxicación por Sorción , Tasa de Supervivencia
17.
Can J Vet Res ; 50(1): 88-95, 1986 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3742364

RESUMEN

One hundred and twenty female mice (CF1 strain) were divided into three groups of 40. The first group was injected intraperitoneally with broth cultures of Treponema hyodysenteriae. The second group was injected with a combination of T. hyodysenteriae and Bacteroides vulgatus. The third group was injected with Treponema innocens. Peritoneal wash from four mice of each group was collected at eight time intervals postinjection, then prepared for and examined by light and electron microscopy. Peritoneal wash from one mouse at each time interval was prepared for microbiological examination. Treponema hyodysenteriae produced peritoneal macrophage aggregation, transient neutrophilia and macrophage cytolysis. Cytolysis was characterized by rarefaction of the cytoplasm, vesiculation of the endoplasmic reticulum, mild swelling of the mitochondria and disruption of the nuclear and ctyoplasmic membranes. The combination of T. hyodysenteriae and B. vulgatus produced macrophage aggregation and marked neutrophil necrosis. Peritoneal macrophages phagocytized more T. hyodysenteriae than B. vulgatus during early postinjection intervals. Treponema innocens failed to produce cytotoxicity of peritoneal macrophages but did produce macrophage aggregation and transient neutrophilia. Treponema hyodysenteriae and T. innocens did not multiply in the mice peritoneal cavity and were reisolated up to 16 hours postinjection. Bacteroides vulgatus was reisolated up to 24 hours postinjection.


Asunto(s)
Bacteroides/patogenicidad , Disentería/etiología , Fagocitosis , Treponema/patogenicidad , Animales , Supervivencia Celular , Disentería/patología , Disentería/fisiopatología , Femenino , Interacciones Huésped-Parásitos , Ratones , Microscopía Electrónica , Fagocitos/microbiología , Fagocitos/fisiología , Fagocitos/ultraestructura
18.
Am J Vet Res ; 50(2): 296-300, 1989 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2524180

RESUMEN

Embryos were harvested at the blastocyst stage from nontreated outbred mice and were grown in vitro for 4 days. Embryos cultured in control medium hatched and grew to the egg cylinder stage. Purified zearalenone (ZEN) added to the culture medium at concentrations of 8.5 to 68 micrograms/ml decreased the number of embryos growing, with a 50% decrease in the number growing in 32 micrograms of ZEN/ml of medium. Embryos growing in ZEN had decreased numbers of cells derived from the inner cell mass, normal growth of the trophoblast, less cellular differentiation than was seen in control embryos, and increased numbers of phagosomes. Undifferentiated cells of the inner cell mass of control and treated embryos were of the same size, as determined by morphometric analysis. Addition of 25 micrograms of estradiol/ml of culture medium caused no decrease in number of embryos growing or in embryonic size. Saturation of culture medium with ZEN (68 micrograms/ml) did not inhibit the growth of a tissue culture line of goat synovial cells. Seemingly, ZEN at concentrations near saturation inhibited the growth of mouse embryos in vitro. This effect was not duplicated with similar concentrations of estradiol and was not manifested in culture-adapted cells.


Asunto(s)
Blastocisto/efectos de los fármacos , Embrión de Mamíferos/efectos de los fármacos , Resorcinoles/farmacología , Zearalenona/farmacología , Animales , Blastocisto/ultraestructura , Embrión de Mamíferos/fisiología , Embrión de Mamíferos/ultraestructura , Desarrollo Embrionario y Fetal/efectos de los fármacos , Femenino , Masculino , Ratones
19.
Am J Vet Res ; 48(3): 515-8, 1987 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3565908

RESUMEN

Dispersed cell cultures were established from the articular cartilage of the proximal portion of the humerus of young pigs. Articular and epiphyseal portions of the cartilage were separated, minced, and enzymatically dispersed, using bacterial collagenase. Morphologically, 2 cell types were observed, using phase-contrast microscopy. Smaller polygonal cells (32.5 +/- 3.5 microns diameter) containing cytoplasmic granules were found in both areas of the cartilage. In cultures from the articular region, cells grew as monolayer cultures and initially did not demonstrate contact inhibition. In cultures from the epiphyseal region, cells grew in a multilayered manner in a colonial arrangement with cells being released from the center of the colony into the culture medium. Small granular particles (0.03 to 0.08 micron diameter) were secreted by cells in both culture systems. Particle secretion was greater in epiphyseal cultures than in articular cultures with the rate decreasing as confluency was approached. These particles stained positively for lipid and alkaline phosphatase. Acridine orange was also incorporated into the granules. The 2nd cell type, a stellate-shaped cell (60 +/- 7.6 micron diameter), was found mainly surrounding the outside of colonial areas in epiphyseal cultures. These cells did not secrete small granular particles and stained positive for factor VIII. Evaluation of cultures by scanning and transmission electron microscopy further supported the presence of 2 cell types. With scanning electron microscopy, the smaller polygonal cell was characterized by varying sizes of blebs (0.03 to 0.1 micron diameter) associated with the cell membrane and small cytoplasmic processes projecting from the cell's surface.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Cartílago Articular/citología , Porcinos/anatomía & histología , Animales , Cartílago Articular/ultraestructura , Células Cultivadas , Húmero , Microscopía Electrónica , Microscopía Electrónica de Rastreo
20.
Am J Vet Res ; 50(11): 1984-7, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2619128

RESUMEN

Lectin binding of small intestinal goblet cells was examined in newborn, suckling, and weaned pigs. Sections of duodenum, proximal portion of the jejunum, distal portion of the jejunum, and ileum were embedded in a hydrophilic acrylic resin and treated with each of the following lectins: Canavalia ensiformis, Ricinus communis I, Glycine max, Ulex europaeus I, and Triticum vulgaris. Percentages of goblet cells binding each lectin were calculated within intestinal regions. Differences in lectin-binding affinity were detected among pigs of various ages and among various intestinal regions within pig age groups.


Asunto(s)
Intestino Delgado/metabolismo , Lectinas/metabolismo , Porcinos/crecimiento & desarrollo , Animales , Animales Recién Nacidos , Animales Lactantes , Duodeno/citología , Duodeno/metabolismo , Íleon/citología , Íleon/metabolismo , Intestino Delgado/citología , Yeyuno/citología , Yeyuno/metabolismo , Destete
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