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1.
Acad Radiol ; 6(6): 333-8, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10376063

RESUMEN

RATIONALE AND OBJECTIVES: The purpose of this study was to determine the accuracy of touch-preparation cytologic examination of breast core biopsy specimens in predicting benign or malignant core histologic results. MATERIALS AND METHODS: One hundred two core biopsies were performed on 88 women with stereotactic or ultrasonographic (US) guidance. Slides were prepared by smearing one core sample on each slide, spraying the slides with fixative, and staining them with the Papanicolaou technique. Slides were blindly reviewed by a cytopathologist. Cytologic results were categorized as positive for malignancy, not diagnostic for malignancy, or insufficient for diagnosis. Results were correlated with histologic results from all specimens obtained during the core biopsy. RESULTS: Imaging depicted the lesions sampled for biopsy as masses (n = 70), clustered calcifications (n = 29), focal asymmetries (n = 2), or architectural distortion (n = 1). Touch-preparation slides of 87 (85%) lesions contained sufficient material for diagnosis. Cytologic results correctly identified 12 of 16 (three of five intraductal and nine of 11 invasive) malignancies in 10 of 13 masses and two of three clusters of calcifications. Two false-positive results occurred, both with fibroadenomas. Overall, touch-preparation studies produced 69 true-negative and four false-negative results. Excluding slides with insufficient material, the sensitivity, specificity, and accuracy of touch-preparation results were 75%, 97%, and 93%, respectively. Including insufficient samples, accuracy was 79%. CONCLUSION: Although touch-preparation cytologic examination of breast core biopsy specimens is fairly accurate in prediction of benign or malignant core histologic results, its correlation with histologic results is not sufficient to justify routine use in immediate counseling and treatment planning.


Asunto(s)
Biopsia con Aguja/métodos , Neoplasias de la Mama/patología , Mama/patología , Adulto , Anciano , Anciano de 80 o más Años , Calcinosis/diagnóstico , Citodiagnóstico , Reacciones Falso Negativas , Reacciones Falso Positivas , Femenino , Técnicas Histológicas , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad
5.
J Prosthet Dent ; 48(4): 429-31, 1982 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6957597

RESUMEN

Nine hundred specimens of six shades of two commercially available dental porcelains were made with different thicknesses of opaque and body porcelain. The color of specimens were compared with shade guide samples by seven observers. The results were as follows: 1. The thickness of opaque and body porcelain to produce optimum color varies from shade and in different porcelain systems. 2. Complete visual mask out of the alloy by the opaque may not produce the desired shade. 3. Excessive opaque will not effect the shade of porcelain noticeably, whereas excessive body porcelain influences the shade of porcelain. 4. Manufacturers' recommendations for each shade should include the optimum required thickness of both opaque and body porcelain.


Asunto(s)
Color , Porcelana Dental , Revestimiento para Colado Dental , Aleaciones de Oro , Fosfatos , Propiedades de Superficie
6.
Toxicol Appl Pharmacol ; 96(1): 159-67, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3188021

RESUMEN

Mature, untreated rainbow trout display a marked sex difference in the level and activity of the P-450-dependent mixed-function oxidase system with males demonstrating higher levels than females. This difference is accentuated in the trunk kidney, is specific for endogenous substrates such as lauric acid and sex steroids, and is correlated with greater levels of the constitutive cytochrome P-450 isozyme, LM2. Using an immunohistochemical technique, the cellular localization of P-450 LM2 and P-450 LM4b, the major beta-naphthoflavone inducible isozyme, in the head and trunk kidney of male, female, and juvenile trout has been demonstrated. Immunostaining for P-450 LM2 was observed in the cytoplasm of cells in the second portion (P2) of the proximal tubules of both male and female trout. In male fish, staining appeared to be more intense and involved most of the P2 segments in a tissue section. In female fish, P2 staining was moderate and involved fewer segments. Low staining intensity for P-450 LM4b was observed in the cytoplasm of cells both in the first portion of the proximal tubules and in P2 of male and female fish. Sexual dimorphism was not apparent. The finding of greater amounts of P-450 LM2 in males and low levels of P-450 LM4b in untreated male and female trout confirms previous biochemical studies. Localization of P-450 isozymes in the proximal tubules is consistent with findings in mammalian species. Moderate immunostaining by anti-P-450 LM4b IgG also was observed in the interrenal cells of the head kidney of male, female, and juvenile trout.


Asunto(s)
Sistema Enzimático del Citocromo P-450/metabolismo , Riñón/enzimología , Salmonidae/metabolismo , Trucha/metabolismo , Animales , Valores de Referencia
7.
Rev. cient. (Guatem.) ; 5(1): 8-16, 2009. tab
Artículo en Español | LILACS | ID: lil-655697

RESUMEN

Fue evaluada la actividad de dos extractos del hongo comestible Grifola frondosa (Dicks; Fr) S.F. Gray, conocido comúnmente como maitake sobre el sistema inmune humano. Se estudió la actividad inmunomoduladora de los extractos acuoso y etanólico obtenidos del cuerpo fructífero del hongo sobre los linfocitos por medio de un ensayo linfoproliferativo y fueron realizados ensayos hematolíticos in vitro para probar su influencia sobre las vías clásicas y alterna del sistema de complemento. El ensayo de linfoproliferación fue realizado colocando linfocitos purificados expuestos a los extractos y cultivados para una evaluación final colorimétrica con XTT, una sal de tetrazolio que es reducida a un compuesto coloreado y soluble por la actividad enzimática mitocondrial presente en células vivas...


Asunto(s)
Antígenos Fúngicos , Bioensayo , Factores Inmunológicos , Grifola , Sistema Inmunológico
8.
Fundam Appl Toxicol ; 5(5): 893-901, 1985 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-4065462

RESUMEN

T-2 toxin was given as a single intravascular dose at either 0.6 or 4.8 mg/kg to different groups of 50-kg female swine. Blood samples were taken at hourly intervals for determination of concentrations or activities of the following substances in serum or plasma: creatinine, blood urea nitrogen, inorganic phosphorus, total calcium, ultrafilterable calcium, magnesium, sodium, potassium, chloride, total protein, albumin, cholesterol, glucose, alkaline phosphatase, aspartate aminotransferase, and total bilirubin. Coagulation analyses included prothrombin time, partial thromboplastin time, activated coagulation time, and fibrin degradation products. Red blood cell, white blood cell, and platelet counts, hemoglobin concentrations, and hematocrits were determined from whole blood samples. An initial leukocytosis was followed by a leukopenia. The numbers of red cells, the hemoglobin concentration, and the hematocrit were increased. Nucleated red blood cells were seen in the blood smears. The serum concentration of bound calcium decreased, while phosphorus, magnesium, and potassium increased. Clinical screening tests detected no evidence of a coagulopathy in swine given T-2 toxin intravascularly.


Asunto(s)
Coagulación Sanguínea/efectos de los fármacos , Enzimas/sangre , Sesquiterpenos/toxicidad , Toxina T-2/toxicidad , Fosfatasa Alcalina/sangre , Animales , Recuento de Células Sanguíneas , Nitrógeno de la Urea Sanguínea , Calcio/sangre , Femenino , Concentración de Iones de Hidrógeno , Metales/sangre , Fósforo/sangre , Porcinos , Factores de Tiempo
9.
Exp Mol Pathol ; 50(3): 348-61, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2656290

RESUMEN

An immunohistochemical technique was used to localize the major constitutive cytochrome P450 isozyme, P450 LM2, and the major beta-naphthoflavone-inducible isozyme, P450 LM4b, in the livers of untreated and aflatoxin B1 (AFB1)-initiated, tumor-bearing rainbow trout. In hepatic tissue sections from untreated trout, no regular anatomical pattern within the hepatic parenchymal cells could be discerned for either isozyme. Immunostaining was observed for P450 LM2 along the sinusoidal border of some of the parenchymal cells, there was moderate staining within the cytoplasm of most cells, and there were focal areas of increased staining. There was intense, uniform immunostaining for P450 LM2 within the cytoplasm of the bile duct cells, in the endothelial lining of arterioles, and along the epithelial surface of the gall bladder. Staining for P450 LM4b in livers from untreated trout was barely detectable. In liver tissue sections from AFB1-treated tumor-bearing fish, P450 LM2 appeared to be reduced and P450 LM4b was absent in the hepatocellular carcinoma nodules. An apparent increase in immunostaining for P450 LM4b was observed in nonneoplastic cells juxtaposed next to neoplastic cells as well as in areas distant to the tumors. These results may indicate that the pattern of P450 isozymes is altered in nonneoplastic cells of tumor-bearing trout livers.


Asunto(s)
Sistema Enzimático del Citocromo P-450/análisis , Isoenzimas/análisis , Neoplasias Hepáticas/enzimología , Hígado/enzimología , Animales , Técnicas para Inmunoenzimas , Inmunohistoquímica , Distribución Aleatoria , Trucha
10.
J Prosthet Dent ; 57(4): 450-4, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2883315

RESUMEN

Strength of a soldered palladium alloy, PGC (Engelhard Corp.), and a soldered medium gold alloy, PGX (Engelhard Corp.), was examined. The results obtained were as follows: Highest strength was observed with postsoldered specimens of PGC alloy. Microstructural examination of postsoldered specimens revealed nearly pore-free solder joints with PGC and PGX alloys, and fracture appeared at the solder-alloy interface with PGC and PGX alloys. Microstructural examination of presoldered and presoldered/thermocycled specimens revealed that presoldered specimens of PGC and PGX alloys exhibited intrasolder fracture; PGX solder joints had considerably less porosity, which may explain the equivalent bond strengths of all the soldered specimens and the yield point of the controls; PGC solder joints exhibited large quantities of pores, which may explain the lower strength; pores observed in PGC alloy may be the result of the high fusing temperature of the solder; and these results indicate a need to develop a new presolder for PGC. The best result was obtained with postsoldered specimens of the PGC alloy. However, for PGX alloy, either postsolder or presolder techniques can be used.


Asunto(s)
Aleaciones Dentales , Soldadura Dental , Aleaciones de Oro , Paladio , Porcelana Dental , Humanos , Microscopía Electrónica de Rastreo , Estrés Mecánico , Propiedades de Superficie
11.
J Prosthet Dent ; 64(6): 677-80, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2079673

RESUMEN

Palladium-based alloys have had a significant import on the fabrication of ceramometal restorations. This article compares the bond strengths of four palladium-based alloys with that of a high-noble alloy. Tests were designed to closely represent clinical situations. Bond strengths of the palladium alloys compared favorably with the high-noble metals; palladium alloys containing up to 2% gold were the best.


Asunto(s)
Aleaciones Dentales/química , Recubrimiento Dental Adhesivo , Porcelana Dental/química , Aleaciones de Oro/química , Paladio/química , Análisis del Estrés Dental , Elasticidad , Estrés Mecánico , Propiedades de Superficie , Resistencia a la Tracción
12.
Fundam Appl Toxicol ; 5(5): 879-92, 1985 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3840756

RESUMEN

T-2 toxin given as a single intravascular dose to swine produced a shock syndrome. Dosages of 0.6 or 4.8 mg/kg were administered to different groups of swine. Shock was characterized by reductions in cardiac output and blood pressure, and increased plasma concentrations of epinephrine, norepinephrine, thromboxane B2, 6-keto PGF1 alpha, and lactate. Total peripheral resistance was unchanged in the high-dose group but decreased in the low-dose group. Pulmonary vascular resistance increased in both groups. Decreases occurred in arterial pH and arterial oxygen partial pressure. No alterations occurred in plasma concentrations of histamine or serotonin.


Asunto(s)
Sesquiterpenos/toxicidad , Toxina T-2/toxicidad , 6-Cetoprostaglandina F1 alfa/sangre , Equilibrio Ácido-Base/efectos de los fármacos , Animales , Presión Sanguínea/efectos de los fármacos , Temperatura Corporal/efectos de los fármacos , Gasto Cardíaco/efectos de los fármacos , Catecolaminas/sangre , Femenino , Hemodinámica/efectos de los fármacos , Consumo de Oxígeno/efectos de los fármacos , Porcinos , Tromboxano B2/sangre , Factores de Tiempo , Resistencia Vascular/efectos de los fármacos
13.
Fundam Appl Toxicol ; 8(3): 298-309, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3569701

RESUMEN

The gross and microscopic changes in swine following a single intravascular (iv) dose of T-2 toxin are described and evaluated quantitatively. T-2 toxin, in 70% ethanol, was given iv at 0 (5 pigs), 0.6 (5 pigs), 1.2 (1 pig), 4.8 (5 pigs), or 5.4 (2 pigs) mg/kg to 40 to 60 kg female crossbred pigs. The 4.8 and 5.4 mg/kg group pigs died between 5 and 10.5 hr after treatment, while the 0, 0.6, and 1.2 mg/kg pigs were killed at 24, 24, and 12 hrs after treatment, respectively. Morphologic examination was performed at the gross and light microscopic levels. In addition, a quantitative evaluation of microscopic changes present in lymphoid tissues and intestinal tract was performed using a semiquantitative scoring system. Gross lesions in the T-2-treated pigs consisted of edema, congestion, and hemorrhage of the lymph nodes and pancreas; congestion and hemorrhage of the gastrointestinal mucosa, subendocardium, adrenal gland, and meninges; and edema of the gall bladder. Histologic examination confirmed the gross observations. Additional microscopic lesions included widespread degeneration and necrosis of the lymphoid tissues as well as of the surface and crypt epithelium of the gastrointestinal mucosa; mild scattered necrosis of pancreatic acinar cells, myocardium, bone marrow cells, adrenal cortical cells, and tubular epithelium of renal medulla; and mild interstitial pneumonia. A dose-dependent increase in lesion severity was observed except for the pancreatic lesion which was slightly more apparent in the pigs from the 0.6 mg/kg group. These findings indicate that T-2 toxin-induced lesions in the lymphoid tissues and gastrointestinal tract of pigs are similar to those of other species the pancreas and heart should be considered as additional target organs in the pig, and both rapidly dividing cells and those with little or no turnover are damaged by T-2 toxin.


Asunto(s)
Sesquiterpenos/toxicidad , Enfermedades de los Porcinos/inducido químicamente , Toxina T-2/toxicidad , Animales , Sistema Digestivo/efectos de los fármacos , Sistema Digestivo/patología , Femenino , Hemodinámica , Inyecciones Intravenosas , Ganglios Linfáticos/efectos de los fármacos , Ganglios Linfáticos/patología , Porcinos , Enfermedades de los Porcinos/patología , Toxina T-2/administración & dosificación , Timo/efectos de los fármacos , Timo/patología
14.
Clin Infect Dis ; 26(2): 365-72, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9580096

RESUMEN

Human abdominal angiostrongyliasis is a potentially fatal disease caused by Angiostrongylus costaricensis, a nematode found in the Americas. During the period of December 1994 through August 1995, an outbreak of this disease occurred in Guatemala. We identified 22 cases of abdominal angiostrongyliasis and conducted a matched case-control study to identify risk factors for illness. The median age of the 18 cases enrolled in the study was 37 years (range, 9-68 years), and 11 (61.1%) were male. Consumption of the following six raw food items was associated with angiostrongyliasis: mint (odds ratio [OR], 6.9; 95% confidence interval [CI], 1.5-66.0), shrimp (OR, infinite; 95% CI, 1.4 to infinite), and four kinds of ceviche that reportedly contained raw mint (OR for consumption of mint or ceviche that contained mint, 7.0; 95% CI, 1.0-315). We conclude that raw mint was the likely vehicle of infection for this outbreak. To our knowledge, this is the first reported outbreak of abdominal angiostrongyliasis and the first time that a specific food item has been epidemiologically linked to the disease.


Asunto(s)
Angiostrongylus , Brotes de Enfermedades , Infecciones por Strongylida/epidemiología , Abdomen , Adolescente , Adulto , Anciano , Animales , Estudios de Casos y Controles , Niño , Estudios de Cohortes , Ambiente , Femenino , Microbiología de Alimentos , Guatemala/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Infecciones por Strongylida/patología , Infecciones por Strongylida/fisiopatología
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