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1.
Int J Biometeorol ; 65(10): 1615-1628, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33877430

RESUMEN

Climate and weather directly impact plant phenology, affecting airborne pollen. The objective of this systematic review is to examine the impacts of meteorological variables on airborne pollen concentrations and pollen season timing. Using PRISMA methodology, we reviewed literature that assessed whether there was a relationship between local temperature and precipitation and measured airborne pollen. The search strategy included terms related to pollen, trends or measurements, and season timing. For inclusion, studies must have conducted a correlation analysis of at least 5 years of airborne pollen data to local meteorological data and report quantitative results. Data from peer-reviewed articles were extracted on the correlations between seven pollen indicators (main pollen season start date, end date, peak date, and length, annual pollen integral, average daily pollen concentration, and peak pollen concentration), and two meteorological variables (temperature and precipitation). Ninety-three articles were included in the analysis out of 9,679 articles screened. Overall, warmer temperatures correlated with earlier and longer pollen seasons and higher pollen concentrations. Precipitation had varying effects on pollen concentration and pollen season timing indicators. Increased precipitation may have a short-term effect causing low pollen concentrations potentially due to "wash out" effect. Long-term effects of precipitation varied for trees and weeds and had a positive correlation with grass pollen levels. With increases in temperature due to climate change, pollen seasons for some taxa in some regions may start earlier, last longer, and be more intense, which may be associated with adverse health impacts, as pollen exposure has well-known health effects in sensitized individuals.


Asunto(s)
Polen , Tiempo (Meteorología) , Alérgenos , Cambio Climático , Humanos , Estaciones del Año , Temperatura
2.
Ann Oncol ; 28(12): 2985-2993, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28950307

RESUMEN

BACKGROUND: We sought to evaluate the impact of adjuvant chemotherapy on overall survival (OS) in patients with stage I endometrioid epithelial ovarian cancer (EEOC) or ovarian clear cell cancer (OCCC) using a national database. PATIENTS AND METHODS: The Surveillance, Epidemiology, and End Results database was used to identify patients diagnosed with International Federation of Gynecology and Obstetrics (FIGO) stage I EEOC or OCCC from 2000 to 2013. We sought to identify predictors of chemotherapy use and to assess the impact of chemotherapy on OS in these patients. OS was compared using the log-rank test and the Cox proportional hazards model. RESULTS: In all, 3552 patients with FIGO stage I EEOC and 1995 patients with stage I OCCC were identified. Of the 1600 patients (45%) with EEOC who underwent adjuvant chemotherapy, the 5-year OS rate was 90%, compared with 89% for those who did not undergo adjuvant chemotherapy (P = 0.807). Of the 1374 (69%) patients with OCCC who underwent adjuvant chemotherapy, the 5-year OS rate was 85%, compared with 83% (P = 0.439) for those who did not undergo adjuvant chemotherapy. Chemotherapy use was associated with younger age, higher substage, and more recent year of diagnosis for both the EEOC and OCCC groups. Only in the subgroup of patients with FIGO substage IC, grade 3 EEOC (n = 282) was chemotherapy associated with an improved 5-year OS-81% compared with 62% (P = 0.003) in untreated patients (HR: 0.583; 95% CI: 0.359-0.949; P = 0.030). In patients with OCCC, there was no significant effect of adjuvant chemotherapy on OS in any substage. CONCLUSIONS: Adjuvant chemotherapy was associated with improved OS only in patients with substage IC, grade 3 EEOC. In stage I OCCC, adjuvant chemotherapy was not associated with improved OS.


Asunto(s)
Adenocarcinoma de Células Claras/tratamiento farmacológico , Carcinoma Endometrioide/tratamiento farmacológico , Neoplasias Glandulares y Epiteliales/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , Adenocarcinoma de Células Claras/mortalidad , Adenocarcinoma de Células Claras/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Endometrioide/mortalidad , Carcinoma Endometrioide/patología , Carcinoma Epitelial de Ovario , Quimioterapia Adyuvante/estadística & datos numéricos , Femenino , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Glandulares y Epiteliales/mortalidad , Neoplasias Glandulares y Epiteliales/patología , Compuestos Organoplatinos/administración & dosificación , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/patología , Modelos de Riesgos Proporcionales , Programa de VERF , Tasa de Supervivencia , Estados Unidos/epidemiología , Adulto Joven
3.
Gynecol Oncol ; 129(1): 38-41, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23321065

RESUMEN

OBJECTIVE: To determine whether the frequency of cases diagnosed with stage IIIC endometrial cancer is affected by the incorporation of a modified surgical lymph node assessment. METHODS: Since 2008, we have increasingly utilized a modified nodal assessment using an algorithm that incorporates SLN mapping. For this analysis, we identified all cases of newly diagnosed endometrial cancers undergoing a minimally invasive staging procedure not requiring conversion to laparotomy from 1/1/08 to 12/31/10. Procedures were categorized as standard, modified, and hysterectomy only. Differences were based on time period: 2008 (Y1), 2009 (Y2), and 2010 (Y3). Appropriate statistical tests were used. RESULTS: We identified a total of 507 cases. The distribution of cases was 143 (Y1), 190 (Y2), and 174 (Y3). Tumor grade (P=0.05) and high-risk histologies (P=0.8) did not differ during the 3 time periods. A standard staging procedure was performed in the following cases: Y1 (93/143; 65%), Y2 (66/166; 35%), and Y3 (40/164; 23%) (P<0.001). Median operative times were as follows: Y1 (218 min), Y2 (198 min), and Y3 (176.5 min) (P<0.001). The median numbers of total lymph nodes removed among cases with at least 1 node retrieved were: Y1 (20); Y2 (10); Y3 (7) (P<0.001). Cases diagnosed as stage IIIC were as follows: Y1 (10/143; 7%), Y2 (15/166; 7.9%), and Y3 (13/164; 7.5%) (P=1.0). CONCLUSIONS: The incorporation of a modified staging approach utilizing the SLN mapping algorithm reduces the need for standard lymphadenectomy and does not appear to adversely affect the rate of stage IIIC detection.


Asunto(s)
Algoritmos , Neoplasias Endometriales/patología , Biopsia del Ganglio Linfático Centinela/métodos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Endometriales/diagnóstico , Neoplasias Endometriales/cirugía , Femenino , Humanos , Escisión del Ganglio Linfático , Metástasis Linfática , Persona de Mediana Edad , Estadificación de Neoplasias
4.
J Chromatogr A ; 1671: 462992, 2022 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-35395451

RESUMEN

We present herein new analytical protocols for the separation and structural elucidation of polyphenyls. Three commercially available chromatographic stationary phases are compared in the separation of these non-polar, unfunctionalized, positional isomers. Baseline separation of nine terphenyl and quaterphenyl isomers is achieved in under ten minutes using a rapid gradient elution HPLC method. Complete separation of these, and a further five polyphenyls, is demonstrated. We finally present a linear correlation between solvent accessible surface area and the retention times of these closely related compounds.


Asunto(s)
Cromatografía Líquida de Alta Presión , Cromatografía Líquida de Alta Presión/métodos , Solventes/química
5.
Eur Radiol ; 19(5): 1289-95, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19153744

RESUMEN

The aim of this study was to assess the ability of dual-energy computed tomography (DECT) to classify phantom renal lesions as cysts or enhancing masses. Six cylinders ranging in diameter from 0.5 to 3.0 cm were filled with distilled water or titrated iodinated contrast solutions with CT attenuation values at 120 kVp of 0 Hounsfield units (HU) for a cyst proxy or 10, 20, or 40 HU to represent enhancing masses. These were placed in a 12-cm-diameter renal phantom containing puréed beef mixed with iodinated contrast medium to simulate enhancing renal parenchyma of 100 and 250 HU and submerged within a 28-cm water bath. These combinations produced 48 individual phantom renal lesions of differing sizes, internal and parenchymal enhancement (12 cysts and 36 enhancing masses). DECT using 80 and 140 kVp was performed on a dual-source CT scanner. Commercial software created a color-encoded overlay indicating the location of iodine within the phantom. The lesions were individually graded as a cyst or enhancing mass by blinded, consensus interpretation of two genitourinary radiologists. Thirty-five of 36 enhancing masses and 10/12 cysts were correctly identified, equating to a sensitivity and specificity of 97% (95% CI 84-100%) and 83% (95% CI 51-97%), respectively. All lesions of 20- and 40-HU enhancement and 92% of 10-HU lesions were identified correctly. In a phantom model, the DECT iodine overlay technique is highly sensitive in detecting enhancing renal masses. Refinement of the technique remains necessary to improve specificity. If validated in patients, this may obviate the need for unenhanced acquisitions for renal mass characterization.


Asunto(s)
Yodo , Riñón/patología , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Tomografía Computarizada por Rayos X/métodos , Simulación por Computador , Medios de Contraste/farmacología , Humanos , Procesamiento de Imagen Asistido por Computador , Variaciones Dependientes del Observador , Fantasmas de Imagen , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Imagen Radiográfica por Emisión de Doble Fotón/instrumentación , Sensibilidad y Especificidad , Programas Informáticos , Tomografía Computarizada por Rayos X/instrumentación
6.
J Fish Biol ; 75(1): 130-41, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20738487

RESUMEN

The effects of the duration of the light phase photoperiod (8 h light or 16 h light) on the growth and hepatic insulin-like growth factor-I (IGF-I) gene expression in Nile tilapia Oreochromis niloticus were evaluated. There was a slight but not significant tendency for fish in the long light phase group (L(P)) to display elevated specific growth rate (G) both in mass (M) and standard length (L(S)) compared with that in the short light phase group (S(P);P = 0.057 for G(M);P = 0.055 for G(L)). Significantly, higher food conversion efficiency was observed in the L(P) than in the S(P). There were significant positive correlations between IGF-I concentrations and G, both in M and L(S). A significantly negative correlation was observed between IGF-I mRNA level and eye colour pattern. The lack of significant differences in G and hepatic IGF-I gene expression, despite the significant difference in feed conversion efficiency, may be related partly to the development of different levels of social interactions in the different groups within a photoperiod regime leading to increased variation of results within each group. These findings suggest that hepatic IGF-I gene expression has potential utility as a growth rate indicator for this species of fish and social status, as quantified by eye colour pattern, appears to be a much stronger determinant of growth rate and IGF-I transcript level than does light phase photoperiod length.


Asunto(s)
Cíclidos/crecimiento & desarrollo , Cíclidos/metabolismo , Regulación de la Expresión Génica/fisiología , Fotoperiodo , Somatomedinas/metabolismo , Animales , Cíclidos/genética , Color del Ojo/fisiología , Hígado/metabolismo , Distribución Aleatoria , Somatomedinas/genética
7.
Int J Gynecol Cancer ; 18(2): 269-73, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18334008

RESUMEN

The seminal Gynecologic Oncology Group study on surgical pathologic spread patterns of endometrial cancer demonstrated the risk of pelvic lymph node metastasis for clinical stage I endometrial cancer based on tumor grade and thirds of myometrial invasion. However, the FIGO staging system assigns surgical stage by categorizing depth of myometrial invasion in halves. The objective of this study was to determine the incidence of pelvic lymph node metastasis in endometrial cancer based on tumor grade and myometrial invasion as per the current FIGO staging system. We reviewed the records of all patients who underwent primary surgical staging for clinical stage I endometrial cancer at our institution between May 1993 and November 2005. To make the study cohort as homogeneous as possible, we included only cases of endometrioid histology. We also included only patients who had adequate staging, which was defined as a total hysterectomy with removal of at least eight pelvic lymph nodes. During the study period, 1036 patients underwent primary surgery for endometrial cancer. The study cohort was composed of the 349 patients who met study inclusion criteria. Distribution of tumor grade was as follows: grade 1, 80 (23%); grade 2, 182 (52%); and grade 3, 87 (25%). Overall, 30 patients (9%) had pelvic lymph node metastasis. The incidence of pelvic lymph node metastasis in relation to tumor grade and depth of myometrial invasion (none, inner half, and outer half) was as follows: grade 1-0%, 0%, and 0%, respectively; grade 2-4%, 10%, and 17%, respectively; and grade 3-0%, 7%, and 28%, respectively. We determined the incidence of pelvic nodal metastasis in a large cohort of endometrial cancer patients of uniform histologic subtype in relation to tumor grade and a one-half myometrial invasion cutoff. These data are more applicable to current surgical practice than the previously described one-third myometrial invasion cutoff results.


Asunto(s)
Carcinoma Endometrioide/patología , Neoplasias Endometriales/patología , Ganglios Linfáticos/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Metástasis Linfática , Persona de Mediana Edad , Estadificación de Neoplasias , Pelvis
8.
J Am Coll Cardiol ; 21(1): 6-14, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8417077

RESUMEN

OBJECTIVES: The purpose of this study was to determine whether variables shown to correlate with restenosis in one group (learning group) could be shown to predict recurrent stenosis in a second group (validation group). BACKGROUND: Restenosis remains a critical limitation after percutaneous transluminal coronary angioplasty. Although several clinical variables have been shown to correlate with restenosis, there are few data concerning attempts to predict recurrent stenosis. METHODS: The source of data was the clinical data base at Emory University. Patients who had had previous coronary surgery and patients who underwent coronary angioplasty in the setting of acute myocardial infarction were excluded. A total of 4,006 patients with angiographic restudy after successful angioplasty were identified. They were classified into a learning group of 2,500 patients and a validation group of 1,506 patients. The correlates of restenosis in the learning group were determined by stepwise logistic regression, and a model was developed to predict the probability of restenosis and was tested in the validation group. By using various cut points for the predicted probability of restenosis, a receiver operating characteristic curve was created. Goodness of fit of the model was evaluated by comparing average predicted probabilities with average observed probabilities within subgroups on the basis of risk level determined by linear regression analysis. RESULTS: In the learning group 1,145 patients had restenosis and 1,355 did not. Correlates of restenosis were severe angina, severe diameter stenosis before angioplasty, left anterior descending coronary artery dilation, diabetes, greater diameter stenosis after angioplasty, hypertension, absence of an intimal tear, eccentric morphology and older patient age. The model derived from the learning group was used to predict restenosis in the validation group. By varying the cut point for the predicted probability of restenosis above which restenosis is diagnosed and below which it is not, a receiver operating characteristic curve was created. The curve was close to the line of identity, reflecting a poor predictive ability. However, the model was shown to fit well with the predicted probability of restenosis correlating well with the observed probability (r = 0.98, p = 0.0001). CONCLUSIONS: Clinical variables provide limited ability to predict definitively whether a particular patient will have restenosis. However, the current model may be used to predict the probability of restenosis, with some uncertainty, at least in well characterized patients who have already had angioplasty.


Asunto(s)
Angioplastia Coronaria con Balón , Enfermedad Coronaria/epidemiología , Angioplastia Coronaria con Balón/estadística & datos numéricos , Distribución de Chi-Cuadrado , Angiografía Coronaria , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/terapia , Femenino , Georgia/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Curva ROC , Recurrencia , Análisis de Regresión , Factores de Riesgo
9.
J Am Coll Cardiol ; 37(5): 1329-34, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11300443

RESUMEN

OBJECTIVES: We sought to investigate the in vivo mechanical properties of a new self-expanding coronary stent (RADIUS) and, particularly, the subsequent vessel response over time. BACKGROUND: Preclinical studies have suggested that self-expanding stents may produce less vessel wall injury at initial deployment, leading to larger follow-up lumens than with balloon-expandable stents. However, the influence of the chronic stimulus from self-expanding stents on the vessel wall remains unknown. METHODS: Sixty-two patients were randomly assigned to either the RADIUS self-expanding stent group (n = 32) or the Palmaz-Schatz balloon-expandable stent group (n = 30). Intravascular ultrasound was performed after stent deployment and at six-month follow-up. RESULTS: At follow-up, the RADIUS stents had increased 23.6% in overall volume, while the Palmaz-Schatz stents had remained unchanged. Due to the greater mean neointimal area (3.0 +/- 1.7 mm2 vs. 1.9 +/- 1.2 mm2, p = 0.02) in the RADIUS group, no significant difference in net late lumen loss was observed between the two groups. On the other hand, analysis at the peristent margins demonstrated that mean late loss was significantly smaller in the RADIUS group than it was in the Palmaz-Schatz group (0.1 +/- 2.1 mm2 vs. 1.9 +/- 2.4 mm2, p = 0.02). CONCLUSIONS: Serial volumetric IVUS revealed that the RADIUS stents continued to enlarge during the follow-up period. In this stent implantation protocol, this expansion was accompanied by a greater amount of neointima than the Palmaz-Schatz stents, resulting in similar late lumen loss in both configurations. In the peristent margins, however, late lumen loss was minimized with the RADIUS stents.


Asunto(s)
Angioplastia Coronaria con Balón/instrumentación , Cateterismo/instrumentación , Enfermedad Coronaria/terapia , Stents , Túnica Íntima/lesiones , Ultrasonografía Intervencional , Adulto , Anciano , Enfermedad Coronaria/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Túnica Íntima/diagnóstico por imagen
10.
J Natl Cancer Inst Monogr ; (21): 7-11, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-9023823

RESUMEN

Although the mortality rate for cervical cancer in the United States has declined steadily since the introduction of the Pap smear for screening in 1945, recent statistics show a rising incidence, with the number of new cases expected in 1996 representing a record high since the mid-1980s. Part of the rising incidence may be because of increasing numbers of women in the United States who did not receive screening or having inadequate screening with the Pap smear. This paper will examine the recent patterns of cervical cancer screening in the United States, with particular attention to defining which populations are not being screened. Barriers to screening in these populations will be defined and grouped into four categories: lack of knowledge, economic, cultural, and belief system; and logistical. Successful approaches that have been used to overcome these barriers in screening programs targeted at the "hard to reach" population will be described.


Asunto(s)
Área sin Atención Médica , Neoplasias del Cuello Uterino/prevención & control , Adolescente , Adulto , Anciano , Femenino , Accesibilidad a los Servicios de Salud , Humanos , Tamizaje Masivo , Persona de Mediana Edad , Estados Unidos
11.
Gene ; 242(1-2): 295-305, 2000 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-10721723

RESUMEN

We cloned and characterized the woodchuck tumor necrosis factor (TNF) and lymphotoxin-alpha, -beta (LT-alpha, -beta) cDNAs, genes and proteins to facilitate study of the functions of these cytokines during the course of woodchuck hepatitis virus (WHV) infection. Woodchuck cDNA and genomic DNA libraries were screened with woodchuck-specific DNA probes to isolate the cDNA and gene clones for TNF, LT-alpha and LT-beta. The cDNAs for woodchuck TNF, LT-alpha and LT-beta code for proteins of 233, 205 and 310 amino acids respectively. The polypeptide encoded by each gene among woodchucks, humans and mice can differ: the human TNF, LT-alpha and LT-beta genes encode polypeptides of 233, 205 and 244 amino acids respectively, whereas the mouse TNF, LT-alpha and LT-beta genes encode polypeptides of 235, 202 and 306 amino acids respectively. In the woodchuck, there are four exons for TNF, four exons for LT-alpha and three exons for LT-beta. The RNA splicing patterns for TNF, LT-alpha and LT-beta genes are identical among woodchucks, humans and mice, except that the human LT-beta gene contains four exons. The woodchuck TNF gene promoter contains consensus sequences for binding of AP-1, AP-2, C/EBPbeta, CRE, Egr-1, Ets, NF-AT, NF-kappaB and SP-1 transcription factors. LT-alpha has AP-2, Ets, NF-kappaB, SP-1 and STAT binding sites, and LT-beta has Egr-1/SP-1, Ets and NF-kappaB binding sites. The bacterially expressed woodchuck TNF and LT-alpha proteins exhibited cytotoxic activities on both mouse L929B and woodchuck A2 cells in the presence of actinomycin D. The specific activities of TNF and LT-alpha were 2.62x10(8) units/mg and 2.22x10(3) units/mg respectively for L929B cells, and 1.05x10(9) units/mg and 3.56x10(4) units/mg respectively for A2 cells. However, only woodchuck TNF showed cytotoxic activity on human HepG2 cells, with a specific activity of 6.55x10(7) units/mg in the presence of actinomycin D. The data obtained from this study will be useful to future investigations of the TNF and LT antitumor and anti-viral activities, and their therapeutic potential in the woodchuck model for human hepatitis B virus (HBV).


Asunto(s)
Linfotoxina-alfa/genética , Marmota/genética , Proteínas de la Membrana/genética , Factor de Necrosis Tumoral alfa/genética , Animales , Secuencia de Bases , Sitios de Unión , Línea Celular , ADN/química , ADN/genética , ADN/metabolismo , ADN Complementario/química , ADN Complementario/genética , ADN Complementario/aislamiento & purificación , Exones , Expresión Génica , Genes/genética , Glutatión Transferasa/genética , Glutatión Transferasa/metabolismo , Humanos , Intrones , Linfotoxina-alfa/metabolismo , Linfotoxina-alfa/farmacología , Linfotoxina beta , Proteínas de la Membrana/metabolismo , Datos de Secuencia Molecular , Polimorfismo Genético , Regiones Promotoras Genéticas , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Recombinantes de Fusión/farmacología , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico , Factores de Transcripción/metabolismo , Células Tumorales Cultivadas/citología , Células Tumorales Cultivadas/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismo , Factor de Necrosis Tumoral alfa/farmacología
12.
Eur J Cancer ; 30A(10): 1414-9, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7833094

RESUMEN

The aim of the scheme was to determine consistency of histopathological reporting in the United Kingdom National Breast Screening Programme. This external quality assessment scheme involved 51 sets of 12 slides which were circulated to 186-251 pathologists at intervals of 6 months for 3 years. Participants recorded their diagnoses on standard reporting forms, which were submitted to the U.K. National Cancer Screening Evaluation Unit for analysis. A high level of consistency was achieved in diagnosing major categories of breast disease including invasive carcinoma and the important borderline lesions, radial scar and ductal carcinoma in situ (DCIS), the latter exceeding a national target set prior to the onset of the scheme. Atypical hyperplasia (AH) was reported with much less consistency although, where it was the majority opinion, over 86% of diagnoses were of benign disorders and only 14% were of DCIS. Inconsistency was encountered in subtyping and measuring DCIS, the former apparently due to current uncertainties about classification and the latter to poor circumscription, variation in size in different sections and merging with zones of AH. Reporting prognostic features of invasive carcinomas was variable. Measurement of size was achieved with adequate consistency except in a small number of very poorly circumscribed tumours. Grading and subtyping were inconsistent although the latter was not specifically tested and will be the subject of future study. Members of the National Coordinating Group achieved greater uniformity than the remainder of the participants in all diagnostic categories, but both groups experienced similar types of problem. Our findings suggest that participation in the scheme improves diagnostic consistency. In conclusion, consistency in diagnosing invasive carcinoma and radial scar is excellent, and good in DCIS, but improvements are desirable in diagnosing atypical hyperplasia, classifying DCIS and reporting certain prognostic features of invasive tumours. Such improvements will require further research, the development of improved diagnostic criteria and the dissemination of clearer guidelines.


Asunto(s)
Neoplasias de la Mama/patología , Mama/patología , Tamizaje Masivo , Garantía de la Calidad de Atención de Salud , Enfermedades de la Mama/patología , Neoplasias de la Mama/prevención & control , Carcinoma in Situ/patología , Carcinoma Ductal de Mama/patología , Diagnóstico Diferencial , Femenino , Humanos , Hiperplasia/patología , Invasividad Neoplásica , Variaciones Dependientes del Observador , Lesiones Precancerosas/patología , Reino Unido
13.
Eur J Cancer ; 26(7): 777-9, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2145893

RESUMEN

The c-erbB-1 and c-erbB-2 proto-oncogenes are frequently activated by gene amplification and overexpression in a variety of human cancers. In an analysis of a large series of benign and malignant thyroid tumours, no abnormalities of structure or expression of either of c-erbB-1 or c-erbB-2 were found. Activation of these oncogenes is not a necessary event in neoplasia of this epithelial system.


Asunto(s)
Proto-Oncogenes , Neoplasias de la Tiroides/genética , ADN de Neoplasias/análisis , Amplificación de Genes , Expresión Génica , Reordenamiento Génico , Humanos , Oligonucleótidos/análisis
14.
J Med Chem ; 36(21): 3056-60, 1993 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-8230091

RESUMEN

The solution conformation of the antitumor drug streptonigrin in THF-d8 has been determined by dynamic 1H NMR spectroscopy (400 MHz). The major solution conformation agrees with the structure observed in the solid state [Chiu, Y.-Y.; Lipscomb, W. N. J. Am. Chem. Soc. 1975, 97, 2525-30]. Rings A, B, and C are coplanar, with ring C held in place by a hydrogen bond from the amino group on ring C and the pyridyl nitrogen in ring B. This conformation is stable in the range pH 3.9-8.9. At lower pH, the hydrogen bond is disrupted due to protonation of the pyridyl nitrogen in ring B. The major species present at pH 3.9-8.9 and 180 K is the zwitterion 1b (80%). Below 190 K, slow proton transfer between the free acid 1a and the zwitterion 1b is observed on the NMR time scale. Addition of a catalytic amount of base to the solution increases the rate of exchange 1a<-->1b, and only one set of resonances is observed. In CD2Cl2 this proton transfer is not observed. Implications for the structure(s) of metal complexes formed by streptonigrin are discussed.


Asunto(s)
Estreptonigrina/química , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Conformación Molecular , Soluciones , Temperatura
15.
Proc Biol Sci ; 271(1547): 1507-11, 2004 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-15306323

RESUMEN

Cold-hardy insects overwinter by one of two main strategies: freeze tolerance and freeze avoidance by supercooling. As a general model, many freeze-tolerant species overwinter in extreme climates, freeze above -10 degrees C via induction by ice-nucleating agents, and once frozen, can survive at temperatures of up to 40 degrees C or more below the initial freezing temperature or supercooling point (SCP). It has been assumed that the SCP of freeze-tolerant insects is unaffected by the freezing process and that the freeze-tolerant state is therefore retained in winter though successive freeze-thaw cycles of the body tissues and fluids. Studies on the freeze-tolerant larva of the hoverfly Syrphus ribesii reveal this assumption to be untrue. When a sample with a mean 'first freeze' SCP of -7.6 degrees C (range of -5 degrees C to -9.5 degrees C) were cooled, either to -10 degrees C or to their individual SCP, on five occasions, the mean SCP was significantly depressed, with some larvae subsequently freezing as low as -28 degrees C. Only larvae that froze at the same consistently high temperature above -10 degrees C were alive after being frozen five times. The wider occurrence of this phenomenon would require a fundamental reassessment of the dynamics and distinctions of the freeze-tolerant and freeze-avoiding strategies of insect overwintering.


Asunto(s)
Aclimatación/fisiología , Dípteros/fisiología , Análisis de Varianza , Animales , Dípteros/crecimiento & desarrollo , Inglaterra , Congelación , Larva/crecimiento & desarrollo , Larva/fisiología , Estaciones del Año , Temperatura
16.
Am J Cardiol ; 70(3): 293-9, 1992 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-1632391

RESUMEN

Restenosis remains a critical limitation of percutaneous transluminal coronary angioplasty (PTCA). Recent experimental and clinical data have suggested that lovastatin, an hydroxymethylglutaryl coenzyme A reductase inhibitor, may reduce the rate of restenosis through reduction of low density-lipoprotein (LDL) cholesterol or possibly by direct effects. Lovastatin may therefore produce favorable alterations in endothelial healing, resulting in a decreased smooth muscle cell proliferative response to injury after angioplasty. Emory University, in conjunction with Merck Research Laboratories, has initiated a 10-center double-blinded, placebo-controlled, randomized trial to assess the effect of both pretreatment and aggressive lipid lowering with lovastatin in reducing the rate of restenosis. Lovastatin achieves approximately 75% of its effect on LDL cholesterol by 1 week. Thus, patients scheduled for PTCA are randomly assigned pretreatment with lovastatin, 40 mg twice daily, or placebo 7 to 10 days before PTCA. Therapy is continued for 6 months, at which time repeat coronary arteriography is performed. A detailed safety algorithm was designed, with patients receiving lovastatin and matching placebo back-titrated on a 1:1 basis for LDL cholesterol less than 50 mg/dl. The power is a 90%, alpha = 0.05, 2-tailed test to reduce restenosis from 30 to 15%. The sample size is 360 patients in the 2 arms; allowing for a 10% dropout rate, approximately 400 patients will be randomized. Patients with successful PTCA, less than 50% residual diameter stenosis and greater than or equal to 20% diameter stenosis reduction are analyzed for restenosis at 4 to 6 months by quantitative coronary arteriography.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Angioplastia Coronaria con Balón , Enfermedad Coronaria/terapia , Lovastatina/administración & dosificación , Angiografía Coronaria , Enfermedad Coronaria/diagnóstico , Enfermedad Coronaria/prevención & control , Método Doble Ciego , Electrocardiografía , Prueba de Esfuerzo , Humanos , Recurrencia
17.
Am J Cardiol ; 72(15): 1107-13, 1993 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-8237797

RESUMEN

The purpose of this study was to determine whether in patients with 2 sites dilated by percutaneous transluminal coronary angioplasty (PTCA), the sites undergo restenosis independently. Although restenosis remains a critical limitation after PTCA, there is little information separating site- and patient-dependent determinants of restenosis. In particular, if patients with 2 sites dilated have restenosis at 0 or 2 sites more frequently and at 1 site less frequently than expected by random chance, then patient-related factors may be important in the restenosis process. The source of data was the clinical data base at Emory University. Patients who had previously coronary surgery or PTCA, and those who underwent PTCA in the setting of acute myocardial infarction were excluded. In all, 515 patients with 2 sites dilated undergoing angiographic restudy at 4 months to 1 year after PTCA formed the study population. Site 1 was the first site dilated. At site 1, 224 of 515 sites (45%) were restenotic, and at site 2, 193 (33%) were restenotic. Multiple clinical and angiographic variables were analyzed as possible correlates of restenosis. The most powerful univariate and multivariate correlate of restenosis at either site 1 or 2 was the behavior of the other site. If site 2 was patent, then site 1 was restenotic 28% of the time compared with 69% if site 2 was restenotic. If site 1 was patent, site 2 was restenotic 20% of the time compared with 60% if site 1 was restenotic. This relation was stronger if the 2 sites were in the same coronary artery.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Angioplastia Coronaria con Balón , Enfermedad Coronaria/patología , Enfermedad Coronaria/terapia , Anciano , Constricción Patológica/patología , Constricción Patológica/terapia , Enfermedad Coronaria/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Probabilidad , Radiografía , Recurrencia
18.
Br J Pharmacol ; 73(2): 517-23, 1981 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6165421

RESUMEN

1 The effects of substance P and related peptides on amylase release from rat parotid gland slices have been investigated. 2 Supramaximal concentrations (1 microM) of substance P caused enhancement of amylase release over the basal level within 1 min; this lasted for at least 40 min at 30 degrees C. 3 Substance P-stimulated amylase release was partially dependent on extracellular calcium and could be inhibited by 50% upon removal of extracellular calcium. 4 Substance P stimulated amylase release in a dose-dependent manner with an ED50 of 18 nM. 5 All C-terminal fragments of substance P were less potent than substance P in stimulating amylase release. The C-terminal hexapeptide of substance P was the minimum structure for potent activity in this system, having 1/3 to 1/8 the potency of substance P. There was a dramatic drop in potency for the C-terminal pentapeptide of substance P or substance P free acid. Physalaemin was more potent than substance P (ED50 = 7 nM), eledoisin was about equipotent with substance P (ED50 = 17 nM), and kassinin less potent that substance P (ED50 = 150 nM). 6 The structure-activity profile observed is very similar to that for stimulation of salivation in vivo, indicating that the same receptors are involved in mediating these responses. 7 All the fragments of substance P tested were capable of eliciting a full amylase release response. This indicates that the apparent partial agonist action of the C-terminal nonapeptide fragment on in vivo salivation is not explicable at the receptor level.


Asunto(s)
Amilasas/metabolismo , Glándula Parótida/enzimología , Péptidos/farmacología , Sustancia P/farmacología , alfa-Amilasas/metabolismo , Animales , Calcio/fisiología , Técnicas In Vitro , Masculino , Glándula Parótida/efectos de los fármacos , Ratas , Receptores Adrenérgicos alfa/efectos de los fármacos , Receptores Muscarínicos/efectos de los fármacos , Salivación/efectos de los fármacos , Tetracaína/farmacología
19.
Mol Cell Endocrinol ; 157(1-2): 67-73, 1999 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-10619398

RESUMEN

cDNA encoding putative transthyretin (prealbumin, TTR) was cloned from liver of the marine fish Sparus aurata. The cDNA contains an open reading frame of 453 nt, encoding for a TTR precursor of 151 amino acids. The deduced amino acid sequence of S. aurata TTR shows identity of 54, 57.3 and 54.1% with lizard, chicken and rat TTR, respectively. Northern blot analysis revealed a TTR transcript of about 700 nt, highly expressed in liver, but also in skin. Low expression was detected in 12 other tissues by using RT-PCR. The ontogeny of TTR expression during early stages of larval development of S. aurata was examined by Northern blot analysis using poly(A+)RNA from larvae collected on different days after hatching. TTR mRNA was seen already on the first day after hatching and its steady-state levels increased from Day 15 onwards. Molecular cloning of a TTR-like cDNA from fish suggests that TTR evolved earlier in vertebrate development than previously thought. Furthermore, its expression in liver exceeds by several-fold that found in brain, yet high expression is also found in skin. These results suggest that in fish, liver is the main site of TTR synthesis, but that TTR may have an important function in fish skin.


Asunto(s)
Perciformes/crecimiento & desarrollo , Perciformes/genética , Prealbúmina/genética , Factores de Edad , Animales , Northern Blotting , Clonación de Organismos , ADN Complementario/química , ADN Complementario/aislamiento & purificación , Regulación del Desarrollo de la Expresión Génica , Larva/genética , Hígado/química , Hígado/crecimiento & desarrollo , Sondas Moleculares , Datos de Secuencia Molecular , Perciformes/metabolismo , Prealbúmina/biosíntesis , ARN Mensajero/biosíntesis , Alineación de Secuencia , Piel/química , Distribución Tisular/genética
20.
J Clin Pathol ; 19(2): 103-13, 1966 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-5909693

RESUMEN

The pathological features of 67 cases of medullary carcinoma of the thyroid were studied, and when possible the case histories were reviewed. The typical tumour is sharply demarcated but not encapsulated, is composed of sheets of cells having eosinophilic granular cytoplasm, with the deposition of amyloid in the stroma. We would stress the frequency of binucleate cells, the scarcity of mitoses, and the frequent occurrence of calcification. The clinical findings show a wide variation in age at presentation of this tumour, and a wide variation in prognosis, with a mean survival from the time of presentation to hospital of 6.6 years, the longest being 21 years. Two of this group of patients also had phaeochromocytomas; these two and three others showed small papillary tumours of the eyelids, lips, and tongue. Despite the variation in some of its characteristics, medullary carcinoma of the thyroid is considered to be a distinct and sharply defined entity. It appears to be the only type of thyroid carcinoma associated with phaeochromocytoma, the only type associated with multiple mucosal neuromas and the only type with a familial incidence. These findings emphasize the validity of its separation from other types of thyroid carcinoma.


Asunto(s)
Neoplasias de la Tiroides/patología , Adolescente , Adulto , Anciano , Amiloide , Carcinoma/patología , Niño , Preescolar , Femenino , Humanos , Técnicas In Vitro , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Mortalidad , Metástasis de la Neoplasia
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