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2.
J Exp Biol ; 213(5): 759-68, 2010 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-20154191

RESUMEN

Properties of prey sensory systems are important factors shaping the design of signals generated by organisms exploiting them. In this study we assessed how prey sensory preference affected the exploiter signal design by investigating the evolutionary relationship and relative attractiveness of linear and cruciate form web decorations built by Argiope spiders. Because insects have an innate preference for bilaterally symmetrical patterns, we hypothesized that cruciate form decorations were evolved from linear form due to their higher visual attractiveness to insects. We first reconstructed a molecular phylogeny of the Asian members of the genus Argiope using mitochondrial markers to infer the evolutionary relationship of two decoration forms. Results of ancestral character state reconstruction showed that the linear form was ancestral and the cruciate form derived. To evaluate the luring effectiveness of two decoration forms, we performed field experiments in which the number and orientation of decoration bands were manipulated. Decoration bands arranged in a cruciate form were significantly more attractive to insects than those arranged in a linear form, no matter whether they were composed of silks or dummies. Moreover, dummy decoration bands arranged in a cruciate form attracted significantly more insects than those arranged in a vertical/horizontal form. Such results suggest that pollinator insects' innate preference for certain bilateral or radial symmetrical patterns might be one of the driving forces shaping the arrangement pattern of spider web decorations.


Asunto(s)
Insectos/fisiología , Seda/química , Arañas/fisiología , Visión Ocular/fisiología , Animales , Complejo IV de Transporte de Electrones/genética , Evolución Molecular , Filogenia , Conducta Predatoria , Análisis de Regresión , Arañas/genética
3.
Artículo en Zh | MEDLINE | ID: mdl-29429179

RESUMEN

Objective: To evaluate the application of the central lymph node dissection (CLND) for papillary thyroid carcinoma (PTC) in cN0 T1/T2. Methods: Retrospective analysis of 532 cases with PTC in cN0 T1/T2 who underwent CLND between October 2014 and September 2016 in the Department of Thyroid Surgery, the First Affiliated Hospital of the Kunming Medical University. The incidence of central lymph node (CLN) metastasis and risk factors were analyzed. Results: CLN metastasis rates: 41.2% (42/102) in males vs 34.9% (150/430) in females, P=0.252; 33.9% (116/342) in single focal carcinoma vs 40.4% (74/183) in multifocal carcinoma, P=0.157; 44.0% (125/284) in patients with 45 years old or less vs 27.0% (67/248) in patients more than 45 years old, P=0.000; 30.3% (113/373) in microcarcinoma vs 50.9% (81/159) in non-microcarcinoma, P=0.000.In unilateral lesions, ipsilateral CLN metastasis was correlated with the tumor diameter (P=0.012), but not with the number of lesions (P=0.653). also contralateral CLN metastasis was correlated with the tumor diameter (P=0.000), but not with the number of lesions (P=0.815). For the left or right unilateral single focal lesion, the tumor diameter was not correlated with the metastasis of the posterior to right recurrent laryngeal nerve central lymph nodes (LN-prRLN-CLN) (P=0.652, P=0.088). But in bilateral multifocal carcinoma the tumor diameter was correlated with metastasis of LN-prRLN-CLN (P=0.039). Conclusions: Prophylactic CLND is reasonable for PTC in cN0 T1/T2. A bilateral CLND should be conducted for patients with bilateral multi-focus cancer and unilateral or bilateral non-microcarcinoma, especially in patients more than 45 years old. For unilateral single focal microcarcinoma on the right, the content of CLND should be from laryngeal nerve on right center to posterior branche; for unilateral single focal microcarcinoma on the left side, the left CLND should be conducted. An ipsilateral CLND can be considered in patients with unilateral multifocal microcarcinoma, and generally a routine dissection of the LN-prRLN-CLN is not required, however for bilateral non-microcarcinoma and the the non-microcarcinoma on the right side, the LN-prRLN-CLN dissection should be conducted.


Asunto(s)
Carcinoma Papilar/cirugía , Escisión del Ganglio Linfático/métodos , Ganglios Linfáticos/cirugía , Neoplasias de la Tiroides/cirugía , Adulto , Carcinoma Papilar/secundario , Neoplasias de los Nervios Craneales/secundario , Femenino , Humanos , Nervios Laríngeos , Ganglios Linfáticos/patología , Metástasis Linfática , Masculino , Persona de Mediana Edad , Nervio Laríngeo Recurrente , Estudios Retrospectivos , Factores de Riesgo , Neoplasias de la Tiroides/patología
4.
Cancer Res ; 55(22): 5288-95, 1995 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-7585590

RESUMEN

The high uptake and prolonged renal retention of monoclonal antibody fragments that are conjugated with radiometal chelates precludes their routine clinical use due to high background counts, which may hinder detection of nearby lesions and/or cause renal radiotoxicity. We report on the potential use of Lys as a pharmacological agent to enhance renal excretion of the [177Lu]alpha-[2-(4-aminophenyl) ethyl]-1,4,7,10-tetraaza-cyclodecane-1,4,7,10-tetraacetic acid CC49 Fab ([177Lu]CC49 Fab) radioimmunoconjugate. The monoclonal antibody portion of this complex is directed toward the tumor-associated glycoprotein-72 antigen. Lys was administered to female BALB/c mice by i.p. injections. [177Lu]CC49 Fab bolus injections were given by the i.v. route. Results of our investigations showed that: (a) kidney radioactivity concentrations were inversely related to Lys dose. The optimal dose (50 mg/mouse) evoked a 3-fold reduction in kidney counts; (b) Lys was most effective when injected 15 min before, or at the same time as, [177Lu]CC49 Fab; (c) the renal effect was both rapid (3-fold decrease at 15 min after injection) and prolonged (4-fold decrease at 24 h after injection); (d) a single Lys dose decreased total body radioactivity by > 2.5-fold; (e) urine excretion of radioactivity was enhanced in Lys-treated mice. High pressure liquid chromatographic analyses using a GF-250 column showed that a large fraction of this urine radioactivity coeluted with a [177Lu]CC49 Fab injection standard. We conclude that Lys enhances the urinary excretion of radioactivity associated with [177Lu]CC49 Fab. These observations warrant further study with regard to the use of amino acids or their derivatives as pharmacological agents to enhance the urinary excretion of small-molecule radioimmunoconjugates.


Asunto(s)
Anticuerpos Monoclonales/farmacocinética , Inmunoconjugados/farmacocinética , Fragmentos Fab de Inmunoglobulinas/metabolismo , Riñón/metabolismo , Lisina/farmacología , Compuestos de Anilina/farmacocinética , Animales , Femenino , Compuestos Heterocíclicos/farmacocinética , Lutecio , Ratones , Ratones Endogámicos BALB C , Radioisótopos , Distribución Tisular
5.
Cancer Res ; 52(22): 6413-7, 1992 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-1423290

RESUMEN

Genetically engineered single-chain Fvs (sFv) are defined as recombinant proteins composed of a variable light chain amino acid sequence of an immunoglobulin tethered to a variable heavy chain sequence by a designed peptide. Previous studies using iodine-labeled sFv, derived from the anticarcinoma monoclonal antibody CC49, showed that the 125I-sFv could efficiently target antigen-positive tumors in a human tumor xenograft model while demonstrating rapid plasma clearance and minimal uptake in normal organs. One of the issues we raised in the analysis of the iodinated sFv metabolic studies was whether similar metabolic patterns would be observed if the sFv were labeled with a radiometal. In the studies reported here, 125I-CC49 sFv and 177Lu-CC49 sFv were co-injected in mice bearing antigen-positive carcinoma xenografts. Both sFv forms showed similar tumor targeting and plasma clearance pharmacokinetics. The 177Lu-sFv, however, showed a greater uptake in liver and spleen and a much higher uptake in kidney. These studies thus demonstrate that despite their small size (M(r) 27,000), the metal-chelated sFv shows a metabolic pattern very different than that of the iodinated sFv, which is most likely due to retention of the metal by organs metabolizing the sFv.


Asunto(s)
Radioisótopos de Yodo , Lutecio , Proteínas de Neoplasias/metabolismo , Radioisótopos , Animales , Anticuerpos Monoclonales/metabolismo , Quelantes/metabolismo , Quelantes/farmacocinética , Cromatografía Líquida de Alta Presión , Neoplasias del Colon/metabolismo , Femenino , Humanos , Cadenas Pesadas de Inmunoglobulina/metabolismo , Cadenas Ligeras de Inmunoglobulina/metabolismo , Región Variable de Inmunoglobulina/metabolismo , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Proteínas Recombinantes/metabolismo , Distribución Tisular
8.
Math Biosci ; 218(2): 98-104, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19563744

RESUMEN

For some diseases, the transmission of infection can cause spatial clustering of disease cases. This clustering has an impact on how one estimates the rate of the spread of the disease and on the design of control strategies. It is, however, difficult to assess such clustering, (local effects on transmission), using traditional statistical methods. A stochastic Markov-chain model that takes into account possible local or more dispersed global effects on the risk of contracting disease is introduced in the context of the transmission dynamics of tuberculosis. The model is used to analyse TB notifications collected in the Asembo and Gem Divisions of Nyanza Province in western Kenya by the Kenya Ministry of Health/National Leprosy and Tuberculosis Program and the Centers for Disease Control and Prevention. The model shows evidence of a pronounced local effect that is significantly greater than the global effect. We discuss a number of variations of the model which identify how this local effect depends on factors such as age and gender. Zoning/clustering of villages is used to identify the influence that zone size has on the model's ability to distinguish local and global effects. An important possible use of the model is in the design of a community randomised trial where geographical clusters of people are divided into two groups and the effectiveness of an intervention policy is assessed by applying it to one group but not the other. Here the model can be used to take the effect of case clustering into consideration in calculating the minimum difference in an outcome variable (e.g. disease prevalence) that can be detected with statistical significance. It thereby gauges the potential effectiveness of such a trial. Such a possible application is illustrated with the given time/spatial TB data set.


Asunto(s)
Modelos Inmunológicos , Mycobacterium tuberculosis/inmunología , Tuberculosis/transmisión , Factores de Edad , Femenino , Humanos , Kenia/epidemiología , Masculino , Cadenas de Markov , Factores Sexuales , Agrupamiento Espacio-Temporal , Tuberculosis/epidemiología , Tuberculosis/inmunología
9.
Histopathology ; 51(4): 528-38, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17880531

RESUMEN

AIMS: To study the expression of adhesion molecules in human liver and their possible roles during hepatocarcinogenesis. METHODS AND RESULTS: The expression of adhesion molecules in normal liver tissues, benign including probable premalignant lesions and malignant lesions was systematically investigated by immunohistochemistry and Western blotting. In normal liver, both hepatocytes and bile duct cells expressed symplekin, desmoglein 1/2, desmocollin 2, desmoplakin and plakophilin 2, but did not express desmocollin 1/3 or plakophilin 1. In benign hepatocyte lesions, expression of the adherens junctions and desmosomes was uniform and slightly increased, but symplekin appeared to show reduced expression in dysplastic lesions. In hepatocellular carcinoma (HCC), the expression of adhesion molecules was often heterogeneous and of abnormal location. Tumour cells with an abnormal distribution or loss of adhesion molecules showed an apolar arrangement of tissue architecture. The expression levels of the adhesion molecules correlated with the differentiation grades of HCC cells. CONCLUSIONS: The decreased expression of symplekin may be an early step in the transformation of hepatocytes, whereas alteration of the expression of adherens junctions and desmosomes may indicate more serious changes.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Moléculas de Adhesión Celular/metabolismo , Polaridad Celular , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Adenoma/metabolismo , Adenoma/patología , Uniones Adherentes/patología , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Desmogleínas/metabolismo , Desmoplaquinas/metabolismo , Desmosomas/patología , Humanos , Hígado/metabolismo , Hígado/patología , Proteínas Nucleares/metabolismo , Placofilinas/metabolismo
10.
Allergol Immunopathol (Madr) ; 18(5): 261-7, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-1982981

RESUMEN

Granulocyte factor derived from the specific granules of polymorphonuclear neutrophils affects mitogen--and alloantigen--induced proliferation of human lymphocytes "in vitro". A dual pattern of GF effect was noted: inhibition of mitogen induced lymphocyte proliferation in higher concentrations and costimulatory activity in lower concentrations of GF. GF induced the lymphocyte proliferation in combination with phorbol ester (PMA) or anti-CD2 monoclonal antibodies (mAb) with PMA. Other combinations of anti-CD2 and anti-CD3 mAb with GF do not augment the proliferation. The comitogenic activities of GF are associated with IL-2 production and IL-2R expression. Specific binding of labelled GF to stimulated lymphocytes suggests that it may recognize the specific molecule expressed only an activated cells. GF diminishes the zymosan-induced granulocyte stimulation, but GF acts as a stimulator of granulocyte O2 production. GF may recognize common targets on leukocytes. Leukocyte adhesive glycoproteins may be such putative targets.


Asunto(s)
Factores Biológicos/farmacología , Linfocitos/efectos de los fármacos , Neutrófilos/efectos de los fármacos , Anticuerpos Monoclonales/farmacología , Antígenos de Diferenciación de Linfocitos T/inmunología , Antígenos de Diferenciación de Linfocitos T/fisiología , Antígenos CD2 , Complejo CD3 , División Celular/efectos de los fármacos , Humanos , Interleucina-2/biosíntesis , Mediciones Luminiscentes , Activación de Linfocitos/efectos de los fármacos , Receptores de Antígenos de Linfocitos T/fisiología , Receptores Inmunológicos/inmunología , Receptores de Interleucina-2/biosíntesis , Transducción de Señal/efectos de los fármacos , Superóxidos/metabolismo , Subgrupos de Linfocitos T/efectos de los fármacos , Acetato de Tetradecanoilforbol/farmacología , Zimosan/antagonistas & inhibidores
11.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 3773-6, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-17271116

RESUMEN

Ventricular assist devices (VADs) have been used successfully as a bridge to transplant in heart failure patients by unloading ventricular volume and restoring the circulation. An artificial vasculature device (AVD) that may better facilitate myocardial recovery than VAD by controlling the afterload seen by the ejecting heart is being developed. The AVD concept is to enable any user-defined input impedance (IM) with resistance (R) and compliance (C) components. In this study, a pulse duplicator was used to test the efficacy of the AVD concept for two control strategies in an adult mock circulation: (1) R-C in series and (2) 2-element Windkessel (R-C in parallel) using instantaneous impedance position control (IIPC) to maintain a desired value or profile of R and C. In vitro experiments were performed and the resulting cardiovascular pressures, volumes, flows, and the afterload (R and C) seen by the LV during ejection for simulated cardiac failure were recorded and analyzed. Our results indicate that setting the AVD to lower IM reduced LV volume and pressure, restored LV stroke volume, and increased coronary flow. The IIPC control algorithms are better suited to maintain any instantaneous IM or an IM profile, but are susceptible to measurement noise.

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