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1.
Neotrop Entomol ; 49(2): 171-178, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31820338

RESUMEN

Many hymenopteran parasitoids are known as biocontrol agents, such as Anisopteromalus calandrae (Howard) (Hymenoptera: Pteromalidae), which is known to parasitize larvae and pupae of coleopteran pests including Lasioderma serricorne (Fabricius) (Coleoptera: Ptinidae). The success of these parasitoids is related to their searching ability, which is mediated through chemical stimuli of the habitat, food, and the progeny of the host itself. This study aimed to assess the chemotaxic responses of A. calandrae comparing the reproductive state of the insects and the experience of wasp females, to different development stages (larvae and pupae) and the presence or absence of the host diet. The chemotaxic responses of A. calandrae individuals at 2 to 4 days old were assessed in a "Y" type olfactometer. Virgin and paired females (without and with previous experience of parasitism) were exposed to larvae of last instar contrasted with pupae and to the diet of L. serricorne. Both virgin and mated males were tested only for diet. Virgin females showed a preference for the diet in contrast to the larvae and to the pupae in contrast to the diet. Paired females without experience choose larvae over diet and made no distinction between pupae and diet. Experienced mated females showed preference for the host to which it had access before, instead of any other alternative option, indicating that there may be changes in the preference through learning.


Asunto(s)
Quimiotaxis , Escarabajos/química , Himenópteros/fisiología , Odorantes , Animales , Escarabajos/parasitología , Dieta , Femenino , Larva , Masculino , Pupa
3.
Minerva Anestesiol ; 78(8): 879-86, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22475805

RESUMEN

BACKGROUND: In the process of risk stratification, a logistic calculation of mortality risk in percentage is easier to interpret. Unfortunately, there is no reliable logistic model available for postoperative intensive care patients. The aim of this study was to present the first logistic model for postoperative mortality risk stratification in cardiac surgical intensive care units. This logistic version is based on our previously presented and established additive model (CASUS) that proved a very high reliability. METHODS: In this prospective study, data from all adult patients admitted to our ICU after cardiac surgery over a period of three years (2007-2009) were collected. The Log-CASUS was developed by weighting the 10 variables of the additive CASUS and adding the number of postoperative day to the model. Risk of mortality is predicted with a logistic regression equation. Statistical performance of the two scores was assessed using calibration (observed/expected mortality ratio), discrimination (area under the receiver operating characteristic curve), and overall correct classification analyses. The outcome measure was ICU mortality. RESULTS: A total of 4054 adult cardiac surgical patients was admitted to the ICU after cardiac surgery during the study period. The ICU mortality rate was 5.8%. The discriminatory power was very high for both additive (0.865-0.966) and logistic (0.874-0.963) models. The logistic model calibrated well from the first until the 13th postoperative day (0.997-1.002), but the additive model over- or underestimated mortality risk (0.626-1.193). CONCLUSION: The logistic model shows statistical superiority. Because of the precise weighing the individual risk factors, it offers a reliable risk prediction. It is easier to interpret and to facilitate the integration of mortality risk stratification into the daily management more than the additive one.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Cuidados Críticos/métodos , Cirugía Torácica/normas , Anciano , Área Bajo la Curva , Procedimientos Quirúrgicos Cardíacos/mortalidad , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Periodo Posoperatorio , Valor Predictivo de las Pruebas , Medición de Riesgo , Resultado del Tratamiento
4.
Br J Radiol ; 84(1003): 649-58, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21697413

RESUMEN

OBJECTIVES: The aim of this study was to determine the disease-specific distribution of brain metastases and, using radiobiological modelling, estimate how these anatomical tendencies might be exploited when delivering prophylactic whole-brain radiotherapy for small cell lung cancer in complete remission. METHODS: Disease-specific brain metastasis atlases were created by mapping brain metastases to a standard image set from a database of patients who were to receive external beam radiation therapy. The specific diseases investigated included lung (both small cell and non-small cell), breast, renal and gynaecological cancers as well as melanoma. Radiobiological modelling was used to estimate how much improvement, in terms of the metastasis-free rate at 3 years, might be possible with non-uniform dose distributions if there are spatial biases in the incidence of micrometastases from small cell lung cancer. RESULTS: For lung and breast cancer, there was an increased probability of cerebellar metastases compared with what would be predicted based solely on brain volume. This trend was not evident for renal cancer, gynaecological malignancies or melanoma. CONCLUSION: Radiobiological models suggest that if there is a non-uniform distribution of microscopic brain metastases in patients with small cell lung cancer, higher population-based metastasis-free rates might be achievable with non-uniform irradiation compared with the same integral whole-brain dose delivered as a uniform prescription.


Asunto(s)
Neoplasias Encefálicas/secundario , Carcinoma de Pulmón de Células no Pequeñas/secundario , Neoplasias Pulmonares/patología , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/radioterapia , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Femenino , Humanos , Neoplasias Pulmonares/radioterapia , Masculino , Modelos Biológicos , Dosificación Radioterapéutica , Inducción de Remisión , Análisis de Supervivencia , Resultado del Tratamiento
5.
Acta Biomater ; 6(2): 702-7, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19602457

RESUMEN

The most common clinical cause of long-term failure in total joint replacement surgery is inflammatory aseptic osteolysis; a condition in which bone surrounding the prosthetic implant, and to which the implant is attached, is resorbed, rendering the artificial device loose and painful. Historically, the severity of this bone resorptive process has been thought to be predominately attributed to the size and shape of wear-debris particles, particularly the metallic particulates that interact biologically/immunologically with cells in the joint. Because the cytotoxic reactions are the result of interactions between the cells and the surfaces of the particulates, it is not clear in the realm of orthopedics to what extent different surface stoichiometric ratios contribute to instigating bioreactive or cytotoxic cellular responses that can lead to aseptic osteolysis. Using energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS), this study presents data and analyses concerning the respective bulk and surface stoichiometric ratios of two commercially pure metal micro-particulates (tantalum and titanium), two prosthetic F75 cobalt-chromium-molybdenum alloy micro-particulates, and prosthetic F136 titanium-aluminum-vanadium alloy micro-particulates, each containing elements common to total joint replacement surgery. Cell culture viability data from four volunteer donors are also presented, which suggest that micro-particulates containing large percentages of surface titanium and aluminum can cause moderate cellular toxicity, and micro-particulates containing large percentages of surface cobalt can result in extremely severe cellular toxicity. This work further suggests that surface analysis techniques, such as XPS, are essential to determine surface elemental characterization of metallic materials prior to interpreting cellular response results.


Asunto(s)
Fibroblastos/efectos de los fármacos , Metales/farmacología , Prótesis e Implantes , Anciano , Femenino , Humanos , Masculino , Metales/química , Microscopía Electrónica de Rastreo , Persona de Mediana Edad , Análisis Espectral/métodos , Rayos X
6.
Colloids Surf B Biointerfaces ; 65(2): 269-75, 2008 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-18583107

RESUMEN

We present data and analyses concerning the cytotoxicity and bioreactivity associated with the surface composition of fine metal particulates that are similar to those commonly released in the body by prostheses used in total joint replacement surgery. Here we study the bulk and surface compositions of three separately procured cobalt-chromium-molybdenum (CoCrMo) micron-sized particulate powders, each identified by their corresponding vendor as being ASTM F75 grade material. We use energy dispersive spectroscopy (EDS) to verify the bulk metallic composition and X-ray photoelectron spectroscopy (XPS) to examine the surface metallic composition of each CoCrMo powder. Cultured synovial fibroblasts were then exposed to the particulate powders to see how the metallic surfaces might affect cellular viability. Results indicate that while the bulk metallic composition of each CoCrMo powder was similar, the surface metallic compositions were found to be dramatically different and yielded equally dramatic differences in terms of cytotoxicity and bioreactivity of synovial fibroblast in culture.


Asunto(s)
Cromo/química , Cobalto/química , Membrana Sinovial/citología , Fibroblastos/citología , Microscopía Electrónica , Análisis Espectral/métodos , Propiedades de Superficie , Rayos X
7.
J Biomed Mater Res A ; 84(4): 1068-77, 2008 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-17685402

RESUMEN

While the industrial community already employs multiple surface analytical techniques to study compositional wearing of various metallic and nonmetallic materials, as yet, these methods have not been widely introduced into the biological community. We report on a novel approach, using the industrial spectroscopic techniques of X-ray photoelectron spectroscopy, micro-Raman spectroscopy, and scanning electron microscopy equipped with energy dispersive spectroscopy, to identify the fine wear particulates and other impurities deposited within the knee-joint following total knee arthroplasty. In this study, synovial fluid was extracted from knee-joints scheduled for revision of total knee arthroplasty. The small debris flake formed by centrifugation of the fluid was analyzed using the spectroscopic techniques mentioned above. These nondestructive techniques were successful in identifying numerous micron and submicron sized metallic particulates that appear to emanate from both the prosthetic bearing (articulating) surfaces and from backside (nonarticulating) surfaces, even when gross wearing of the prosthetic device was not detectable by direct visual inspection intraoperatively. Most interesting is that the ratio of the in vivo metallic debris is approximately the same ratio as that of the manufactured alloy, indicating prosthetic wearing as opposed to chemical dissolution. More importantly, using these spectroscopic techniques to probe both the surface and below the surface of the synovial deposits, we identify an inhomogeneous distribution of the wear debris. This indicates the need to use multiple techniques in order to adequately identify the elemental composition of the prosthetic wear material.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/instrumentación , Ensayo de Materiales/métodos , Metales/química , Falla de Prótesis , Espectrofotometría/métodos , Anciano , Anciano de 80 o más Años , Aleaciones , Femenino , Humanos , Masculino , Estudios Prospectivos , Propiedades de Superficie , Membrana Sinovial/metabolismo , Titanio/química
8.
Colloids Surf B Biointerfaces ; 50(2): 152-9, 2006 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-16797941

RESUMEN

We present data and analyses concerning the adhesion of clinically relevant Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa (bacteria) and Candida albicans (yeast) to Zircaloy-2 (Zry-2) and Zircadyne-705 (Zr705) surfaces. These zirconium-based materials are similar to those now being used in total hip and knee replacements. Here we study clinical strains of microbes under shaken and stationary exposure conditions, and their ability to adhere to Zr surfaces having different oxide thicknesses. We use X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), viable counts, endotoxin assays, and statistical analysis methods, and demonstrate a predictive model for microbial adhesion based on XPS data.


Asunto(s)
Adhesión Bacteriana , Materiales Biocompatibles Revestidos , Circonio , Aleaciones , Candida albicans/fisiología , Adhesión Celular , Recuento de Colonia Microbiana , Endotoxinas/análisis , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Modelos Biológicos , Pseudomonas aeruginosa/fisiología , Análisis Espectral , Staphylococcus aureus/fisiología , Staphylococcus epidermidis/fisiología , Propiedades de Superficie , Rayos X
9.
Brain Res ; 895(1-2): 119-28, 2001 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-11259768

RESUMEN

BACKGROUND: Our laboratory has described the presence of motilin receptors in the rabbit cerebellum. We discovered its presence in the human TE671 cell line, which is of cerebellar origin. METHODS: Cytosolic Ca(2+) fluxes were monitored on a confocal microscope in cells loaded with Indo-1 and stimulated with motilin under various conditions. Binding studies were performed with 125I-[Nle(13)]porcine motilin. Using primers, PCR for the motilin receptor was performed. RESULTS: Cells responded to motilin after 45+/-20 s. At different concentrations of motilin (10(-8), 10(-7), 10(-6.5), 10(-6) and 10(-5) M) the percentage of responding cells was 0+/-0, 0.6+/-1.5, 4.9+/-4.7, 21.7+/-15 and 35.7+/-12, respectively. The response was blocked by the motilin antagonists [Phe(3), Nle(13)]po-motilin (0.8+/-1.8%) and GM-109 (0.0+/-0.0%) and mimicked by the agonist ABT-229 (23.6+/-15%). After stimulation with motilin, ABT-229 or [Phe(3),Leu(13)]po-motilin, but not with the antagonist GM-109, cells were desensitized. The response to motilin persisted in Ca(2+)-free solution (22.8+/-14.7%), was not affected by nifedipine (44+/-11%) but was abolished by incubation with thapsigargin (0+/-0%). Neither ryanodine, nor a previous stimulation with caffeine (0+/-0%) in Ca(2+)-free Krebs, nor both could block the response to motilin (28, 32.0+/-5.7, 41.3+/-6.1%, respectively). Binding studies revealed two binding sites for motilin, with a pK(d) of 8.9+/-0.05 and 6.11+/-0.61 (n=4). There were 100 times more low than high affinity receptors per cell. The presence of receptor mRNA was confirmed by PCR. CONCLUSION: Functional motilin receptors are present in TE671 cells. The response requires intracellular IP(3)-sensitive Ca(2+) stores. These cells may serve as a model of the central motilin receptor.


Asunto(s)
Cerebelo/metabolismo , Motilina/metabolismo , Neuronas/metabolismo , Receptores de la Hormona Gastrointestinal/metabolismo , Receptores de Neuropéptido/metabolismo , Células Tumorales Cultivadas/metabolismo , Señalización del Calcio/efectos de los fármacos , Señalización del Calcio/fisiología , Cerebelo/citología , Cerebelo/efectos de los fármacos , ADN Complementario/metabolismo , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas/fisiología , Humanos , Radioisótopos de Yodo/farmacología , Meduloblastoma , Motilina/agonistas , Motilina/antagonistas & inhibidores , Neuronas/citología , Neuronas/efectos de los fármacos , Norleucina/farmacología , Ensayo de Unión Radioligante , Receptores de la Hormona Gastrointestinal/efectos de los fármacos , Receptores de Neuropéptido/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Taquifilaxis/fisiología , Células Tumorales Cultivadas/citología , Células Tumorales Cultivadas/efectos de los fármacos
10.
Klin Med (Mosk) ; 79(10): 38-41, 2001.
Artículo en Ruso | MEDLINE | ID: mdl-11759406

RESUMEN

Microhemangiomas (MHA) observed on the skin are known under different terms: Tuzhilin's "red drops", senile hemangiomas, Campbell de Morgan spots, scrotal angiokeratomas Fordyce-Satton. Examination of 46 healthy subjects and 241 patients aged 15 to 76 years having different diseases has found that MHA occur both in healthy subjects and patients with different diseases. The number and size of MHA increase with age. The condition seems inheritable. Histologically, MHA are cavernous hemangiomas with thick connective tissue septa making impossible MHA dehematizing in diascopy. The conclusion is made on diagnostic insignificance of skin MHA.


Asunto(s)
Hemangioma Cavernoso/diagnóstico , Enfermedades de la Piel/diagnóstico , Adolescente , Adulto , Anciano , Femenino , Hemangioma Cavernoso/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Enfermedades de la Piel/fisiopatología
11.
Chembiochem ; 2(6): 392-403, 2001 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-11828469

RESUMEN

Life of higher organisms is essentially dependent on the efficient synthesis of ATP by oxidative phosphorylation in mitochondria. An important and as yet unsolved question of energy metabolism is how are the variable rates of ATP synthesis at maximal work load during exercise or mental work and at rest or during sleep regulated. This article reviews our present knowledge on the structure of bacterial and eukaryotic cytochrome c oxidases and correlates it with recent results on the regulatory functions of nuclear-coded subunits of the eukaryotic enzyme, which are absent from the bacterial enzyme. A new molecular hypothesis on the physiological regulation of oxidative phosphorylation is proposed, assuming a hormonally controlled dynamic equilibrium in vivo between two states of energy metabolism, a relaxed state with low ROS (reactive oxygen species) formation, and an excited state with elevated formation of ROS, which are known to accelerate aging and to cause degenerative diseases and cancer. The hypothesis is based on the allosteric ATP inhibition of cytochrome c oxidase at high intramitochondrial ATP/ADP ratios ("second mechanism of respiratory control"), which is switched on by cAMP-dependent phosphorylation and switched off by calcium-induced dephosphorylation of the enzyme.


Asunto(s)
Proteínas Bacterianas/metabolismo , Complejo IV de Transporte de Electrones/metabolismo , Mitocondrias/metabolismo , Fosforilación Oxidativa , Adenosina Trifosfato/metabolismo , Animales , Proteínas Bacterianas/química , Diyodotironinas/metabolismo , Complejo IV de Transporte de Electrones/química , Complejo IV de Transporte de Electrones/clasificación , Corazón/fisiología , Humanos , Potenciales de la Membrana/fisiología , Mitocondrias/enzimología , Modelos Moleculares , Oxígeno/metabolismo , Filogenia , Estructura Terciaria de Proteína , Subunidades de Proteína , Especies Reactivas de Oxígeno/metabolismo
12.
Biol Chem ; 382(12): 1629-36, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11843176

RESUMEN

A new control of mitochondrial membrane potential delta(psi)m and formation of reactive oxygen species (ROS) is presented, based on allosteric ATP-inhibition of cytochrome c oxidase at high intramitochondrial ATP/ADP ratios. Since the rate of ATP synthesis by the ATP synthase is already maximal at low membrane potentials (100-120 mV), the ATP/ADP ratio will also be maximal at this delta(psi)m (at constant rate of ATP consumption). Therefore the control of respiration by the ATP/ADP-ratio keeps delta(psi)m low. In contrast, the known 'respiratory control' leads to an inhibition of respiration only at high delta(psi)m values (150-200 mV) which cause ROS formation. ATP-inhibition of cytochrome c oxidase is switched on and off by reversible phosphorylation (via cAMP and calcium, respectively). We propose that 'stress hormones' which increase intracellular [Ca2+] also increase delta(psi)m and ROS formation, which promote degenerative diseases and accelerate aging.


Asunto(s)
Mitocondrias/fisiología , Especies Reactivas de Oxígeno/metabolismo , Adenosina Trifosfato/metabolismo , Adenosina Trifosfato/fisiología , Regulación Alostérica/fisiología , Secuencia de Aminoácidos , Animales , Respiración de la Célula/fisiología , Secuencia de Consenso , Complejo IV de Transporte de Electrones/antagonistas & inhibidores , Humanos , Potenciales de la Membrana/fisiología , Mitocondrias/metabolismo , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido
13.
Free Radic Biol Med ; 29(3-4): 211-21, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11035249

RESUMEN

A new mechanism on regulation of mitochondrial energy metabolism is proposed on the basis of reversible control of respiration by the intramitochondrial ATP/ADP ratio and slip of proton pumping (decreased H+/e- stoichiometry) in cytochrome c oxidase (COX) at high proton motive force delta p. cAMP-dependent phosphorylation of COX switches on and Ca2+-dependent dephosphorylation switches off the allosteric ATP-inhibition of COX (nucleotides bind to subunit IV). Control of respiration via phosphorylated COX by the ATP/ADP ratio keeps delta p (mainly delta psi(m)) low. Hormone induced Ca2+-dependent dephosphorylation results in loss of ATP-inhibition, increase of respiration and delta p with consequent slip in proton pumping. Slip in COX increases the free energy of reaction, resulting in increased rates of respiration, thermogenesis and ATP-synthesis. Increased delta psi(m) stimulates production of reactive oxygen species (ROS), mutations of mitochondrial DNA and accelerates aging. Slip of proton pumping without dephosphorylation and increase of delta p is found permanently in the liver-type isozyme of COX (subunit VIaL) and at high intramitochondrial ATP/ADP ratios in the heart-type isozyme (subunit VIaH). High substrate pressure (sigmoidal v/s kinetics), palmitate and 3,5-diiodothyronine (binding to subunit Va) increase also delta p, ROS production and slip but without dephosphorylation of COX.


Asunto(s)
Núcleo Celular/genética , Complejo IV de Transporte de Electrones/genética , Complejo IV de Transporte de Electrones/metabolismo , Metabolismo Energético , Mitocondrias/metabolismo , Animales , Respiración de la Célula , Senescencia Celular , Complejo IV de Transporte de Electrones/química , Humanos , Mitocondrias/enzimología , Estrés Oxidativo , Fosforilación , Conformación Proteica , Subunidades de Proteína
14.
FEBS Lett ; 466(1): 130-4, 2000 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-10648827

RESUMEN

In previous studies the allosteric inhibition of cytochrome c oxidase at high intramitochondrial ATP/ADP-ratios via binding of the nucleotides to the matrix domain of subunit IV was demonstrated. Here we show that the allosteric ATP-inhibition of the isolated bovine heart enzyme is switched on by cAMP-dependent phosphorylation with protein kinase A of subunits II (and/or III) and Vb, and switched off by subsequent incubation with protein phosphatase 1. It is suggested that after cAMP-dependent phosphorylation of cytochrome c oxidase mitochondrial respiration is controlled by the ATP/ADP-ratio keeping the proton motive force Deltap low, and the efficiency of energy transduction high. After Ca(2+)-induced dephosphorylation this control is lost, accompanied by increase of Deltap, slip of proton pumping (decreased H(+)/e(-) stoichiometry), and increase of the rate of respiration and ATP-synthesis at a decreased efficiency of energy transduction.


Asunto(s)
Adenosina Trifosfato/antagonistas & inhibidores , AMP Cíclico/metabolismo , Complejo IV de Transporte de Electrones/antagonistas & inhibidores , Adenosina Difosfato/metabolismo , Adenosina Trifosfato/metabolismo , Regulación Alostérica , Animales , Calcio/farmacología , Bovinos , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Complejo IV de Transporte de Electrones/metabolismo , Metabolismo Energético , Técnicas In Vitro , Cinética , Mitocondrias Hepáticas/enzimología , Miocardio/enzimología , Fosforilación
15.
J Neurochem ; 74(2): 478-89, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10646498

RESUMEN

Several variants of the serotonin 5-HT4 receptor are known to be produced by alternative splicing. To survey the existence and usage of exons in humans, we cloned the human 5-HT4 gene. Based on sequence analysis seven C-terminal variants (a-g) and one internal splice variant (h) were found. We concentrated in this study on the functional characterization of the novel splice variant h, which leads to the insertion of 14 amino acids into the second extracellular loop of the receptor. The h variant was cloned as a splice combination with the C-terminal b variant; therefore, we call this receptor 5-HT4(hb). This novel receptor variant was expressed transiently in COS-7 cells, and its pharmacological profile was compared with those of the previously cloned 5-HT4(a) and 5-HT4(b) isoforms, with the latter being the primary reference for the h variant. In competition binding experiments using reference 5-HT4 ligands, no significant differences were detected. However, the broadly used 5-HT4 antagonist GR113808 discriminated functionally among the receptor variants investigated. As expected, it was an antagonist on the 5-HT4(a) and 5-HT4(b) variant but showed partial agonistic activity on the 5-HT4(hb) variant. These data emphasize the importance of variations introduced by splicing for receptor pharmacology and may help in the understanding of conflicting results seen with 5-HT4 ligands in different model systems.


Asunto(s)
Clonación Molecular , ADN Recombinante , Variación Genética , Receptores de Serotonina/genética , Secuencia de Aminoácidos/genética , Animales , Secuencia de Bases/genética , Células COS , Humanos , Datos de Secuencia Molecular , Isoformas de Proteínas/genética , ARN Mensajero/metabolismo , Receptores de Serotonina/metabolismo , Distribución Tisular
16.
J Forensic Sci ; 43(4): 821-6, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9670506

RESUMEN

A benzpyran derivative was linked to the lysines of bovine thyroglobulin (BTG) where 69% of the available lysines were modified. This derivative was designed to elicit antibodies that were directed towards the conserved epitopes of cannabinoid metabolites that appear in urine. Polyclonal antibodies from sheep and goats and murine monoclonal antibodies were generated using this immunogen. The cross-reactivity of the antibodies was compared with antibodies generated from the more traditional phenolic-linked or 9-linked immunogens. An ELISA assay was developed using delta 9-11-nor-9-carboxy-tetrahydrocannabinol (COOH-THC) to obtain a standard curve. The antibodies generated using the benzpyran immunogen showed an average of two to three times higher cross-reactivity towards 11-OH-delta 9-THC, 8 beta-OH-delta 9-THC, 8 alpha-OH-delta 9-THC, 11-OH-delta 8-THC, and 8 beta,11-di-OH-delta 9-THC than antibodies that were generated by traditional cannabinoid immunogens. The selectivity of the benzpyran-elicited antibodies was also compared with antibodies derived from traditional immunogens using clinical urine samples that were confirmed for cannabinoids by GC/MS. The total cross-reactive cannabinoid values obtained with the benzpyran-elicited antibodies were 49% higher than the values obtained using the traditional immunogen structures. The benzpyran immunogen-induced antibodies exhibited the same low cross-reactivity for non-structurally related compounds as antibodies derived from traditional immunogens. The novel benzpyran immunogen used in this study is the first non-cannabinoid immunogen used to generate cannabinoid-selective antibodies and demonstrates the usefulness of such a structure in developing broadly cross-reactive cannabinoid antibodies.


Asunto(s)
Anticuerpos Monoclonales/análisis , Antígenos/inmunología , Benzopiranos/inmunología , Cannabinoides/inmunología , Haptenos/inmunología , Tiroglobulina/inmunología , Animales , Formación de Anticuerpos , Bovinos , Reacciones Cruzadas/inmunología , Ensayo de Inmunoadsorción Enzimática , Femenino , Medicina Legal/métodos , Cabras , Humanos , Ratones , Ratones Endogámicos BALB C , Sensibilidad y Especificidad , Ovinos , Detección de Abuso de Sustancias/métodos
17.
Am J Respir Crit Care Med ; 157(3 Pt 1): 704-9, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9517579

RESUMEN

Osteoporosis is a major complication of long-term corticosteroid administration, but the magnitude of the effect in patients with chronic obstructive pulmonary disease (COPD) is not well defined. In a cross-sectional study, we evaluated the association between steroid use and vertebral fractures in 312 men, 50 yr of age or older, with COPD. Subjects were evaluated according to their corticosteroid use: Never Steroid Users (NSU) (n = 117), Inhaled Steroid Users (ISU) (n = 70), and Systemic Steroid Users (SSU) (n = 125). The prevalence of one or more vertebral fractures was 48.7% in the NSU group, 57.1% in the ISU group, and 63.3% in the SSU group. Compared with NSU, SSU were two times as likely to have one or more vertebral fractures: age-adjusted odds ratio (OR) = 1.80; 95% CI, 1.08 to 3.07. This relationship was primarily due to a strong association between continuous systemic steroid use and vertebral fractures: age-adjusted OR = 2.36; 95% CI, 1.26 to 4.38. In addition, fractures in SSU were more likely to be multiple and more severe. A weaker relationship existed between inhaled steroid use and vertebral fractures: age-adjusted OR = 1.35; 95% CI, 0.77 to 2.56 compared with NSU. These data indicate that vertebral fractures are common in older men with COPD; the likelihood of these fractures is greatest in those men using continuous systemic steroids.


Asunto(s)
Antiinflamatorios/uso terapéutico , Glucocorticoides/uso terapéutico , Enfermedades Pulmonares Obstructivas/tratamiento farmacológico , Fracturas de la Columna Vertebral/inducido químicamente , Administración por Inhalación , Administración Oral , Agonistas Adrenérgicos beta/administración & dosificación , Agonistas Adrenérgicos beta/uso terapéutico , Factores de Edad , Anciano , Antiinflamatorios/administración & dosificación , Beclometasona/administración & dosificación , Beclometasona/uso terapéutico , Intervalos de Confianza , Estudios Transversales , Estudios de Evaluación como Asunto , Volumen Espiratorio Forzado , Glucocorticoides/administración & dosificación , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Osteoporosis/inducido químicamente , Prednisona/administración & dosificación , Prednisona/uso terapéutico , Prevalencia , Fumar/fisiopatología , Triamcinolona Acetonida/administración & dosificación , Triamcinolona Acetonida/uso terapéutico , Capacidad Vital
18.
Oncogene ; 14(6): 741-3, 1997 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-9038382

RESUMEN

Chromosomal losses involving the short arm of chromosome 8 are frequent in a variety of tumor types, including breast cancer, suggesting the presence of one or more tumor suppressor genes in this region. Previous linkage analysis and studies of loss of heterozygosity (LOH) have suggested the presence of a putative third breast cancer susceptibility gene around D8S505 at 8p12-p22. We have performed linkage analysis in two German breast cancer families, showing negative lod scores with 17q and 13q markers, using seven adjacent microsatellite markers from 8p12-p22. Incorporating LOH data from tumors of the affected family members a maximum cumulative three-point lod score of 3.30 at theta = 0.00 was obtained with D8S137 and D8S131. Our findings considerably strengthen the evidence for a third breast cancer susceptibility locus (BRCA3) mapping to the short arm of human chromosome 8.


Asunto(s)
Neoplasias de la Mama/genética , Cromosomas Humanos Par 8 , Ligamiento Genético , Adulto , Susceptibilidad a Enfermedades , Femenino , Eliminación de Gen , Humanos , Masculino , Persona de Mediana Edad , Linaje
19.
J Cancer Res Clin Oncol ; 123(1): 69-70, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-8996544

RESUMEN

More than 100 mutations have been described for the breast-cancer-susceptibility gene BRCA1. The paper describes phenotypical aspects of three selected mutations located at the beginning, in the middle, and at the end of the gene. A remarkable decrease of the age of diagnosis of the mammary carcinoma is observed with increasing length of the putative gene product, combined with greater severity of the disease.


Asunto(s)
Neoplasias de la Mama/genética , Genes BRCA1/genética , Mutación/genética , Adulto , Femenino , Humanos , Persona de Mediana Edad , Fenotipo , Pronóstico , Eliminación de Secuencia
20.
Br J Cancer ; 76(8): 983-91, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9376278

RESUMEN

We have identified a high frequency of loss of heterozygosity (LOH) on the human chromosome region 8p12-p22 in a panel of microdissected familial (86% LOH) and sporadic (74% LOH) breast tumours. The two most frequently deleted regions were defined around marker D8S133 and in a broader centromeric region bounded by markers D8S137 and D8S339. We cannot unequivocally characterize the 8p12-p22 loss as an early or a late event in breast carcinogenesis. In parallel, we have performed linkage analysis in four German breast cancer families. A location score greater than 13.67 corresponding to a LOD score of 2.97 at the marker D8S137 has been obtained. Our results considerably strengthen the evidence for a breast cancer susceptibility gene(s) located on the short arm of the chromosome region at 8p12-p22.


Asunto(s)
Neoplasias de la Mama/genética , Cromosomas Humanos Par 8 , Ligamiento Genético , Pérdida de Heterocigocidad , Adulto , Anciano , Neoplasias de la Mama/patología , Mapeo Cromosómico , Salud de la Familia , Femenino , Eliminación de Gen , Humanos , Repeticiones de Microsatélite , Persona de Mediana Edad
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