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1.
Anaesthesia ; 77(12): 1368-1375, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36066179

RESUMEN

Bougie impingement during tracheal intubation can increases the likelihood of prolonged intubation time, failed intubation and airway trauma. A flexible tip bougie may overcome this problem, which can occur when using a non-channelled, hyperangulated videolaryngoscope with a standard bougie. This randomised controlled study compared standard and flexible tip bougies using a non-channelled videolaryngoscope (C-MAC® D-blade) in 160 patients. The primary outcome measure was the modified intubation difficulty scale score. Secondary outcome measures were: laryngoscopy time; total tracheal intubation time; first attempt success rate; and postoperative sore throat verbal rating score. The median (IQR [range]) modified intubation difficulty scale scores for standard bougie and flexible tip bougie were 1 (0-2[0-5]) and 0 (0-1[0-3]), respectively (p = 0.001). There was no significant differences in laryngoscopy time, total tracheal intubation time, first attempt success rate and postoperative sore throat between the two groups. Both the flexible tip and standard bougies can be used with a high first attempt success rate for tracheal intubation using a C-MAC D-blade videolaryngoscope. The flexible tip bougie demonstrated a significantly better modified intubation difficulty scale score and lower incidence of bougie impingement.


Asunto(s)
Laringoscopios , Faringitis , Humanos , Intubación Intratraqueal/efectos adversos , Laringoscopía , Faringitis/epidemiología , Faringitis/etiología , Tráquea , Grabación en Video
2.
Psychol Med ; 46(13): 2785-97, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27429183

RESUMEN

BACKGROUND: Anorexia nervosa (AN) and body dysmorphic disorder (BDD) frequently co-occur, and have several overlapping phenomenological features. Little is known about their shared neurobiology. The aim of the study was to compare modular organization of brain structural connectivity. METHOD: We acquired diffusion-weighted magnetic resonance imaging data on unmedicated individuals with BDD (n = 29), weight-restored AN (n = 24) and healthy controls (HC) (n = 31). We constructed connectivity matrices using whole-brain white matter tractography, and compared modular structures across groups. RESULTS: AN showed abnormal modularity involving frontal, basal ganglia and posterior cingulate nodes. There was a trend in BDD for similar abnormalities, but no significant differences compared with AN. In AN, poor insight correlated with longer path length in right caudal anterior cingulate and right posterior cingulate. CONCLUSIONS: Abnormal network organization patterns in AN, partially shared with BDD, may have implications for understanding integration between reward and habit/ritual formation, as well as conflict monitoring/error detection.


Asunto(s)
Anorexia Nerviosa/diagnóstico por imagen , Ganglios Basales/diagnóstico por imagen , Trastorno Dismórfico Corporal/diagnóstico por imagen , Conectoma , Giro del Cíngulo/diagnóstico por imagen , Corteza Prefrontal/diagnóstico por imagen , Adolescente , Adulto , Peso Corporal , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Masculino , Adulto Joven
3.
Psychol Med ; 45(16): 3491-503, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26219399

RESUMEN

BACKGROUND: Body dysmorphic disorder (BDD) and anorexia nervosa (AN) are both characterized by distorted perception of appearance. Previous studies in BDD suggest abnormalities in visual processing of own and others' faces, but no study has examined visual processing of faces in AN, nor directly compared the two disorders in this respect. METHOD: We collected functional magnetic resonance imaging data on 60 individuals of equivalent age and gender in each of three groups--20 BDD, 20 weight-restored AN, and 20 healthy controls (HC)--while they viewed images of others' faces that contained only high or low spatial frequency information (HSF or LSF). We tested hypotheses about functional connectivity within specialized sub-networks for HSF and LSF visual processing, using psychophysiological interaction analyses. RESULTS: The BDD group demonstrated increased functional connectivity compared to HC between left anterior occipital face area and right fusiform face area (FFA) for LSF faces, which was associated with symptom severity. Both BDD and AN groups had increased connectivity compared to HC between FFA and precuneous/posterior cingulate gyrus for LSF faces, and decreased connectivity between FFA and insula. In addition, we found that LSF connectivity between FFA and posterior cingulate gyrus was significantly associated with thoughts about own appearance in AN. CONCLUSIONS: Results suggest similar abnormal functional connectivity within higher-order systems for face processing in BDD and AN, but distinct abnormal connectivity patterns within occipito-temporal visual networks. Findings may have implications for understanding relationships between these disorders, and the pathophysiology underlying perceptual distortions.


Asunto(s)
Anorexia Nerviosa/fisiopatología , Trastorno Dismórfico Corporal/fisiopatología , Corteza Cerebral/fisiopatología , Reconocimiento Facial , Distorsión de la Percepción , Adolescente , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Adulto Joven
4.
In Silico Biol ; 11(1-2): 61-81, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22475752

RESUMEN

ChemModLab, written by the ECCR @ NCSU consortium under NIH support, is a toolbox for fitting and assessing quantitative structure-activity relationships (QSARs). Its elements are: a cheminformatic front end used to supply molecular descriptors for use in modeling; a set of methods for fitting models; and methods for validating the resulting model. Compounds may be input as structures from which standard descriptors will be calculated using the freely available cheminformatic front end PowerMV; PowerMV also supports compound visualization. In addition, the user can directly input their own choices of descriptors, so the capability for comparing descriptors is effectively unlimited. The statistical methodologies comprise a comprehensive collection of approaches whose validity and utility have been accepted by experts in the fields. As far as possible, these tools are implemented in open-source software linked into the flexible R platform, giving the user the capability of applying many different QSAR modeling methods in a seamless way. As promising new QSAR methodologies emerge from the statistical and data-mining communities, they will be incorporated in the laboratory. The web site also incorporates links to public-domain data sets that can be used as test cases for proposed new modeling methods. The capabilities of ChemModLab are illustrated using a variety of biological responses, with different modeling methodologies being applied to each. These show clear differences in quality of the fitted QSAR model, and in computational requirements. The laboratory is web-based, and use is free. Researchers with new assay data, a new descriptor set, or a new modeling method may readily build QSAR models and benchmark their results against other findings. Users may also examine the diversity of the molecules identified by a QSAR model. Moreover, users have the choice of placing their data sets in a public area to facilitate communication with other researchers; or can keep them hidden to preserve confidentiality.


Asunto(s)
Informática/métodos , Internet , Relación Estructura-Actividad Cuantitativa , Minería de Datos , Modelos Moleculares , Redes Neurales de la Computación , Programas Informáticos , Máquina de Vectores de Soporte
5.
Psychol Med ; 41(11): 2385-97, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21557897

RESUMEN

BACKGROUND: Individuals with body dysmorphic disorder (BDD) may have perceptual distortions for their appearance. Previous studies suggest imbalances in detailed relative to configural/holistic visual processing when viewing faces. No study has investigated the neural correlates of processing non-symptom-related stimuli. The objective of this study was to determine whether individuals with BDD have abnormal patterns of brain activation when viewing non-face/non-body object stimuli. METHOD: Fourteen medication-free participants with DSM-IV BDD and 14 healthy controls participated. We performed functional magnetic resonance imaging (fMRI) while participants matched photographs of houses that were unaltered, contained only high spatial frequency (HSF, high detail) information or only low spatial frequency (LSF, low detail) information. The primary outcome was group differences in blood oxygen level-dependent (BOLD) signal changes. RESULTS: The BDD group showed lower activity in the parahippocampal gyrus, lingual gyrus and precuneus for LSF images. There were greater activations in medial prefrontal regions for HSF images, although no significant differences when compared to a low-level baseline. Greater symptom severity was associated with lower activity in the dorsal occipital cortex and ventrolateral prefrontal cortex for normal spatial frequency (NSF) and HSF images. CONCLUSIONS: Individuals with BDD have abnormal brain activation patterns when viewing objects. Hypoactivity in visual association areas for configural and holistic (low detail) elements and abnormal allocation of prefrontal systems for details are consistent with a model of imbalances in global versus local processing. This may occur not only for appearance but also for general stimuli unrelated to their symptoms.


Asunto(s)
Trastorno Dismórfico Corporal/fisiopatología , Encéfalo/fisiopatología , Trastornos de la Percepción/fisiopatología , Distorsión de la Percepción , Percepción Visual , Adulto , Mapeo Encefálico , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Análisis por Apareamiento , Persona de Mediana Edad
6.
Linear Algebra Appl ; 433(3): 681-689, 2010 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-23966751

RESUMEN

The Euclidean distance matrix for n distinct points in ℝ r is generically of rank r + 2. It is shown in this paper via a geometric argument that its nonnegative rank for the case r = 1 is generically n.

7.
Numer Algorithms ; 53(4): 419-437, 2010 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-25392603

RESUMEN

In the past decade or so, semi-definite programming (SDP) has emerged as a powerful tool capable of handling a remarkably wide range of problems. This article describes an innovative application of SDP techniques to quadratic inverse eigenvalue problems (QIEPs). The notion of QIEPs is of fundamental importance because its ultimate goal of constructing or updating a vibration system from some observed or desirable dynamical behaviors while respecting some inherent feasibility constraints well suits many engineering applications. Thus far, however, QIEPs have remained challenging both theoretically and computationally due to the great variations of structural constraints that must be addressed. Of notable interest and significance are the uniformity and the simplicity in the SDP formulation that solves effectively many otherwise very difficult QIEPs.

8.
Science ; 214(4526): 1246-8, 1981 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-6272398

RESUMEN

"Small cells" or "oat cells" characterize a virulent form of lung cancer and share many biochemical properties with peptide-secreting neurones. The neuropeptide bombesin is present in all small-cell lines examined, but not in other lung cancer cell lines, suggesting that bombesinergic precursor cells in lung may give rise to this disease.


Asunto(s)
Bombesina/análisis , Carcinoma de Células Pequeñas/análisis , Neoplasias Pulmonares/análisis , Péptidos/análisis , Adenocarcinoma/análisis , Carcinoma de Células Escamosas/análisis , Línea Celular , Humanos , Mesotelioma/análisis
9.
Neuron ; 17(3): 475-82, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8816710

RESUMEN

beta-Adrenergic receptor activation has a central role in the enhancement of memory formation that occurs during heightened states of emotional arousal. Although beta-adrenergic receptor activation may enhance memory formation by modulating long-term potentiation (LTP), a candidate synaptic mechanism involved in memory formation, the cellular basis of this modulation is not fully understood. Here, we report that, in the CA1 region of the hippocampus, beta-adrenergic receptor activation selectively enables the induction of LTP during long trains of 5 Hz synaptic stimulation. Protein phosphatase inhibitors mimic the effects of beta-adrenergic receptor activation on 5 Hz stimulation-induced LTP, suggesting that activation of noradrenergic systems during emotional arousal may enhance memory formation by inhibiting protein phosphatases that normally oppose the induction of LTP.


Asunto(s)
Hipocampo/fisiología , Potenciación a Largo Plazo/fisiología , Receptores Adrenérgicos beta/fisiología , Animales , Estimulación Eléctrica , Electrofisiología , Hipocampo/química , Hipocampo/citología , Ratones , Ratones Endogámicos C57BL , Células Piramidales/fisiología
10.
J Clin Invest ; 97(3): 806-13, 1996 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-8609238

RESUMEN

Signal transduction pathways shared by different autocrine growth factors may provide an efficient approach to accomplish clinically significant control of lung cancer growth. In this study, we demonstrate that two autocrine growth factors activate 5-lipoxygenase action of the arachidonic acid metabolic pathway in lung cancer cell lines. Both growth factors increased the production of 5(S)-hydrooxyeicosa-6E,8Z,11Z,14Z-tetraeno ic acid (5-HETE), a major early 5-lipoxygenase metabolic product. Exogenously added 5-HETE stimulated lung cancer cell growth in vitro. Inhibition of 5-lipoxygenase metabolism by selective antagonists resulted in significant growth reduction for a number of lung cancer cell lines. Primary clinical specimens and lung cancer cell lines express the message for the 5-lipoxygenase enzymes responsible for the generation of active metabolites. In vivo evaluation demonstrated that interruption of 5-lipoxygenase signaling resulted in enhanced levels of programmed cell death. These findings demonstrate that 5-lipoxygenase activation is involved with growth factor-mediated growth stimulation for lung cancer cell lines. Pharmacological intervention with lipoxygenase inhibitors may be an important new clinical strategy to regulate growth factor-dependent stages of lung carcinogenesis.


Asunto(s)
Araquidonato 5-Lipooxigenasa/biosíntesis , Carcinoma de Células Pequeñas/metabolismo , Sustancias de Crecimiento/farmacología , Neoplasias Pulmonares/metabolismo , Transducción de Señal , Proteínas Activadoras de la 5-Lipooxigenasa , Animales , Araquidonato 5-Lipooxigenasa/genética , Ácido Araquidónico/antagonistas & inhibidores , Ácido Araquidónico/metabolismo , Secuencia de Bases , Carcinoma de Células Pequeñas/tratamiento farmacológico , Proteínas Portadoras/biosíntesis , Proteínas Portadoras/genética , División Celular/efectos de los fármacos , Péptido Liberador de Gastrina , Inhibidores de la Lipooxigenasa/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Masoprocol/uso terapéutico , Proteínas de la Membrana/biosíntesis , Proteínas de la Membrana/genética , Ratones , Ratones Desnudos , Datos de Secuencia Molecular , Péptidos/farmacología , ARN Mensajero/análisis , Somatomedinas/farmacología
11.
Br J Pharmacol ; 151(1): 63-72, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17351657

RESUMEN

BACKGROUND AND PURPOSE: Angiogenesis involves multiple signaling pathways that must be considered when developing agents to modulate pathological angiogenesis. Because both cyclooxygenase inhibitors and dithioles have demonstrated anti-angiogenic properties, we investigated the activities of a new class of anti-inflammatory drugs containing dithiolethione moieties (S-NSAIDs) and S-valproate. EXPERIMENTAL APPROACH: Anti-angiogenic activities of S-NSAIDS, S-valproate, and the respective parent compounds were assessed using umbilical vein endothelial cells, muscle and tumor tissue explant angiogenesis assays, and developmental angiogenesis in Fli:EGFP transgenic zebrafish embryos. KEY RESULTS: Dithiolethione derivatives of diclofenac, valproate, and sulindac inhibited endothelial cell proliferation and induced Ser(78) phosphorylation of hsp27, a known molecular target of anti-angiogenic signaling. The parent drugs lacked this activity, but dithiolethiones were active at comparable concentrations. Although dithiolethiones can potentially release hydrogen sulphide, NaSH did not reproduce some activities of the S-NSAIDs, indicating that the dithioles regulate angiogenesis through mechanisms other than release of H(2)S. In contrast to the parent drugs, S-NSAIDs, S-valproate, NaSH, and dithiolethiones were potent inhibitors of angiogenic responses in muscle and HT29 tumor explants assessed by 3-dimensional collagen matrix assays. Dithiolethiones and valproic acid were also potent inhibitors of developmental angiogenesis in zebrafish embryos, but the S-NSAIDs, remarkably, lacked this activity. CONCLUSIONS AND IMPLICATION: S-NSAIDs and S-valproate have potent anti-angiogenic activities mediated by their dithiole moieties. The novel properties of S-NSAIDs and S-valproate to inhibit pathological versus developmental angiogenesis suggest that these agents may have a role in cancer treatment.


Asunto(s)
Anetol Tritiona/farmacología , Inhibidores de la Angiogénesis/farmacología , Antiinflamatorios no Esteroideos/farmacología , Ácido Valproico/farmacología , Animales , Proliferación Celular/efectos de los fármacos , Células Endoteliales/citología , Células Endoteliales/efectos de los fármacos , Proteínas de Choque Térmico HSP27 , Proteínas de Choque Térmico/metabolismo , Humanos , Ratones , Ratones Endogámicos C57BL , Fosforilación , Solubilidad , Pez Cebra
12.
Transl Psychiatry ; 7(9): e1230, 2017 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-28872637

RESUMEN

Cognitive-behavioral therapy (CBT) is effective for obsessive compulsive disorder (OCD); however, little is understood about its mechanisms related to brain network connectivity. We examined connectivity changes from resting-state functional magnetic resonance imaging data pre-to-post-CBT in 43 OCD participants, randomized to receive either 4 weeks of intensive CBT or 4 weeks waitlist followed by 4 weeks of CBT, and 24 healthy controls before and after 4 weeks of no treatment. Network-based-statistic analysis revealed large-magnitude increases in OCD connectivity in eight networks. Strongest increases involved connectivity between the cerebellum and caudate/putamen, and between the cerebellum and dorsolateral/ventrolateral prefrontal cortices. Connectivity increases were associated with increased resistance to compulsions. Mechanisms of CBT may involve enhanced cross-network integration, both within and outside of classical cortico-striatal-thalamo-cortical regions; those involving cerebellar to striatal and prefrontal regions may reflect acquisition of new non-compulsive goal-directed behaviors and thought patterns. Our findings have implications for identifying targets for enhancing treatment efficacy and monitoring treatment progress.


Asunto(s)
Cerebelo/fisiopatología , Terapia Cognitivo-Conductual/métodos , Conectoma/métodos , Neostriado/fisiopatología , Red Nerviosa/fisiopatología , Trastorno Obsesivo Compulsivo/fisiopatología , Trastorno Obsesivo Compulsivo/terapia , Evaluación de Resultado en la Atención de Salud/métodos , Corteza Prefrontal/fisiopatología , Adulto , Cerebelo/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Neostriado/diagnóstico por imagen , Red Nerviosa/diagnóstico por imagen , Trastorno Obsesivo Compulsivo/diagnóstico por imagen , Corteza Prefrontal/diagnóstico por imagen , Adulto Joven
13.
Trends Neurosci ; 24(12): 687-90, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11718856

RESUMEN

Neuropeptides 2001, 2nd Joint Meeting of the European Neuropeptide Club and the American Summer Neuropeptide Conference (11th Annual Meeting). 6-11 May 2001 with Satellite Symposium, Israeli-French Symposium, Israel Ministry of Science, Culture and Sport, 6 May 2001, held at Maale Hachmicha and Tel Aviv University, Israel.


Asunto(s)
Química Encefálica/fisiología , Neuropéptidos/fisiología , Animales
14.
Panminerva Med ; 48(1): 19-26, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16633328

RESUMEN

Several peptide hormones have been identified which alter the proliferation of lung cancer. Small cell lung cancer (SCLC), which is a neuroendocrine cancer, produces and secretes gastrin releasing peptide (GRP), neurotensin (NT) and adrenomedullin (AM) as autocrine growth factors. GRP, NT and AM bind to G-protein coupled receptors causing phosphatidylinositol turnover or elevated cAMP in SCLC cells. Addition of GRP, NT or AM to SCLC cells causes altered expression of nuclear oncogenes, such as c-fos, and stimulation of growth. Antagonists have been developed for GRP, NT and AM receptors which function as cytostatic agents and inhibit SCLC growth. Growth factor antagonists, such as the NT1 receptor antagonist SR48692, facilitate the ability of chemotherapeutic drugs to kill lung cancer cells. It remains to be determined if GRP, NT and AM receptors will served as molecular targets, for development of new therapies for the treatment of SCLC patients. Non-small cell lung cancer (NSCLC) cells also have a high density of GRP, NT, AM and epidermal growth factor (EGF) receptors. Several NSCLC patients with EGF receptor mutations respond to gefitinib, a tyrosine kinase inhibitor. Gefitinib relieves NSCLC symptoms, maintaining stable disease in patients who are not eligible for systemic chemotherapy. It is important to develop new therapeutic approaches using translational research techniques for the treatment of lung cancer patients.


Asunto(s)
Neoplasias Pulmonares/metabolismo , Hormonas Peptídicas/metabolismo , Adrenomedulina , Secuencia de Aminoácidos , Carcinoma de Pulmón de Células no Pequeñas/etiología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Células Pequeñas/etiología , Carcinoma de Células Pequeñas/metabolismo , Péptido Liberador de Gastrina/genética , Péptido Liberador de Gastrina/metabolismo , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/etiología , Datos de Secuencia Molecular , Neurotensina/genética , Neurotensina/metabolismo , Hormonas Peptídicas/genética , Péptidos/genética , Péptidos/metabolismo
15.
Cancer Res ; 53(21): 5214-8, 1993 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-8221658

RESUMEN

The effect of thymosin alpha 1 (THN alpha 1) and its NH2-terminal fragment (THN1-14) and COOH-terminal fragment (THN15-28) on non-small cell lung cancer (NSCLC) growth was evaluated. Using an anti-THN alpha 1 antibody, receptors were identified on NSCLC cells that were pretreated with 10(-6) M THN alpha 1. [3H]Arachidonic acid was readily taken up by NSCLC cells and THN alpha 1 significantly increased the rate of arachidonic acid release. THN1-15 slightly stimulated but THN15-28 and THN beta 4 did not alter arachidonic acid release from NCI-H1299 cells. In clonogenic growth assays in vitro, THN alpha 1 (10(-6) M) significantly decreased NSCLC colony number whereas THN1-14, THN15-28, and THN beta 4 were less potent. Using growth assays in vivo, THN alpha 1 (10 micrograms s.c./day) but not THN1-14, THN15-28, or THN beta 4 inhibited significantly NSCLC xenograft formation in nude mice. These data suggest that biologically active THN alpha 1 receptors are present on NSCLC cells and that native THN alpha 1 inhibits the growth of human NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/patología , División Celular/efectos de los fármacos , Neoplasias Pulmonares/patología , Timosina/análogos & derivados , Animales , Ácido Araquidónico/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Línea Celular , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Inmunohistoquímica , Cinética , Neoplasias Pulmonares/metabolismo , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Fragmentos de Péptidos/farmacología , Timalfasina , Timosina/farmacología , Trasplante Heterólogo , Células Tumorales Cultivadas , Ensayo de Tumor de Célula Madre
16.
Cancer Res ; 47(3): 821-5, 1987 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-3026617

RESUMEN

Human small cell lung cancers (SCLC) produce and secrete the regulatory peptide bombesin (BN) or its mammalian counterpart gastrin-releasing peptide (GRP). In addition, several SCLC tumor lines have been shown to express high affinity receptors for BN/GRP. On the basis of these findings, we investigated the effect of exogenously added BN and GRP on the soft agarose colony growth of a panel of human cell lines. In serum-free defined medium, colony formation of 9 of 10 SCLC cell lines was stimulated up to 150-fold by BN or GRP, with peak colony stimulation observed at 50 nM BN. In contrast, no stimulatory effect of BN was observed on nine non-SCLC cell lines. Although no stimulation of colony growth by BN was seen in serum-supplemented medium, addition of BN to the serum-free medium increased cloning efficiency to that achieved by serum in most of the SCLC cell lines. GRP 1-27, the active mammalian analogue of Bn, stimulated colony growth of SCLC cells similar to the manner of BN, while the physiologically inactive BN analogue, des-Leu (13)-Met (14)-BN, had no effect on colony growth. No correlation was observed in SCLC cell lines between the response of these cells to exogenous BN and the amount of cellular BN/GRP produced or the presence of BN receptors. These data suggest that BN/GRP may in some instances function as an autocrine growth factor for SCLC and indicate new ways for modulating SCLC growth in patients with this tumor.


Asunto(s)
Bombesina/farmacología , Carcinoma de Células Pequeñas/patología , Polipéptido Inhibidor Gástrico/farmacología , Neoplasias Pulmonares/patología , Adenocarcinoma/patología , División Celular/efectos de los fármacos , Línea Celular , Células Clonales , Humanos , Melanoma/patología
17.
Cancer Res ; 46(3): 1214-8, 1986 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3002612

RESUMEN

Bombesin/gastrin releasing peptide-like immunoreactivity (BLI) is found in the majority of small cell carcinoma of the lung (SCCL) cell lines examined. Because BLI is present in high concentration in SCCL we studied the mechanism of BLI secretion from several SCCL cell lines and in patients with SCCL. In cell line NCI-H345 the structurally related polypeptide hormones secretin, vasoactive intestinal peptide, and peptide histidine isoleucine as well as theophylline, a phosphodiesterase inhibitor, N6,O2'-dibutyryl cyclic adenosine 3':5'-monophosphate, a cyclic nucleotide analogue, increased BLI release by 16-120% and cyclic adenosine 3':5'-monophosphate by 36-350%. Similar results were obtained in SCCL cell line NCI-H209. i.v. injection of secretin (2 units/kg) significantly increased plasma BLI in 2 patients with extrapulmonary SCCL. These data suggest that SCCL cells possess receptors for secretin/vasoactive intestinal peptide and that receptor occupation stimulates in vitro and in vivo BLI secretion.


Asunto(s)
Bombesina/metabolismo , Carcinoma de Células Pequeñas/metabolismo , Neoplasias Pulmonares/metabolismo , Péptidos/metabolismo , Secretina/farmacología , Tasa de Secreción/efectos de los fármacos , Péptido Intestinal Vasoactivo/farmacología , Alprostadil/farmacología , Bucladesina/farmacología , AMP Cíclico/metabolismo , Péptido Liberador de Gastrina , Humanos , Péptido PHI , Péptidos/farmacología , Teofilina/farmacología , Factores de Tiempo
18.
Cancer Res ; 59(18): 4578-83, 1999 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-10493511

RESUMEN

Sigma receptors are known to be expressed in a variety of human tumor cells, including breast, neural, and melanoma tumors. A very high density (1.0-1.5 million receptors/cell) of sigma receptors was also reported in a human androgen-dependent prostate tumor cell line (LNCaP). In this study, we show that a very high density of sigma receptors is also expressed in an androgen-independent human prostate tumor cell line (DU-145). Pharmacological binding studies using the sigma-1-selective ligand [3H](+)-pentazocine showed a high-affinity binding (Kd = 5.80 nM, Bmax = 1800 fmol/mg protein). Similarly, binding studies with [3H]1,3-di-o-tolylguanidine in the presence of dextrallorphan also showed a high-affinity binding (Kd = 15.71 nM, Bmax = 1930 fmol/mg protein). Radioiodinated benzamide N-[2-(1'-piperidinyl)ethyl]-3-[125I]iodo-4-methoxybenzamide ([125I]PIMBA) was also shown to bind DU-145 cells in a dose-dependent manner. Three different radioiodinated benzamides, [125I]PIMBA, 4-[125I]iodo-N-[2-(1'-piperidinyl)ethyl]benzamide, and 2-[125I]-N-(N-benzylpiperidin-4-yl)-2-iodobenzamide, were screened for their potential to image human prostate tumors in nude mice bearing human prostate cells (DU-145) xenografts. All three compounds showed a fast clearance from the blood pool and a high uptake and retention in the tumor. Therapeutic potential of nonradioactive PIMBA was studied using in vitro colonogenic assays. A dose-dependent inhibition of cell colony formation was found in two different human prostate cells. These results demonstrate the potential use of sigma receptor binding ligands in non-invasive diagnostic imaging of prostate cancer and its treatment.


Asunto(s)
Benzamidas/farmacocinética , Benzamidas/uso terapéutico , Radioisótopos de Yodo/farmacocinética , Piperidinas/farmacocinética , Neoplasias de la Próstata/diagnóstico , Receptores sigma/análisis , Animales , Antineoplásicos/uso terapéutico , Unión Competitiva , Encéfalo/metabolismo , Membrana Celular/metabolismo , Cobayas , Humanos , Levalorfano/farmacología , Hígado/metabolismo , Masculino , Ratones , Ratones Desnudos , Pentazocina/farmacocinética , Neoplasias de la Próstata/tratamiento farmacológico , Ratas , Receptores sigma/metabolismo , Distribución Tisular , Trasplante Heterólogo , Células Tumorales Cultivadas
19.
Cancer Res ; 52(9 Suppl): 2732s-2736s, 1992 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-1563005

RESUMEN

Previously, high levels of gastrin-releasing peptide and its mRNA were detected in classic small cell lung cancer cell lines. Here the ability of lung cancer cell lines to synthesize neuromedin B (NMB), a structurally similar mammalian bombesin-like peptide, was investigated. By radioimmunoassay, NMB (0.1-0.7 pmol/mg of protein) was detected in 23 of 33 lung cancer cell lines. In contrast, gastrin-releasing peptide (0.1-12.9 pmol/mg of protein) was detected in 16 of 32 cell lines. Using gel filtration and high pressure liquid chromatography techniques, the main peak of immunoreactive NMB coeluted with synthetic NMB. By Northern analysis, a 0.8-kilobase mRNA species was present, using poly(A) mRNA derived from two of three lung cancer cell lines. Using a more sensitive S1 nuclease protection assay, NMB mRNA was present in most of the 15 lung cancer cell lines examined. These data suggest that NMB may be a regulatory peptide in lung cancer.


Asunto(s)
Neoplasias Pulmonares/metabolismo , Neuroquinina B/análogos & derivados , Northern Blotting , Humanos , Neoplasias Pulmonares/genética , Neuroquinina B/biosíntesis , Neuroquinina B/genética , ARN Mensajero/análisis , ARN Neoplásico/análisis , Radioinmunoensayo , Células Tumorales Cultivadas
20.
Cancer Res ; 55(21): 4886-91, 1995 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-7585525

RESUMEN

We have identified pituitary adenylate cyclase activating peptide (PACAP) receptors on small cell lung cancer cell line NCI-N417 in a previous study. In this study, the role of PACAP in the growth and signal transduction of non-small cell lung cancer cells was investigated. Northern blot analysis with a full-length human PACAP receptor cDNA probe revealed a major 7.5-kb hybridizing transcript when total RNA extracted from NCI-H838 cells was used. PACAP bound with high affinity (Kd = 1 nM) to a single class of sites (Bmax = 14,000/cell) when NCI-H838 cells were used. Specific 125I-labeled PACAP binding was inhibited with high affinity by PACAP-27 and PACAP-38, with moderate affinity by PACAP(6-38), and with low affinity by vasoactive intestinal polypeptide, PACAP(28-38), and PACAP(16-38). PACAP-27 elevated cAMP in a dose-dependent manner, and the increase in cAMP caused by PACAP was reversed by PACAP(6-38). PACAP-27, but not vasoactive intestinal polypeptide, elevated cytosolic Ca2+ in individual NCI-H838 cells. PACAP-27 stimulated arachidonic acid release, and the increase caused by PACAP was reversed by PACAP(6-38). PACAP-27 stimulated colony formation in NCI-H838 cells, whereas the PACAP antagonist PACAP(6-38) reduced colony formation in the absence or presence of exogenous PACAP-27. In nude mice bearing NCI-H838 xenografts, PACAP(6-38) slowed tumor growth significantly. These data suggest that biologically active type 1 PACAP receptors are present on human non-small cell lung cancer cells, which exhibit dual signal transduction pathways and regulate cell proliferation.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/patología , Receptores de la Hormona Hipofisaria/fisiología , Animales , Antineoplásicos/farmacología , Ácido Araquidónico/metabolismo , Sitios de Unión , Northern Blotting , Calcio/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , División Celular/fisiología , AMP Cíclico/metabolismo , Femenino , Humanos , Líquido Intracelular/metabolismo , Radioisótopos de Yodo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Trasplante de Neoplasias , Neuropéptidos/metabolismo , Neuropéptidos/farmacología , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa , Receptores del Polipéptido Activador de la Adenilato-Ciclasa Hipofisaria , Receptores del Polipéptido Activador de la Adenilato-Ciclasa Hipofisaria , Receptores de la Hormona Hipofisaria/metabolismo , Sensibilidad y Especificidad , Trasplante Heterólogo , Células Tumorales Cultivadas
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