279 results on '"M. Bajo"'
Search Results
102. La corteza auditiva en el procesamiento de la información espacial
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F Rodriguez-Nodal and V M Bajo-Lorenzana
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Sound localization ,Inferior colliculus ,Cognitive neuroscience of music ,General Medicine ,Biology ,Monaural ,Auditory cortex ,medicine.anatomical_structure ,Cortex (anatomy) ,medicine ,Auditory imagery ,Neurology (clinical) ,Neuroscience ,Binaural recording - Abstract
Sound localization is a computational process accomplished along the auditory pathway. Once the acoustic information received at each ear is analyzed independently (monaural cues) and comparatively (binaural cues), those cues are integrated to generate a coherent spatial percept. Using adult ferrets trained by positive conditioning in a spatial task, we aimed to study the role of the auditory cortex in the ability to localize sounds under both normal hearing and monaurally occluded conditions, the latter of which requires a reinterpretation of the values of the localization cues. Sound localization deficits were found after lesion or inactivation of the different auditory cortical regions, thereby indicating their participation in spatial processing. The differential impairments found in the approach-to-target and in the head movement responses reveal the complex relationship between cortex and midbrain which are putatively responsible for the voluntary and reflexive aspects of localization behaviour respectively. Furthermore, every auditory cortical region contributes to the adaptation process that follows monaural occlusion, indicating the key role that the auditory cortex plays in experience-dependent plasticity. Also, the selective lesion of the descending projections from the auditory cortex to the inferior colliculus by chromophore-targeted laser photolysis has revealed the essential function that descending pathways play in learning-induced localization plasticity. © Revista de Neurología.
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- 2012
103. Un sistema previsionale di storm surge nel Mar Mediterraneo
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C.Ferrarin, G.Umgiesser, A.Cucco, A. Roland, M. Bajo, S. Davolio, A. Buzzi, P. Malguzzi, O. Drofa, M. fantini, and C. Rendina
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- 2012
104. VIP receptor/effector system in liver membranes from cholestatic rats
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Eduardo Arilla, Juan-Carlos Prieto, Ana M. Bajo, Luis G. Guijarro, and Nieves Rodríguez-Henche
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Male ,medicine.medical_specialty ,Physiology ,Vasoactive intestinal peptide ,Biology ,medicine.disease_cause ,Biochemistry ,Adenylyl cyclase ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,Endocrinology ,Cholestasis ,GTP-Binding Proteins ,Internal medicine ,medicine ,Animals ,Rats, Wistar ,G alpha subunit ,Common Bile Duct ,Membranes ,Forskolin ,Neuropeptides ,ADCY9 ,Cholera toxin ,Cholestasis, Extrahepatic ,Glucagon ,medicine.disease ,Liver regeneration ,Liver Regeneration ,Rats ,Cross-Linking Reagents ,chemistry ,Receptors, Vasoactive Intestinal Peptide ,hormones, hormone substitutes, and hormone antagonists ,Adenylyl Cyclases ,Signal Transduction ,Vasoactive Intestinal Peptide - Abstract
A reduced efficacy of VIP (43% of the control) without modification in its potency (ED50 = 2.2 nM) was observed in regenerating rat liver after cholestasis (bile duct ligation). The same occurred with glucagon-stimulated adenylyl cyclase activity because the efficacy of this VIP-related peptide was also reduced (53% of the control) without changes in its potency in this experimental model. The equilibrium binding data revealed no changes in either the affinity or the VIP binding capacity of liver membranes during cholestasis. Cross-linking experiments gave the same apparent molecular mass for the liver VIP-receptor complex (52 kDa) in control and cholestatic rats. The coupling between the VIP receptor and the Gs-protein was also unaffected because the sensitivity of VIP binding to GTP did not change after bile duct ligation. However, liver membranes from cholestatic rats showed a low extent of both ADP-ribosylation of the Gs-protein alpha subunit (as assessed with cholera toxin) and adenylyl cyclase stimulation by a direct effector such as forskolin. Thus, VIP-stimulated adenylyl cyclase activity is decreased in regenerating liver after cholestasis due probably to an impairment in the interaction between Gs-protein and adenylyl cyclase as well as a defect in the enzyme itself.
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- 1994
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105. La modellistica operazionale in ambiente marino costiero 'downscaling' e 'upscaling' per mezzo di modelli a griglia non strutturata
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Umgiesser G., C. Ferrarin, A. Cucco, M. Bajo, D. Bellafiore, S. Davolio, A. Buzzi, P. Malguzzi, A. Pedroncini, and J.T. Sorensen
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- 2011
106. Neuronal morphology and efferent projections of the dorsal nucleus of the lateral lemniscus in the rat
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Victoria M. Bajo, Miguel A. Merchán, Dolores E. López, and Eric M. Rouiller
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Inferior colliculus ,General Neuroscience ,Superior colliculus ,Lateral lemniscus ,Anatomy ,Biology ,Medial geniculate body ,Retrograde tracing ,symbols.namesake ,nervous system ,Cytoarchitecture ,Superior olivary complex ,Nissl body ,symbols ,Neuroscience - Abstract
The dorsal nucleus of the lateral lemniscus (DLL) is the main source of inhibitory influence in the auditory brainstem of mammals. The cytoarchitecture and connectional properties of DLL were established in the cat in contrast to the rat. The goal of the present study was to establish to what extent the anatomical properties of the rat DLL compare to those of the cat, thus providing a basis of interpretation for future functional studies in the rat, an animal model used more and more in the auditory system. DLL of the rat contains four well-differentiated neuronal types, as seen in Nissl-stained material. Type I neurons are large and multipolar with abundant cytoplasm and darkly stained Nissl substance. Type II neurons are large, bipolar and darkly stained in Nissl material. Type III neurons are medium in size and their soma is round or ovoid. Type IV neurons are small and round with scant cytoplasm; they seem to be also the least common neuronal type of the DLL. After Phaseolus vulgaris-leucoagglutinin or biocytin injections in the DLL, fibers and terminals labeled by orthograde transport were observed in the corresponding region of the contralateral DLL and in the inferior colliculus, bilaterally. A few labeled fibers and terminal fields were seen in the deep layers of the superior colliculus bilaterally, as well as in the medial division of the medial geniculate body and, even more rostrally, in the posterior nucleus of the thalamus. Descending projections from DLL terminated in the periolivary regions of the ipsilateral superior olivary complex. Retrograde tracing based on injections of horseradish peroxidase in the various targets of the DLL confirmed the connections established with orthograde labeling.
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- 1993
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107. Regulation of HER expression and transactivation in human prostate cancer cells by a targeted cytotoxic bombesin analog (AN-215) and a bombesin antagonist (RC-3095)
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Laura Muñoz-Moreno, Andrew V. Schally, María J. Carmena, Sandra Sotomayor, Manuel Sánchez-Chapado, Ana M. Bajo, and Juan C. Prieto
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Male ,Transcriptional Activation ,Cancer Research ,medicine.medical_specialty ,Receptor, ErbB-2 ,medicine.medical_treatment ,Blotting, Western ,Antineoplastic Agents ,Apoptosis ,Targeted therapy ,Immunoenzyme Techniques ,chemistry.chemical_compound ,Prostate cancer ,Internal medicine ,LNCaP ,medicine ,Tumor Cells, Cultured ,Humans ,Epidermal growth factor receptor ,RNA, Messenger ,Bombesin Antagonist ,Cell Proliferation ,biology ,Reverse Transcriptase Polymerase Chain Reaction ,Bombesin ,Cancer ,Prostatic Neoplasms ,medicine.disease ,Peptide Fragments ,Gene Expression Regulation, Neoplastic ,Endocrinology ,Oncology ,chemistry ,Doxorubicin ,Cancer cell ,Cancer research ,biology.protein ,hormones, hormone substitutes, and hormone antagonists - Abstract
Bombesin (BN) and gastrin-releasing peptide (GRP) have been shown to stimulate the growth of human prostate cancer in vivo and in vitro by mechanisms initiated by binding of the peptide to BN/GRP receptor (GRPR). GRPR is overexpressed in a variety of human cancers, including human prostatic carcinoma. This led us to evaluate the effectiveness of blocking GRPR and of chemotherapy targeted to GRPR in androgen-dependent (LNCaP) and androgen-independent (PC-3) prostate cancer cells, which exhibit different features of disease progression. Thus, we used a cytotoxic BN/GRP analog, AN-215, consisting of 2-pyrrolinodoxorubicin (AN-201) linked to BN-like carrier peptide, and a BN/GRP receptor antagonist, RC-3095. Semiquantitative RT-PCR and Western blotting revealed that mRNA and protein levels for GRPR increased in prostate cancer cells as compared with nonneoplastic RWPE-1 cells. Immunofluorocytochemistry and Western blot assays revealed that AN-215 was the most effective analog decreasing both the expression of epidermal growth factor receptor family members and the activation of epidermal growth factor receptor and HER-2, which are associated to a poor prognosis. Furthermore, analogs targeted to BN/GRP receptors, AN-215 and RC-3095, blocked the effect of BN on cell growth in RWPE-1, LNCaP and PC-3 cells. These findings shed light on the mechanisms of action of these analogs and support the view that the use of AN-215 and RC-3095 for blocking BN/GRP receptors for targeted therapy may be of benefit for treatment of advanced prostate cancer.
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- 2010
108. The non-lemniscal auditory cortex in ferrets: convergence of corticotectal inputs in the superior colliculus
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Victoria M. Bajo, Andrew J. King, Jennifer K. Bizley, and Fernando R. Nodal
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Sound localization ,Posterior half ,Neuroscience (miscellaneous) ,Peripheral stimulus ,Biology ,Auditory cortex ,lcsh:RC321-571 ,lcsh:QM1-695 ,Cellular and Molecular Neuroscience ,Gyrus ,auditory cortical fields ,corticofugal input ,medicine ,Sound Localization ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,orientation behavior ,Original Research ,Superior colliculus ,multisensory integration ,Multisensory integration ,Anatomy ,lcsh:Human anatomy ,medicine.anatomical_structure ,orientation behaviour ,Neuroscience ,neural tracers - Abstract
Descending cortical inputs to the superior colliculus (SC) contribute to the unisensory response properties of the neurons found there and are critical for multisensory integration. However, little is known about the relative contribution of different auditory cortical areas to this projection or the distribution of their terminals in the SC. We characterized this projection in the ferret by injecting tracers in the SC and auditory cortex. Large pyramidal neurons were labeled in layer V of different parts of the ectosylvian gyrus after tracer injections in the SC. Those cells were most numerous in the anterior ectosylvian gyrus (AEG), and particularly in the anterior ventral field, which receives both auditory and visual inputs. Labeling was also found in the posterior ectosylvian gyrus (PEG), predominantly in the tonotopically organized posterior suprasylvian field. Profuse anterograde labeling was present in the SC following tracer injections at the site of acoustically responsive neurons in the AEG or PEG, with terminal fields being both more prominent and clustered for inputs originating from the AEG. Terminals from both cortical areas were located throughout the intermediate and deep layers, but were most concentrated in the posterior half of the SC, where peripheral stimulus locations are represented. No inputs were identified from primary auditory cortical areas, although some labeling was found in the surrounding sulci. Our findings suggest that higher level auditory cortical areas, including those involved in multisensory processing, may modulate SC function via their projections into its deeper layers. © 2010 Bajo, Nodal, Bizley and King.
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- 2010
109. Role of Primary Auditory Cortex in Acoustic Orientation and Approach-to-Target Responses
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Fernando R. Nodal, Victoria M. Bajo, and Andrew J. King
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Sound localization ,medicine.medical_specialty ,Sensory system ,Audiology ,Auditory cortex ,Horizontal plane ,Orienting response ,chemistry.chemical_compound ,medicine.anatomical_structure ,Gyrus ,Muscimol ,chemistry ,Cortex (anatomy) ,medicine ,Psychology - Abstract
The role of the primary auditory cortex in acoustic orientation and sound localization was explored by measuring the accuracy with which ferrets turned toward and approached the source of broadband sounds in the horizontal plane. In two animal groups trained by positive conditioning to perform this task, we either made small, bilateral aspiration lesions in the middle ectosylvian gyrus, where the primary auditory cortex is located, or implanted over it a polymer that released over a period of several weeks the GABAA agonist muscimol to silence the underlying cortex. Neither aspiration nor inactivation of the primary auditory cortex prevented the animals from orienting toward or approaching the source of the sound, but did produce a modest deficit in performance, as reflected by a reduction in accuracy in the localization of brief sounds (40-200 ms), especially for lateral locations. The accuracy of orienting responses was essentially unaltered, and only a small increase in variability for lateral sound locations was observed for short-duration stimuli. The close similarity in the behavioral responses observed after each manipulation suggests that these results reflect the true contribution of the primary auditory cortex to auditory localization. Given the modest nature of the observed deficits, our findings further suggest that additional areas within the auditory cortex must be also involved in spatial hearing.
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- 2010
110. Storm surge modelling in the Mediterranean Sea with focus on the Italian coast
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Ferrarin C., G. Umgiesser, A. Cucco, A. Roland, M. Bajo, S. Davolio, A. Buzzi, P. Malguzzi, O. Drofa, M. Fantini, and C. Rendina
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Computer Science::Performance ,Quantitative Biology::Tissues and Organs ,Physics::Space Physics ,Astrophysics::Earth and Planetary Astrophysics ,Physics::Geophysics - Abstract
This study examines the interactions between tide, wave and surge in determining the total water level in the Mediterranean Sea, by using a high resolution finite element tide-wave-surge model.
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- 2010
111. Lesions of the auditory cortex impair azimuthal sound localization and its recalibration in ferrets
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Victoria M. Bajo, Fernando R. Nodal, Jennifer K. Bizley, Andrew J. King, David R. Moore, and Oliver Kacelnik
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Sound localization ,Inferior colliculus ,Male ,Physiology ,Auditory area ,Auditory cortex ,Gyrus ,Neuroplasticity ,Neural Pathways ,medicine ,Animals ,Learning ,Sound Localization ,Auditory Cortex ,Neuronal Plasticity ,medicine.diagnostic_test ,General Neuroscience ,Superior colliculus ,Ferrets ,Magnetoencephalography ,Articles ,Electrophysiology ,medicine.anatomical_structure ,Acoustic Stimulation ,Data Interpretation, Statistical ,Head Movements ,Female ,Cues ,Psychology ,Neuroscience ,Psychomotor Performance - Abstract
The role of auditory cortex in sound localization and its recalibration by experience was explored by measuring the accuracy with which ferrets turned toward and approached the source of broadband sounds in the horizontal plane. In one group, large bilateral lesions were made of the middle ectosylvian gyrus, where the primary auditory cortical fields are located, and part of the anterior and/or posterior ectosylvian gyrus, which contain higher-level fields. In the second group, the lesions were intended to be confined to primary auditory cortex (A1). The ability of the animals to localize noise bursts of different duration and level was measured before and after the lesions were made. A1 lesions produced a modest disruption of approach-to-target responses to short-duration stimuli (
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- 2009
112. Multifunctional role of VIP in prostate cancer progression in a xenograft model: suppression by curcumin and COX-2 inhibitor NS-398
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Manuel Sánchez-Chapado, Juan C. Prieto, María J. Carmena, M. Isabel Arenas, Ana M. Bajo, Ana Valdehita, and Ana B. Fernández-Martínez
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Male ,medicine.medical_specialty ,Curcumin ,Physiology ,medicine.drug_class ,Vasoactive intestinal peptide ,Mice, Nude ,Antineoplastic Agents ,Biochemistry ,Polymerase Chain Reaction ,Tyrosine-kinase inhibitor ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,Prostate cancer ,Mice ,Endocrinology ,Prostate ,In vivo ,Internal medicine ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Nitrobenzenes ,Cell Proliferation ,Sulfonamides ,business.industry ,Cancer ,Prostatic Neoplasms ,medicine.disease ,Immunohistochemistry ,Xenograft Model Antitumor Assays ,Vascular endothelial growth factor ,medicine.anatomical_structure ,chemistry ,Cyclooxygenase 2 ,Cancer research ,Matrix Metalloproteinase 2 ,business ,Vasoactive Intestinal Peptide - Abstract
We used an in vivo model of human experimental prostate cancer in order to shed a new light on the effects of vasoactive intestinal peptide (VIP) on tumor growth as well as its pro-metastatic potential in this disease. We used nude mice subcutaneously injected with prostate cancer androgen-independent PC3 cells for 30 days. The regulatory role of VIP on cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF) expression as well as on matrix metalloproteinase-2 and 9 (MMP-2 and 9) activities was examined. A selective COX-2 inhibitor, NS-398, and curcumin were used to block VIP effects. Xenografts of VIP-treated PC3 prostate cancer cells in nude mice gave tumors that grew significantly faster than those in the untreated group. It is conceivably a result of both the trophic effect of VIP on prostate cancer cells and the proangiogenic action of the neuropeptide in the growing tumor. We show the overexpression at mRNA and/or protein levels of VIP, its main receptor VPAC 1 , the major angiogenic factor VEGF, and the pro-inflammatory enzyme COX-2 as well as the increased activity of MMP-2 and 9 in tumors derived from VIP-treated PC3 cells as compared with control group. The overexpression of the above biomarkers was suppressed in tumors derived from VIP-treated PC3 cells that had been previously incubated with curcumin or NS-398. Thus, the potential therapeutic role of curcumin and selective COX-2 inhibitors in combination with available VIP antagonists should be considered in prostate cancer therapy as supported by their inhibitory activities on tumor cell growth.
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- 2009
113. [Effectiveness evaluation of polypropylene mesh in the repair of urogenital prolapse in 106 patients]
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I, Zapardiel Gutiérrez, J, De la Fuente Valero, S, Iniesta Pérez, J, Botija Botija, T, Pérez Medina, and J M, Bajo Arenas
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Adult ,Aged, 80 and over ,Prolapse ,Humans ,Female ,Middle Aged ,Surgical Mesh ,Polypropylenes ,Female Urogenital Diseases ,Aged ,Retrospective Studies - Abstract
To evaluate the efficacy and security of polypropylene meshes in the repair of urogenital prolapse.Retrospective and non-randomized study in 106 patients which had different kinds of urogenital prolapse repaired using polypropylene meshes between April 2005 and January 2007. The follow-up was carried out by two visits to the hospital, 2 and 6 months after surgery. The variables analyzed were age, parity, menopause presence, kind of surgical technique, surgical time, time at hospital and complications. Afterwards, the information was analyzed descriptively.Average age was 64.4 years. The rate of multiparity and menopause women was 91.51% and 92.45% respectively. The most used surgical technique was the anterior mesh with tension-free band (34.90%), to repair the associated urinary incontinence. The rate of intraoperatory complications was 2.83%, immediate complications was 37.73% and late complications was 21.69%. The success rate after 6 months was 80-100% depending on the technique.There is a low rate of intraoperatory and 6 months after the repair in the reconstructive surgery of pelvic floor for the urogenital prolapses using polypropylene meshes, which makes this technique a secure and effective option for the treatment of this problem.
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- 2008
114. Vasoactive intestinal peptide (VIP) induces transactivation of EGFR and HER2 in human breast cancer cells
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María J. Carmena, Juan C. Prieto, Jozsef L. Varga, Ana Valdehita, Andrew V. Schally, and Ana M. Bajo
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Transcriptional Activation ,Vasoactive intestinal peptide ,Blotting, Western ,Molecular Sequence Data ,Breast Neoplasms ,Biochemistry ,Receptor tyrosine kinase ,Transactivation ,Endocrinology ,Cell Line, Tumor ,Humans ,RNA, Messenger ,Phosphorylation ,skin and connective tissue diseases ,Receptor ,Molecular Biology ,biology ,Base Sequence ,Chemistry ,Genes, erbB-2 ,Immunohistochemistry ,Protein Kinase A Inhibitor ,ErbB Receptors ,Gene Expression Regulation, Neoplastic ,biology.protein ,Cancer research ,Female ,Tyrosine kinase ,hormones, hormone substitutes, and hormone antagonists ,Platelet-derived growth factor receptor ,Vasoactive Intestinal Peptide - Abstract
We analyzed the cross-talk between receptors for vasoactive intestinal peptide (VIP) and the human epidermal growth factor family of tyrosine kinase receptors (HER) in oestrogen-dependent (T47D) and oestrogen-independent (MDA-MB-468) human breast cancer cells. VIP treatment slowly increased the expression levels of EGFR but it rapidly augmented phosphorylation of EGFR and HER2 in both cell lines. This pattern of HERs transactivation was blocked by the specific VIP antagonist JV-1-53, supporting the direct involvement of VIP receptors in formation of P-EGFR and P-HER2. VIP-induced transactivation was also abolished by H89 (protein kinase A inhibitor), PP2 (Src inhibitor) or TAPI-1 (inhibitor of matrix metalloproteases), following a differential pattern. These results shed a new light on the specific signalling pathways involved in EGFR/HER2 transactivation by VPAC receptors and suggest the potential usefulness of VIP receptor antagonists together with current antibodies against EGFR/HER2 and/or tyrosine kinase inhibitors for breast cancer therapy.
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- 2008
115. [The figure of the head of service (Chairman): what profile should have?]
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R, Vela Navarrete, J M, Bajo Arenas, J A, Martínez Piñeiro, V, Baena González, B, Miñana López, M, Unda Urzaiz, and C, Llorente Abarca
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Physician Executives ,Hospital Administration ,Spain - Abstract
Great social-health care changes in the short term have been predicted that will seriously affect the departmental structure and care hierarchy of future hospital, universitary, public or private. The Spanish Association of Urology (AEU) wondered whether in these circumstances, in which the welfare and economic management of the hospital so-called "industrial" will dominate over other traditional aspects of the scientific hierarchy, social welfare and teaching of head Urology of service, will change his image, goals, functions, and ultimately its authority. Likewise which must be the attributes of this new generation of department heads. To this end the AEU call a roundtable requesting opinions and comments which are reflected in the enclosed text.
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- 2008
116. [Effectiveness evaluation of tension-free vaginal tapes in the treatment of urinary incontinence and satisfaction of 241 patients]
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I, Zapardiel Gutiérrez, J, De la Fuente Valero, J, Botija Botija, T, Pérez Medina, M, Díez Fernández, and J M, Bajo Arenas
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Adult ,Aged, 80 and over ,Suburethral Slings ,Urinary Incontinence ,Patient Satisfaction ,Humans ,Female ,Middle Aged ,Prosthesis Design ,Aged ,Retrospective Studies - Abstract
Urinary incontinence is an extended problem between middle-aged women. There are several options for its correction with different effectiveness and complication rates. Our objective is to evaluate the effectiveness of tension-free vaginal transobturator tapes (TOT) in the repair of this incontinence. Also to evaluate the patients satisfaction rate with this kind of surgery.Retrospective study in 241 women with a surgical repair of their urinary incontinence with TOT. We analyzed the rates of effectiveness and satisfaction of the patients with the surgical repair after 2 and 6 months. The complication rate was also analyzed.Urinary continence rate 2 months after surgery was around 70% and the satisfaction one around 65%. After 6 months the rates were 70% and 70% respectively with a minimal variation depending on the associated surgery. The complication rate during surgery was 3.31% and the one after surgery was 26.55%, although most of them were minor complications.The use of TOT for the repair of urinary incontinence is an effective and safe option with a low complication rate. Moreover the rate of patients satisfaction is high.
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- 2008
117. Transactivation of HER2 by vasoactive intestinal peptide in experimental prostate cancer: Antagonistic action of an analog of growth-hormone-releasing hormone
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Jozsef L. Varga, Ana M. Bajo, Sandra Sotomayor, Juan C. Prieto, María J. Carmena, Andrew V. Schally, and Manuel Sánchez-Chapado
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Cancer Research ,medicine.medical_specialty ,biology ,Vasoactive intestinal peptide ,Tyrosine phosphorylation ,Receptor tyrosine kinase ,Transactivation ,chemistry.chemical_compound ,Endocrinology ,Oncology ,chemistry ,Internal medicine ,LNCaP ,Cancer research ,biology.protein ,medicine ,Receptor ,Autocrine signalling ,Tyrosine kinase ,hormones, hormone substitutes, and hormone antagonists - Abstract
Receptors for vasoactive intestinal peptide (VIP) and the human epidermal growth factor family of tyrosine kinase receptors (HER) are potent promoters of cell proliferation, survival, migration, adhesion and differentiation in prostate cancer cell lines. In this study, we analyzed the cross-talk between both classes of receptors through the regulation of HER2 transactivation and expression by VIP. Three growth-hormone-releasing hormone analogs endowed with antagonistic activity for VIP receptors (JV-1-51, -52, and -53) abrogated the autocrine/paracrine stimuli of VIP on androgen-independent PC3 cells in the absence or the presence of 10% fetal bovine serum. Semiquantitative and real-time quantitative RT-PCR together with Western blotting showed increased expression levels of both mRNA and proteins for HER2 and HER3 in PC3 and androgen-dependent LNCaP prostate cancer cells as compared to non-neoplastic RWPE-1 cells. VIP (100 nM) stimulated the expression levels of both HER2 and HER3 in PC3 cells in a time-dependent manner. Whereas these effects were relatively slow, VIP rapidly (0.5 min) increased HER2 tyrosine phosphorylation. This pattern of HER transactivation was blocked by H89, a protein kinase A (PKA) inhibitor, as well as by the specific VIP antagonist JV-1-53, indicating the involvement of VIP receptors and PKA activity in phosphorylated HER2 formation. These findings support the merit of further studies on the potential usefulness of VIP receptor antagonists and both HER2 antibodies and tyrosine kinase inhibitors for prostate cancer therapy.
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- 2007
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118. Transactivation of HER2 by vasoactive intestinal peptide in experimental prostate cancer: Antagonistic action of an analog of growth-hormone-releasing hormone
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Sandra, Sotomayor, María J, Carmena, Andrew V, Schally, Jozsef L, Varga, Manuel, Sánchez-Chapado, Juan C, Prieto, and Ana M, Bajo
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Male ,Receptor, ErbB-3 ,Receptor, ErbB-2 ,Cell Line, Tumor ,Humans ,Prostatic Neoplasms ,Receptors, Vasoactive Intestinal Peptide ,RNA, Messenger ,Phosphorylation ,Growth Hormone-Releasing Hormone ,Cyclic AMP-Dependent Protein Kinases ,Cell Proliferation ,Vasoactive Intestinal Peptide - Abstract
Receptors for vasoactive intestinal peptide (VIP) and the human epidermal growth factor family of tyrosine kinase receptors (HER) are potent promoters of cell proliferation, survival, migration, adhesion and differentiation in prostate cancer cell lines. In this study, we analyzed the cross-talk between both classes of receptors through the regulation of HER2 transactivation and expression by VIP. Three growth-hormone-releasing hormone analogs endowed with antagonistic activity for VIP receptors (JV-1-51, -52, and -53) abrogated the autocrine/paracrine stimuli of VIP on androgen-independent PC3 cells in the absence or the presence of 10% fetal bovine serum. Semiquantitative and real-time quantitative RT-PCR together with Western blotting showed increased expression levels of both mRNA and proteins for HER2 and HER3 in PC3 and androgen-dependent LNCaP prostate cancer cells as compared to non-neoplastic RWPE-1 cells. VIP (100 nM) stimulated the expression levels of both HER2 and HER3 in PC3 cells in a time-dependent manner. Whereas these effects were relatively slow, VIP rapidly (0.5 min) increased HER2 tyrosine phosphorylation. This pattern of HER transactivation was blocked by H89, a protein kinase A (PKA) inhibitor, as well as by the specific VIP antagonist JV-1-53, indicating the involvement of VIP receptors and PKA activity in phosphorylated HER2 formation. These findings support the merit of further studies on the potential usefulness of VIP receptor antagonists and both HER2 antibodies and tyrosine kinase inhibitors for prostate cancer therapy.
- Published
- 2007
119. Sound localization behavior in ferrets: comparison of acoustic orientation and approach-to-target responses
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Andrew J. King, Fernando R. Nodal, Victoria M. Bajo, Carl H. Parsons, and Jan W. H. Schnupp
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Sound localization ,medicine.medical_specialty ,Auditory Pathways ,Time Factors ,Sensory system ,Stimulus (physiology) ,Audiology ,Article ,Orienting response ,Orientation ,Psychophysics ,medicine ,Animals ,Second-order stimulus ,Sound Localization ,Communication ,Analysis of Variance ,Behavior, Animal ,business.industry ,General Neuroscience ,Ferrets ,Horizontal plane ,Acoustic Stimulation ,Head Movements ,Loudspeaker ,Psychology ,business - Abstract
Auditory localization experiments typically either require subjects to judge the location of a sound source from a discrete set of response alternatives or involve measurements of the accuracy of orienting responses made toward the source location. To compare the results obtained by both methods, we trained ferrets by positive conditioning to stand on a platform at the center of a circular arena prior to stimulus presentation and then approach the source of a broadband noise burst delivered from 1 of 12 loudspeakers arranged at 30 degrees intervals in the horizontal plane. Animals were rewarded for making a correct choice. We also obtained a non-categorized measure of localization accuracy by recording head-orienting movements made during the first second following stimulus onset. The accuracy of the approach-to-target responses declined as the stimulus duration was reduced, particularly for lateral and posterior locations, although responses to sounds presented in the frontal region of space and directly behind the animal remained quite accurate. Head movements had a latency of approximately 200 ms and varied systematically in amplitude with stimulus direction. However, the final head bearing progressively undershot the target with increasing eccentricity and rarely exceeded 60 degrees to each side of the midline. In contrast to the approach-to-target responses, the accuracy of the head orienting responses did not change much with stimulus duration, suggesting that the improvement in percent correct scores with longer stimuli was due, at least in part, to re-sampling of the acoustical stimulus after the initial head turn had been made. Nevertheless, for incorrect trials, head orienting responses were more closely correlated with the direction approached by the animals than with the actual target direction, implying that at least part of the neural circuitry for translating sensory spatial signals into motor commands is shared by these two behaviors.
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- 2007
120. Physiological and anatomical evidence for multisensory interactions in auditory cortex
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Andrew J. King, Fernando R. Nodal, Israel Nelken, Victoria M. Bajo, and Jennifer K. Bizley
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Sound localization ,Visual perception ,genetic structures ,Cognitive Neuroscience ,Auditory area ,Sensory system ,Stimulus (physiology) ,Auditory cortex ,Article ,Cellular and Molecular Neuroscience ,retrograde labeling ,Parietal Lobe ,medicine ,Animals ,Neurons, Afferent ,ferret ,sensory convergence ,Evoked Potentials ,information theory ,Visual Cortex ,Auditory Cortex ,cross-modal processing ,Superior colliculus ,Ferrets ,Electroencephalography ,Visual cortex ,medicine.anatomical_structure ,Acoustic Stimulation ,Data Interpretation, Statistical ,visual ,Visual Fields ,Psychology ,Neuroscience ,Algorithms ,Photic Stimulation - Abstract
Recent studies, conducted almost exclusively in primates, have shown that several cortical areas usually associated with modality-specific sensory processing are subject to influences from other senses. Here we demonstrate using single-unit recordings and estimates of mutual information that visual stimuli can influence the activity of units in the auditory cortex of anesthetized ferrets. In many cases, these units were also acoustically responsive and frequently transmitted more information in their spike discharge patterns in response to paired visual-auditory stimulation than when either modality was presented by itself. For each stimulus, this information was conveyed by a combination of spike count and spike timing. Even in primary auditory areas (primary auditory cortex [A1] and anterior auditory field [AAF]), approximately 15% of recorded units were found to have nonauditory input. This proportion increased in the higher level fields that lie ventral to A1/AAF and was highest in the anterior ventral field, where nearly 50% of the units were found to be responsive to visual stimuli only and a further quarter to both visual and auditory stimuli. Within each field, the pure-tone response properties of neurons sensitive to visual stimuli did not differ in any systematic way from those of visually unresponsive neurons. Neural tracer injections revealed direct inputs from visual cortex into auditory cortex, indicating a potential source of origin for the visual responses. Primary visual cortex projects sparsely to A1, whereas higher visual areas innervate auditory areas in a field-specific manner. These data indicate that multisensory convergence and integration are features common to all auditory cortical areas but are especially prevalent in higher areas.
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- 2007
121. Vasoactive intestinal peptide enhances growth and angiogenesis of human experimental prostate cancer in a xenograft model
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Celia Clemente, Juan C. Prieto, Beatriz Collado, Ana M. Bajo, and María J. Carmena
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Male ,Vascular Endothelial Growth Factor A ,medicine.medical_specialty ,Physiology ,Angiogenesis ,Vasoactive intestinal peptide ,Mice, Nude ,Antigens, CD34 ,Biochemistry ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,Prostate cancer ,Hemoglobins ,Mice ,Endocrinology ,In vivo ,Internal medicine ,Cell Line, Tumor ,LNCaP ,Medicine ,Animals ,Humans ,RNA, Messenger ,Matrigel ,Neovascularization, Pathologic ,business.industry ,Reverse Transcriptase Polymerase Chain Reaction ,Prostatic Neoplasms ,medicine.disease ,Immunohistochemistry ,Xenograft Model Antitumor Assays ,Tumor Burden ,Vascular endothelial growth factor ,Gene Expression Regulation, Neoplastic ,chemistry ,Cancer research ,Tumor promotion ,business ,Vasoactive Intestinal Peptide - Abstract
We show that vasoactive intestinal peptide (VIP) exerts trophic and proangiogenic activities in experimental prostate cancer in vivo . Nude mice were subcutaneously injected with Matrigel impregnated with LNCaP prostate cancer cells. Cell treatment with 100 nM VIP for 1 h before xenograft resulted in increased tumor growth after 8 and, more remarkably, 15 days of injection. The same occurred with the mRNA expression of the main angiogenic factor, vascular endothelial growth factor (VEGF), as shown by real-time RT-PCR quantification. The proangiogenic activity of VIP was further established by showing increases of hemoglobin levels, Masson trichromic staining, and immunohistochemical CD34 staining in tumors excised 15 days after subcutaneous injection of VIP-treated cells as compared to control conditions. All these parameters indicate that VIP increases vessel formation. This xenograft model is a useful tool to study in vivo the effects of VIP-related peptides in tumor growth and development of blood supply as well as their therapeutical potential in prostate cancer.
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- 2007
122. Mechanical qualification testing of SMOS payload module
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Miguel A. Gil, Jose M. Bajo, and Miguel A. Plaza
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Payload ,Computer science ,business.industry ,Qualification testing ,Aerospace engineering ,business - Published
- 2006
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123. Vasoactive intestinal peptide induces cyclooxygenase-2 expression through nuclear factor-kappaB in human prostate cell lines Differential time-dependent responses in cancer progression
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Ana B, Fernández-Martínez, Beatriz, Collado, Ana M, Bajo, Manuel, Sánchez-Chapado, Juan C, Prieto, and María J, Carmena
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Male ,Curcumin ,Time Factors ,NF-kappa B ,Membrane Proteins ,Prostatic Neoplasms ,Gene Expression Regulation, Enzymologic ,Gene Expression Regulation, Neoplastic ,Protein Transport ,Cyclooxygenase 2 ,Cell Line, Tumor ,Disease Progression ,Humans ,RNA, Messenger ,Vasoactive Intestinal Peptide - Abstract
The effect of vasoactive intestinal peptide (VIP) on cyclooxygenase-2 (COX-2) expression was analyzed in human prostate non-neoplastic (RWPE-1) as well as cancer androgen-dependent (LNCaP) and independent (PC3) cells. The three cell lines expressed VIP mRNA and VIP peptide, as measured by RT-PCR and immunochemistry, which supports an autocrine/paracrine action of VIP in the prostate gland. VIP levels were progressively higher from non-neoplastic to androgen-dependent and independent cells. Real-time RT-PCR and Western-blotting showed that VIP stimulated both COX-2 mRNA and protein expression in a faster manner as prostate cancer stage progressed (i.e. RWPE1LNCaPPC3 cells). Furthermore, VIP induced higher levels of COX-2 protein expression in cancer cells as compared with non-neoplastic cells. The anti-inflammatory agent curcumin blocked VIP-induced COX-2 expression in all cell lines studied supporting the involvement of nuclear factor-kappaB (NFkappaB) in such a response. In fact, VIP increased the translocation of the NFkappaB p50 subunit to the nucleus and the binding of the active form to its target gene promoter, as measured by Western-blotting and ELISA, respectively. VIP provoked faster responses according to the most aggressive status in cancer progression (androgen-independent situation). These results together with the existence of two NFkappaB sites in the COX-2 gene promoter together suggest that COX-2 may be a target for VIP in prostate cancer progression. On the other hand, VIP could be a proinflammatory cytokine acting through the NFkappaB/COX-2 system.
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- 2006
124. The ferret auditory cortex: descending projections to the inferior colliculus
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Andrew J. King, Jennifer K. Bizley, David R. Moore, Victoria M. Bajo, and Fernando R. Nodal
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Inferior colliculus ,Auditory Cortex ,Inferior Colliculi ,Auditory Pathways ,Cognitive Neuroscience ,Superior colliculus ,Ferrets ,Anatomy ,Biology ,Auditory cortex ,Periaqueductal gray ,Article ,Cellular and Molecular Neuroscience ,medicine.anatomical_structure ,Gyrus ,Receptive field ,Tegmentum ,medicine ,Animals ,Neuroscience - Abstract
Descending corticofugal projections are thought to play a critical role in shaping the responses of subcortical neurons. Here, we examine the origins and targets of ferret auditory corticocollicular projections. We show that the ectosylvian gyrus (EG), where the auditory cortex is located, can be subdivided into middle, anterior, and posterior regions according to the pattern of cytochrome oxidase staining and immunoreactivity for the neurofilament antibody SMI(32). Injection of retrograde tracers in the inferior colliculus (IC) labeled large layer V pyramidal cells throughout the EG and adjacent sulci. Each region of the EG has a different pattern of descending projections. Neurons in the primary auditory fields in the middle EG project to the lateral nucleus (LN) of the ipsilateral IC and bilaterally to the dorsal cortex and dorsal part of the central nucleus (CN). The projection to these dorsomedial regions of the IC is predominantly ipsilateral and topographically organized. The secondary cortical fields in the posterior EG target the same midbrain areas but exclude the CN of the IC. A smaller projection to the ipsilateral LN also arises from the anterior EG, which is the only region of auditory cortex to target tegmental areas surrounding the IC, including the superior colliculus, periaqueductal gray, intercol-licular tegmentum, and cuneiform nucleus. This pattern of cortico-collicular connectivity is consistent with regional differences in physiological properties and provides another basis for subdividing ferret auditory cortex into functionally distinct areas.
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- 2006
125. Can pleiomorphic psychotic symptoms with movement disorders mask wilson’s disease?
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J. Marques and M. Bajouco
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Wilson’s disease ,PSYCHOTIC DISORDERS ,First Episode Psychosis ,Psychiatry ,RC435-571 - Abstract
Introduction Wilson’s disease is a rare (1:30,000) autosomal recessive disorder of copper metabolism that is caused by mutations in the adenosine triphosphatase copper transporting beta (ATP7B) gene, located on chromosome 13. The reported percentage of patients with psychiatric symptoms as the presenting clinical feature is 10%-20%. Objectives To present and discuss a rare case admitted in the First Psychotic Episode Inpatient Unit (UIPEP) with pleiomorphic psychotic symptoms and low serum copper and ceruloplasmin and high 24h urine copper. Methods The data was collected through patient and family interviews, as well as from his medical record. We searched Pubmed using MeSH terms: psychotic disorders AND Hepatolenticular Degeneration. Results A twenty-two years old male, without known psychiatric history presented in the Emergency Department with a myriad of psychotic symptoms: motor stereotypes/mannerisms, paranoid delusions and auditory hallucinations. He was admitted in UIPEP, started low-dose antipsychotic medication with good response. As part of the implemented protocol, he did a battery of exams, including Brain CT-scan, EEG, ECG and blood and urine analysis, in which low serum copper and ceruloplasmin stood out, leveraging the suspicion of Wilson´s disease. Therefore, 24h urine copper was done, with 140 mcg/d (reference range < 40 mcg/d). Brain MRI was normal and no Kayser–Fleisher rings were seen by a consulting ophthalmologist. Conclusions Without proper treatment, Wilson’s disease is a progressive and fatal disease. Therefore, it’s of upmost importance to recognize the clinical signs that raise suspicion of this disorder, especially recent onset in young adult of miscellaneous psychotic symptoms with movement disorders. Disclosure No significant relationships.
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- 2022
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126. COVID-19 Pandemic: Another Source of Stress for Medical Students
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A.T. Pereira, C. Cabacos, A. Araújo, M.J. Soares, M.J. Brito, F. Carvalho, D. Mota, M. Bajouco, N. Madeira, M. Carneiro, and A. Macedo
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stress sources ,Covid-19 pandemic ,depression anxiety and stress scale ,medical students ,Psychiatry ,RC435-571 - Abstract
Introduction The COVID-19 pandemic has completely changed the experience of higher education with potentially negative consequences for students’ wellbeing. Objectives To compare medicine/dentistry students’ depression/anxiety/stress levels before versus during the pandemic and to analyse the role of COVID-19-related stressors in their psychological distress. Methods Students from the Faculty of Medicine University of Coimbra answered socio-demographic and personality questionnaires and the Depression, Anxiety and Stress Scale/DASS before (academic years 2016-2017-2018-2019 - SAMPLE1; n=1000) and during (September-December 2020 and January-March 2021 - SAMPLE2; n=650) the COVID-19 pandemic. Mean age (21.12±3.75), personality traits scores, and gender proportions (»75% girls) did not significantly differ between samples. SAMPLE2 also filled in the Fear of COVID-19 Scale and a new version of the Inventory of Sources of Stress During Medical Education/ISSDME, containing a COVID-19 -related dimension (restrictions on training and on socializing with friends/colleagues). Results SAMPLE2 presented significantly higher mean scores of depression (3.89±3.55vs.3.33±3.34), anxiety (3.27±4.08vs.2.86±3.29), stress (7.07±5.72vs.6.18±4.59) and total DASS (12.28±10.55vs.13.65±11.13) than SAMPLE1 (all p
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- 2022
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127. Descending projections from the auditory cortex to the inferior colliculus in the gerbil, Meriones unguiculatus
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David R. Moore and Victoria M. Bajo
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Inferior colliculus ,Auditory Pathways ,Auditory area ,Presynaptic Terminals ,Biotin ,Biology ,Auditory cortex ,Periaqueductal gray ,Functional Laterality ,Electron Transport Complex IV ,Midbrain ,Neurofilament Proteins ,Apical dendrite ,Cortex (anatomy) ,medicine ,Animals ,Periaqueductal Gray ,Fluorescent Dyes ,Auditory Cortex ,Brain Mapping ,Pyramidal Cells ,General Neuroscience ,Dextrans ,Dendrites ,Anatomy ,Immunohistochemistry ,Axons ,Inferior Colliculi ,medicine.anatomical_structure ,Auditory Perception ,Tonotopy ,Gerbillinae ,Neuroscience - Abstract
Corticofugal projections to the auditory midbrain, the inferior colliculus (IC), influence the way in which specific sets of IC neurons process acoustic signals. We used retrograde tracer (Fluorogold, Fluororuby, microbeads) injections in the IC to study the morphology and location of cortico-collicular projecting neurons and anterograde tracer (dextran biotin) injections in auditory cortical fields to describe the distribution of terminals in the IC. Nissl staining, cytochrome oxidase activity, and neurofilament SMI32 immunostaining were used to delimit the different auditory areas. We defined a primary or "core" auditory cortex and a secondary "caudal" auditory area containing layer V pyramidal neurons that project to the IC. These projections target the central nucleus of the IC (CNIC) ipsilaterally and the IC cortices bilaterally, with the ipsilateral component predominant. Other secondary auditory areas, dorsal and ventral to the core, do not directly participate in this projection. The ventral secondary cortex targets midbrain periaqueductal gray. The projection from the core cortex originates from two classes of layer V pyramidal cells. Cells presenting a tufted apical dendrite in layer I have dense terminal fields in the IC cortices. Pyramids lacking layer I dendritic tufts target the CNIC in a less dense but tonotopic manner. The caudal cortex projection originates from smaller layer V pyramids and targets the IC cortices with dense terminal fields. Descending auditory inputs from the core and caudal areas converge in the dorsal and external cortices of the IC. Descending connections to the gerbil IC form a segregated system in which multiple descending channels originating from different neuronal subpopulations may modulate specific aspects of ascending auditory information.
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- 2005
128. Features of scatterometer wind observations in the Adriatic Sea
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S. Zecchetto, F. De Biasio, and M. Bajo
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marine atmospheric boundary layer (MABL) ,Adriatic Sea ,sea surface wind ,stability ,scatterometry - Abstract
The Mediterranean Sea is a basin where the wind circulation at sub-synoptic scales may be strongly influenced by the coastal orography and by the presence of many islands. As a consequence, meteorological phenomena at spatial scales of up to a few kilometres are very common. They are important for the whole dynamic of the atmosphere but their simulation by atmospheric models is difficult. In the Adriatic Sea, for instance, the channelling effects due to the presence of the Apennines and Balkan Mountains chains occurs under the influence of both north-easterly and south-easterly winds. In this context, satellite wind observations from microwave scatterometers are of primary importance. With a spatial resolution of c. 25 km by 25 km, they provide a thorough description of many meso-scale phenomena, such as frontal systems and orographic winds, as well as of the structure of the regional wind systems (Guymer and Zecchetto, 1993; Zecchetto and Cappa, 2001; Zecchetto et al., 2002). This chapter aims to illustrate the potentialities offered by scatterometer wind observations in the characterization of wind fields in the Adriatic Sea, and to discuss their possible use as forcing fields in storm surge hindcasting. The second describes the main characteristics of the scatterometer wind observations, their present and future availability, and their temporal sampling of basins like the Adriatic Sea. In the third, two case studies are presented, one of bora and one of scirocco, the two most important winds in the Adriatic Sea. How these wind types are described by the scatterometer is compared with how they are described by the analysis wind fields. The fourth discusses the possible advantages in considering the scatterometer winds as meteorological forcing for storm surge hindcasting, while the last section is devoted to conclusions and recommendations for future work.
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- 2005
129. Solubilization of adenylyl cyclase from human myometrium in a alphas-coupled form
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Ana M. Bajo, Pilar Martinez, Pedro L. Valenzuela, Juan C. Prieto, and Luis G. Guijarro
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Gs alpha subunit ,G protein ,Octoxynol ,Protein subunit ,Size-exclusion chromatography ,Detergents ,Biophysics ,Polidocanol ,Biochemistry ,Polyethylene Glycols ,Adenylyl cyclase ,Sepharose ,chemistry.chemical_compound ,Chaps ,GTP-Binding Protein alpha Subunits, Gs ,Humans ,Molecular Biology ,Forskolin ,Chromatography ,Chemistry ,Cholic Acids ,Cell Biology ,Chromatography, Agarose ,Solubility ,Myometrium ,Female ,Adenylyl Cyclases - Abstract
Adenylyl cyclase (AC) was extracted from human myometrium with either non-ionic (Lubrol-PX or Triton X-100) or zwitterionic (3-[3-cholamidopropyl)dimethylammonio]-1-propanesulfonate, CHAPS) detergents. The soluble enzyme was stimulated by forskolin, a hydrophobic activator, in the presence of Mg2+ indicating that the catalytic subunit had not been damaged after solubilization. The enzyme was also activated by 5′-guanylyl imidodiphosphate (Gpp(NH)p) showing that the catalytic unit was not separated from stimulatory guanine nucleotide binding protein (Gs) during the extraction. Both activators showed different effects on the stimulatory efficacy and potency of AC activity solobulized with detergents. Gel filtration of Lubrol-PX and CHAPS extracts over a Sepharose CL-2B column partially resolved AC and its complexes. The chromatographic profile for Lubrolsolubilized AC presented a main peak of about 200 kDa whereas CHAPS-solubilized AC showed a dominant peak of about 1100 kDa. The heterodisperse peaks obtained revealed that the catalytic AC subunit was not separated from Gs proteins after gel filtration, and that AC could be associated with other cellular proteins. When Lubrol extract was submitted to anionic-exchange chromatography, the enzyme was purified about 7.5 fold (enzymatic activity of 48.1 pmol/min/mg of protein). The catalytic subunit was co-eluted with both AC-activating proteins Gαs large (52.2 kDa) and Gαs small (48.7 kDa). This is the first demonstration of the stable physical association of AC with both αs subunits of G proteins in human myometrium.
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- 2004
130. Targeted doxorubicin-containing luteinizing hormone-releasing hormone analogue AN-152 inhibits the growth of doxorubicin-resistant MX-1 human breast cancers
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Ana M, Bajo, Andrew V, Schally, Gabor, Halmos, and Attila, Nagy
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Antibiotics, Antineoplastic ,Time Factors ,Receptor, ErbB-3 ,Receptor, ErbB-2 ,Reverse Transcriptase Polymerase Chain Reaction ,Blotting, Western ,Mice, Nude ,Breast Neoplasms ,Mammary Neoplasms, Animal ,Luteinizing Hormone ,Protein-Tyrosine Kinases ,Gonadotropin-Releasing Hormone ,Mice ,Doxorubicin ,Drug Resistance, Neoplasm ,Cell Line, Tumor ,Animals ,Humans ,Female ,RNA, Messenger ,Neoplasm Transplantation ,Protein Binding - Abstract
The receptors for luteinizing hormone-releasing hormone receptor (LHRH-R) are found in50% of human breast cancers. Doxorubicin (DOX) was linked to [D-Lys(6)]LHRH to form a cytotoxic conjugate, AN-152, which can be targeted to tumor cells expressing LHRH-R. We evaluated the effects of AN-152 on the estrogen-independent, DOX-resistant human mammary carcinoma line MX-1, xenografted into nude mice.Nude mice bearing MX-1 tumors were administered five i.v. injections of AN-152 or DOX at doses equivalent to 3 mg/kg DOX. Tumor growth was followed, and changes in the expression of LHRH-R on tumors were evaluated by radioreceptor assays, reverse transcription-PCR, and Western blotting. The effects of AN-152 on the expression of human epidermal growth factor receptor (HER)-2 were investigated. Because LHRH-R are coupled to various G proteins, which are involved in mitogenic signaling, we determined the outcome of treatment with AN-152 on the levels of mRNA for different G proteins.Treatment with AN-152 significantly (P0.05) decreased the final tumor volume to 978.56 +/- 176.85 mm(3), compared with the control tumors, which measured 2837.38 +/- 515.38 mm(3). Tumor doubling time was likewise significantly (P0.05) extended by AN-152 to 12.01 +/- 1.99 days from 6.45 +/- 0.36 days for the controls. Therapy with AN-152, but not with DOX, resulted in a significant decrease of LHRH-R levels on MX-1 tumors. The expression of mRNAs for HER-2, HER-3, Galpha(i2), and Galpha(11) and the levels of HER-2 and HER-3 proteins were also significantly reduced by AN-152.Cytotoxic LHRH analogue AN-152 could be considered for targeted chemotherapy of DOX-resistant breast cancers expressing LHRH-R.
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- 2003
131. Effective treatment of H838 human non-small cell lung carcinoma with a targeted cytotoxic somatostatin analog, AN-238
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Zoltan Szereday, Gabor Halmos, Ana M. Bajo, Karoly Szepeshazi, Attila Nagy, Andrew V. Schally, and Francine Hebert
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Cancer Research ,medicine.medical_specialty ,Lung Neoplasms ,Transplantation, Heterologous ,Mice, Nude ,Peptide hormone ,Biology ,Leukocyte Count ,Mice ,Carcinoma, Non-Small-Cell Lung ,Internal medicine ,Tumor Cells, Cultured ,medicine ,Animals ,Humans ,Doubling time ,Cytotoxic T cell ,Pyrroles ,Cytotoxins ,Somatostatin receptor ,Gyógyszerészeti tudományok ,Orvostudományok ,Ligand (biochemistry) ,Molecular biology ,Transplantation ,Kinetics ,Endocrinology ,Somatostatin ,Oncology ,Doxorubicin ,Apoptosis ,Cell Division - Abstract
The accumulation of radioactive somatostatin analog [111In]pentetreotide in non-small cell lung cancer (non-SCLC) during scintigraphy of patients provides a rationale for investigating the efficacy of somatostatin receptor-based chemotherapy in non-SCLC. Consequently, in this study, we evaluated the antitumor effects of cytotoxic somatostatin analog AN-238 on H838 human non-SCLC xenografted into nude mice in comparison with its cytotoxic radical, 2-pyrrolinodoxorubicin (AN-201). The expression of messenger RNA (mRNA) for human somatostatin receptor subtypes 2 (hsst2) and 5 (hsst5) in H838 cells, and tumors was also investigated using reverse-transcription polymerase chain reaction (RT-PCR). Somatostatin receptors on H838 tumors were characterized by ligand competition assay using radiolabeled somatostatin analog, RC-160. Three i.v. injections of AN-238 at 150 nmol/kg, given on days 1, 7 and 21, resulted in a significant (p
- Published
- 2003
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132. Growth hormone-releasing hormone (GHRH) antagonists inhibit the proliferation of androgen-dependent and -independent prostate cancers
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Ana M. Bajo, Rebeca Busto, Andrew V. Schally, Jozsef L. Varga, and Markus Letsch
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Male ,Vascular Endothelial Growth Factor A ,medicine.medical_specialty ,Time Factors ,medicine.drug_class ,Blotting, Western ,Mice, Nude ,Endothelial Growth Factors ,Biology ,urologic and male genital diseases ,Growth Hormone-Releasing Hormone ,Prostate cancer ,chemistry.chemical_compound ,Mice ,Prostate ,Insulin-Like Growth Factor II ,Internal medicine ,LNCaP ,medicine ,Tumor Cells, Cultured ,Animals ,Humans ,RNA, Messenger ,Insulin-Like Growth Factor I ,Multidisciplinary ,Reverse Transcriptase Polymerase Chain Reaction ,Prostatic Neoplasms ,Biological Sciences ,Prostate-Specific Antigen ,medicine.disease ,Growth hormone–releasing hormone ,Androgen ,Vascular endothelial growth factor ,Vascular endothelial growth factor A ,Endocrinology ,medicine.anatomical_structure ,chemistry ,Cell Division ,Neoplasm Transplantation ,Hormone - Abstract
The antiproliferative effects of an antagonist of growth hormone-releasing hormone (GHRH) JV-1-38 were evaluated in nude mice bearing s.c. xenografts of LNCaP and MDA-PCa-2b human androgen-sensitive and DU-145 androgen-independent prostate cancers. In the androgen-sensitive models, JV-1-38 greatly potentiated the antitumor effect of androgen deprivation induced by surgical castration, but was ineffective when given alone. Thus, in castrated animals bearing MDA-PCa-2b cancers, the administration of JV-1-38 for 35 days virtually arrested tumor growth (94% inhibition vs. intact control, P < 0.01; and 75% vs. castrated control, P < 0.05). The growth of LNCaP tumors was also powerfully suppressed by JV-1-38 combined with castration (83% inhibition vs. intact control, P < 0.01; and 68% vs. castrated control, P < 0.05). However, in androgen-independent DU-145 cancers, JV-1-38 alone could inhibit tumor growth by 57% ( P < 0.05) after 45 days. In animals bearing MDA-PCa-2b and LNCaP tumors, the reduction in serum prostate-specific antigen levels, after therapy with JV-1-38, paralleled the decrease in tumor volume. Inhibition of MDA-PCa-2b and DU-145 cancers was associated with the reduction in the expression of mRNA and protein levels of vascular endothelial growth factor. The mRNA expression for GHRH receptor splice variants was found in all these models of prostate cancer. Our results demonstrate that GHRH antagonists inhibit androgen-independent prostate cancers and, after combination with androgen deprivation, also androgen-sensitive tumors. Thus, the therapy with GHRH antagonist could be considered for the management of both androgen-dependent or -independent prostate cancers.
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- 2003
133. Satellite wind observations as possible meteorological forcing for storm surge models
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Zecchetto and F. De Biasio e M. Bajo
- Published
- 2003
134. Effective treatment of experimental ES-2 human ovarian cancers with a cytotoxic analog of luteinizing hormone-releasing hormone AN-207
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Attila Nagy, Jose M. Arencibia, Ioulia Chatzistamou, Magdalena Krupa, Andrew V. Schally, and Ana M. Bajo
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endocrine system ,Cancer Research ,medicine.medical_specialty ,Receptor, ErbB-2 ,medicine.medical_treatment ,Drug Evaluation, Preclinical ,Mice, Nude ,Antineoplastic Agents ,Gonadotropin-Releasing Hormone ,Mice ,In vivo ,Internal medicine ,medicine ,Tumor Cells, Cultured ,Cytotoxic T cell ,Animals ,Humans ,Pharmacology (medical) ,Pyrroles ,RNA, Messenger ,Receptor ,Pharmacology ,Ovarian Neoplasms ,Chemotherapy ,Messenger RNA ,Chemistry ,Reverse Transcriptase Polymerase Chain Reaction ,medicine.disease ,ErbB Receptors ,Endocrinology ,Treatment Outcome ,Oncology ,Doxorubicin ,Female ,Luteinizing hormone ,Ovarian cancer ,hormones, hormone substitutes, and hormone antagonists ,Neoplasm Transplantation ,Receptors, LHRH ,Hormone - Abstract
The receptors for luteinizing hormone-releasing hormone (LHRH) are found In 80% of human ovarian carcinomas. These receptors can be used for targeted chemotherapy with cytotoxic analogs of LHRH, such as AN-207, consistingof 2-pyrrolinodoxorubicin (AN-201) linked to [D-Lys 6 ]LHRH. We investigated the effects of AN-207 and AN-201 on the In vivo growth of LHRH receptor-positive ES-2 human ovarian cancers. The effects of the treatment on mRNA and protein levels of human epidermal growth factor (EGF) receptors (EGFR and HER-2) in ovarian tumors were determined by RT-PCR and immunoblotting. In Experiment 1, nude mice bearing ES-2 ovarian tumors were injected i.v. with 250 nmol/kg doses of AN-207, AN-201, the carrier [D-Lys 6 ]LHRH, an unconjugated mixture of AN-201 and [D-Lys 6 ]LHRH or vehicle. AN-207 caused a significant (p
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- 2002
135. Doppler study of arterial and venous intraovarian blood flow in stimulated cycles
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L T, Mercé, S, Bau, and J M, Bajo
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Adult ,Ovulation ,Ovary ,Arteries ,Luteal Phase ,Veins ,Follicular Phase ,Ovarian Follicle ,Ovulation Induction ,Ultrasonography, Doppler, Pulsed ,Infertility ,Pulsatile Flow ,Humans ,Female ,Vascular Resistance ,Prospective Studies ,Follicle Stimulating Hormone ,Ultrasonography, Doppler, Color ,Blood Flow Velocity ,Menstrual Cycle ,Progesterone - Abstract
To evaluate arterial and venous intraovarian blood flow in follicle stimulating hormone-stimulated cycles.This was a prospective study of 76 follicle stimulating hormone-stimulated cycles carried out in 39 infertile patients who were included in a timed intercourse or intrauterine insemination program in a referral center for assisted reproduction. Transvaginal color and pulsed Doppler measurements of the follicular and luteal phase resistance index, pulsatility index, peak systolic velocity and maximum venous velocity were made and serum progesterone levels during the mid-luteal phase were recorded. Velocimetric parameters were established and then used to classify ovarian function as having a normal ovulatory cycle, or a cycle in which there was either luteal phase deficiency or a luteinized unruptured follicle.In 52 normal ovulatory cycles, the luteal phase peak systolic and maximum venous velocities were significantly higher and resistance and pulsatility indices were significantly lower than those found in the follicular phase. In 15 women with luteal phase deficiency we did not find any differences in arterial velocimetric parameters when compared with normal ovulatory cycles. However, luteal phase maximum venous velocities were lower in the luteal phase deficiency cycles and there was a significant correlation between luteal phase maximum venous velocity and serum progesterone levels (r = 0.36). Luteinized unruptured follicle cycles (n = 9) did not show significant changes during the ovarian cycle and no 'luteal conversion' of the Doppler signal was identified.Follicle stimulating hormone-stimulated cycles in infertile patients can have a high percentage of abnormal functional responses that can be diagnosed only by sonographic assessment, Doppler and the appropriate hormonal follow-up. Arterial and venous intraovarian blood flow remain unaltered during luteinized unruptured follicle cycles and serum progesterone levels correlated with luteal phase maximum venous velocity, which makes Doppler a potentially useful non-invasive test to assess ovulation and luteal function.
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- 2002
136. Effective treatment of experimental U-87MG human glioblastoma in nude mice with a targeted cytotoxic bombesin analogue, AN-215
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Kate Groot, A Nagy, Zoltan Szereday, Andrew V. Schally, Karoly Szepeshazi, Ana M. Bajo, Gabor Halmos, and Artur Plonowski
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Cancer Research ,medicine.medical_specialty ,Mice, Nude ,Biology ,doxorubicin ,chemistry.chemical_compound ,Mice ,tumour targeting ,Gastrin-releasing peptide ,Internal medicine ,medicine ,Tumor Cells, Cultured ,Doubling time ,Cytotoxic T cell ,Animals ,Humans ,Doxorubicin ,Experimental Therapeutics ,RNA, Messenger ,Receptor ,Bombesin Antagonist ,bombesin receptor ,Reverse Transcriptase Polymerase Chain Reaction ,Bombesin ,RT–PCR ,Bombesin receptor ,Receptors, Bombesin ,Endocrinology ,Oncology ,chemistry ,Cancer research ,Glioblastoma ,Cell Division ,Neoplasm Transplantation ,medicine.drug - Abstract
Some brain tumours, such as glioblastomas express high levels of receptors for bombesin/gastrin releasing peptide. We investigated whether bombesin/gastrin releasing peptide receptors found in glioblastoma cell lines can be utilised for targeting of a cytotoxic bombesin analogue, AN-215 consisting of a potent derivative of doxorubicin, 2-pyrrolino-doxorubicin (AN-201) linked to a bombesin-like peptide carrier. This study reports the effect of AN-215 on the growth of U-87MG human glioblastomas xenografted into nude mice. High affinity binding of AN-215 to U-87MG tumours was characterised by an IC50 value of 4.0±0.1 nM, as determined by radioreceptor assays. mRNA analyses revealed the presence of mRNA for BN receptor subtypes 1 and 2. Treatment with AN-215 significantly (P
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- 2001
137. Targeting of doxorubicin to ES-2 human ovarian cancers in nude mice by linking to an analog of luteinizing hormone-releasing hormone improves its effectiveness
- Author
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Ana M. Bajo, Andrew V. Schally, Jose M. Arencibia, Magdalena Krupa, Artur Plonowski, Karoly Szepeshazi, and Attila Nagy
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Vascular Endothelial Growth Factor A ,endocrine system ,Cancer Research ,medicine.medical_specialty ,Proto-Oncogene Proteins c-jun ,Receptor, ErbB-2 ,Mice, Nude ,Antineoplastic Agents ,Ovary ,Endothelial Growth Factors ,Biology ,Peptide hormone ,Gonadotropin-Releasing Hormone ,Mice ,chemistry.chemical_compound ,Internal medicine ,Tumor Cells, Cultured ,medicine ,Animals ,Humans ,Doxorubicin ,RNA, Messenger ,Epidermal growth factor receptor ,Receptor ,DNA Primers ,Ovarian Neoplasms ,Lymphokines ,Oncogene ,Reverse Transcriptase Polymerase Chain Reaction ,Vascular Endothelial Growth Factors ,Middle Aged ,medicine.disease ,ErbB Receptors ,Vascular endothelial growth factor ,Endocrinology ,medicine.anatomical_structure ,Oncology ,chemistry ,Cancer research ,biology.protein ,Female ,Ovarian cancer ,Proto-Oncogene Proteins c-fos ,medicine.drug - Abstract
Receptors for luteinizing hormone-releasing hormone (LHRH), expressed by ovarian cancers, can be used for targeting chemotherapeutic compounds more selectively to these tumors. We investigated the effects of cytotoxic LHRH analog AN-152, consisting of doxorubicin (DOX)-14-O-hemiglutarate linked to the epsilon-amino group of [D-Lys6]LHRH, on the growth of LHRH receptor-positive ES-2 human ovarian cancer line xenografted into nude mice. A single injection of AN-152, at a dose of 345 nmol/20 g body weight, caused a 34.5% reduction (P
- Published
- 2001
- Full Text
- View/download PDF
138. Impairment of adenylate cyclase activity and G-proteins in human uterine leiomyoma
- Author
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Juan-Carlos Prieto, Ana M. Bajo, J. Cortés, R.L. Hrı̈stov, Luis G. Guijarro, I. Carrero, Pedro L. Valenzuela, and Pilar Martinez
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Adult ,medicine.medical_specialty ,G protein ,Biopsy ,Immunoblotting ,Adenylate kinase ,Biology ,Hysterectomy ,Cyclase ,chemistry.chemical_compound ,GTP-Binding Proteins ,Internal medicine ,medicine ,Cyclic AMP ,Humans ,Uterine leiomyoma ,Forskolin ,Dose-Response Relationship, Drug ,Leiomyoma ,Colforsin ,Myometrium ,Cell Biology ,General Medicine ,Fibroblasts ,Middle Aged ,medicine.disease ,female genital diseases and pregnancy complications ,Endocrinology ,chemistry ,Adenylyl Cyclase Inhibitors ,Uterine Neoplasms ,Female ,Cyclase activity ,Developmental Biology - Abstract
The mechanisms responsible for the growth of uterine leiomyoma (a frequent cause of infertility in women) are largely unknown. Some data supports that cAMP plays a role in the growth of uterine cells but there are no reports on the status of the cAMP producing system in this human benign neoplasia. In this study, biopsies from leiomyoma and the adjacent myometrium were taken from menstruating women subjected to total hysterectomy for leiomyoma. Adenylate cyclase activity was determined by a protein-binding method, and the expression of alpha(s), alphai1/2, alphai3 and alphai0) G-protein subunits was analysed by immunoblot. The leiomyoma samples exhibited a decreased expression of as and ai1/2 with respect to the adjacent myometrial tissue. No differences were observed in alphai3 and alphaio protein expression. The basal adenylate cyclase activity as well as the efficacy (as assessed by the maximal stimulation levels) of either forskolin or, to a lesser extent, Gpp[NH]p on stimulation the enzyme activity was significantly lower in leiomyoma than in myometrium, whereas the potency (as assessed by the ED50 values) of these two agents did not vary. Present data indicate that the human leiomyoma is associated with low levels of cAMP. It is conceivable that the loss of sensitivity of adenylate cyclase to endogenous regulatory molecules could be related to the pathogenesis of human leiomyomas given that cAMP inhibits the MAP-kinase cascade in uterine tissues.
- Published
- 2001
139. Focusing attention on sound
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Andrew J. King and Victoria M. Bajo
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geography ,Frontal cortex ,geography.geographical_feature_category ,General Neuroscience ,Sensory system ,behavioral disciplines and activities ,nervous system ,otorhinolaryngologic diseases ,Focusing attention ,Psychology ,Neuroscience ,psychological phenomena and processes ,Sound (geography) ,Meaning (linguistics) ,Cognitive psychology - Abstract
A new study finds that neurons in the ferret frontal cortex typically respond to sound only during trained auditory tasks and that these neurons depict the task-related meaning rather than the acoustical properties of stimuli.
- Published
- 2010
- Full Text
- View/download PDF
140. Expression of vasoactive intestinal peptide (VIP) receptors in human uterus
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Ana M. Bajo, Juan C. Prieto, Pedro L. Valenzuela, Maria G. Juarranz, Luis G. Guijarro, and Pilar Martinez
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Adult ,medicine.medical_specialty ,Physiology ,Receptors, Vasoactive Intestinal Polypeptide, Type I ,Vasoactive intestinal peptide ,Neuropeptide ,Ovary ,Stimulation ,Biology ,Endometrium ,Biochemistry ,Adenylyl cyclase ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,Endocrinology ,Internal medicine ,medicine ,Humans ,Receptor ,Fallopian Tubes ,Dose-Response Relationship, Drug ,Uterus ,Myometrium ,Middle Aged ,medicine.anatomical_structure ,chemistry ,Receptors, Vasoactive Intestinal Peptide ,Receptors, Vasoactive Intestinal Peptide, Type II ,Female ,hormones, hormone substitutes, and hormone antagonists ,Adenylyl Cyclases ,Protein Binding - Abstract
We show the existence of functional vasoactive intestinal peptide (VIP) receptors in normal human female genital tract (endometrium, myometrium, ovary and Fallopian tube) as well as in leiomyoma (a frequent uterine pathology). The correlation between VIP binding and stimulation of adenylyl cyclase activity for all studied tissues was linear ( r = 0.86) suggesting the expression of VIP receptors throughout the human female genital tract. Immunodetection of VIP receptor subtypes gave different molecular weights for VPAC 1 (47 kDa primarily) and VPAC 2 (65 kDa), which may be due to different glycosylation extents. In conclusion, this study demonstrates the expression of both subtypes of VIP receptors and their functionality in human female genital tract, suggesting that this neuropeptide could play an important physiological and pathophysiological role at this level.
- Published
- 2000
141. Nerve growth factor modulates information processing in the auditory thalamus
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G. Vantini, Alessandro E. P. Villa, and V. M. Bajo Lorenzana
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Thalamic reticular nucleus ,Time Factors ,biology ,Chemistry ,General Neuroscience ,Thalamus ,Central nervous system ,Medial geniculate body ,Choline O-Acetyltransferase ,Rats ,Electrophysiology ,medicine.anatomical_structure ,Nerve growth factor ,Neuromodulation ,Neural Pathways ,medicine ,biology.protein ,Animals ,Female ,Nerve Growth Factors ,Evoked Potentials ,Neuroscience ,Neurotrophin - Abstract
The spatio-temporal organization of spike discharges was studied in rat auditory thalamus (i.e., medial geniculate body and auditory sector of thalamic reticular nucleus) following a 2-week continuous intracerebroventricular administration of nerve growth factor (NGF). Recording of extracellular single-unit activity indicated that, in medial geniculate body, NGF induced a significant increase of the mean firing rate. In thalamic reticular nucleus, where units tend to discharge in bursts, NGF increased the average burst size (number of spikes) and the intraburst frequency without affecting the firing rate. Following white noise acoustical stimulation, in medial geniculate body, more onset excitation and a lower signal-to-noise ratio were observed in NGF-treated rats than in controls. Conversely, in thalamic reticular nucleus, NGF-treated animals showed more inhibitory responses than controls. In addition, within the medial geniculate body, functional interactions between pairs of units simultaneously recorded from different electrodes were greatly increased by the nerve growth factor treatment. These data indicate that modifications of temporal pattern of discharges in selected brain regions are among the effects induced by the intracerebroventricular administration of nerve growth factor.
- Published
- 1999
142. Topographic organization of the dorsal nucleus of the lateral lemniscus in the cat
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V M, Bajo, M A, Merchán, M S, Malmierca, F R, Nodal, and J G, Bjaalie
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Brain Mapping ,Auditory Pathways ,Cats ,Image Processing, Computer-Assisted ,Animals ,Biotin ,Dextrans ,Iontophoresis ,Inferior Colliculi ,Brain Stem ,Fluorescent Dyes - Abstract
The dorsal nucleus of the lateral lemniscus (DNLL) is an auditory structure of the brainstem. It plays an important role in binaural processing and sound localization and it provides the inferior colliculus with an inhibitory projection. The DNLL is a highly conserved auditory structure across mammals, but differences among species in its detailed organization have been reported. The main goal of this study was to analyze the topographic organization of the cat DNLL. Single, small iontophoretic injections of biotinylated dextran amine were made at different loci in the central nucleus of the inferior colliculus (CNIC). The distribution of the labeled structures in the ipsi- and contralateral DNLL was computer reconstructed in three dimensions. In individual sections, a band of labeling is seen in the DNLL on both sides. These two labeled bands occupy symmetric locations and are made of retrogradely labeled neurons with flattened dendritic arbors oriented parallel to each other. Moreover, the ipsilateral labeled band contains labeled terminal fibers parallel to the labeled dendrites. With three-dimensional reconstructions, it becomes evident that the labeled band seen in each individual DNLL section represents a slice through a rostrocaudally oriented lamina. The shape, size, orientation, and location of this lamina change as the injection site is shifted along the tonotopic axis of the CNIC. An injection in the low-frequency region of the CNIC, produces a lamina that resembles a flattened tube located in the dorsolateral corner of the DNLL. An injection in the high-frequency region of the CNIC, by contrast, results in a lamina that is an elongated sheet located at the ventromedial surface of the DNLL. The laminae of the DNLL might constitute the structural basis for its tonotopical organization. Previous studies (Merchan MA, et al. 1994. J Comp Neurol 342:259-278) in conjunction with our current results suggest that the laminar organization in the DNLL might be common among mammals.
- Published
- 1999
143. Do auditory responses recorded from awake animals reflect the anatomical parcellation of the auditory thalamus?
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Fernando R. Nodal, Victoria M. Bajo, Jean-Marc Edeline, Yves Manunta, Neurobiologie de l'apprentissage, de la mémoire et de la communication (NAMC), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), and Laboratorio de Neurobiologı́a de la Audición, Instituto de Neurociencias de Castilla y León
- Subjects
Dorsum ,Male ,Auditory Pathways ,Consciousness ,media_common.quotation_subject ,Thalamus ,Central nervous system ,Guinea Pigs ,Arousal ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Reaction Time ,Animals ,Neurons, Afferent ,Pitch Perception ,030304 developmental biology ,media_common ,0303 health sciences ,Geniculate Bodies ,Auditory Threshold ,Medial geniculate body ,Sensory Systems ,Electrophysiology ,medicine.anatomical_structure ,Acoustic Stimulation ,Evoked Potentials, Auditory ,[SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC] ,Psychology ,Auditory Physiology ,Neuroscience ,030217 neurology & neurosurgery ,Vigilance (psychology) - Abstract
Previous studies performed in anesthetized animals have shown differences between the acoustic responses of neurons recorded from the different divisions of the medial geniculate body (MGB). This study aimed at determining whether or not such differences are also expressed when neurons are recorded from awake animals. The auditory responses of 130 neurons of the auditory thalamus were determined in awake, restrained guinea pigs while the state of vigilance of the animals was continuously monitored. There were significantly more 'on' phasic evoked responses and significantly fewer 'non-responsive' or 'labile' cells in the ventral division of the MGB (MGv) than in the other divisions. The response latencies and the variability of the latencies were smaller in the MGv than in the other divisions. The tuning of the neurons obtained from MGv and from the lateral part of the posterior complex were significantly sharper than those coming from the dorsal division of the MGB and the medial division. The mean threshold and the percentage of monotonic vs. non-monotonic intensity functions were not different in the subdivisions of the auditory thalamus. When compared with previous studies, the quantifications of the acoustic responses obtained in the present study gave values that differed from those reported under deep anesthesia, but were close to those reported under light anesthesia. Lastly, even if none of the physiological characteristic makes it possible, by itself, to determine the locus of recordings in the auditory thalamus, we conclude that the physiological characteristics of the evoked responses obtained in MGv differ from those of other divisions.
- Published
- 1999
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144. Muscarinic activation of a non-selective cationic conductance in pyramidal neurons in rat basolateral amygdala
- Author
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Javier Yajeya, Victoria M. Bajo, A.S. Riolobos, José María Criado, Margarita Heredia, and A de la Fuente Juan
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Male ,medicine.medical_specialty ,Carbachol ,Cesium ,In Vitro Techniques ,Membrane Potentials ,Internal medicine ,Muscarinic acetylcholine receptor ,medicine ,Extracellular ,Animals ,Rats, Wistar ,Neurons ,Gallamine Triethiodide ,Chemistry ,Inward-rectifier potassium ion channel ,General Neuroscience ,Pyramidal Cells ,Depolarization ,Pirenzepine ,Hyperpolarization (biology) ,Amygdala ,Rats ,Endocrinology ,Barium ,Biophysics ,Calcium ,Female ,Acetylcholine ,Flunarizine ,medicine.drug - Abstract
In the present study, a cationic membrane conductance activated by the acetylcholine agonist carbachol was characterized in vitro in neurons of the basolateral amygdala. Extracellular perfusion of the K+ channel blockers Ba2+ and Cs+ or loading of cells with cesium acetate did not affect the carbachol-induced depolarization. Similarly, superfusion with low-Ca2+ solution plus Ba2+ and intracellular EGTA did not affect the carbachol-induced depolarization, suggesting a Ca2+-independent mechanism. On the other hand, the carbachol-induced depolarization was highly sensitive to changes in extracellular K+ or Na+. When the K+ concentration in the perfusion medium was increased from 4.7 to 10 mM, the response to carbachol increased in amplitude. In contrast, lowering the extracellular Na+ concentration from 143.2 to 29 mM abolished the response in a reversible manner. Results of coapplication of carbachol and atropine, pirenzepine or gallamine indicate that the carbachol-induced depolarization was mediated by muscarinic cholinergic receptors, but not the muscarinic receptor subtypes M1, M2 or M4, specifically. These data indicate that, in addition to the previously described reduction of a time- and voltage-independent K+ current (IKleak), a voltage- and time-dependent K+ current (IM), a slow Ca2+-activated K+ current (sIahp) and the activation of a hyperpolarization-activated inward rectifier K+ current (IQ), carbachol activated a Ca2+-independent non-selective cationic conductance that was highly sensitive to extracellular K+ and Na+ concentrations.
- Published
- 1999
145. Réplica
- Author
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Luis T. Mercé, Juan L. Alcázar, M. Jesús Barco, Santiago Bau, Rosa Sabatel, Juan M. Troyano, and José M. Bajo
- Subjects
Obstetrics and Gynecology - Published
- 2008
- Full Text
- View/download PDF
146. Discharge properties of single neurons in the dorsal nucleus of the lateral lemniscus of the rat
- Author
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Victoria M. Bajo, Eric M. Rouiller, F. de Ribaupierre, and Alessandro E. P. Villa
- Subjects
Inferior colliculus ,Action Potentials ,Inhibitory postsynaptic potential ,Functional Laterality ,Membrane Potentials ,Bursting ,Evoked Potentials, Auditory, Brain Stem ,Animals ,Rats, Wistar ,Neurons ,Behavior, Animal ,Chemistry ,General Neuroscience ,Lateral lemniscus ,Auditory Threshold ,Anatomy ,Vestibulocochlear Nerve ,Rats ,Electrophysiology ,Acoustic Stimulation ,Excitatory postsynaptic potential ,Tonotopy ,Extracellular Space ,Noise ,Neuroscience ,Binaural recording ,Brain Stem - Abstract
The aim of the present study was to characterize the discharge properties of single neurons in the dorsal nucleus of the lateral lemniscus (DNLL) of the rat. In the absence of acoustic stimulation, two types of spontaneous discharge patterns were observed: units tended to fire in a bursting or in a nonbursting mode. The distribution of units in the DNLL based on spontaneous firing rate followed a rostrocaudal gradient: units with high spontaneous rates were most commonly located in the rostral part of the DNLL, whereas in the caudal part units had lower spontaneous discharge rates. The most common response pattern of DNLL units to 200 ms binaural noise bursts contained a prominent onset response followed by a lower but steady-state response and an inhibitory response in the early-off period. Thresholds of response to noise bursts were on average higher for DNLL units than for units recorded in the inferior colliculus under the same experimental conditions. The DNLL units were arranged according to a mediolateral sensitivity gradient with the lowest threshold units in the most lateral part of the nucleus. In the rat, as in other mammals, the most common DNLL binaural input type was an excitatory response to contralateral ear stimulation and inhibitory response to ipsilateral ear stimulation (EI type). Pure tone bursts were in general a more effective stimulus compared to noise bursts. Best frequency (BF) was established for 97 DNLL units and plotted according to their spatial location. The DNLL exhibits a loose tonotopic organization, where there is a concentric pattern with high BF units located in the most dorsal and ventral parts of the DNLL and lower BF units in the middle part of the nucleus.
- Published
- 1999
147. Inguinal Lymphadenectomy Assessment Associated with Penile Carcinoma Undergone New Strategies for Nodal Staging
- Author
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Gomez, Victor J. Ovejero, primary, Cuesta, L. Martin, additional, Bretones, F. Martinez, additional, Bellido, T. Gallego, additional, Lahoz, L. A. Asensio, additional, Torre, J. Villalba, additional, Setien, A. Ingelmo, additional, and Arenas, J. M. Bajo, additional
- Published
- 2014
- Full Text
- View/download PDF
148. Anatomic evidence of a three-dimensional mosaic pattern of tonotopic organization in the ventral complex of the lateral lemniscus in cat
- Author
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Trygve B. Leergaard, Manuel S. Malmierca, Victoria M. Bajo, Miguel A. Merchán, and Jan G. Bjaalie
- Subjects
Inferior colliculus ,Auditory Pathways ,Efferent ,Biotin ,Axonal Transport ,Article ,Image Processing, Computer-Assisted ,medicine ,Animals ,Auditory system ,Pitch Perception ,Cochlea ,Fluorescent Dyes ,Brain Mapping ,Biotinylated dextran amine ,Chemistry ,General Neuroscience ,Ventral Tegmental Area ,Lateral lemniscus ,Dextrans ,Anatomy ,Inferior Colliculi ,medicine.anatomical_structure ,Cats ,Auditory nuclei ,Tonotopy ,Neuroscience ,Brain Stem - Abstract
The ventral complex of the lateral lemniscus (VCLL, i.e., the ventral and intermediate nuclei) is composed of cells embedded in the fibers of the lateral lemniscus. These cells are involved in the processing of monaural information and receive input from the collaterals of the fibers ascending to the inferior colliculus. Whereas tonotopic organization is a feature of all other nuclei of the auditory system, this functional principle is debated in the VCLL. We have made focal injections of the tracer biotinylated dextran amine into different frequency band representations of the inferior colliculus in cat. Retrogradely labeled cells and terminal fibers (collaterals of efferent local axons and other ascending lemniscal fibers) were found in the ipsilateral VCLL. The spatial distribution of the labeling was analyzed using three-dimensional (3-D) reconstruction and computer graphical visualization techniques. A complex topographic organization was found. In all cases, labeled fibers and cells were distributed in multiple clusters throughout the dorsoventral extent of the VCLL. The shape, size, and location of the labeled clusters suggest an interdigitation of clusters assigned to different frequency-band representations. But an overall mediolateral distribution gradient was observed, with high frequencies represented medially and lower frequencies progressively more laterally.We conclude that the clusters may represent discontinuous frequency-band compartments as a counterpart to the continuous laminar compartments in the remaining auditory nuclei. The 3-D orderly mosaic pattern indicates that the VCLL preserves the spectral decomposition originated in the cochlea in a way that facilitates across-frequency integration.
- Published
- 1998
149. The Nuclei of the Lateral Lemniscus
- Author
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Victoria M. Bajo, Jan G. Bjaalie, Manuel S. Malmierca, and Miguel A. Merchán
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Inferior colliculus ,Physics ,Superior olivary complex ,Lateral lemniscus ,otorhinolaryngologic diseases ,Interaural time difference ,Brainstem ,Monaural ,Neuroscience ,Binaural recording ,Cochlear nucleus - Abstract
A unique feature of the auditory brainstem is the divergent/convergent nature of the path- ways from the auditory nerve to the inferior colliculus (IC, reviewed in Irvine, 1992). Some of the projections from the cochlear nucleus complex to the IC are direct while others are indirect via the superior olivary complex and the nuclei of the lateral lemniscus (NLL). In these nuclei, sig- nificant monaural and binaural information are extracted from the auditory signal.
- Published
- 1997
- Full Text
- View/download PDF
150. Assessment with transvaginal ultrasonography of endometrial thickness in women with postmenopausal bleeding
- Author
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F, Mateos, R, Zarauz, C, Seco, J R, Rayward, P, del Barrio, J, Aguirre, and J M, Bajo
- Subjects
Adult ,Aged, 80 and over ,Postmenopause ,Endometrium ,Endometrial Hyperplasia ,Humans ,Female ,Uterine Hemorrhage ,Middle Aged ,Aged ,Ultrasonography - Abstract
The aim of this study was to assess the use of transvaginal ultrasonography in measuring endometrial thickness in postmenopausal women with bleeding, thus to determine the least invasive treatment.We evaluated 168 women with postmenopausal bleeding by transvaginal ultrasonography and histological study of the endometrium.No cancerous or precancerous lesions were found when endometrial thickness was under 10 mm. The mean endometrial thickness in women with cancerous and precancerous lesions was 10.75 +/- 1.63 mm, while in non-pathological lesions it was 1.36 +/- 1.18 mm.To diagnose endometrial pathology, an endometrial thickness over 6 mm yields a sensitivity of 88.6%, a specificity of 90.6%, a positive predictive value of 92%, with 4.6% of false-positives and 4.6% of false-negatives (six small polyps and one irregular maturation). Although we are waiting for other prospective and multicentric studies, our present experience leads us to believe that Dilatation and Curettage (DC) can be avoided in postmenopausal bleeding with endometrial thickness under or equal to 6 mm.
- Published
- 1997
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