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1.
J Biomed Nanotechnol ; 16(5): 689-701, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32919488

RESUMO

Developments in the design of lanthanide oxide nanoparticles (NPs) have unleashed a wide variety of biomedical applications. Several types of hepatic cancer cells overexpress two proteins: the gastrin-releasing peptide receptor (GRPr), which specifically recognizes the bombesin (BN) peptide, and the prostate-specific membrane antigen (PSMA), which specifically binds to several peptides that inhibit its activity (iPSMA). This research synthesized and physicochemically characterized Sm2O3 nanoparticles functionalized with the iPSMA-BN heterodimeric peptide and studied the effects on their structural, biochemical and preclinical properties after activation by neutron irradiation for possible use in molecular dual-targeted radiotherapy of hepatocellular carcinoma. The Sm2O3 NPs were synthesized by the precipitation-calcination method and functionalized with iPSMA-BN peptide using the DOTA macrocycle as a linking agent. Analysis of physicochemical characterization via TEM, EDS, XRD, UV-Vis, FT-IR, DSL, and zeta potential results showed the formation of Sm2O3-iPSMA-BN NPs (94.23 ± 5.98 nm), and their physicochemical properties were not affected after neutron activation. The nanosystem showed a high affinity with respect to PSMA and GRPr in HepG2 cells ( Kd = 6.6 ± 1.6 nM) and GRPr in PC3 cells ( Kd = 10.6 ± 1.9 nM). 153Sm2O3-iPSMA-BN NPs exhibited radioluminescent properties, making possible in vivo optical imaging of their biodistribution in mice. The results obtained from this research support further preclinical studies designed to evaluate the dosimetry and therapeutic efficacy of 153Sm2O3-iPSMA-BN nanoparticles for in vivo imaging and molecular dual-targeted radiotherapy of liver tumors overexpressing PSMA and/or GRPr proteins.


Assuntos
Nanopartículas Metálicas , Animais , Bombesina , Linhagem Celular Tumoral , Humanos , Camundongos , Óxidos , Radioisótopos , Samário , Espectroscopia de Infravermelho com Transformada de Fourier , Distribuição Tecidual
2.
Mater Sci Eng C Mater Biol Appl ; 117: 111335, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32919684

RESUMO

Among the nanomaterials, rare sesquioxides (lanthanide oxides such as Lu2O3) are of interest due to their adequate thermal conductivity, excellent chemical stability, and high light output. The prostate-specific membrane antigen (PSMA) is an integral multifunctional protein overexpressed in various types of cancer cells. The radiolabeled PSMA inhibitor peptides (iPSMA) have demonstrated their usefulness as specific probes in the treatment and detection of a wide variety of neoplasms, mainly due to their high in vivo recognition by the PSMA protein. The objective of this research was to synthesize Lu2O3-iPSMA nanoparticles (NPs) and characterize their physicochemical properties before and after neutron activation, as well as to assess their biodistribution profile and in vitro potential to target cells overexpressing PSMA. The Lu2O3 NPs were synthesized by the precipitation-calcination method and conjugated to the iPSMA peptide using DOTA (1,4,7,10-tetraazocyclodecane-N,N',N″,N‴-tetraacetic acid) as a linking agent. Results of the physicochemical characterization by FT-IR and UV-Vis spectroscopies, SEM, TEM, DLS, HRTEM, SAED, DSC-TGA, and X-ray diffraction indicated the formation of Lu2O3-iPSMA NPs (diameter of 29.98 ± 9.07 nm), which were not affected in their physicochemical properties after neutron activation. 177Lu2O3-iPSMA NPs showed high affinity (Kd = 5.7 ± 1.9 nM) for the PSMA protein, evaluated by the saturation assay on HepG2 hepatocellular carcinoma cells (PSMA-positive). The biodistribution profile of the nanosystem in healthy mice showed the main uptake in the liver. After irradiation, radioactive Lu2O3-iPSMA NPs exhibited radioluminescent properties, making the in vivo acquisition of their biodistribution, via optical imaging, possible. The results obtained from this research validate the execution of additional preclinical studies with the objective of evaluating the potential of the 177Lu2O3-iPSMA NPs for the targeted radiotherapy and in vivo imaging of tumors overexpressing the PSMA protein.


Assuntos
Nanopartículas , Neoplasias da Próstata , Animais , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Nêutrons , Óxidos , Espectroscopia de Infravermelho com Transformada de Fourier , Distribuição Tecidual
3.
Rehabil Res Pract ; 2016: 8109365, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27195152

RESUMO

Objectives. (1) To describe the epidemiological and medical features of a sample with LLA and LLD in childhood and (2) to explore their relationship with subsequent physical and psychosocial functions in adulthood. Methods. Cross-sectional survey. Demographics, medical data, Locomotor Capabilities Index (LCI), and Discomfort-Engagement in Everyday Activities Involving Revealing the Body Scale (D-EEARB) were collected from thirty-two adults who suffered from LLA in childhood or LLD. Results. Most of the sample (53.1% males) was working (84.4%), living independently (75%), and single (75%). Mean age was 33.16 (SD = 7.64, range 18-50). Leading causes for LLA were traumatic (40.6%) and oncologic (25%). LLD was present in 6 cases (18.8%). LCI scores revealed a high performance among males (t 17,464 = 2.976, p = .008). D-EEARB scores showed that 56.25% stated feeling "quite" or "totally comfortable" in situations which involved revealing their body, but 43.75% stated the contrary ("uncomfortable" or "very uncomfortable"). LLD and traumatic LLA show higher scores in D-EEARB than vascular and oncological LLA (χ (2) = 7.744, df = 3, p = .05). Conclusions. Adults suffering from LLDs and LLAs during childhood seem to perform well once they are adults. However, 43.75% of patients express considerable discomfort in situations that involve revealing the body.

4.
J Neuroendocrinol ; 28(4)2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26613552

RESUMO

Prenatal stress (PNS) affects a number of traits in the offspring, including stress axis regulation, emotionality and cognition; however, much less is known about the effects of PNS on social memory and the underlying central mechanisms. In the present study, we investigated social preference, social memory under basal and stress conditions and olfactory memory for social and nonsocial odours in the adult offspring of dams exposed to social stress during late pregnancy. Given the key roles that the central oxytocin and vasopressin systems play in facilitating social memory, we further investigated the effects of PNS on the central expression of mRNA for oxytocin (Oxtr) and vasopressin-1a (Avpr1a) receptors. PNS did not affect social preference in either sex; however, social memory was impaired under basal conditions in PNS females but not PNS males. Accordingly, Avpr1a mRNA expression in the lateral septum and bed nucleus of stria terminalis (BNST) was unaltered in males but was significantly lower in PNS females compared to controls. No differences in Oxtr mRNA expression were detected between control and PNS offspring in either sex in any of the brain regions examined. Social memory deficits in PNS females persisted when social odours were used; however, this does not appear to be a result of impaired olfaction because memory for nonsocial odours was similar in control and PNS females. Under acute stress conditions, deficits in social memory were observed in both male and female control offspring; however, PNS males were unaffected. Moreover, acute stress facilitated social memory in PNS females and this was associated with an up-regulation of Avpr1a mRNA in the lateral septum and BNST. Our data support a role for altered signalling via central Avpr1a in PNS-induced sex-dependent changes in social memory and may have implications for understanding the aetiology of neurodevelopmental disorders characterised by social behaviour deficits in humans.


Assuntos
Memória/fisiologia , Receptores de Vasopressinas/fisiologia , Caracteres Sexuais , Comportamento Social , Estresse Psicológico/metabolismo , Animais , Comportamento de Escolha , Feminino , Masculino , Percepção Olfatória/fisiologia , Ocitocina/biossíntese , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Ratos , Receptores de Vasopressinas/biossíntese , Núcleos Septais/metabolismo
5.
Rev. salud pública (Córdoba) ; 19(2): 24-33, 2015.
Artigo em Espanhol | LILACS | ID: lil-779379

RESUMO

La presente investigación tiene el propósito de describir el proceso de formación en investigación-acción efectuada en la integración realizada por dos cátedras de la Carrera del Profesorado Universitario: Investigación educativa y Didáctica Especial producto de siete años de trabajo.Dicho proceso se sostiene a partir del reconocimiento de problemáticas planteadas por los alumnos-profesionales,en su trabajo como docentes. La construcción del problema de investigación requiere de diferentes estrategias pedagógicas. La metodología se basó en el enfoque de investigación-acción. Los resultados confirman que la integración inter cátedras un elemento clave para transformar el quehacer universitario y es una alternativa para fomentar y desarrollar la investigación científica que contribuya al mejoramiento y transformación de la sociedad, como uno de los objetivos de la Universidad Católica de Córdoba a la par que se constituye en una estrategia para el acuerdo, los consensos, la innovación e investigación que están en consonancia con la misión institucional...


The purpose of this research is to describe the training process in research-action that tookplace in the integration of Educational Research and Special Didactics; two chairs of thecourse of studies University Teaching, result of seven-year-work. Said process arises from theacknowledgment of issues proposed by students-professionals in their work as teachers. Theconstruction of the research problem requires different pedagogic strategies. Methodologywas based on the research-action approach. Results confi rm that inter-chair integrationis a key factor to transform university tasks and an alternative to encourage and developscientifi c research helping to improve and transform society as one of the objectives on theCatholic University of Cordoba. At the same time, it is becoming a strategy for agreement,consensus, innovation and investigation, consistent with the institutional mission...


Assuntos
Humanos , Masculino , Feminino , Ensino de Recuperação , Pesquisa Científica e Desenvolvimento Tecnológico , Recursos para a Pesquisa
6.
Transbound Emerg Dis ; 60 Suppl 2: 131-6, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24589113

RESUMO

Babesia bovis is a tick-transmitted haemoprotozoan and a causative agent of bovine babesiosis, a cattle disease that causes significant economic loss in tropical and subtropical regions. A panel of nineteen micro- and minisatellite markers was used to estimate population genetic parameters of eighteen parasite isolates originating from different continents, countries and geographic regions including North America (Mexico, USA), South America (Argentina, Brazil), the Middle East (Israel) and Australia. For eleven of the eighteen isolates, a unique haplotype was inferred suggesting selection of a single genotype by either in vitro cultivation or amplification in splenectomized calves. Furthermore, a high genetic diversity (H = 0.780) over all marker loci was estimated. Linkage disequilibrium was observed in the total study group but also in sample subgroups from the Americas, Brazil, and Israel and Australia. In contrast, corresponding to their more confined geographic origin, samples from Israel and Argentina were each found to be in equilibrium suggestive of random mating and frequent genetic exchange. The genetic differentiation (F(ST)) of the total study group over all nineteen loci was estimated by analysis of variance (Θ) and Nei's estimation of heterozygosity (G(ST')) as 0.296 and 0.312, respectively. Thus, about 30% of the genetic diversity of the parasite population is associated with genetic differences between parasite isolates sampled from the different geographic regions. The pairwise similarity of multilocus genotypes (MLGs) was assessed and a neighbour-joining dendrogram generated. MLGs were found to cluster according to the country/continent of origin of isolates, but did not distinguish the attenuated from the pathogenic parasite state. The distant geographic origin of the isolates studied allows an initial glimpse into the large extent of genetic diversity and differentiation of the B. bovis population on a global scale.


Assuntos
Babesia bovis/classificação , Babesiose/epidemiologia , Doenças dos Bovinos/epidemiologia , Variação Genética , Animais , Argentina/epidemiologia , Babesia bovis/genética , Babesia bovis/isolamento & purificação , Babesiose/parasitologia , Babesiose/transmissão , Bovinos , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/transmissão , Surtos de Doenças , Genótipo , Turquia/epidemiologia
7.
Rev. salud pública Parag ; 2(2): [P39-P42], jul - dic 2012.
Artigo em Espanhol | LILACS | ID: biblio-965902

RESUMO

Introducción: La Tuberculosis (TB) es una enfermedad endémica en Paraguay, en el año 2010 se reportaron 2313 casos. La presentación extrapulmonar se observa en un 10-20% de los casos y en pacientes inmunocomprometidos puede llegar al 60%. La tuberculosis vertebral puede afectar la columna vertebral, con mayor frecuencia las vértebras T8 hasta L3. Tiene su origen en un foco primario pulmonar, que favorece uno secundario a nivel óseo. El diagnostico oportuno de la TB delimita la progresión a esta complicación y a las consecuencias para la vida del paciente. Caso Clínico: Paciente de sexo femenino de 42 años, fumadora de larga data, consulta por dolor en columna dorsal de 3 meses de evolución y pérdida de peso progresiva de aproximadamente 5 kg, con deformidad ósea progresiva de la columna dorsal. Al cuadro se agrega tos de 2 meses de evolución, seca al inicio y volviéndose productiva 15 días antes de la consulta. Niega sensación febril. Al examen físico se observa cifosis dorsal marcada y relieves óseos prominentes. En la Rx de torax se observan infiltrados bilaterales difusos miliariformes y leve desviación de la columna. El diagnostico definitivo fue Tuberculosis vertebral por lo que se inicia el tratamiento con HRZE (Rifampicina, Pirazinamida, Isoniazida, Etambutol) y se la deriva a neurocirugía para corrección de la deformidad ósea. Actualmente la paciente se encuentra en fase de recuperación con buena evolución tras cirugía correctiva. Discusión: Como en la mayoría de los casos reportados el síntoma cardinal fue el dolor. La imagenología es un pilar fundamental del diagnostico, brinda evidencia de la extensión de la lesión vertebral para decidir conducta. El alivio sintomático solo se logra con la cirugía correctiva. Debemos pensar y buscar tuberculosis en todo paciente sintomático respiratorio; las complicaciones extrapulmonares pueden evitarse mediante el diagnostico precoz y tratamiento adecuado de esta enfermedad de elevada prevalencia en nuestro país. Palabras clave: Espondilitis; Tuberculosis espinal; Mal de Pott.


Introduction: Tuberculosis (TB) is an endemic disease in Paraguay; in 2010 2313 cases were reported. Extrapulmonary presentation occurred in about 10 to 20% of cases, and in immunocompromised patients can go up to 60%. Vertebral tuberculosis can affect the spine, and is more frequent from T8 to L3. It has its origin in a primary pulmonary nodule from which can seed a secondary process in these bones. Early diagnosis of TB limits this complication and improved the quality of life of these patients. Case: 42 years old female, smoker, came for an evaluation of pain on her dorsal spine for the past 3 months, progressive loss weight of about 5 kilos, and bone deformity of the dorsal spine. 2 months prior this visit, she started coughing, described as dry, and then becomes wet 15 days before this visit. She denies fever and on physical examination there is a severe dorsal kyphosis with prominent bony prominence. CXR showed a miliary, diffuse, bilateral infiltrates with a slight deviation of the dorsal spine. Final diagnosis was vertebral tuberculosis, and treatment with HRZE (Rifampin, Pyrazinamide, Isoniazid and Ethambutol) was started. The patient was sent to neurosurgery for correction of the spine deformity. Currently she is stable, after corrective spine surgery. Discussion: Lijke in most reported cases, de cardinal symptom was pain, and imaging is fundamental for making a diagnosis and helps determine the extension of the vertebral disease to decide the treatment approach. Pain is controlled only with corrective surgery. We should think and look for TB in every patient with respiratory symptoms; the extrapulmonary complications could be avoided throu and early diagnosis and appropriate treatment of this disease, which has a high prevalence in our country. Key words: Spondylitis, spinal tuberculosis,Pott´s disease.


Assuntos
Humanos , Feminino , Adulto , Paraguai/epidemiologia , Tuberculose da Coluna Vertebral
8.
Am J Physiol Cell Physiol ; 297(3): C611-20, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19570890

RESUMO

Epithelia can adjust the permeability of the paracellular permeation route by regulating the degree of sealing of the tight junction. This is reflected by a transepithelial electrical resistance (TER) ranging from a few tenths to several thousand ohms times square centimeters, depending on the difference in composition between the fluid in the lumen and the interstitial fluid. Although teleologically sound, such correlation requires a physiological explanation. We have previously shown that urine extracts from different animal species increase the TER of Madin-Darby canine kidney (MDCK) monolayers and that these effects are mediated by epidermal growth factor (EGF) contained in the flowing intratubular fluid that eventually reaches the urine. This increase in TER is accompanied by an enhanced expression of claudin-4 (cln-4) and a decrement of cln-2. These changes are transient, peaking at approximately 16 h and returning to control values in approximately 24 h. In the present work we investigated how EGF provokes this transient response, and we found that the activation of extracellular-regulated kinases 1/2 (ERK1/2) by EGF is essential to increase TER and cln-4 content, but it does not appear to participate in cln-2 downregulation. On the other hand, prostaglandin synthesis, stimulated by EGF, functions as a negative feedback, turning off the signal initiated by EGF. Thus, PGE(2) blocks ERK1/2 by a mechanism that involves the G alpha(s) protein, adenylyl cyclase as well as protein kinase A in MDCK cells. In summary, the permeability of a given segment of the nephron depends on the expression of different claudin types, which may be modulated by EGF and prostaglandins.


Assuntos
Dinoprostona/farmacologia , Fator de Crescimento Epidérmico/farmacologia , Junções Íntimas/fisiologia , Animais , Linhagem Celular , Colforsina , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Cães , Impedância Elétrica , Fator de Crescimento Epidérmico/metabolismo , Células Epiteliais , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação da Expressão Gênica/fisiologia , Humanos , Receptores de Prostaglandina E/genética , Receptores de Prostaglandina E/metabolismo
9.
Rev. salud pública (Córdoba) ; 13(1): 43-48, jun. 2009.
Artigo em Espanhol | LILACS | ID: lil-528888

RESUMO

Promoción y Educación para la Salud Social en Poblaciones Rurales tiene como objetivos desarrollaracciones de salud comprendidas y compartidas por losdiversos actores de la comunidad contribuyendo conla incorporación de hábitos saludables, identificacióny diagnóstico de problemas sanitarios y colaborar enla provisión de medicamentos para el control de laequinococosis en las comunidades rurales del partido deTandil.Posee financiamiento del Ministerio de Educación de laNación y la participación de las Facultades de CienciasVeterinarias y de Arte de la Universidad Nacional delCentro; dependencias gubernamentales de las áreas Salud yEducación de la Provincia de Buenos Aires y del Municipiode Tandil; el Rotary Club Tandil Norte y alumnos voluntariosde la universidad.La vinculación de la Universidad con su comunidadpermite desarrollar prácticas en el área de Salud Pública.La transmisión de valores y actitudes en la educaciónsuperior fortalece la formación de profesionales socialmente responsables.


Assuntos
Equinococose , População Rural , Responsabilidade Social , Saúde
10.
Vet Parasitol ; 162(3-4): 200-6, 2009 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-19376655

RESUMO

This paper reports two new quantitative PCR (qPCR) assays, developed in an attempt to improve the detection of bovine piroplasmids. The first of these techniques is a duplex TaqMan assay for the simultaneous diagnosis of Babesia bovis and B. bigemina. This technique is ideal for use in South America where bovids harbour no theilerids. The second technique, which is suitable for the diagnosis of both babesiosis and theileriosis worldwide, involves fluorescence resonance energy transfer (FRET) probes. In FRET assays, Babesia bovis, B. divergens, Babesia sp. (B. major or B. bigemina), Theileria annae and Theileria sp. were all identifiable based on the melting temperatures of their amplified fragments. Both techniques provided linear calibration curves over the 0.1fg/microl to 0.01ng/microl DNA range. The assays showed good sensitivity and specificity. To assess their performance, both procedures were compared in two separate studies: the first was intended to monitor the experimental infection of calves with B. bovis and the second was a survey where 200 bovid/equine DNA samples from different countries were screened for piroplasmids. Comparative studies showed that duplex TaqMan qPCR was more sensitive than FRET qPCR in the detection of babesids.


Assuntos
Babesia/isolamento & purificação , Reação em Cadeia da Polimerase/veterinária , Theileria/isolamento & purificação , Animais , Babesiose/diagnóstico , Babesiose/veterinária , Bovinos , DNA de Protozoário , Transferência Ressonante de Energia de Fluorescência/métodos , Transferência Ressonante de Energia de Fluorescência/veterinária , Doenças dos Cavalos/diagnóstico , Cavalos , Reação em Cadeia da Polimerase/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Theileriose/diagnóstico
11.
Ann N Y Acad Sci ; 1149: 235-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19120219

RESUMO

An indirect ELISA (iELISA) for the detection of specific anti-Theileria equi antibodies in horse serum was developed. Its performance showed good concordance (K= 0.79) when compared with a competitive ELISA recommended by the World Organisation for Animal Health. Horse serum samples from two provinces located in the north and east of Argentina (Formosa and Entre Rios, respectively) were analyzed by this iELISA. A high percentage of positive horses were found in Formosa, consistent with the climatic conditions of the region that are apt for the development of tick vectors. Surprisingly, seropositive animals were also detected, although in a lower proportion, in Entre Rios, which has a temperate weather and is presumably tick free. Breeding of thoroughbred racing horses is an important economic asset of Argentina. Since equine piroplasmosis is a constraint for horse export, the epidemiological situation in different regions of the country needs to be assessed for the implementation of control measures. The iELISA developed in this work provides a convenient tool for this type of study.


Assuntos
Babesiose/veterinária , Ensaio de Imunoadsorção Enzimática/métodos , Doenças dos Cavalos/diagnóstico , Animais , Anticorpos Antiprotozoários/sangue , Babesiose/diagnóstico , Sequência de Bases , Primers do DNA , Cavalos
12.
Vet Parasitol ; 150(1-2): 155-8, 2007 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-17950535

RESUMO

The aim of the present work was to describe the occurrence of antibodies to Neospora caninum in water buffaloes on four ranches located in Corrientes province in the northeast of Argentina. Antibodies against N. caninum were determined in sera of 449 water buffaloes by using an indirect fluorescent antibody test (IFAT). A Bayesian logistic regression mixed model was used to quantify the strength of association between positive serological results to N. caninum and gender, age and category (calf, steer, heifer, cow) as risk factors. Antibody titers were found in 287 (64%) buffaloes. All ranches had seropositive animals. Age was more strongly associated with positive results to N. caninum (OR: 1.4; CI 95%: 0.86-2.22) than gender (OR: 1.02, CI 95%: 0.40-2.59) and category (OR: 0.88, CI 95%: 0.57-0.88). Results suggest a high exposure of water buffaloes to N. caninum by postnatal transmission in these four ranches located in Corrientes province, Argentina. Further studies are needed to quantify the consequences of Neospora-infections in the water buffalo industry.


Assuntos
Anticorpos Antiprotozoários/sangue , Búfalos/parasitologia , Coccidiose/veterinária , Neospora/imunologia , Envelhecimento , Animais , Argentina/epidemiologia , Coccidiose/sangue , Coccidiose/epidemiologia , Coccidiose/parasitologia , Feminino , Masculino , Fatores de Risco
13.
Vet Parasitol ; 147(1-2): 16-25, 2007 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-17466458

RESUMO

The haemoparasites Babesia bovis and Babesia bigemina affect cattle over vast areas of the tropics and temperate parts of the world. Microscopic examination of blood smears allows the detection of clinical cases of babesiosis, but this procedure lacks sensitivity when parasitaemia levels are low. In addition, differentiating between similar haemoparasites can be very difficult. Molecular diagnostic procedures can, however, overcome these problems. This paper reports a quantitative PCR (qPCR) assay involving the use of SYBR Green. Based on the amplification of a small fragment of the cytochrome b gene, this method shows both high sensitivity and specificity, and allows quantification of parasite DNA. In tests, reproducible quantitative results were obtained over the range of 0.1 ng to 0.1 fg of parasite DNA. Melting curve analysis differentiated between B. bovis and B. bigemina. To assess the performance of the new qPCR procedure it was used to screen for babesiosis in 40 cows and 80 horses. B. bigemina was detected in five cows (three of these were also found to be positive by standard PCR techniques targeting the 18S rRNA gene). In addition, B. bovis was detected in one horse and B. bigemina in two horses using the proposed method, while none was found positive by ribosomal standard PCR. The sequences of the B. bigemina cytochrome b and 18S rRNA genes were completely conserved in isolates from Spain and Argentina, while those of B. bovis showed moderate polymorphism.


Assuntos
Babesia bovis/isolamento & purificação , Babesia/isolamento & purificação , Babesiose/veterinária , Doenças dos Bovinos/diagnóstico , Doenças dos Cavalos/diagnóstico , Reação em Cadeia da Polimerase , Animais , Babesiose/diagnóstico , Bovinos , Citocromos b/genética , Cavalos , Dados de Sequência Molecular , Plasmídeos/genética , RNA Ribossômico 18S/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Br J Cancer ; 96(10): 1595-604, 2007 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-17486135

RESUMO

Prostate cancer represents a major concern in human oncology and the phytoalexin resveratrol (RES) inhibits growth and proliferation of prostate cancer cells through the induction of apoptosis. In addition, previous data indicate that in oestrogen-responsive human breast cancer cells, RES induces apoptosis by inhibition of the phosphoinositide-3-kinase (PI3K) pathway. Here, using androgen receptor (AR)-positive LNCaP and oestrogen receptor alpha (ERalpha)-expressing PC-3 prostate tumour cells, we have analysed whether the antiproliferative activity of RES takes place by inhibition of the AR- or ERalpha-dependent PI3K pathway. Although RES treatment (up to 150 microM) decreased AR and ERalpha protein levels, it did not affect AR and ERalpha interaction with p85-PI3K. Immunoprecipitation and kinase assays showed that RES inhibited AR- and ERalpha-dependent PI3K activities in LNCaP and PC-3, respectively. Consistently, lower PI3K activities correlated with decreased phosphorylation of downstream targets protein kinase B/AKT (PKB/AKT) and glycogen synthase kinase-3 (GSK-3). GSK-3 dephosphorylation could be responsible for the decreased cyclin D1 levels observed in both cell lines. Importantly, RES markedly decreased PKB/AKT phosphorylation in primary cultures from human prostate tumours, suggesting that the mechanism proposed here could take place in vivo. Thus, RES could have antitumoral activity in androgen-sensitive and androgen-non-sensitive human prostate tumours by inhibiting survival pathways such as that mediated by PI3K.


Assuntos
Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias da Próstata/metabolismo , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Receptores Androgênicos/metabolismo , Receptores de Estrogênio/metabolismo , Estilbenos/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Masculino , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Neoplasias da Próstata/patologia , Ligação Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Resveratrol , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas
15.
Am J Physiol Renal Physiol ; 292(2): F828-36, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17077385

RESUMO

Epithelia can adjust the permeability of their paracellular permeation route to physiological requirements, pathological conditions, and pharmacological challenges. This is reflected by a transepithelial electrical resistance (TER) ranging from a few tenth to several thousands Omega.cm(2), depending on the degree of sealing of the tight junction (TJ). The present work is part of an effort to understand the causes and mechanisms underlying these adaptations. We observed that an extract of human urine (hDLU) increases TER in a concentration- and time-dependent manner and is more effective when added from the basolateral side of cultured monolayers of Madin-Darby canine kidney cells than from the apical one. We found that its main TER-increasing component is epidermal growth factor (hEGF), as depletion of this peptide with specific antibodies, or inhibition of its receptor with PD153035, abolishes its effect. Since the permeability of the TJ depends on the expression of several species of membrane proteins, chiefly claudins, we explored whether hDLU can affect five members of the claudin family, the three known members of the ZO family, and occludin. EGF present in hDLU decreases the content of claudins-1 and -2 as well as delocalizes them from the TJ and increases the content of claudin-4. As expected from the fact that the degree of sealing of the TJ must be a physiologically regulated parameter, besides of hEGF, we also found that hDLU appears to contain also other components that decrease TER, claudin-4 and -7, and that seem to act with different kinetics than the TER-increasing ones.


Assuntos
Fator de Crescimento Epidérmico/fisiologia , Junções Íntimas/fisiologia , Adolescente , Adulto , Animais , Permeabilidade da Membrana Celular/fisiologia , Células Cultivadas , Claudina-1 , Claudina-4 , Cães , Impedância Elétrica , Receptores ErbB/antagonistas & inibidores , Humanos , Masculino , Proteínas de Membrana/metabolismo , Quinazolinas/farmacologia
16.
Reprod Biomed Online ; 11(1): 58-63, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16102288

RESUMO

The main objective of this study was to evaluate the influence of the products secreted by the human embryo upon the three subtypes of beta-AR (beta1, beta2, beta3). Cell cultures were developed using endometrial biopsies, taken on day 7 after ovulation, from four healthy women <35 years of age, with regular cycles and infertility due only to male factors. Embryos from women with a normal uterine cavity and endometrial lining were incubated until they reached the 4-cell stage, before being transferred to their mother's uterus. Culture media for embryo incubation were derived from two groups: (i) embryos that achieved pregnancy, (ii) embryos which failed to implant. Control and experimental endometrial cell culture plates were treated with the two embryo culture media, with or without 10(-9) mol/l oestradiol and 10(-7) mol/l progesterone for 48 h. Expression of the three subtypes of beta-AR was assessed by RT-PCR. Beta1-AR was expressed in both control and experimental plates; beta2-AR was expressed only in plates incubated with embryonic culture media of embryos which achieved pregnancy, in both hormonal conditions, with or without oestradiol and progesterone. Beta3-AR was not expressed in any condition. Thus secretory products of human embryos may influence gene expression of beta2-AR concentrations in the human endometrium, and this subtype of beta-AR may be involved in implantation.


Assuntos
Meios de Cultivo Condicionados/farmacologia , Embrião de Mamíferos/citologia , Endométrio/metabolismo , Receptores Adrenérgicos beta/metabolismo , Adulto , Células Cultivadas , Técnicas de Cultura Embrionária , Implantação do Embrião , Endométrio/citologia , Endométrio/efeitos dos fármacos , Estradiol/farmacologia , Feminino , Humanos , Gravidez , Progesterona/farmacologia , Receptores Adrenérgicos beta/efeitos dos fármacos , Receptores Adrenérgicos beta/genética
17.
Rev Esp Med Nucl ; 23(5): 343-6, 2004.
Artigo em Espanhol | MEDLINE | ID: mdl-15450140

RESUMO

OBJECTIVE: Sulfur colloid 99mTc-SC, the radiopharmaceutical of choice for solid gastric emptying studies, is not available in our country. It has led us to assess the solid binding stability of seven alternative radiopharmaceuticals that could present adequate fixation to it a priori. MATERIALS AND METHOD: The stability of labelled solid food with seven colloidal 99mTc-radiopharmaceuticals of different sizes and nature (MAA, tin colloid, rhenium sulphide macrocolloid, albumin microcolloid, sulfur nanocolloid, albumin nanocolloid and rhenium sulfur nanocolloid) has been studied by measuring their dissociated activity after two hours digestion in simulated gastric fluid (kept 120' in agitation, in HCl 0.1 M at 37). The survey also assesses radiopharmaceutical labelling stability after two hours digestion in identical conditions by measuring their radiochemical purity in ITLC. RESULTS: In these conditions, MAA, rhenium sulphide macrocolloid, albumin microcolloid and albumin microcolloid present the best behaviour, with an activity linked to food over 90 % of the previously fixed activity. CONCLUSIONS: According to the results, there is no relationship between the radiopharmaceutical size and nature and the stability of its binding to the solid food. Because rhenium sulphide macrocolloid is no longer manufactured and the other three radiopharmaceuticals which have a binding stability to the solid food over 90 % do not include digestive explorations amongst their indications, nowadays, there is a serious legal limitation to carry out this type of studies in our country.


Assuntos
Ovos , Esvaziamento Gástrico , Compostos Radiofarmacêuticos/análise , Rênio/análise , Compostos de Tecnécio/análise , Agregado de Albumina Marcado com Tecnécio Tc 99m/análise , Coloide de Enxofre Marcado com Tecnécio Tc 99m/análise , Digestão , Estabilidade de Medicamentos , Temperatura Alta , Ácido Clorídrico/farmacologia , Técnicas In Vitro , Marcação por Isótopo , Tamanho da Partícula , Solubilidade , Solventes/farmacologia , Estresse Mecânico
18.
Tissue Antigens ; 64(2): 132-44, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15245368

RESUMO

The CD150 (SLAM) family consists of nine leukocyte cell-surface proteins involved in lymphocyte activation that belong to the immunoglobulin (Ig) superfamily. Six members of this family--CD84, CD150 (SLAM), CD229 (Ly9), CD244 (2B4), NTB-A, and CS1--associate with adapter proteins--SLAM-associated protein (SAP) and EAT-2. SAP is a short intracellular molecule that is mutated in humans with X-linked lymphoproliferative disease. Flow cytometric analysis of the expression of CD84, CD150, CD229, and CD244 cell-surface receptors on several leukocyte and lymphocyte subsets was performed. CD84 and CD150 were present on thymocytes, mature T cells and antigen-presenting cells. The expression of CD84 and CD150 was high on memory T cells. CD150 expression was strongly up-regulated after cell activation. In contrast to CD84, CD150 was absent on resting monocytes and immature dendritic cells (DCs). CD229 presented a pattern of expression restricted to lymphocytes. CD244 was preferentially expressed on natural killer cells, CD8(+) effector cells, resting monocytes, basophils, and eosinophils. We describe a broader distribution of CD84, CD150, CD229, and CD244 than previously reported and show that they are differentially expressed on hematopoietic cells. The heterogeneous expression of these receptors indicates that these molecules may play non-redundant functions in the regulation of both innate and adaptive immune responses.


Assuntos
Antígenos CD/metabolismo , Glicoproteínas/metabolismo , Imunoglobulinas/metabolismo , Leucócitos/imunologia , Glicoproteínas de Membrana/metabolismo , Receptores Imunológicos/metabolismo , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linhagem Celular , Células Dendríticas/imunologia , Células-Tronco Hematopoéticas/imunologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Ativação Linfocitária , Mastócitos/imunologia , Monócitos/imunologia , Tonsila Palatina/citologia , Receptores de Superfície Celular , Proteína Associada à Molécula de Sinalização da Ativação Linfocitária , Família de Moléculas de Sinalização da Ativação Linfocitária , Membro 1 da Família de Moléculas de Sinalização da Ativação Linfocitária , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Fatores de Transcrição/metabolismo
19.
J Membr Biol ; 198(3): 147-58, 2004 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15216416

RESUMO

Abstract. In previous work we described a "P-->A mechanism" that transduces occupancy of the pump ( P) by ouabain into changes in phosphorylation, stimulation of mitogen-activated protein kinase (MAPK), and endocytosis of cell-cell- and cell-substrate-attaching molecules ( A), thereby causing a release of the cell from the monolayer. In the present work we try to understand the mechanism of this effect; whether, in order to trigger the P-->A mechanism, ouabain should block the pumping activity of Na(+),K(+)-ATPase as pump, or whether it would suffice that the drug occupies this enzyme as a receptor. We assay a series of drugs known to act on the pump, such as ouabain, digoxin, digitoxin, palytoxin, oligomycin, strophanthidin, neothyoside-A, proscillaridin-A, etc. We gauge their ability to block the pump by measuring the K(+) content in the cells, and their ability to detach the cells from the monolayer by determining the amount of protein remaining in the culturing well. None of the drugs tested was able to cause detachment without stopping the pump. Ouabain also enhances phosphorylation, yet pump inhibition and signal transduction do not seem to be intimately associated in a causal chain, but to occur simultaneously. To investigate the response of the site of cell attachment, we analyze the position of beta-catenin by fluorescence confocal microscopy, and find that this adherent junction-associated molecule is sent to the nucleus, where it is known to act as a transcriptional cofactor.


Assuntos
Núcleo Celular/fisiologia , Proteínas do Citoesqueleto/metabolismo , Rim/fisiologia , Ouabaína/farmacologia , Transdução de Sinais/fisiologia , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , ATPase Trocadora de Sódio-Potássio/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Animais , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Cães , Ativação Enzimática/efeitos dos fármacos , Rim/citologia , Rim/efeitos dos fármacos , Ligação Proteica , Transdução de Sinais/efeitos dos fármacos , beta Catenina
20.
Cancer Immunol Immunother ; 53(7): 651-8, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-14999431

RESUMO

Eleven AJCC stage IV melanoma patients with progressive disease after treatment with biochemotherapy were treated with autologous dendritic cells pulsed with heterologous tumor cell lysates. The vaccine used mature DCs (CD1a+++, CD40++, CD80++, CD83+, and CD86+++) generated from peripheral blood monocytes in the presence of GM-CSF and IL-4. After 7 days, DCs were matured with a defined cocktail of cytokines (IL-1+IL-6+TNF-alpha+PGE2) and simultaneously pulsed with lysates of heterologous melanoma cell lines, for 2 days. A total of 4 x 10(6) DCs was injected monthly under ultrasound control in an inguinal lymph node of normal appearance. The study was closed when all patients died as a consequence of tumor progression. No sign of toxicity was observed during the study. One patient experienced a partial response lasting 5 months, and two patients showed a mixed response which lasted 3 months. The median survival of the whole group was 7.3 months (range 3-14 months). This vaccination program had specific antitumoral activity in highly pretreated and large tumor burden stage IV melanoma patients and was well tolerated. The clinical responses and the median survival of the group of patients, together with the low toxicity of our DC vaccine, suggest that this approach could be applied to earlier AJCC stage IV melanoma patients.


Assuntos
Vacinas Anticâncer/uso terapêutico , Células Dendríticas/imunologia , Imunoterapia , Melanoma/terapia , Neoplasias Cutâneas/terapia , Adulto , Antineoplásicos/uso terapêutico , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Humanos , Interferon gama/sangue , Interleucina-4/metabolismo , Masculino , Melanoma/imunologia , Melanoma/mortalidade , Melanoma/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Projetos Piloto , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Taxa de Sobrevida , Linfócitos T Citotóxicos/imunologia , Células Tumorais Cultivadas
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