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1.
Ginecol Obstet Mex ; 84(3): 172-9, 2016 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-27424443

RESUMO

BACKGROUND: The vulvar cancer is the fourth more frequent neoplasia after the endometrial, cervix and ovarian cancer. Normally, it has been related to old women of ages from 70 to 80 years old. Rarely, it has been detected cases in adult or young women. However, its incidence has been increased in the last years and in more early years. It is for this change in the incidence and its appearance in early years why a possible etiology has been looked for, opening different hypothesis that go from that related to the HPV to those that study an inflammatory chronic process as the basis for the carcinogenesis. CLINICAL CASE: In this article, it has been presented the case of a woman who is 34 years old with negative VPH that made her debut with epidermoid carcinoma of the vulva moderately different and on purpose of the case, we do a revision of the literature existent. CONCLUSIONS: Vulvar cancer diagnosed in young women as in older, but with different trends, risk factors and natural history. The case reported here escapes the theories studied so far so needed new lines of inquiry to investigate this form of presentation young woman, without HPV infection.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Vulvares , Adulto , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Infecções por Papillomavirus , Neoplasias Vulvares/patologia , Neoplasias Vulvares/cirurgia
2.
Lett Appl Microbiol ; 59(2): 127-32, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24785827

RESUMO

UNLABELLED: Bacterial comfort is central to biotechnological applications. Here, we report the characterization of different sensoring systems, the first step within a broader synthetic biology-inspired light-mediated strategy to determine Escherichia coli perception of environmental factors critical to bacterial performance. We did so by directly 'asking' bacterial cultures with light-encoded questions corresponding to the excitation wavelength of fluorescent proteins placed under the control of environment-sensitive promoters. We built four genetic constructions with fluorescent proteins responding to glucose, temperature, oxygen and nitrogen; and a fifth construction allowing UV-induced expression of heterologous genes. Our engineered strains proved able to give feedback in response to key environmental factors and to express heterologous proteins upon light induction. This light-based dialoguing strategy reported here is the first effort towards developing a human-bacteria interphase with both fundamental and applied implications. SIGNIFICANCE AND IMPACT OF THE STUDY: The results we present here are at the core of a larger synthetic biology research effort aiming at establishing a dialogue with bacteria. The framework is to convert the human voice into electric pulses, these into light pulses exciting bacterial fluorescent proteins, and convert light-emission back into electric pulses, which will be finally transformed into synthetic voice messages. We report here the first results of the project, in the form of light-based determination of key parameters for bacterial comfort. The ultimate goal of this strategy is to combine different engineered populations to have a combined feedback from the pool.


Assuntos
Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica/efeitos da radiação , Escherichia coli/metabolismo , Escherichia coli/efeitos da radiação , Interação Gene-Ambiente , Genes Bacterianos , Genes Reporter , Glucose/fisiologia , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Nitrogênio/fisiologia , Oxigênio/fisiologia , Regiões Promotoras Genéticas , Biologia Sintética , Ativação Transcricional/efeitos da radiação
3.
Neurobiol Dis ; 48(1): 79-91, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22677034

RESUMO

Parkinson's disease (PD) is diagnosed when striatal dopamine (DA) loss exceeds a certain threshold and the cardinal motor features become apparent. The presymptomatic compensatory mechanisms underlying the lack of motor manifestations despite progressive striatal depletion are not well understood. Most animal models of PD involve the induction of a severe dopaminergic deficit in an acute manner, which departs from the typical, chronic evolution of PD in humans. We have used 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) administered to monkeys via a slow intoxication protocol to produce a more gradual development of nigral lesion. Twelve control and 38 MPTP-intoxicated monkeys were divided into four groups. The latter included monkeys who were always asymptomatic, monkeys who recovered after showing mild parkinsonian signs, and monkeys with stable, moderate and severe parkinsonism. We found a close correlation between cell loss in the substantia nigra pars compacta (SNc) and striatal dopaminergic depletion and the four motor states. There was an overall negative correlation between the degree of parkinsonism (Kurlan scale) and in vivo PET ((18)F-DOPA K(i) and (11)C-DTBZ binding potential), as well as with TH-immunoreactive cell counts in SNc, striatal dopaminergic markers (TH, DAT and VMAT2) and striatal DA concentration. This intoxication protocol permits to establish a critical threshold of SNc cell loss and dopaminergic innervation distinguishing between the asymptomatic and symptomatic parkinsonian stages. Compensatory changes in nigrostriatal dopaminergic activity occurred in the recovered and parkinsonian monkeys when DA depletion was at least 88% of control, and accordingly may be considered too late to explain compensatory mechanisms in the early asymptomatic period. Our findings suggest the need for further exploration of the role of non-striatal mechanisms in PD prior to the development of motor features.


Assuntos
Corpo Estriado/metabolismo , Dopamina/metabolismo , Neurônios/metabolismo , Transtornos Parkinsonianos/metabolismo , Substância Negra/metabolismo , Animais , Comportamento Animal/fisiologia , Contagem de Células , Corpo Estriado/diagnóstico por imagem , Corpo Estriado/patologia , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Macaca fascicularis , Masculino , Atividade Motora/fisiologia , Neurônios/patologia , Transtornos Parkinsonianos/diagnóstico por imagem , Transtornos Parkinsonianos/patologia , Sintomas Prodrômicos , Cintilografia , Substância Negra/diagnóstico por imagem , Substância Negra/patologia , Tirosina 3-Mono-Oxigenase/metabolismo , Proteínas Vesiculares de Transporte de Monoamina/metabolismo
4.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32201272

RESUMO

OBJECTIVE: To optimize radiolabeling with 99mTc and 67Ga of albumin nanoparticles coated with 4 differents synthetic polymers and to evaluate their stability in vivo and in vitro, as well as their biodistribution in vivo after intravenous administration. MATERIAL AND METHODS: The nanoparticles were prepared using albumin and NOTA-modified albumin by the desolvation method and coated with 4 different polymers; HPMC, GMN2, GPM2 and GTM2. They were purified, lyophilized and characterized. Radiolabelling with 99mTc was perfomed with 74 MBq of 99mTc sodium pertechnetate, previously reduced with and acid solution of tin chloride at different concentrations (0.003, 0.005, 0.007, 0.01, 0.05 and 0.1mg/ml) and at different times (5, 10, 15, 30 and 60minutes) and temperatures (room temperature, 40°C and 60°C). Radiolabelling with 67Ga was perfomed by incubation of the nanoparticles with 37 MBq of 67Gallium chloride (obtained from commercial gallium-67 citrate) at different times (10 and 30minutes) and temperatures (room temperature, 30°C and 60°C), and posterior purification with microconcentrators. The radiochemical purity was evaluated by TLC. Stability studies of radiolabeled nanoparticles in physiological serum and blood plasma were perfomed. Biodistribution studies of nanoparticles coated with GPM2 polymer were carried out in Wistar rats after intravenous administration of the nanoparticles. Control animals were carried out with 99mTc sodium pertechnetate and 67Ga chloride. To do so, the animals were killed and activity in organs was measured in a gamma counter. RESULTS: 99mTc labeling was carried out optimally with a tin concentration of 0.007mg/ ml for the GPM2 nanoparticles and 0.005mg / ml for the rest of the formulations, with a radiolabelling time of 10minutes at room temperature. In the case of 67Ga the label was optimized at 30° C temperature and 30minutes of incubation. In both cases the radiochemical purity obtained was greater than 97%. The nanoparticles showed high stability in vitro after 48hours of labeling (70% nanoparticles labeled with 99mTc and 90% those labeled with 67Ga). Biodistribution studies of nanoparticles 99mTc -GPM2 and 67Ga -NOTA-GPM2 showed a high accumulation of activity in the liver at 2 and 24hours after intravenous administration. CONCLUSION: The labeling procedure with 99mTc and 67Ga of albumin and albumin modified with NOTA nanoparticles allows obtaining nanoparticles with high labeling yields and adequate in vitro stability, allowing their use for in vivo studies.


Assuntos
Radioisótopos de Gálio/farmacocinética , Gálio/farmacocinética , Marcação por Isótopo/métodos , Nanopartículas/administração & dosagem , Poliaminas/química , Compostos Radiofarmacêuticos/farmacocinética , Albumina Sérica Humana/farmacocinética , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tecnécio/farmacocinética , Tiamina/química , Animais , Cromatografia em Camada Fina , Estabilidade de Medicamentos , Feminino , Gálio/administração & dosagem , Gálio/análise , Radioisótopos de Gálio/administração & dosagem , Radioisótopos de Gálio/análise , Compostos Heterocíclicos com 1 Anel , Derivados da Hipromelose , Injeções Intravenosas , Nanopartículas/análise , Polietilenoglicóis , Compostos Radiofarmacêuticos/administração & dosagem , Compostos Radiofarmacêuticos/análise , Ratos , Ratos Wistar , Albumina Sérica Humana/administração & dosagem , Albumina Sérica Humana/análise , Tecnécio/administração & dosagem , Tecnécio/análise , Temperatura , Compostos de Estanho , Distribuição Tecidual
5.
Gene Ther ; 16(1): 136-41, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18668147

RESUMO

Non-invasive in vivo imaging of transgene expression is currently providing very important means to optimize gene therapy regimes. Results in non-human primates are considered the most predictive models for the outcome in patients. In this study, we have documented that tumour and primary cell lines from human and non-human primates are comparably gene-transduced in vitro by serotype 5 adenovirus expressing HSV1-thymidine kinase. Transgene expression can be quantified in human and monkey cultured cells by positron emission tomography (PET) imaging when transduced cells are incubated with a fluoride-18 labelled penciclovir analogue. In our hands, PET images of cell cultures estimate the number of transduced cells rather than intensity of transgene expression once a threshold of TK per cell is reached. Interestingly, in vivo systemic administration of a clinical grade recombinant adenovirus expressing TK into macaques gives rise to an intense retention of the radiotracer in the liver parenchyma, providing an experimental system to visualize transgene expression that ought to be similar in human and macaques. Such imaging methodology might contribute to improve strategies based on adenoviral vectors.


Assuntos
Terapia Genética/métodos , Herpesvirus Humano 1/enzimologia , Fígado/diagnóstico por imagem , Fígado/enzimologia , Tomografia por Emissão de Pósitrons , Timidina Quinase/genética , Aciclovir/análogos & derivados , Aciclovir/farmacologia , Adenoviridae/genética , Animais , Contagem de Células , Linhagem Celular Transformada , Expressão Gênica , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Guanina , Humanos , Injeções Intravenosas , Macaca , Modelos Animais , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/farmacologia , Transdução Genética/métodos , Transgenes
6.
Neuroimage ; 47(2): 533-9, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19422919

RESUMO

Normalization of neuroimaging studies to a stereotaxic space allows the utilization of standard volumes of interest (VOIs) and voxel-based analysis (SPM). Such spatial normalization of PET and MRI studies requires a high quality template image. The aim of this study was to create new MRI and PET templates of (18)F-DOPA and (11)C-(+)-alpha-dihydrotetrabenazine ((11)C-DTBZ) of the Macaca fascicularis brain, an important animal model of Parkinson's disease. MRI template was constructed as a smoothed average of the scans of 15 healthy animals, previously transformed into the space of one representative MRI. In order to create the PET templates, (18)F-DOPA and (11)C-DTBZ PET of the same subjects were acquired in a dedicated small animal PET scanner and transformed to the created MRI template space. To validate these templates for PET quantification, parametric values obtained with a standard VOI-map applied after spatial normalization to each template were statistically compared to results computed using individual VOIs drawn for each animal. The high correlation between both procedures validated the utilization of all the templates, improving the reproducibility of PET analysis. To prove the utility of the templates for voxel-based quantification, dopamine striatal depletion in a representative monkey treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was assessed by SPM analysis of (11)C-DTBZ PET. A symmetric reduction in striatal (11)C-DTBZ uptake was detected in accordance with the induced lesion. In conclusion, templates of M. fascicularis brain have been constructed and validated for reproducible and automated PET quantification. All templates are electronically available via the internet.


Assuntos
Encéfalo/anatomia & histologia , Encéfalo/diagnóstico por imagem , Di-Hidroxifenilalanina/análogos & derivados , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Tetrabenazina/análogos & derivados , Animais , Radioisótopos de Carbono , Macaca fascicularis , Compostos Radiofarmacêuticos , Valores de Referência , Técnica de Subtração
7.
Int J Pharm ; 569: 118484, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31260785

RESUMO

Re-activation of the healing process is a major challenge in the field of chronic wound treatment. For that purpose, lipid-nanoparticles, especially nanostructured lipid carriers (NLC), possess extremely useful characteristics such as biodegradability, biocompatibility and long-term stability, besides being suitable for drug delivery. Moreover, they maintain wound moisture due to their occlusive properties, which have been associated with increased healing rates. In the light of above, NLC have been extensively used topically for wound healing; but to date, there are no safety-preclinical studies concerning such type of application. Thus, in this work, biodistribution studies were performed in rats with the NLC previously developed by our research group, using technetium-99 m (99mTc-NLC) as radiomarker, topically administered on a wound. 99mTc-NLC remained on the wound for 24 h and systemic absorption was not observed after administration. In addition, toxicological studies were performed to assess NLC safety after topical administration. The results obtained demonstrated that NLC were non-cytotoxic, non-sensitizing and non-irritant/corrosive. Overall, it might be concluded that developed NLC remained at the administration area, potentially exerting a local effect, and were safe after topical administration on wounds.


Assuntos
Portadores de Fármacos/administração & dosagem , Lipídeos/administração & dosagem , Nanoestruturas/administração & dosagem , Animais , Células 3T3 BALB , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/toxicidade , Feminino , Lipídeos/farmacocinética , Lipídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos CBA , Nanoestruturas/toxicidade , Coelhos , Ratos Wistar , Pele/efeitos dos fármacos , Testes de Irritação da Pele , Tecnécio , Distribuição Tecidual , Cicatrização/efeitos dos fármacos
8.
Rev Esp Med Nucl ; 27(2): 103-11, 2008.
Artigo em Espanhol | MEDLINE | ID: mdl-18367048

RESUMO

AIM: This study evaluates the utility of (11)C-(+)-alpha -dihydrotetrabenazine ((11)C-(+)DTBZ) in the quantification of dopaminergic innervation by positron emission tomography (PET) in rat and monkey, two animal species used as animal models of Parkinson's disease. MATERIAL AND METHODS: Healthy control animals (n = 10) and the effect of 6-hydroxidopamine (6-OHDA) neurotoxic were studied in rats. (18)F-DOPA PET studies and digital quantitative autoradiography were also carried out. Studies with Macaca fascicularis were performed in control and 1-methyl 4-phenyl 1, 2, 3, 6-tetrahydropyridine (MPTP) treated animals. RESULTS: In both species high quality images were generated in which clear uptake of (11)C-(+)DTBZ was found in the striatum. (11)C-(+)DTBZ uptake quantification was estimated by creating parametric images and binding potential (BP) calculation. BP in control rats was 1.10 +/- 0.16 (mean +/- standard deviation [SD], whereas 6-OHDA produced a decrease in the uptake depending on the lesion degree. Images obtained with (18)F-DOPA were not adequate for the analysis as they did not discriminate the stratum whereas digital quantitative autoradiography studies confirmed the high affinity of striatum by (11)C-(+)DTBZ. In monkeys, final BP values were 1.31 and 1.06 and MPTP treatment reduced uptake by 40 %. CONCLUSIONS: The quality of PET images and the decrease of uptake in 6-OHDA and MPTP lesions show that (11)C-(+)DTBZ is an adequate radiotracer for the study of dopaminergic innervation in these animal models.


Assuntos
Doença de Parkinson/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Receptores Dopaminérgicos , Tetrabenazina/análogos & derivados , Animais , Macaca fascicularis , Masculino , Ratos
9.
Rev Esp Med Nucl ; 27(1): 13-21, 2008.
Artigo em Espanhol | MEDLINE | ID: mdl-18208777

RESUMO

UNLABELLED: Dihydrotetrabenazine (2-hydroxy-3-isobutyl-9,10-dimethoxy-1,3,4,6,7-hexahydro-11bH-benzo[a]-quinolizine, DTBZ) has become the ideal radioligand for the presynaptic vesicular monoamine transporter VMAT2 based on its high binding affinity and optimal lipophilicity. OBJECTIVE: To develop an automatic procedure for labelling DTBZ with carbon-11, which has been shown to be a highly effective marker for in vivo studies of neuronal losses in animal models with Parkinson's disease using positron emission tomography (PET). MATERIALS AND METHODS: We have developed a new fully automated synthesis procedure to obtain 11C-(+)DTBZ quickly and simply through labelling the precursor -(+)desmethyldihy-drotetrabenazine- at room temperature in the presence of dimethyl sulfoxide (DMSO) and potassium hydroxide (KOH), using 11CH3I as primary precursor. The final purification was carried out by solid phase extraction using commercially available cartridges and the residual solvents (DMSO and ethyl ether) were eliminated by evaporation. RESULTS: The whole procedure was automated, and after 54 syntheses, an average production of 1.94 GBq of sterile, pyrogen-free 11C-(+)DTBZ with a radiochemical purity > 99 % was obtained with 5 minutes irradiation and 6 minutes of synthesis after 11CH3I production. 11C-(+)DTBZ binding to presynaptic dopamine nerve terminals has been demonstrated by MicroPET studies in Wistar rats and M. Fascicularis monkeys. CONCLUSIONS: This new synthesis procedure is quick and simple, due to optimised techniques, which have allowed elimination of residual solvents based on their polarity for the final purification. It is also applicable to other automatic syntheses for obtaining compounds labelled by methylation reactions.


Assuntos
Radioisótopos de Carbono , Tomografia por Emissão de Pósitrons/métodos , Terminações Pré-Sinápticas/diagnóstico por imagem , Ensaio Radioligante , Compostos Radiofarmacêuticos/síntese química , Tetrabenazina/análogos & derivados , Proteínas Vesiculares de Transporte de Monoamina/análise , Automação , Cromatografia Líquida de Alta Pressão , Dimetil Sulfóxido , Dopamina , Contaminação de Medicamentos , Endotoxinas/análise , Éter , Humanos , Marcação por Isótopo/métodos , Terminações Pré-Sinápticas/química , Terminações Pré-Sinápticas/ultraestrutura , Controle de Qualidade , Receptores Pré-Sinápticos/química , Solventes , Tetrabenazina/síntese química
10.
Nuklearmedizin ; 46(4): 149-54, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17690793

RESUMO

UNLABELLED: Strategies to establish the functional benefit of cell therapy in cardiac regeneration and the potential mechanism are needed. AIMS: Development of a semi-quantitative method for non invasive assessment of cardiac viability and function in a rat model of myocardial infarction (MI) based on the use of microPET. ANIMALS, METHODS: Ten rats were subjected to myocardial imaging 2, 7, 14, 30, 60 and 90 days after left coronary artery ligation. Intravenous 18F-fluoro-2-deoxy-2-D-glucose (18F-FDG) was administered and regional 18F activity concentrations per unit area were measured in 17 regions of interest (ROIs) drawn on cardiac polar maps. By comparing the differences in 18F uptake between baseline and each of the follow up time points, parametric polar maps of statistical significance (PPMSS) were calculated. Left ventricular ejection fraction (LVEF) was blindly assessed echocardiographically. All animals were sacrificed for histopathological analysis after 90 days. RESULTS: The diagnostic quality of 18F-FDG microPET images was excellent. PPMSS demonstrated a statistically significant decrease in 18F concentrations as early as 48 hours after MI in 4 of the 17 ROIs (segments 7, 13, 16 and 17; p < 0.05) that persisted throughout the study. Semiquantitative analysis of 18F-FDG uptake correlated with echocardiographic decrease in LVEF (p < 0.001). CONCLUSION: The use of PPMSS based on 18F-FDG-microPET provides valuable semi-quantitative information of heart glucose metabolism allowing for non-invasive follow up thus representing a useful strategy for assessment of novel therapies in cardiac regeneration.


Assuntos
Fluordesoxiglucose F18/farmacocinética , Infarto do Miocárdio/diagnóstico por imagem , Compostos Radiofarmacêuticos/farmacocinética , Animais , Modelos Animais de Doenças , Ecocardiografia , Processamento de Imagem Assistida por Computador , Taxa de Depuração Metabólica , Cintilografia , Ratos , Ratos Sprague-Dawley
11.
EJNMMI Res ; 5(1): 70, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26635227

RESUMO

BACKGROUND: [(18)F]-tetrafluoroborate is a PET radiotracer taken up by the sodium/iodide symporter (NIS). Albeit the in vivo behavior in rodents is similar to the (99m)Tc-pertechnetate, no studies exist in primates or in humans. The aims of this study were to evaluate the biodistribution of [(18)F]-tetrafluoroborate in non-human primates with PET and to estimate the absorbed dose in organs. METHODS: Whole-body PET imaging was done in a Siemens ECAT HR+ scanner in two male Macaca fascicularis monkeys. After an i.v. injection of 24.93 ± 0.05 MBq/kg of [(18)F]-tetrafluoroborate, prepared by isotopic exchange of sodium tetrafluoroborate with [(18)F]-fluoride under acidic conditions, eight sequential images from the head to the thigh (five beds) were collected for a total duration of 132 min. The whole-body emission scan was reconstructed applying attenuation and scatter corrections. After image reconstruction, three-dimensional volumes of interest (VOIs) were hand-drawn on the PET transaxial or coronal slices of the frame where the organ was most conspicuous. Time-activity curves for each VOI were obtained, and the organ residence times were calculated by integration of the time-activity curves. Human absorbed doses were estimated using the OLINDA/EXM software and the standard human model. RESULTS: [(18)F]-tetrafluoroborate was able to discriminate clearly the thyroid gland with an excellent signal-to-noise ratio. Most of the radiotracers (residence time) are localised in the organs that express NIS (stomach wall, salivary glands, thyroid, olfactory mucosa), are involved in excretion (kidneys and bladder), or reflect the vascular phase (heart and lungs). Considering the OLINDA source organs, the critical organs were the stomach wall, thyroid and bladder wall, with absorbed doses lower than 0.078 mGy/MBq. The effective dose was 0.025 mSv/MBq. CONCLUSIONS: [(18)F]-tetrafluoroborate is a very useful radiotracer for PET thyroid imaging in primates, with a characteristic biodistribution in organs expressing NIS. It delivers an effective dose slightly higher than the dose produced by (99m)Tc-pertechnetate but much lower than that produced by radioiodine in the form of (131)INa, (123)INa, or (124)INa.

12.
J Photochem Photobiol B ; 70(3): 177-85, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12962642

RESUMO

The Antarctic ozone hole and a general depletion of the stratospheric ozone layer cause increased levels of ultraviolet-B solar radiation (UV-B) over Tierra del Fuego, the southernmost tip of South America. For three consecutive growing seasons (1997-2000), we studied the biological impacts (morphology, physiology, demography and phenology) of natural UV-B radiation on a perennial Salicornia ambigua Michx. community in San Sebastian Bay (53 degrees S and 68 degrees W), Tierra del Fuego, Argentina. This is the first UV-B screening experiment on a subantarctic halophytic community. The shortwave UV-B spectrum (280 to 320 nm) was excluded by covering plots with UV-B blocking film (Mylar). These plots were compared to controls covered with UV-B transparent (Aclar) plastic screens, and unscreened plots. Shoot length in Salicornia was not affected by UV-B. Exposure to natural UV-B reduced biomass and density (by 17% and 38%, respectively). Concentration of UV-shielding pigments and cuticle thickness were both significantly higher (25-48% and 21-40%, respectively) in plants receiving ambient UV-B. The increase in cuticle thickness persisted throughout the growing season, whereas pigment concentration was higher at the beginning of the growing season. Also, the number of dead shoots was higher in plants exposed to UV-B. At the end of the growing season (March) shoot mortality was higher in plants exposed to ambient UV-B, and post-flowering senescence was 30 days earlier. Slight changes in the relative composition of Salicornia to Puccinellia were seen. The reduction observed in Salicornia shoot density under ambient UV-B was cumulative over time; 23% in the first growing-season, rising to 38% by the third growing-season. A similar incremental increase in pigment absorption at 305 nm was seen; 25% in the first and 48% in the third growing season.


Assuntos
Chenopodiaceae/crescimento & desenvolvimento , Chenopodiaceae/efeitos da radiação , Raios Ultravioleta , Argentina , Biomassa , Estatura/efeitos da radiação , Peso Corporal/efeitos da radiação , Flores/efeitos da radiação , Fatores de Tempo
13.
Neotrop Entomol ; 42(1): 22-31, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23949709

RESUMO

Freshwater habitats are important elements within urban green space and they are endangered by various types of human activity. With the aim to increase the knowledge about species biodiversity in urban ecosystems, we characterised the assemblages of aquatic insects in four permanent man-made ponds in Buenos Aires city (Argentina) during a 1-year period. We recorded 32 species with Sigara spp. (Hemiptera) as the most abundant. The removal of aquatic vegetation from the studied ponds may have affected both the establishment and permanence of the insect community. Swimmers were the dominant group in the studied sites, followed by burrowers and sprawlers, and only a few strictly climbers were collected. Therefore, all sampled ponds were dominated by collectors (principally gatherers), secondarily by predators and only few shredders were detected, which was much affected by the removal of macrophytes. Non-parametric abundance indexes estimated a number of species very close to the observed number in each site. Conversely, the incidence indexes estimated more species because there were many more taxa present only in one sample than those represented by few individual in a sample. Our data provides some insights on the community of man-made ponds that can improve the management of these aquatic urban habitats. Considering that macrophytes affect animal assemblages due to their role as physical structures that increase the complexity or heterogeneity of habitats, they should not be removed by authorities in order to promote biodiversity.


Assuntos
Distribuição Animal , Insetos , Lagoas , Animais , Argentina , Comportamento Alimentar , Insetos/classificação
14.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 39(4): 225-232, jul.-ago. 2020. ilus, tab, graf
Artigo em Espanhol | IBECS (Espanha) | ID: ibc-198279

RESUMO

OBJETIVO: Optimizar el radiomarcaje con 99mTc y 67Ga de nanopartículas de albúmina recubiertas con 4 polímeros sintéticos distintos y evaluar su estabilidad in vivo e in vitro, así como su biodistribución in vivo tras su administración intravenosa. MATERIAL Y MÉTODOS: Las nanopartículas se prepararon empleando albúmina y albúmina modificada con NOTA mediante el método de desolvatación y se recubrieron con 4 polímeros distintos; HPMC, GMN2, GPM2 y GTM2. Se purificaron, liofilizaron y caracterizaron. El marcaje con 99mTc se realizó con 74MBq de pertecnetato [99mTc] sódico previamente reducido con una disolución ácida de cloruro de estaño a diferentes concentraciones (0,003; 0,005; 0,007; 0,01; 0,05 y 0,1mg/ml), a distintos tiempos (5, 10, 15, 30 y 60min) y temperaturas (temperatura ambiente, 40°C y 60°C). El marcaje con 67Ga se llevó a cabo mediante incubación de las nanopartículas con 37MBq de cloruro de 67Ga (obtenido a partir de citrato de 67Ga comercial) a distintos tiempos (10 y 30min) y temperaturas (temperatura ambiente, 30°C y 60°C) y posterior purificación con microconcentradores. La pureza radioquímica de ambos marcajes se evaluó mediante TLC. Se llevaron a cabo estudios de estabilidad de las nanopartículas marcadas en suero fisiológico y plasma sanguíneo. Los estudios de biodistribución de las nanopartículas recubiertas con el polímero GPM2 se llevaron a cabo en ratas Wistar tras la administración intravenosa de las nanopartículas. Se realizaron animales control con pertecnetato [99mTc] sódico y cloruro de 67Ga. Posteriormente, los animales fueron sacrificados y se midió la actividad de los órganos en un contador gamma. RESULTADOS: El marcaje con 99mTc se llevó a cabo de forma óptima con una concentración de estaño de 0,007mg/ml para las nanopartículas GPM2 y de 0,005mg/ml para el resto de formulaciones, con un tiempo de marcaje de 10min y a temperatura ambiente. En el caso del 67Ga el marcaje se optimizó a 30°C de temperatura y 30min de incubación. En ambos casos, la pureza radioquímica obtenida fue superior al 97%. Las nanopartículas presentaron una elevada estabilidad in vitro pasadas las 48h del marcaje (70% las nanopartículas marcadas con 99mTc y 90% las marcadas con 67Ga). Los estudios de biodistribución de las nanopartículas [99mTc]-GPM2 y [67Ga]-NOTA-GPM2 mostraron una elevada acumulación de actividad en el hígado tanto a las 2h como a las 24h de la administración intravenosa. CONCLUSIÓN: El procedimiento de marcaje con 99mTc y 67Ga de nanopartículas de albúmina y albúmina modificada con NOTA permite la obtención de nanopartículas con elevados rendimientos de marcaje y una adecuada estabilidad in vitro, permitiendo su utilización para la realización de estudios in vivo


OBJECTIVE: To optimize radiolabeling with 99mTc and 67Ga of albumin nanoparticles coated with 4 differents synthetic polymers and to evaluate their stability in vivo and in vitro, as well as their biodistribution in vivo after intravenous administration. MATERIAL AND METHODS: The nanoparticles were prepared using albumin and NOTA-modified albumin by the desolvation method and coated with 4 different polymers; HPMC, GMN2, GPM2 and GTM2. They were purified, lyophilized and characterized. Radiolabelling with 99mTc was perfomed with 74 MBq of 99mTc sodium pertechnetate, previously reduced with and acid solution of tin chloride at different concentrations (0.003, 0.005, 0.007, 0.01, 0.05 and 0.1mg/ml) and at different times (5, 10, 15, 30 and 60minutes) and temperatures (room temperature, 40°C and 60°C). Radiolabelling with 67Ga was perfomed by incubation of the nanoparticles with 37 MBq of 67Gallium chloride (obtained from commercial gallium-67 citrate) at different times (10 and 30minutes) and temperatures (room temperature, 30°C and 60°C), and posterior purification with microconcentrators. The radiochemical purity was evaluated by TLC. Stability studies of radiolabeled nanoparticles in physiological serum and blood plasma were perfomed. Biodistribution studies of nanoparticles coated with GPM2 polymer were carried out in Wistar rats after intravenous administration of the nanoparticles. Control animals were carried out with 99mTc sodium pertechnetate and 67Ga chloride. To do so, the animals were killed and activity in organs was measured in a gamma counter. RESULTS: 99mTc labeling was carried out optimally with a tin concentration of 0.007mg/ ml for the GPM2 nanoparticles and 0.005mg / ml for the rest of the formulations, with a radiolabelling time of 10minutes at room temperature. In the case of 67Ga the label was optimized at 30° C temperature and 30minutes of incubation. In both cases the radiochemical purity obtained was greater than 97%. The nanoparticles showed high stability in vitro after 48hours of labeling (70% nanoparticles labeled with 99mTc and 90% those labeled with 67Ga). Biodistribution studies of nanoparticles 99mTc -GPM2 and 67Ga -NOTA-GPM2 showed a high accumulation of activity in the liver at 2 and 24hours after intravenous administration. CONCLUSION: The labeling procedure with 99mTc and 67Ga of albumin and albumin modified with NOTA nanoparticles allows obtaining nanoparticles with high labeling yields and adequate in vitro stability, allowing their use for in vivo studies


Assuntos
Animais , Marcação por Isótopo/métodos , Nanopartículas/administração & dosagem , Tecnécio/administração & dosagem , Radioisótopos de Gálio/administração & dosagem , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único/métodos , Agregado de Albumina Marcado com Tecnécio Tc 99m/farmacologia , Isótopos de Gálio/administração & dosagem , Modelos Animais de Doenças , Ratos Wistar
16.
Gen Comp Endocrinol ; 133(1): 50-60, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12899846

RESUMO

Adrenomedullin (AM) and proadrenomedullin N-terminal 20 peptide (PAMP) are two multifunctional peptides processed from a common precursor which have been described in numerous mammalian organs, including the pituitary gland. Previous studies have found AM immunoreactivity in neurohypophysis nerve fibers of amphibian pituitary. In the present study, immunocytochemical and Western blot analysis in the pituitary gland of the amphibian Rana perezi demonstrated in the adenohypophysis both AM and PAMP. AM-like immunoreactivity was found in a moderate number of endocrine cells of the pars distalis. In the neurohypophysis, AM was observed not only in nerve fibers of pars nervosa and axonal projections innervating the pars intermedia, but also in the outer zone of the median eminence. PAMP staining was observed in numerous endocrine cells scattered all over the pars distalis and in some cells of the pars tuberalis, but not in the neurohypophysis. In order to compare the quantity of AM and PAMP immunoreactivity between pars distalis of female and male specimens, an image analysis study was done. Significant differences for AM immunoreactivity (p<0.001) between sexes was found, the males showing higher immunostained area percentage. Differences of PAMP immunoreactivity were not significant (p=0.599). Western blot analysis detected bands presumably corresponding to precursor and/or intermediate species in the propeptide processing.


Assuntos
Fragmentos de Peptídeos/metabolismo , Peptídeos/metabolismo , Hipófise/metabolismo , Precursores de Proteínas/metabolismo , Proteínas/metabolismo , Ranidae/metabolismo , Adrenomedulina , Animais , Western Blotting , Feminino , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Masculino , Distribuição Tecidual
17.
Gerokomos (Madr., Ed. impr.) ; 19(1): 47-52, mar. 2008. ilus, tab
Artigo em Es | IBECS (Espanha) | ID: ibc-66649

RESUMO

En la actualidad y en nuestro medio, las quemaduras domésticas sonuna de las lesiones más habituales, y en las que mejor podemos iniciarun programa de prevención progresivo. Las más comunes son las escaldaduras–debido al contacto accidental con líquidos o gases calientes– ylas producidas por la acción directa de las llamas. Las consecuencias vandesde el dolor, la deshidratación, las secuelas físicas con repercusionespsíquicas hasta, en ocasiones, la muerte. Ante un paciente con quemadurases prioritario y esencial llevar a cabo una minuciosa y adecuadavaloración inicial que incluya: grado de la lesión (profundidad), extensión(porcentaje de superficie corporal total quemada), zona anatómicaafectada y estado general del paciente (edad, estado inmunológico,nutricional, respiratorio, circulatorio, etc.), para así poder planificar loscuidados adecuados. En el presente trabajo describimos el caso de unamujer de 62 años que sufre quemaduras de primer grado y segundogrado superficial y profundo en cuello, ambas mamas y abdomen mientrasmanipulaba una olla a presión, con una extensión de un 6% de SCTA (Superficie Corporal Total Afectada). Se expone todo el procesode valoración de la paciente y su correspondiente plan de cuidados,detallando los distintos tratamientos locales en función de la evoluciónde las lesiones, así como las medidas preventivas para minimizar lasposibles complicaciones físicas y psíquicas derivadas de la aparición decicatrices hipertróficas


Actually, in our environment, domestic burns are one of the more frequent lesions,and we can start a progressive prevention program in a better way on these ones.The more common of them are scalds -due to an accidental contact with hot liquidsor gas- and those ones produced because of the direct action of flames. The consequencesgo from pain, dehydration, physical sequels with psychical repercussions to,sometimes, death. In the presence of a patient with burns is essential and a priorityto perform a comprehensive and appropriate first assessment that includes: degree oflesion (depth), extension (percentage of total burned body surface), anatomical areaaffected and the patient general condition (age, immunological, nutritional, respiratoryand circulatory status, etc.), in order to plan the appropriate care. In the presentwork, we describe the case of a 62-years-old woman who suffered first degreeand second degree burns, superficial and deep, in neck, breast and abdomen whenshe was handling a pressure cooker, with an extension of 6% BBS (Burned BodySurface). Here we expose all the assessment process of the patient and the correspondingcare plan, giving details of the different local treatments depending on the evolutionof lesions, just as the prevention measures for minimizing the potentialpsychical and physical complications stemmed from the arising of hypertrophic scars


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Acidentes Domésticos , Queimaduras/complicações , Queimaduras/terapia , Cicatriz Hipertrófica/etiologia , Cicatriz Hipertrófica/prevenção & controle , Índice de Gravidade de Doença , Protocolos Clínicos
18.
Rev. Asoc. Esp. Espec. Med. Trab ; 17(1): 30-35, abr. 2008. tab
Artigo em Espanhol | IBECS (Espanha) | ID: ibc-89173

RESUMO

La osteoporosis es una de las enfermedades que han aumentado su prevalencia en los últimos años debido al aumento de la esperanza de vida. Su prevención se puede realizar desde la edad media de la vida realizando un diagnóstico precoz y modificando estilos de vida. Objetivo: Conocer la prevalencia de la osteoporosis entre los trabajadores de una empresa de administración local. Metodología: Estudio transversal descriptivo de prevalencia de enfermedad. En una empresa de 1.500 trabajadores se realizó, de forma voluntaria, una densitometría ósea ultrasónica. Se analizaron las siguientes variables: edad, sexo, peso, talla, IMC, BUA (broadband ultrasound attenuation), porcentaje en comparación con la población normal, Z-score, T-score. Los cálculos estadísticos se analizaron con el programa Statgraphics Plus. Resultados: La prevalencia de la osteoporosis fue del 21,83%, con un claro predominio en el sexo masculino (42,5%) y con un 17,46% en mujeres. Conclusiones: Alta prevalencia de la osteoporosis entre la población masculina estudiada (AU)


Background: Osteoporosis ranks among the diseases having increased their prevalence over the last years because of the increase in life expectancy. Prevention can be achieved as from the middle ages of life through early diagnosis and lifestyle modifications. Objective: To assess the prevalence of osteoporosis among workers of a local management enterprise. Methods: Cross-sectional, descriptive, disease-prevalence study. Within a company encompassing 1,500 workers, volunteer ultrasound bone densitometry assessments were performed. The following variables were analyzed: age, gender, weight, height, BMI, BUA (broad-band ultrasound attenuation), proportion (%) to the normal population, Z-score and T-score. The Statgraphics Plus software was used for the statistical calculations.Results: The overall prevalence of osteoporosis was 21.83%, with a clear predominance of the male gender (42.5% vs. 17.46% in females). Conclusions: There was a high prevalence of osteoporosis among the males in the studied population (AU)


Assuntos
Humanos , Masculino , Feminino , Osteoporose/epidemiologia , Calcâneo/fisiopatologia , Densitometria/métodos , Osteoporose , 16054 , Estudos Transversais , Desmineralização Patológica Óssea , Fatores de Risco
19.
Rev. esp. med. nucl. (Ed. impr.) ; 27(1): 13-21, ene. 2008. ilus
Artigo em Es | IBECS (Espanha) | ID: ibc-058579

RESUMO

La dihidrotetrabenazina (2-hidroxi-3-isobutil-9,10-dimetoxi-1,3,4,6,7-hexahidro-11bH-benzo[a]-quinolizina, DTBZ) se ha convertido en el ligando ideal de los transportadores presinápticos de monoaminas (VMAT2) debido a su elevada afinidad de unión y su lipofilicidad. Objetivo. Desarrollar un procedimiento de síntesis automático para el marcaje con carbono-11 de la DTBZ para utilizarla como marcador en el estudio in vivo mediante tomografía por emisión de positrones de pérdidas neuronales en modelos animales de enfermedad de Parkinson. Material y métodos. Se ha diseñado un nuevo método de síntesis totalmente automatizado para la obtención de 11C-(+)DTBZ. La reacción de metilación del precursor ­(+)desmetildihidrotetrabenazina­ se lleva a cabo a temperatura ambiente, a partir de la obtención de 11CH3I que utilizamos como precursor primario, en presencia de dimetilsulfóxido e hidróxido de potasio. Para los procesos de purificación se han utilizado cartuchos de extracción en fase sólida alúmina y los disolventes residuales del producto final se eliminaron mediante evaporación bajo flujo de helio. Resultados. De las 54 síntesis realizadas se han obtenido, con un tiempo de bombardeo de 5 minutos, y 6 minutos de síntesis tras la obtención de 11CH3I, unas producciones medias de 1,94 ± 0,13 GBq de 11C-(+)DTBZ, estéril, apirógeno y con una pureza radioquímica > 99 %. Conclusiones. Este nuevo procedimiento de síntesis es rápido y simple, ya que para la purificación final se han optimizado técnicas que permitieran la eliminación de los disolventes residuales basándonos en su polaridad y es aplicable a otras síntesis automáticas para la obtención de otros compuestos marcados mediante reacciones de metilación


Dihydrotetrabenazine (2-hydroxy-3-isobutyl-9,10-dimethoxy-1,3,4,6,7-hexahydro-11bH-benzo[a]-quinolizine, DTBZ) has become the ideal radioligand for the presynaptic vesicular monoamine transporter VMAT2 based on its high binding affinity and optimal lipophilicity. Objective. To develop an automatic procedure for labelling DTBZ with carbon-11, which has been shown to be a highly effective marker for in vivo studies of neuronal losses in animal models with Parkinson's disease using positron emission tomography (PET). Materials and methods. We have developed a new fully automated synthesis procedure to obtain 11C-(+)DTBZ quickly and simply through labelling the precursor ­(+)desmethyldihydrotetrabenazine­ at room temperature in the presence of dimethyl sulfoxide (DMSO) and potassium hydroxide (KOH), using 11CH3I as primary precursor. The final purification was carried out by solid phase extraction using commercially available cartridges and the residual solvents (DMSO and ethyl ether) were eliminated by evaporation. Results. The whole procedure was automated, and after 54 syntheses, an average production of 1.94 GBq of sterile, pyrogen-free 11C-(+)DTBZ with a radiochemical purity > 99 % was obtained with 5 minutes irradiation and 6 minutes of synthesis after 11CH3I production. 11C-(+)DTBZ binding to presynaptic dopamine nerve terminals has been demonstrated by MicroPET studies in Wistar rats and M. Fascicularis monkeys. Conclusions. This new synthesis procedure is quick and simple, due to optimised techniques, which have allowed elimination of residual solvents based on their polarity for the final purification. It is also applicable to other automatic syntheses for obtaining compounds labelled by methylation reactions


Assuntos
Humanos , Tomografia Computadorizada de Emissão/métodos , Proteínas de Ligação a DNA/análise , Tetrabenazina , Biossíntese Peptídica
20.
Rev. esp. med. nucl. (Ed. impr.) ; 27(2): 103-111, mar.2008. ilus
Artigo em Es | IBECS (Espanha) | ID: ibc-66006

RESUMO

Objetivo. Este trabajo evalúa la idoneidad del radiotrazador 11C-(+)-α -dihidrotetrabenazina (11C-(+)DTBZ) para cuantificar mediante tomografía de emisión de positrones (PET) la inervación dopaminérgica en rata y mono, especies utilizadas como modelos animales en el estudio de la enfermedad de Parkinson. Material y métodos. En ratas se estudió una población control sana (n = 10) y el efecto del neurotóxico 6-hidroxidopamina (6-OHDA), además de realizarse estudios PET con 6-[(18)F]-fluoro-L-DOPA (18F-DOPA) y de autorradiografía digital cuantitativa. El estudio en Macaca fascicularis se realizó en animales control y tratados con el tóxico 1-metil-4-fenil-1,2,3,6-tetrahidropiridina (MPTP). Resultados. En ambas especies se obtuvieron imágenes de gran calidad donde se observó una alta captación de 11C-(+) DTBZ en el estriado. La cuantificación se realizó mediante la creación de imágenes paramétricas y el cálculo del potencial de unión (BP). La medida del BP en la población control de ratas arrojó un valor de 1,10 ± 0,16 (media ± error estándar [EE]), mientras que los estriados dañados con 6-OHDA mostraron una captación disminuida en función del grado de la lesión. Las imágenes obtenidas con 18F-DOPA no fueron aptas para el análisis al no discriminar los estriados, mientras que el estudio mediante autorradiografía digital cuantitativa confirmó la elevada afinidad de la 11C-(+)DTBZ por estas estructuras. En monos, el valor final de BP fue de 1,31 y 1,06 mientras que el tratamiento con MPTP disminuyó la captación en un 40 %. Conclusiones. La calidad de las imágenes PET y la disminución de la captación en las lesiones con 6-OHDA y MPTP indican que la 11C-(+)DTBZ es un radiotrazador adecuado para el estudio de la inervación dopaminérgica en estas especies animales


Aim. This study evaluates the utility of 11C-(+)-α -dihydrotetrabenazine (11C-(+)DTBZ) in the quantification of dopaminergic innervation by positron emission tomography (PET) in rat and monkey, two animal species used as animal models of Parkinson's disease. Material and methods. Healthy control animals (n = 10) and the effect of 6-hydroxidopamine (6-OHDA) neurotoxic were studied in rats. 18F-DOPA PET studies and digital quantitative autoradiography were also carried out. Studies with Macaca fascicularis were performed in control and 1-methyl 4-phenyl 1, 2, 3, 6-tetrahydropyridine (MPTP) treated animals. Results. In both species high quality images were generated in which clear uptake of 11C-(+)DTBZ was found in the striatum. 11C-(+)DTBZ uptake quantification was estimated by creating parametric images and binding potential (BP) calculation. BP in control rats was 1.10 ± 0.16 (mean ± standard deviation [SD], whereas 6-OHDA produced a decrease in the uptake depending on the lesion degree. Images obtained with 18F-DOPA were not adequate for the analysis as they did not discriminate the stratum whereas digital quantitative autoradiography studies confirmed the high affinity of striatum by 11C-(+)DTBZ. In monkeys, final BP values were 1.31 and 1.06 and MPTP treatment reduced uptake by 40 %. Conclusions. The quality of PET images and the decrease of uptake in 6-OHDA and MPTP lesions show that 11C-(+)DTBZ is an adequate radiotracer for the study of dopaminergic innervation in these animal models


Assuntos
Animais , Doença de Parkinson/diagnóstico , Tetrabenazina , Tomografia Computadorizada de Emissão/métodos , Modelos Animais de Doenças , Traçadores Radioativos , Intensificação de Imagem Radiográfica/métodos
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