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1.
Environ Res ; 247: 118120, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38199476

RESUMO

Photo-catalysts based on BiVO4 (BV) and Eco-graphene (EG) were synthesized and obtained in a single step with high-quality properties. These nanostructures (NEs) were obtained through a green chemistry route and by adding 2, 3, and 5 wt% of a homemade EG. The BV/X EG NEs (where X = corresponds to the weight % of EG) demonstrated high photocatalytic activity, obtaining Sulfamethoxazole degradation percentages of 40, 45, 52, and 57 for BV, BV/2 EG, BV/3 EG, and BV/5 EG respectively, using a blue LED light. In addition, it was observed that the presence of EG slightly affected the surface area and porosity of BV. Moreover, it was observed that the presence of EG stabilized the scheelite monoclinic phase (m-s), and decreased the crystal size and band-gap values of BV-based samples. It was detected that EG contents increased the BV reduction, creating oxygen vacancies and V4+ states, which favored electron transfer, enhanced the photo-catalytic activity, and decreased the recombination rate. The adsorption influence of the BV/EG system was also studied. Finally, the stability tests of these materials after four cycles of reuse allowed keeping practically the full degradation capacity, demonstrating that these NEs represent a promising material driven by visible light that can be used for wastewater decontamination in the presence of drugs.


Assuntos
Grafite , Nanoestruturas , Grafite/química , Sulfametoxazol , Adsorção , Luz
2.
Environ Res ; 228: 115757, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36967002

RESUMO

Fe-doped carbon xerogels with a highly developed graphitic structure were synthesized by a one-step sol-gel polymerization. These highly graphitic Fe-doped carbons are presented as promising dual-functional electro-Fenton catalysts to perform both the electro-reduction of O2 to H2O2 and H2O2 catalytic decomposition (Fenton) for wastewater decontamination. The amount of Fe is key to the development of this electrode material, since affects the textural properties; catalyzes the development of graphitic clusters improving the electrode conductivity; and influences the O2-catalyst interaction controlling the H2O2 selectivity but, at the same time is the catalyst for the decomposition of the electrogenerated H2O2 to OH• radicals for the organic pollutants oxidation. All materials achieve the development of ORR via the 2-electron route. The presence of Fe considerably improves the electro-catalytic activity. However, a mechanism change seems to occur at around -0.5 V in highly Fe-doped samples. At potential lower than -0.5 eV, the present of Feδ+ species or even Fe-O-C active sites favour the selectivity to 2e-pathway, however at higher potentials, Feδ+ species are reduced favoring a O-O strong interaction enhancing the 4e-pathway. The Electro-Fenton degradation of tetracycline was analyzed. The TTC degradation is almost complete (95.13%) after 7 h of reaction without using any external Fenton-catalysts.


Assuntos
Grafite , Poluentes Químicos da Água , Carbono , Águas Residuárias , Peróxido de Hidrogênio/química , Poluentes Químicos da Água/análise , Tetraciclina , Antibacterianos , Oxirredução
3.
J Appl Microbiol ; 120(3): 724-39, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26671760

RESUMO

AIMS: To search for culturable Burkholderia species associated with annual ryegrass in soils from natural pastures in Portugal, with plant growth-promoting effects. METHODS AND RESULTS: Annual ryegrass seedlings were used to trap Burkholderia from two different soils in laboratory conditions. A combined approach using genomic fingerprinting and sequencing of 16S rRNA and recA genes resulted in the identification of Burkholderia strains belonging to the species Burkholderia graminis, Burkholderia fungorum and the Burkholderia cepacia complex. Most strains were able to solubilize mineral phosphate and to synthesize indole acetic acid; some of them could produce siderophores and antagonize the phytopathogenic oomycete, Phytophthora cinnamomi. A strain (G2Bd5) of B. graminis was selected for gnotobiotic plant inoculation experiments. The main effects were the stimulation of root growth and enhancement of leaf lipid synthesis and turnover. Fluorescence in situ hybridization and confocal laser microscopy evidenced that strain G2Bd5 is a rhizospheric and endophytic colonizer of annual ryegrass. CONCLUSIONS: This work revealed that annual ryegrass can naturally associate with members of the genus Burkholderia. A novel plant growth promoting strain of B. graminis was obtained. SIGNIFICANCE AND IMPACT OF THE STUDY: The novel strain belongs to the plant-associated Burkholderia cluster and is a promising candidate for exploitation as plant inoculant in field conditions.


Assuntos
Burkholderia/isolamento & purificação , Lolium/microbiologia , Microbiologia do Solo , Burkholderia/classificação , Burkholderia/genética , Burkholderia/metabolismo , Ácidos Indolacéticos/metabolismo , Lolium/crescimento & desenvolvimento , Dados de Sequência Molecular , Fosfatos/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Portugal , RNA Ribossômico 16S/genética , Solo/química
4.
Clin Oral Investig ; 20(7): 1639-45, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26578117

RESUMO

INTRODUCTION: An ideal pulpotomy agent for primary molars has been sought for many years. Recently, new materials that allow regeneration of residual pulp tissue have been developed. In this study, we compared the preliminary clinical results obtained using Biodentine and mineral trioxide aggregate (MTA) as pulp-dressing agents in pulpotomies of primary molars. METHODS: A randomized clinical study was performed in children aged 4-9 years with at least one primary tooth with decay or caries requiring pulp treatment. A total of 90 primary molars requiring pulpotomy were randomly allocated to the MTA or Biodentine group, and 84 pulpotomies were performed. Clinical and radiographic evaluations were undertaken 6 and 12 months after treatment. All teeth were restored with a reinforced zinc oxide-eugenol base and stainless steel crowns. Statistical analysis using Fisher's exact test was performed to determine the significant differences between the groups. RESULTS: A total of four clinical failures were observed; all involved gingival inflammation. The clinical success rate in the MTA Group after 12 months was 92 % (36/39), whereas the Biodentine Group obtained 97 % (38/39) (p = 0.346). All radiographic failures were observed at the 12-month follow-up evaluation. One molar from MTA Group showed internal resorption obtaining a radiographic success rate of 97 % (38/39). Two molars from the Biodentine Group showed radiographic failure (1 internal resorption and 1 periradicular radiolucency) obtaining a radiographic success rate of 95 % (37/39). CONCLUSIONS: Biodentine showed similar clinical results as MTA with comparable success rates when used for pulpotomies of primary molars. However, longer follow-up studies are required to confirm our findings. CLINICAL RELEVANCE: This article demonstrates the effectiveness of Biodentine as a primary teeth pulpotomy material, performing similar results as MTA at 12-months evaluation.


Assuntos
Compostos de Alumínio/uso terapêutico , Compostos de Cálcio/uso terapêutico , Dente Molar/cirurgia , Óxidos/uso terapêutico , Agentes de Capeamento da Polpa Dentária e Pulpectomia/uso terapêutico , Pulpotomia/métodos , Silicatos/uso terapêutico , Criança , Pré-Escolar , Coroas , Forramento da Cavidade Dentária , Combinação de Medicamentos , Eugenol , Feminino , Humanos , Masculino , Dente Decíduo , Resultado do Tratamento , Óxido de Zinco
5.
Eur J Paediatr Dent ; 15(2 Suppl): 229-33, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25101510

RESUMO

BACKGROUND: Young patients with early childhood caries (ECC) commonly undergo oral rehabilitation under general anaesthesia (GA), often because of problems with behaviour management. Children with a history of ECC are highly susceptible to the development of new caries, even after comprehensive oral rehabilitation. CASE REPORT: The present paper reports the case of a female patient, aged 4.1 years, with ECC who was referred for treatment to the Department of Paediatric Dentistry of the Universitat Internacional de Catalunya. On account of the requirement for extensive dental treatment, and because of behaviour management problems, her dentition was restored under GA. A combination of restorative approaches and techniques was used, including the placement of composite resins, preformed metal crown restorations, extractions, and space maintainers. The patient was followed for 24 months, both clinically and radiographically. Conclusion This case reflects the need to provide adequate support to children at high risk for ECC, together with their families by developing more acceptable and effective biological and behavioural interventions in order to reduce caries relapse after oral rehabilitation under GA.


Assuntos
Anestesia Geral , Cárie Dentária/terapia , Boca/fisiopatologia , Pré-Escolar , Cárie Dentária/fisiopatologia , Cárie Dentária/reabilitação , Prótese Dentária , Feminino , Humanos
6.
Eur J Paediatr Dent ; 15(3): 297-302, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25306148

RESUMO

AIM: To evaluate whether the parental perception of the patient's anxiety, children's anxiety, pain, behaviour and heart rate of paediatric patients improves when an audiovisual technique is used as a distraction method during dental treatment. MATERIALS AND METHODS: This non-randomised crossover trial was performed with 34 patients aged 6-8 years, who required a minimum of two treatment visits for restorative therapy. During the last visit, the patient was shown a cartoon film. RESULTS: There was a significant improvement in the global behaviour when children were shown a cartoon film (P < 0.001). A significant increase in heart rate was recorded in both visits (P = 0.0001) when the anaesthetic was injected. A 97% of the sample would like to continue seeing their chosen film during subsequent visits. No statistically significant differences were found (P > 0.05) between the visits in terms of parental perception of the patient's anxiety, or the patient's self-reported anxiety, pain and heart rate. CONCLUSIONS: The use of the audiovisual material used as a method of distraction produces a global improvement in patient behaviour, but not in parental perception of the patient's anxiety, self-reported anxiety, pain or heart rate according to the measurement scales used. This material is also highly accepted by paediatric patients.


Assuntos
Atenção , Recursos Audiovisuais , Comportamento Infantil , Ansiedade ao Tratamento Odontológico/psicologia , Dor/psicologia , Desenhos Animados como Assunto , Criança , Comportamento Cooperativo , Estudos Cross-Over , Ansiedade ao Tratamento Odontológico/classificação , Assistência Odontológica/psicologia , Relações Dentista-Paciente , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Dor/classificação , Relações Pais-Filho , Autorrelato , Escala Visual Analógica
7.
Eur J Paediatr Dent ; 12(4): 239-44, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22185248

RESUMO

AIM: Anxiety has been defined as a nonspecific feeling of apprehension towards a concrete situation that does not necessarily involve a previous experience. Dental anxiety can prevent patients from cooperating fully during dental treatment. Given that there is a connection between dental anxiety and uncooperative behaviour, it is important for dentists to be able to assess anxiety in their patients. There are many methods for such assessment, and in children they depend on age and intellectual development. These measures can be objective or subjective, depending on the method used to quantify the degree of anxiety. The aim of this literature review was to analyse the objective and subjective scales that are used most commonly to assess the degree of anxiety of children in a dental setting. CONCLUSION: Knowing the degree of anxiety of dental children is important in order to guide them through their dental experience. Their level of cooperation will also improve and anxiety will be reduced as well.


Assuntos
Ansiedade ao Tratamento Odontológico/diagnóstico , Pressão Sanguínea , Criança , Resposta Galvânica da Pele , Frequência Cardíaca , Humanos , Hidrocortisona/análise , Hidrocortisona/metabolismo , Escala de Ansiedade Manifesta , Modelos Psicológicos , Saliva/química
8.
Acta Ortop Mex ; 32(5): 291-296, 2018.
Artigo em Espanhol | MEDLINE | ID: mdl-30726592

RESUMO

INTRODUCTION: Pycnodysostosis is a rare disease secondary to a mutation in gen 1q21 that codifies the cathepsin K, proteolitic enzyme implicated in the metabolism of osteonectin, osteopontin and type I colagen. Its global incidence is around 1-1.7 cases per million, without genre prevalences, it is clinically caracterized by short stature, craneal deformities, «birds face¼ and bone fragility with pathological fractures tendency predominantly affecting long bones and occasionally vertebral pedicles. Radiologically is characterized by sclerous bones with permeable medular cannel. Despite there are numerous clinical reports on medical literature, just a litlle describe families with more than one afected member and its followship is usually short-term. OBJECTIVE: To analize clinical evolution of these afected patients. MATERIAL AND METHODS: A retrospective, descriptive, observational study was reelized in three patients with diagnosis of pycnodisostosis, between July 2006 and March 2016. RESULTS: different affection forms of pycnodisostosis where observed, some of them, atipical, as for example spondilolisis and a escapule fracture in one patien. CONCLUSIONS: The present study could be the longest longitudinal report ever registered. By knowing the presented variety of manifestations and complications, the reader could select the best treatment method for each case.


INTRODUCCIÓN: La picnodisostosis es una rara enfermedad secundaria en una mutación en el gen 1q21 que codifica la catepsina K, enzima implicada en el metabolismo de osteonectina, osteopontina y colágeno I. La incidencia mundial es de 1-1.7 casos por millón, sin prevalencia por género, se caracteriza clínicamente por talla baja, deformidades craneales, «cara de pájaro¼ y fragilidad ósea con tendencia a fracturas patológicas, que afectan predominantemente los huesos largos y ocasionalmente en los pedículos vertebrales. Radiológicamente es característica la presencia de osteoesclerosis con canales medulares permeables. Aunque existen numerosos reportes de casos clínicos en la literatura, pocos son los que describen familias con más de un individuo afectado y el seguimiento suele ser a corto plazo. OBJETIVO: Analizar la evolución clínica de los pacientes afectados. MATERIAL Y MÉTODOS: Se realizó estudio retrospectivo, descriptivo, observacional de tres pacientes con diagnóstico de picnodisostosis, en el período de Julio 2006 a Marzo de 2016. RESULTADOS: Se observaron diferentes formas de afectación de la picnodisostosis, algunas de ellas atípicas como la espondilólisis y una fractura de escápula en una paciente. CONCLUSIONES: El presente estudio podría ser el análisis longitudinal más extenso del que se tenga registro. Conocer la variedad de manifestaciones y complicaciones presentadas permitirá al lector seleccionar el mejor método de tratamiento para cada caso.


Assuntos
Fraturas Espontâneas , Picnodisostose , Catepsina K/genética , Seguimentos , Fraturas Espontâneas/etiologia , Humanos , Picnodisostose/complicações , Picnodisostose/diagnóstico , Estudos Retrospectivos
9.
Leukemia ; 19(3): 336-43, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15674363

RESUMO

Increasing mixed chimerism (MC) after allogeneic stem cell transplantation (SCT) has been associated with a high risk of relapse in acute leukemia. We evaluated a new method for chimerism detection, based on the quantitative real-time PCR (qrt-PCR) amplification of null alleles or insertion/deletion polymorphisms (indels). All qrt-PCR assays with null alleles and indels attained a sensitivity of at least 10(-4), as well as good intra- and interassay concordance, and a high accuracy in experiments with cell mixtures. Informativeness was found in 80.3% of the 61 donor/recipient pairs tested. Nonrelapsed patients showed a progressive decrease in peripheral blood chimerism to values below 0.01% (complete chimerism (CC)). Bone marrow chimerism failed to reach CC more than 4 years after SCT. Increasing MC was observed prior to relapse in 88.2% of patients. Compared with conventional PCR amplification of variable number of tandem repeats, qrt-PCR predicted a significantly higher number of relapses (88.2 vs 44.4%) with a median anticipation period of 58 days. In conclusion, chimerism determination by qrt-PCR amplification of null alleles and indels constitutes a useful tool for the follow-up of patients with acute leukemia after SCT, showing better results than those obtained with conventional PCR.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Polimorfismo Genético , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Quimeras de Transplante/sangue , Adolescente , Adulto , Alelos , Criança , Pré-Escolar , DNA/análise , DNA/genética , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Estudos Prospectivos , Recidiva , Fatores de Risco , Análise de Sobrevida , Quimeras de Transplante/genética
10.
Rev Calid Asist ; 31(6): 338-346, 2016.
Artigo em Espanhol | MEDLINE | ID: mdl-27151650

RESUMO

OBJECTIVE: To investigate the opinion of Primary Care physicians regarding electronic prescribing. METHODS: Descriptive study by means of a questionnaire sent to 527 primary care physicians. PERIOD: June 2014. The questionnaire included closed questions about interest shown, satisfaction, benefits, weaknesses, and barriers, and one open question about difficulties, all of them referred to electronic prescribing. Satisfaction was measured using 1-10 scale, and benefits, weaknesses, and barriers were evaluated by a 5-ítems Likert scale. Interest was measured using both methods. The questionnaire was sent by e-mail for on line response through Google Drive® tool. A descriptive statistical analysis was performed. RESULTS: The response rate was 47% (248/527). Interest shown was 8.7 (95% CI; 8.5-8.9) and satisfaction was 7.9 (95% CI; 7.8-8). The great majority 87.9% (95% CI; 83.8-92%) of respondents used electronic prescribing where possible. Most reported benefits were: 73.4% (95% CI; 67.8-78.9%) of respondents considered that electronic prescribing facilitated medication review, and 59.3% (95% CI; 53.1-65.4) of them felt that it reduced bureaucratic burden. Among the observed weaknesses, they highlighted the following: 87.9% (95% CI; 83.8-92%) of respondents believed specialist care physicians should also be able to use electronic prescribing. Concerning to barriers: 30.2% (95% CI; 24.5-36%) of respondents think that entering a patient into the electronic prescribing system takes too much time, and 4% (95% CI; 1.6-6.5%) of them perceived the application as difficult to use. CONCLUSIONS: Physicians showed a notable interest in using electronic prescribing and high satisfaction with the application performance.


Assuntos
Prescrição Eletrônica , Médicos de Atenção Primária , Humanos , Padrões de Prática Médica , Espanha , Inquéritos e Questionários
11.
Acta Ortop Mex ; 30(4): 185-190, 2016.
Artigo em Espanhol | MEDLINE | ID: mdl-28267908

RESUMO

BACKGROUND: Several authors and publications have focused on comparing the clinical course of nerve root decompressive surgery, with or without fusion, to treat degenerative lumbar stenosis. However, there are not many reports analyzing the clinical course after decompressive surgery of a single nerve root (the most symptomatic one) comparing it with decompression of all the roots in a segment. This study intends to compare the clinical course after decompressing the most symptomatic lumbar nerve root with the release of multiple lumbar nerve roots to relieve neuropathic pain resulting from degenerative lumbar stenosis. MATERIAL AND METHODS: A prospective, observational, descriptive longitudinal study was performed. A total of 38 patients were divided into two groups that included each 19 cases. Patients underwent recalibration of either a single nerve root or multiple nerve roots of a segment. Percentages were calculated as well as the Student t test and the Pearson correlation. RESULTS: In group A, a decrease of 46.63 points was seen in the Oswestry scale, representing a 66.73% improvement in pain. In group B, in turn, a mean decrease of 34.54 points was seen in the Oswestry scale, equivalent to a 47.23% improvement in pain, with a Student t in which p = 0.11 and a Pearson correlation coefficient of 0.08. CONCLUSIONS: No statistically significant differences were found between both study groups.


Diversos autores y publicaciones se han enfocado en comparar la evolución clínica de la cirugía descompresiva de las raíces, ya sea con o sin fusión, para el tratamiento del canal lumbar estrecho degenerativo. Sin embargo, no existen muchos reportes que analicen la evolución clínica tras la cirugía descompresiva de una sola raíz nerviosa (la más sintomática) contra la descompresión de todas las raíces de un segmento. El presente estudio pretende comparar la evolución clínica de la liberación radicular lumbar de la raíz más sintomática con respecto a la liberación de múltiples raíces lumbares para el alivio del dolor neuropático en el canal lumbar estrecho degenerativo.


Assuntos
Descompressão Cirúrgica , Estenose Espinal , Constrição Patológica , Humanos , Laminectomia , Estudos Longitudinais , Vértebras Lombares , Estudos Prospectivos , Fusão Vertebral , Estenose Espinal/cirurgia , Resultado do Tratamento
12.
Biochim Biophys Acta ; 1326(1): 131-7, 1997 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-9188808

RESUMO

Lectin-binding studies were performed on rat pancreatic zymogen granules to investigate the alterations in the carbohydrate membrane composition under both chronic CCK stimulation and long-term CCK blockade for 3, 7 and 15 days. By flow cytometry using FITC-WGA--which specifically binds to N-acetylglucosamine and sialic acid--we measured the amount of WGA molecules bound to each individual granule. Parallel studies on pancreatic secretion were also carried out. CCK treatment displayed a differential effect on two zymogen granule subpopulations (Z1 and Z2) identified by flow cytometry on the basis of their light scatter properties: no effects on Z2 zymogen granules were observed in CCK-treated rats, while Z1 granules showed a significant increase in WGA binding at day + 7 which coincides with an increase in protein secretion in response to the hormone. On the contrary, a significant decrease in the amount of WGA receptors was observed in zymogen granule membrane of both the Z1 and Z2 subsets of rats subjected to a long-term CCK blockade. Again, these changes parallel to the reduction observed in protein secretion. Our results suggest that glycoconjugates of zymogen granule membrane involved in CCK-regulated exocytosis contain N-acetylglucosamine and sialic acid residues whose quantities are regulated by CCK.


Assuntos
Colecistocinina/farmacologia , Grânulos Citoplasmáticos/efeitos dos fármacos , Glicoproteínas de Membrana/metabolismo , Pâncreas/efeitos dos fármacos , Animais , Benzodiazepinonas/farmacologia , Grânulos Citoplasmáticos/metabolismo , Devazepida , Citometria de Fluxo , Fluoresceína-5-Isotiocianato/análogos & derivados , Proteínas Ligadas por GPI , Membranas Intracelulares/efeitos dos fármacos , Masculino , Glicoproteínas de Membrana/química , Pâncreas/metabolismo , Pâncreas/ultraestrutura , Suco Pancreático/química , Ratos , Ratos Wistar , Aglutininas do Germe de Trigo
13.
Neurotox Res ; 8(3-4): 259-66, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16371320

RESUMO

The mitochondrial toxin, 3-nitropropionic acid (3-NP), produces motor dysfunction and striatal atrophy in rats. However, rat strain and method of administration may contribute to variability in the deficits caused by 3-NP toxicity. To evaluate this, changes in nocturnal spontaneous locomotor activity from chronic administration of 3-NP using an osmotic mini pump, were examined in the Lewis rats. Lewis rats were treated with 3-NP or saline for 2 days and behavior was tested daily for a 15 day period. Animals receiving 3-NP displayed significantly less spontaneous activity than animals in the saline group. 3-NP treated animals also weighed significantly less when compared to saline treated animals. These results demonstrate that even though there were no significant alterations in overt anatomical pathology, even short-term exposure to 3-NP produced significant effects. This short-term administration may present a potential paradigm for examination of sub-threshold neurotoxicity.


Assuntos
Comportamento Animal/efeitos dos fármacos , Convulsivantes/administração & dosagem , Nitrocompostos/administração & dosagem , Propionatos/administração & dosagem , Animais , Peso Corporal/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Fosfoproteína 32 Regulada por cAMP e Dopamina/metabolismo , Esquema de Medicação , Proteína Glial Fibrilar Ácida/metabolismo , Imuno-Histoquímica/métodos , Masculino , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Endogâmicos Lew , Fatores de Tempo
14.
Neurosci Biobehav Rev ; 21(1): 79-90, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8994211

RESUMO

Cerebrovascular disease exemplifies the poor regenerative capacity of the CNS. While there are methods to prevent cerebral infarction, there is no effective therapy available to ameliorate the anatomical, neurochemical and behavioral deficits which follow cerebral ischemia. Focal and transient occlusion of the middle cerebral artery (MCA) in rodents has been reported to result in neuropathology similar to that seen in clinical cerebral ischemia. Using specific techniques, this MCA occlusion can result in a well-localized infarct of the striatum. This review article will provide data accumulated from animal studies using the MCA occlusion technique in rodents to examine whether neural transplantation can ameliorate behavioral and morphological deficits associated with cerebral infarction. Recent advances in neural transplantation as a treatment modality for neurodegenerative disorders such as Parkinson's disease, have revealed that fetal tissue transplantation may produce neurobehavioral recovery. Accordingly, fetal tissue transplantation may provide a potential therapy for cerebral infarction. Preliminary findings in rodents subjected to unilateral MCA occlusion, and subsequently transplanted with fetal striatal tissue into the infarcted striatum have produced encouraging results. Transplanted fetal tissue, assessed immunohistochemically, has been demonstrated to survive and integrate with the host tissue, and, more importantly, ameliorate the ischemia-related behavioral deficits, at least in the short term. Although, this review will focus primarily on cerebral ischemia, characterized by a localized CNS lesion within the striatum, it is envisioned that this baseline data may be extrapolated and applied to cerebral infarction in other brain areas.


Assuntos
Isquemia Encefálica/cirurgia , Transplante de Tecido Encefálico/fisiologia , Hipocampo/transplante , Animais , Modelos Animais de Doenças
15.
J Endocrinol ; 147(3): 431-40, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8543913

RESUMO

The effect of glucocorticoid deprivation induced in male rats by adrenalectomy on the pancreatic zymogen granules was studied. Zymogen granules were purified from control, sham-operated and adrenalectomized animals studied 1, 3 and 7 days after surgery. The zymogen granules were characterized by flow cytometry, and in each granule the size (based on the forward or low angle light scatter (FSC) parameter), membrane complexity (based on side or 90 degrees light scatter (SSC) parameter) and amylase content were evaluated. Amylase content/DNA ratio in pancreatic homogenates was also analyzed. The zymogen granules of the control rats were found to be distributed in two populations: a major one-R1 (95.45 +/- 1.21%)-containing zymogen granules with a smaller mean size and complexity, and a minor population-R2 (4.45 +/- 0.24%)-the granules of which had a mean size which was larger and more complex. At day +1 after adrenalectomy the zymogen granules were significantly (P < 0.05) smaller than those of control animals. The R2 zymogen granules were similar to those from R1 as regards their size, but were more complex, suggesting that the immediate effect of glucocorticoid deprivation is to induce a depletion of the larger granules presumably belonging to the R2 population. The amount of amylase per granule did not vary at day +1 after adrenalectomy, although the amylase content/size ratio per granule was significantly (P < 0.001) increased. This mechanism could be explained in terms of the existence of a bypass defined in the adrenalectomized animals between the granular content and cytosolic enzymes. Prolongation of the adrenalectomy period to 3 and 7 days resulted in a progressive increase in zymogen granule size and complexity, both parameters showing similar characteristics to those of the controls at day +7 after adrenalectomy. However, the percentage of zymogen granules within the R1 and R2 populations was clearly different from that of controls since the R2 population was much more numerous (11.25 +/- 0.75% and 15.25 +/- 1.15% (adrenalectomized rats at days +3 and +7 respectively) versus 4.45 +/- 0.24% (controls)). An increase in the content of amylase per DNA was observed in adrenalectomized rats at day +1 although this transient effect cannot be related to glucocorticoid deprivation because it was also observed in sham-operated rats (day +1). However, a significant reduction, nearly 64%, in the amylase content/DNA ratio is produced by the absence of glucocorticoids 7 days after adrenalectomy and this is associated with a reduction in the content of amylase in each individual zymogen granule which reaches a minimum 3 days after adrenalectomy. It should be noted that, despite this, the enzyme concentration in each granule remains constant as there is a parallel decrease in the zymogen granule amylase content and size.


Assuntos
Adrenalectomia , Amilases/metabolismo , Grânulos Citoplasmáticos/metabolismo , Pâncreas/enzimologia , Espalhamento de Radiação , Amilases/genética , Animais , DNA/análise , Citometria de Fluxo , Glucocorticoides/deficiência , Luz , Masculino , Pâncreas/metabolismo , Ratos , Ratos Wistar , Fatores de Tempo
16.
Mol Cell Endocrinol ; 133(2): 117-25, 1997 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-9406857

RESUMO

Lectin-binding studies were performed on rat pancreatic zymogen granules to investigate the influence of glucocorticoid levels on saccharide membrane composition. The following animal groups were used: (1) control rats; (2) rats treated with hydrocortisone (1, 10 and 25 mg/kg/day) for 1, 3 and 8 days; (3) postadrenalectomized rats at days +1, +3 and +8; and (4) adrenalectomized rats receiving hydrocortisone therapy (10 mg/kg/day) for 8 days. By flow cytometry, fluoresceinated (FITC) lectins were used to measure the amount of Concanavalin A (Con A) (specific for D-mannose), wheat germ agglutinin (WGA) (specific for N-acetyl-D-glucosamine) and sialic acids and Tetragonolobus purpureus (TP) (specific for L-fucose) bound to individual zymogen granules from two subpopulations, Z1 and Z2, identified on the basis of their forward and side scatter properties. The molar ratio of the different FITC-lectins revealed significant differences in the glycoconjugate composition of Z1 and Z2 granules, the Z1 granules showing higher ratios of N-acetyl-D-glucosamine:L-fucose and N-acetyl-D-glucosamine:D-mannose, both in control, adrenalectomized and hydrocortisone-treated rats. It was also observed that N-acetyl-D-glucosamine and/or sialic acids were more abundant than L-fucose and D-mannose in the zymogen granule membrane. Z1 and Z2 granules had different glycosylation patterns. Neither adrenalectomy nor hydrocortisone treatments varied the Con A binding to zymogen granules. An increase in WGA binding was only induced by administration of very high doses of hydrocortisone (25 mg/kg/day) for 8 days, an effect not directly related to glucocorticoids. In contrast, a correlation between the FITC-TP labelling and glucocorticoid levels can be established, so that, in a time-dose dependent way, an increase was observed in zymogen granules of rats treated with hydrocortisone while a decreased TP binding was found in adrenalectomized rats-an effect which was reversed with hydrocortisone therapy. Therefore, glucocorticoids exert a direct influence on the saccharide composition of rat pancreatic zymogen granules, regulating the amount of L-fucose glycoconjugates, with Z2 granules more sensitive than Z1 ones.


Assuntos
Grânulos Citoplasmáticos/metabolismo , Precursores Enzimáticos/metabolismo , Fucose/metabolismo , Glucocorticoides/farmacologia , Glicoconjugados/metabolismo , Pâncreas/metabolismo , Acetilglucosamina/metabolismo , Glândulas Suprarrenais/fisiologia , Adrenalectomia , Animais , Citometria de Fluxo , Glicosilação , Hidrocortisona/farmacologia , Membranas Intracelulares/metabolismo , Lectinas/metabolismo , Masculino , Pâncreas/enzimologia , Ratos , Ratos Wistar
17.
J Clin Psychiatry ; 59 Suppl 10: 16-21, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9720478

RESUMO

Both depression and cardiovascular disease are common as people age and are, therefore, likely to coexist. It has become evident recently that the rate of this comorbidity exceeds substantially what is expected by chance. A major problem arises in that there is increasing evidence that the tricyclic antidepressants (TCAs) carry more risk than originally thought in patients with ischemic heart disease. This risk increases the importance of understanding both the safety and efficacy of the serotonin selective reuptake inhibitors (SSRIs) in this population. Three recent studies on safety data in patients with overt heart disease are now available: although the total of 94 patients limits the ability to make generalizations, the data that are available give little evidence of harm and even suggest that SSRIs may have beneficial effects in ischemic heart disease.


Assuntos
Antidepressivos/uso terapêutico , Transtorno Depressivo/tratamento farmacológico , Cardiopatias/epidemiologia , Fatores Etários , Antidepressivos/efeitos adversos , Antidepressivos Tricíclicos/efeitos adversos , Antidepressivos Tricíclicos/uso terapêutico , Arritmias Cardíacas/epidemiologia , Comorbidade , Transtorno Depressivo/epidemiologia , Humanos , Isquemia Miocárdica/epidemiologia , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico
18.
J Steroid Biochem Mol Biol ; 62(5-6): 439-48, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9449247

RESUMO

This study was performed to evaluate the effects of different doses of hydrocortisone (1, 10 and 25 mg/kg/day) administered for 1, 3 and 8 days on pancreatic enzyme storage in rats. The enzyme content in both pancreas homogenates and in individual isolated zymogen granules (ZGs) was measured using standard biochemical assays and flow cytometry, respectively. Hydrocortisone did not alter the total amount of pancreatic DNA but increased the pancreas enzyme content in a time-dose-dependent way. Amylase activity was significantly increased after hydrocortisone administration at day +8 when 10 mg/kg/day was used, and from the first day of treatment when 25 mg/kg/day was administered. A significant increase in trypsin activity was also observed in response to 25 mg/kg/day of hydrocortisone but only from the third day of treatment onwards. As compared with control rats, chronic administration of either 1 or 10 mg/kg/day of hydrocortisone did not alter significantly either the size or the percentage of the two ZG subpopulations (Z1 and Z2) identified in the pancreas by flow cytometry; in addition, no significant changes were observed in the mean amylase content per individual granule, although its mean concentration increased in rats treated with 10 mg/kg/day for 3 and 8 days. Nevertheless, when 25 mg/kg/day of hydrocortisone were administered for 1 and 3 days, a significant increase in the proportion of Z1 ZGs was observed, which may be related to the formation of new and smaller ZGs. When a very high dose of hydrocortisone (25 mg/kg/day) was used, an overall increase in the pancreatic enzyme content related to an increase in the mean amylase content per individual ZG was observed; this effect was apparent from the first day of treatment in the Z1 subset of ZGs and from day +3 in the Z2 subpopulation. Only a high concentration of hydrocortisone was able to alter the enzyme storage process in individual zymogen granules, but they maintain a normal enzyme load at lower hydrocortisone doses.


Assuntos
Amilases/metabolismo , Hidrocortisona/farmacologia , Pâncreas/efeitos dos fármacos , Pâncreas/enzimologia , Animais , Grânulos Citoplasmáticos/efeitos dos fármacos , Grânulos Citoplasmáticos/enzimologia , DNA/metabolismo , Relação Dose-Resposta a Droga , Precursores Enzimáticos/metabolismo , Hematócrito , Hidrocortisona/administração & dosagem , Masculino , Tamanho do Órgão/efeitos dos fármacos , Pâncreas/anatomia & histologia , Ratos , Ratos Wistar
19.
Cell Transplant ; 9(6): 751-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11202562

RESUMO

Taurine acts as an antioxidant able to protect neurons from free radical-mediated cellular damage. Moreover, it modulates the immune response of astrocytes that participate in neurodegenerative processes. The objective of this study was to examine whether taurine can prevent or attenuate the host inflammatory response induced by the xenotransplantation of neurons derived from the human teratocarcinoma cell line (hNT neurons). Male Sprague-Dawley rats were treated IP with either saline or taurine. Animals from both groups were perfused on the 4th or 11th day and the saline or taurine was administered from the start of the study until the day prior to sacrifice. The brains were processed immunohistochemically using antibodies against glial fibrillary acidic protein (GFAP), microglia (OX42), and human nuclear matrix antigen (NuMA). In the saline group, NuMA labeling revealed small grafts on the 4th day and no surviving cells on the 11th day. However, in the group that received taurine there were surviving grafts at both time points. Strong immunoreactivity for GFAP and OX42 was detected in the saline group surrounding the transplant. These effects were reduced in animals receiving taurine. Taken together, these results demonstrated that taurine was able to facilitate graft survival and attenuate the immune response generated by the xenograft.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Corpo Estriado/patologia , Degeneração Neural/tratamento farmacológico , Taurina/farmacologia , Teratocarcinoma/tratamento farmacológico , Animais , Antioxidantes/farmacologia , Astrócitos/química , Astrócitos/metabolismo , Astrócitos/patologia , Neoplasias Encefálicas/patologia , Proteínas de Ciclo Celular , Corpo Estriado/metabolismo , Corpo Estriado/cirurgia , Proteína Glial Fibrilar Ácida/análise , Sobrevivência de Enxerto/efeitos dos fármacos , Imuno-Histoquímica , Masculino , Microglia/química , Microglia/metabolismo , Microglia/patologia , Transplante de Neoplasias , Degeneração Neural/metabolismo , Degeneração Neural/patologia , Neurônios/metabolismo , Neurônios/patologia , Proteínas Nucleares/análise , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Teratocarcinoma/patologia , Transplante Heterólogo
20.
Pancreas ; 15(3): 314-22, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9336798

RESUMO

To determine the effect of long-term blockade of cholecystokinin (CCK) on both pancreatic storage and secretion processes, L 364,718 (a CCK receptor antagonist) was administered to rats at 0.1 mg/kg/day for 3, 7, and 15 days. Zymogen granules were analyzed by flow cytometry to determine their light scattering properties-forward scatter and side scatter-as well as their amylase content measured by a specific antiserum. The mean number of zymogen granules per cell was counted on pancreatic sections using electron microscopy. DNA content, pancreatic weight, and enzyme secretion were also studied under both basal conditions and CCK infusion at a dose of 1.25 micrograms/kg/h, which is able to displace the CCK receptor antagonist. Two subpopulations of zymogen granules (Z1 and Z2) were identified on the basis of their light scattering parameters, in both control and L 364,718-treated rats. L 364,718 administered for 3, 7, and 15 days induced a significant reduction in the amylase content of individual zymogen granules, for both Z1 and Z2 zymogen granule subsets. In contrast, the number of zymogen granules per cell increased from day +3 of treatment onward, the highest values being detected at day +7. Hyperplasia was observed only at day +15. Basal enzyme secretion decreased significantly in rats treated with L 364,718 for 3 and 7 days but recovered to control values after 15 days of treatment. No significant differences in CCK-stimulated amylase secretion were observed between control and L 364,718-treated rats. At day +15 of L 364,718 treatment a significant increase in enzyme secretion was observed with respect to shorter treatment periods; this was associated with a significant increase in both the number of cells and the number of zymogen granules per cell. Our results indicate that chronic administration of L 364,718 induces a biphasic effect on pancreatic function. Interestingly, although enzyme secretion reached recovery after long-term treatment (15 days), the storage process is altered since the mean enzyme content in each individual zymogen granule remains significantly reduced.


Assuntos
Benzodiazepinonas/farmacologia , Colecistocinina/antagonistas & inibidores , Antagonistas de Hormônios/farmacologia , Pâncreas/efeitos dos fármacos , Pâncreas/enzimologia , Amilases/metabolismo , Animais , Grânulos Citoplasmáticos/ultraestrutura , DNA/metabolismo , Devazepida , Precursores Enzimáticos/metabolismo , Citometria de Fluxo , Masculino , Microscopia Eletrônica , Tamanho do Órgão , Pâncreas/ultraestrutura , Proteínas/metabolismo , Ratos , Ratos Wistar , Tripsina/metabolismo , Aumento de Peso
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