Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
1.
Sensors (Basel) ; 23(2)2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36679804

RESUMO

This article presents the results regarding a systematic literature review procedure on digital twins applied to precision agriculture. In particular, research and development activities aimed at the use of digital twins, in the context of predictive control, with the purpose of improving soil quality. This study was carried out through an exhaustive search of scientific literature on five different databases. A total of 158 articles were extracted as a result of this search. After a first screening process, only 11 articles were considered to be aligned with the current topic. Subsequently, these articles were categorised to extract all relevant information, using the preferred reporting items for systematic reviews and meta-analyses methods. Based on the obtained results, there are two main conclusions to draw: First, when compared with industrial processes, there is only a very slight rising trend regarding the use of digital twins in agriculture. Second, within the time frame in which this work was carried out, it was not possible to find any published paper on the use of digital twins for soil quality improvement within a model predictive control context.


Assuntos
Solo
2.
Chemistry ; 25(38): 8960-8964, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-30920063

RESUMO

Statistical copolymerization plays a key role in many biological and technological processes; however, mechanistic understanding of the formation of analogous supramolecular counterparts remains limited. Herein, we report detailed insights into the supramolecular co-assembly of two π-conjugated PdII and PtII complexes, which in isolation self-assemble into flexible fibers and nanodisks, respectively. An efficient single-step co-assembly into only one type of nanostructure (fibers or nanodisks) takes place if any of the components is in excess. In contrast, equimolar mixtures lead to PdII -rich fiber-like co-assemblies by a statistical co-nucleation event along with a residual amount of self-sorted nanodisks in a stepwise manner.

3.
J Am Chem Soc ; 139(3): 1120-1128, 2017 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-28036174

RESUMO

The ability to respond toward mechanical stimuli is a fundamental property of biological organisms at both the macroscopic and cellular levels, yet it has been considerably less observed in artificial supramolecular and colloidal homologues. An archetypal example in this regard is cellular mechanosensation, a process by which mechanical forces applied on the cell membrane are converted into biochemical or electrical signals through nanometer-scale changes in molecular conformations. In this article, we report an artificial gold nanoparticle (Au NP)-discrete π-conjugated molecule hybrid system that mimics the mechanical behavior of biological membranes and is able to self-assemble into colloidal gold nanoclusters or membranes in a controlled and reversible fashion by changing the concentration or the mechanical force (pressure) applied. This has been achieved by rational design of a small π-conjugated thiolated molecule that controls, to a great extent, the hierarchy levels involved in Au NP clustering by enabling reversible, cooperative non-covalent (π-π, solvophobic, and hydrogen bonding) interactions. In addition, the Au NP membranes have the ability to entrap and release aromatic guest molecules reversibly (Kb = 5.0 × 105 M-1) for several cycles when subjected to compression-expansion experiments, in close analogy to the behavior of cellular mechanosensitive channels. Not only does our hybrid system represent the first example of a reversible colloidal membrane, but it also can be controlled by a dynamic mechanical stimulus using a new supramolecular surface-pressure-controlled strategy. This approach holds great potential for the development of multiple colloidal assemblies within different research fields.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Coloides/química , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
4.
Nano Lett ; 14(9): 5458-70, 2014 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-25115645

RESUMO

Properties like high interfacial area with cellular membranes, unique ability to incorporate multiple functionalization, as well as compatibility and transport in biological fluids make carbon nanotubes (CNTs) useful for a variety of therapeutic and drug-delivery applications. Here we used a totally synthetic hybrid supramolecule as an anticancer vaccine formulation. This complex structure comprises CNTs as delivery system for the Cancer Testis Antigen named NY-ESO-1, allied to a synthetic Toll-Like Receptor agonist. The CNT constructs were rapidly internalized into dendritic cells, both in vitro and in vivo, and served as an intracellular antigen depot. This property favored the induction of strong CD4(+) T as well as CD8(+) T cell-mediated immune responses against the NY-ESO-1. Importantly, the vaccination significantly delayed the tumor development and prolonged the mice survival, highlighting the potential application of CNTs as a vaccine delivery system to provide superior immunogenicity and strong protection against cancer.


Assuntos
Linfócitos T CD8-Positivos/citologia , Vacinas Anticâncer/química , Nanotecnologia/métodos , Nanotubos de Carbono/química , Neoplasias/prevenção & controle , Neoplasias/terapia , Animais , Anticarcinógenos/química , Antígenos/química , Antígenos de Neoplasias/química , Linfócitos T CD4-Positivos/citologia , Calibragem , Proliferação de Células , Ilhas de CpG , Células Dendríticas/efeitos dos fármacos , Feminino , Citometria de Fluxo , Humanos , Linfócitos/citologia , Proteínas de Membrana/química , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Neoplasias/metabolismo , Oxigênio/química , Peptídeos/química , Análise Espectral Raman
5.
Angew Chem Int Ed Engl ; 53(47): 12751-5, 2014 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-25256384

RESUMO

The use of a thiol-functionalized nonionic surfactant to stabilize spherical gold nanoparticles in water induces the spontaneous formation of polyrotaxanes at the nanoparticle surface in the presence of the macrocycle α-cyclodextrin. Whereas using an excess of surfactant an amorphous gold nanocomposite is obtained, under controlled drying conditions the self-assembly between the surface supramolecules provides large and homogenous supercrystals with hexagonal close packing of nanoparticles. Once formed, the self-assembled supercrystals can be fully redispersed in water. The reversibility of the crystallization process may offer an excellent reusable material to prepare gold nanoparticle inks and optical sensors with the potential to be recovered after use.

6.
Colloids Surf B Biointerfaces ; 175: 175-183, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30530003

RESUMO

The interaction between carbon nanotubes (CNTs) and biological molecules of diagnostic and therapeutic interest, as well as the internalization of the CNTs-biomolecules complexes in different types of cell, has been extensively studied due to the potential use of these nanocomplexes as multifunctional nanoplatforms in a great variety of biomedical applications. The effective use of these nanobiotechnologies requires broad multidisciplinary studies of biocompatibility, regarding, for example, the in vitro and in vivo nanotoxicological assays, the capacity to target specific cells and the evaluation of their biomedical potential. However, the first step to be reached is the careful obtainment of the nanoplatform and the understanding of the actual surface composition and structural integrity of the complex system. In this work, we show the detailed construction of a nanoplatform created by the noncovalent interaction between oxidized multi walled carbon nanotubes (MWCNTs) and a DNA aptamer targeting tumor cells. The excess free aptamer was removed by successive washes, revealing the actual surface of the nanocomplex. The MWCNT-aptamer interaction by π-stacking was evidenced and shown to contribute in obtaining a stable nanocomplex compatible with aqueous media having good cell viability. The nucleotide sequence of the aptamer remained intact after the functionalization, allowing its use in further studies of specificity and binding affinity and for the construction of functional nanoplatforms.


Assuntos
Aptâmeros de Nucleotídeos/química , Materiais Biocompatíveis/química , Nanotecnologia/métodos , Nanotubos de Carbono/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Microscopia Eletrônica de Transmissão , Nanotubos de Carbono/ultraestrutura , Oxirredução
7.
Acta Cir Bras ; 32(4): 297-306, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28538804

RESUMO

PURPOSE:: To evaluated the effects of L-lysine on the intestinal and urothelial epithelia in cystoplasty in rats. METHODS:: Twenty-eight 9-week-old rats were assigned to 4 groups: Group A (n=8) cystoplasty followed by administration of L-lysine (150 mg/kg body weight by gavage) for 30 weeks; Group B (n=8) cystoplasty + water for 30 weeks; Group C (n=6) L-lysine for 30 weeks; Group D (n=6) water for 30 weeks. RESULTS:: On histopathology with hematoxylin and eosin, mild to moderate hyperplasia transitional was observed in at the site of anastomosis in all animals submitted to cystoplasty (Groups A and B), but "transitional metaplasia" of the intestinal glandular epithelium was more accentuated in Group A (p=0.045). No inflammatory cells, dysplasia or abnormalities were observed. Staining with Alcian blue revealed a substantial reduction of goblet cells and mucins in the colon segment (Groups A and B). CONCLUSION:: The administration of L-lysine to rats accelerated the development of transitional metaplasia in the epithelium of the colon segment in cystoplasty.


Assuntos
Carcinogênese/induzido quimicamente , Mucosa Intestinal/patologia , Mucosa Intestinal/cirurgia , Lisina/efeitos adversos , Animais , Carcinogênese/patologia , Modelos Animais de Doenças , Feminino , Lisina/administração & dosagem , Metaplasia/induzido quimicamente , Metaplasia/patologia , Ratos , Bexiga Urinária/cirurgia , Derivação Urinária
8.
Adv Colloid Interface Sci ; 233: 255-270, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26094082

RESUMO

Colloidal metal nanoparticles present very special optical and electromagnetic properties at the nanoscale range. Such plasmonic properties have derived in a huge research field that encompasses the understanding of nanoparticle formation mechanisms for the ultimate goal of developing novel materials for real-life applications. Plasmonic sensing is experiencing a rapid transition by taking advantage of the characteristic properties of colloidal metal nanoparticles. However, a rational design of novel nanoplasmonic substrates, which gathers as much as the required properties for a substrate to be a 'good' sensor is critical through the development of applications that can be effectively transferred as applied technologies. Also, the chosen sensing technique is a key factor when planning the design of a new plasmonic-based sensor. Several factors such as composition, shape, size, particle interactions or stability among others will define the final quality of the nanomaterial as sensing platform. Herein, we review the latest and most promising state-of-the art of nanoplasmonic-based sensors in four differentiated areas regarding the surface-enhanced spectroscopy detection technique being LSPR-, SERS- and SEIRA-, and SEF based platforms.

9.
Acta Cir Bras ; 31(12): 793-800, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28076502

RESUMO

PURPOSE:: To evaluate the effects of L-lysine on the intestinal and urothelial epithelium of rats subjected to ureterosigmoidostomy (new model for surgical carcinogenesis). METHODS:: Forty-two rats, 9 weeks of age, were divided into 6 groups. Animals in groups A, B, C were subjected to ureterosigmoidostomy (US) and treated with L-lysine, celecoxib and H2O, respectively. Groups D, E and F (non-operated controls) received L-lysine, celecoxib and H2O, respectively. The L-lysine dose was 150 mg/kg and that of celecoxib was 20 mg/kg. The colon was analyzed for the presence of aberrant crypt foci (ACF) under a stereomicroscope.The tissue was stained with hematoxylin and eosin and PAS alcian blue. RESULTS:: There were rare ACF, and there was no statistically significant difference between the groups. Histopathologic study of the ureteral epithelium identified moderate to severe urothelial hyperplasia in rats with ureterosigmoidostomy. Transitional hyperplasia in the ureters of animals receiving L-lysine (A) showed an apparent difference compared to the control (C) (P=0.2424). There was no dysplasia or atypia. CONCLUSION:: L-lysine does not promote carcinogenesis of the intestinal and urethelial epithelium of rats subjected to ureterosigmoidostomy at the doses and times studied.


Assuntos
Focos de Criptas Aberrantes/patologia , Carcinogênese , Colo Sigmoide/cirurgia , Neoplasias Intestinais/etiologia , Lisina/farmacologia , Estomas Cirúrgicos , Ureterostomia/efeitos adversos , Derivação Urinária , Neoplasias Urológicas/etiologia , Animais , Modelos Animais de Doenças , Feminino , Mucosa Intestinal/patologia , Ratos , Ratos Wistar , Estomas Cirúrgicos/efeitos adversos , Ureterostomia/métodos , Neoplasias da Bexiga Urinária/etiologia
10.
Rev Col Bras Cir ; 43(2): 80-6, 2016.
Artigo em Inglês, Português | MEDLINE | ID: mdl-27275588

RESUMO

OBJECTIVE: to evaluate the effect of L-lysine in the bladder and intestinal epithelia in rats submitted to vesicosigmoidostomy. METHODS: we divided forty Wistar rats into four groups: group I - control group (Sham); group II - submitted to vesicosigmoidostomy and treated with L-lysine 150mg/kg; group III - submitted only to vesicosigmoidostomy; and group IV - received L-lysine 150mg/kg. After eight weeks the animals were sacrificed. RESULTS: in the bladders of all operated animals we observed simple, papillary and nodular hyperplasia of transitional cells, transitional cell papillomas and squamous metaplasia. As for the occurrence of aberrant crypt foci in the colons of operated animals, we did not observe statistically significant differences in any of the distal, proximal and medium fragments, or in all fragments together (p=1.0000). CONCLUSION: Although statistically there was no promotion of carcinogenesis in the epithelia of rats treated with L-lysine in the observed time, it was clear the histogenesis of bladder carcinogenesis in its initial phase in all operated rats, this being probably associated with chronic infection and tiny bladder stones. OBJETIVO: o objetivo deste trabalho é avaliar o efeito da L-lisina nos epitélios vesical e intestinal de ratas submetidas à vesicossigmoidostomia. MÉTODOS: quarenta ratas Wistar, foram divididas em quatro grupos: grupo I- grupo controle (Sham); grupo II- submetido à vesicossigmoidostomia e tratado com L-lisina 150mg/kg; grupo III- submetido apenas à vesicossigmoidostomia; e grupo IV- recebeu L-lisina 150mg/kg. Após oito semanas os animais foram sacrificados. RESULTADOS: na bexiga de todos os animais operados observou-se hiperplasia simples, papilar e nodular de células transicionais, papiloma de células transicionais e metaplasia escamosa. Quanto à ocorrência de focos de criptas aberrantes nos colos dos animais operados, não foi evidenciado diferença estatística significante em nenhum dos fragmentos distal, proximal e médio, e todos juntos (P=1,0000). CONCLUSÃO: apesar de, estatisticamente, não ter havido promoção de carcinogênese nos epitélios dos ratos tratados com L-lisina, no tempo observado, é nítida a histogênese da carcinogênese de bexiga em sua fase inicial, no epitélio vesical, em todos os ratos operados, estando esta provavelmente associada à infecção crônica e aos diminutos cálculos vesicais.


Assuntos
Carcinogênese/induzido quimicamente , Colo Sigmoide/cirurgia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Lisina/farmacologia , Complicações Pós-Operatórias/induzido quimicamente , Ureterostomia , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/patologia , Animais , Ratos , Ratos Wistar
11.
ACS Nano ; 9(11): 11241-8, 2015 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-26493583

RESUMO

The transfer of information encoded by molecular subcomponents is a key phenomenon that regulates the biological inheritance in living organisms, yet there is a lack of understanding of related transfer mechanisms at the supramolecular level in artificial multicomponent systems. Our contribution to tackle this challenge has focused on the design of a thiolated π-conjugated linking unit, whose hierarchical, cooperative self-assembly in nonpolar media can be efficiently transferred from the molecular to the nanoscopic level, thereby enabling the reversible self-assembly of gold nanoparticle (AuNP) clusters. The transfer of supramolecular information by the linking π-system can only take place when a specific cooperative nucleation-elongation mechanism is operative, whereas low-ordered noncooperative assemblies formed below a critical concentration do not suffice to extend the order to the AuNP level. To the best of our knowledge, our approach has allowed for the first time a deep analysis of the hierarchy levels and thermodynamics involved in the self-assembly of AuNPs.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Polímeros/química , Microscopia de Força Atômica , Espectrofotometria Ultravioleta , Compostos de Sulfidrila/química , Temperatura
12.
Spine (Phila Pa 1976) ; 38(12): 984-90, 2013 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-23324939

RESUMO

STUDY DESIGN: Laboratory based controlled in vivo study. OBJECTIVE: To determine the in vivo effects of oral glucosamine sulfate on intervertebral disc degeneration. SUMMARY OF BACKGROUND DATA: Although glucosamine has demonstrated beneficial effect in articular cartilage, clinical benefit is uncertain. A Centers for Disease Control report from 2009 reported that many patients are using glucosamine supplementation for low back pain, without significant evidence to support its use. Because disc degeneration is a major contributor of low back pain, we explored the effects of glucosamine on disc matrix homeostasis in an animal model of disc degeneration. METHODS: Eighteen skeletally mature New Zealand White rabbits were divided into 4 groups: control, annular puncture, glucosamine, and annular puncture + glucosamine. Glucosamine treated rabbits received daily oral supplementation with 107 mg/d (weight based equivalent to human 1500 mg/d). Annular puncture surgery involved puncturing the annulus fibrosus of 3 lumbar discs with a 16-gauge needle to induce degeneration. Serial magnetic resonance images were obtained at 0, 4, 8, 12, and 20 weeks. Discs were harvested at 20 weeks for determination of glycosaminoglycan content, relative gene expression measured by real time polymerase chain reaction, and histological analyses. RESULTS: The magnetic resonance imaging index and nucleus pulposus area of injured discs of glucosamine treated animals with annular puncture was found to be lower than that of degenerated discs from rabbits not supplemented with glucosamine. Consistent with this, decreased glycosaminoglycan was demonstrated in glucosamine fed animals, as determined by both histological and glycosaminoglycan content. Gene expression was consistent with a detrimental effect on matrix. CONCLUSION: These data demonstrate that the net effect on matrix in an animal model in vivo, as measured by gene expression, magnetic resonance imaging, histology, and total proteoglycan is antianabolic. This raises concern about this commonly used supplement, and future research is needed to establish the clinical relevance of these findings.


Assuntos
Suplementos Nutricionais/toxicidade , Matriz Extracelular/metabolismo , Glucosamina/toxicidade , Degeneração do Disco Intervertebral/tratamento farmacológico , Disco Intervertebral/efeitos dos fármacos , Vértebras Lombares/efeitos dos fármacos , Administração Oral , Animais , Disponibilidade Biológica , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Glucosamina/administração & dosagem , Glucosamina/farmacocinética , Glicosaminoglicanos/metabolismo , Disco Intervertebral/metabolismo , Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/genética , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/patologia , Vértebras Lombares/metabolismo , Vértebras Lombares/patologia , Imageamento por Ressonância Magnética , Coelhos , Fatores de Tempo
13.
Spine J ; 13(3): 263-72, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23384411

RESUMO

BACKGROUND CONTEXT: Patients often present to spine clinic with evidence of intervertebral disc degeneration (IDD). If conservative management fails, a safe and effective injection directly into the disc might be preferable to the risks and morbidity of surgery. PURPOSE: To determine whether injecting human umbilical tissue-derived cells (hUTC) into the nucleus pulposus (NP) might improve the course of IDD. DESIGN: Prospective, randomized, blinded placebo-controlled in vivo study. PATIENT SAMPLE: Skeletally mature New Zealand white rabbits. OUTCOME MEASURES: Degree of IDD based on magnetic resonance imaging (MRI), biomechanics, and histology. METHODS: Thirty skeletally mature New Zealand white rabbits were used in a previously validated rabbit annulotomy model for IDD. Discs L2-L3, L3-L4, and L4-L5 were surgically exposed and punctured to induce degeneration and then 3 weeks later the same discs were injected with hUTC with or without a hydrogel carrier. Serial MRIs obtained at 0, 3, 6, and 12 weeks were analyzed for evidence of degeneration qualitatively and quantitatively via NP area and MRI Index. The rabbits were sacrificed at 12 weeks and discs L4-L5 were analyzed histologically. The L3-L4 discs were fixed to a robotic arm and subjected to uniaxial compression, and viscoelastic displacement curves were generated. RESULTS: Qualitatively, the MRIs demonstrated no evidence of degeneration in the control group over the course of 12 weeks. The punctured group yielded MRIs with the evidence of disc height loss and darkening, suggestive of degeneration. The three treatment groups (cells alone, carrier alone, or cells+carrier) generated MRIs with less qualitative evidence of degeneration than the punctured group. MRI Index and area for the cell and the cell+carrier groups were significantly distinct from the punctured group at 12 weeks. The carrier group generated MRI data that fell between control and punctured values but failed to reach a statistically significant difference from the punctured values. There were no statistically significant MRI differences among the three treatment groups. The treated groups also demonstrated viscoelastic properties that were distinct from the control and punctured values, with the cell curve more similar to the punctured curve and the carrier curve and carrier+cells curve more similar to the control curve (although no creep differences achieved statistical significance). There was some histological evidence of improved cellularity and disc architecture in the treated discs compared with the punctured discs. CONCLUSIONS: Treatment of degenerating rabbit intervertebral discs with hUTC in a hydrogel carrier solution might help restore the MRI, histological, and biomechanical properties toward those of nondegenerated controls. Treatment with cells in saline or a hydrogel carrier devoid of cells also might help restore some imaging, architectural, and physical properties to the degenerating disc. These data support the potential use of therapeutic cells in the treatment of disc degeneration.


Assuntos
Transplante de Células/métodos , Degeneração do Disco Intervertebral/terapia , Disco Intervertebral/patologia , Cordão Umbilical/citologia , Animais , Modelos Animais de Doenças , Feminino , Humanos , Degeneração do Disco Intervertebral/patologia , Imageamento por Ressonância Magnética , Estudos Prospectivos , Coelhos
14.
Acta cir. bras ; Acta cir. bras;32(4): 297-306, Apr. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-837697

RESUMO

Abstract Purpose: To evaluated the effects of L-lysine on the intestinal and urothelial epithelia in cystoplasty in rats. Methods: Twenty-eight 9-week-old rats were assigned to 4 groups: Group A (n=8) cystoplasty followed by administration of L-lysine (150 mg/kg body weight by gavage) for 30 weeks; Group B (n=8) cystoplasty + water for 30 weeks; Group C (n=6) L-lysine for 30 weeks; Group D (n=6) water for 30 weeks. Results: On histopathology with hematoxylin and eosin, mild to moderate hyperplasia transitional was observed in at the site of anastomosis in all animals submitted to cystoplasty (Groups A and B), but "transitional metaplasia" of the intestinal glandular epithelium was more accentuated in Group A (p=0.045). No inflammatory cells, dysplasia or abnormalities were observed. Staining with Alcian blue revealed a substantial reduction of goblet cells and mucins in the colon segment (Groups A and B). Conclusion: The administration of L-lysine to rats accelerated the development of transitional metaplasia in the epithelium of the colon segment in cystoplasty.


Assuntos
Animais , Feminino , Ratos , Carcinogênese/induzido quimicamente , Mucosa Intestinal/cirurgia , Mucosa Intestinal/patologia , Lisina/efeitos adversos , Derivação Urinária , Bexiga Urinária/cirurgia , Modelos Animais de Doenças , Carcinogênese/patologia , Lisina/administração & dosagem , Metaplasia/induzido quimicamente , Metaplasia/patologia
15.
Acta cir. bras ; Acta cir. bras;31(12): 793-800, Dec. 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-837657

RESUMO

ABSTRACT PURPOSE: To evaluate the effects of L-lysine on the intestinal and urothelial epithelium of rats subjected to ureterosigmoidostomy (new model for surgical carcinogenesis). METHODS: Forty-two rats, 9 weeks of age, were divided into 6 groups. Animals in groups A, B, C were subjected to ureterosigmoidostomy (US) and treated with L-lysine, celecoxib and H2O, respectively. Groups D, E and F (non-operated controls) received L-lysine, celecoxib and H2O, respectively. The L-lysine dose was 150 mg/kg and that of celecoxib was 20 mg/kg. The colon was analyzed for the presence of aberrant crypt foci (ACF) under a stereomicroscope.The tissue was stained with hematoxylin and eosin and PAS alcian blue. RESULTS: There were rare ACF, and there was no statistically significant difference between the groups. Histopathologic study of the ureteral epithelium identified moderate to severe urothelial hyperplasia in rats with ureterosigmoidostomy. Transitional hyperplasia in the ureters of animals receiving L-lysine (A) showed an apparent difference compared to the control (C) (P=0.2424). There was no dysplasia or atypia CONCLUSION: L-lysine does not promote carcinogenesis of the intestinal and urethelial epithelium of rats subjected to ureterosigmoidostomy at the doses and times studied.


Assuntos
Animais , Feminino , Ratos , Colo Sigmoide/cirurgia , Estomas Cirúrgicos , Focos de Criptas Aberrantes/patologia , Carcinogênese , Neoplasias Intestinais/etiologia , Lisina/farmacologia , Neoplasias da Bexiga Urinária/etiologia , Ureterostomia/métodos , Ratos Wistar , Modelos Animais de Doenças , Estomas Cirúrgicos/efeitos adversos , Mucosa Intestinal/patologia
16.
Rev. Col. Bras. Cir ; 43(2): 80-86, Mar.-Apr. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-782916

RESUMO

ABSTRACT Objective: to evaluate the effect of L-lysine in the bladder and intestinal epithelia in rats submitted to vesicosigmoidostomy. Methods: we divided forty Wistar rats into four groups: group I - control group (Sham); group II - submitted to vesicosigmoidostomy and treated with L-lysine 150mg/kg; group III - submitted only to vesicosigmoidostomy; and group IV - received L-lysine 150mg/kg. After eight weeks the animals were sacrificed. Results: in the bladders of all operated animals we observed simple, papillary and nodular hyperplasia of transitional cells, transitional cell papillomas and squamous metaplasia. As for the occurrence of aberrant crypt foci in the colons of operated animals, we did not observe statistically significant differences in any of the distal, proximal and medium fragments, or in all fragments together (p=1.0000). Conclusion: Although statistically there was no promotion of carcinogenesis in the epithelia of rats treated with L-lysine in the observed time, it was clear the histogenesis of bladder carcinogenesis in its initial phase in all operated rats, this being probably associated with chronic infection and tiny bladder stones.


RESUMO Objetivo: o objetivo deste trabalho é avaliar o efeito da L-lisina nos epitélios vesical e intestinal de ratas submetidas à vesicossigmoidostomia. Métodos: quarenta ratas Wistar, foram divididas em quatro grupos: grupo I- grupo controle (Sham); grupo II- submetido à vesicossigmoidostomia e tratado com L-lisina 150mg/kg; grupo III- submetido apenas à vesicossigmoidostomia; e grupo IV- recebeu L-lisina 150mg/kg. Após oito semanas os animais foram sacrificados. Resultados: na bexiga de todos os animais operados observou-se hiperplasia simples, papilar e nodular de células transicionais, papiloma de células transicionais e metaplasia escamosa. Quanto à ocorrência de focos de criptas aberrantes nos colos dos animais operados, não foi evidenciado diferença estatística significante em nenhum dos fragmentos distal, proximal e médio, e todos juntos (P=1,0000). Conclusão: apesar de, estatisticamente, não ter havido promoção de carcinogênese nos epitélios dos ratos tratados com L-lisina, no tempo observado, é nítida a histogênese da carcinogênese de bexiga em sua fase inicial, no epitélio vesical, em todos os ratos operados, estando esta provavelmente associada à infecção crônica e aos diminutos cálculos vesicais.


Assuntos
Animais , Ratos , Complicações Pós-Operatórias/induzido quimicamente , Colo Sigmoide/cirurgia , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/patologia , Ureterostomia , Carcinogênese/induzido quimicamente , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Lisina/farmacologia , Ratos Wistar
17.
Fractal rev. psicol ; 26(2): 429-444, May-Aug/2014. tab
Artigo em Português | LILACS | ID: lil-721443

RESUMO

Esse estudo analisou como jovens de escolas públicas identificam e avaliam vivências de violência no ambiente familiar e comunitário, partindo de um recorte de uma pesquisa sobre risco e proteção na população juvenil. Para tanto, foram selecionados 529 estudantes, de 14 a 24 anos e ambos os sexos, que afirmaram ter sofrido algum tipo de violência naqueles ambientes. Aplicou-se um instrumento com 77 questões sobre situações cotidianas e fez-se análise dos itens relativos à vivência de situações de violência. Os resultados demonstraram a ocorrência mais frequente de violência física na família. Já, na comunidade, ameaça ou humilhação. A percepção negativa dos jovens sobre o ambiente de ocorrência da violência, destacou-se o familiar. Os dados sobre autoestima e auto eficácia revelaram aspectos protetivos. As análises conduzem à conclusão de que a percepção da violência como fator de risco precisa ser compreendida no contexto de participação do jovem e na sua história.


This research analyzes how public school students identify and evaluate experiences of violence in a domestic environment and within their communities. This is a snip of a larger research on risk and protective factors in youth populations. Of the 1.140 participants, 529 were students from both genders with ages between 14 and 24. The results revealed that punching and spanking occurred more frequently in the familiar environment, whereas threatening and humiliation within the community. It was applied a survey with 77 questions concerning those experiences in everyday situations. As for the negative perceptions on the types of abuse regarding the environment where they occurred, the study indicates that undergoing domestic violence had a stronger impact. The results on self-esteem and self-efficacy revealed protective aspects of personal nature. The perception of violence as a risk factor should be understood based on the context of the subject's role and their life story.


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adolescente , Violência Doméstica , Fatores de Proteção , Fatores de Risco , Estudantes , Violência
18.
Fractal rev. psicol ; 26(2): 429-444, maio-ago. 2014. tab
Artigo em Português | Index Psi (psicologia) | ID: psi-64399

RESUMO

Esse estudo analisou como jovens de escolas públicas identificam e avaliam vivências de violência no ambiente familiar e comunitário, partindo de um recorte de uma pesquisa sobre risco e proteção na população juvenil. Para tanto, foram selecionados 529 estudantes, de 14 a 24 anos e ambos os sexos, que afirmaram ter sofrido algum tipo de violência naqueles ambientes. Aplicou-se um instrumento com 77 questões sobre situações cotidianas e fez-se análise dos itens relativos à vivência de situações de violência. Os resultados demonstraram a ocorrência mais frequente de violência física na família. Já, na comunidade, ameaça ou humilhação. A percepção negativa dos jovens sobre o ambiente de ocorrência da violência, destacou-se o familiar. Os dados sobre autoestima e autoeficácia revelaram aspectos protetivos. As análises conduzem à conclusão de que a percepção da violência como fator de risco precisa ser compreendida no contexto de participação do jovem e na sua história.(AU)


This research analyzes how public school students identify and evaluate experiences of violence in a domestic environment and within their communities. This is a snip of a larger research on risk and protective factors in youth populations. Of the 1.140 participants, 529 were students from both genders with ages between 14 and 24. The results revealed that punching and spanking occurred more frequently in the familiar environment, whereas threatening and humiliation within the community. It was applied a survey with 77 questions concerning those experiences in everyday situations. As for the negative perceptions on the types of abuse regarding the environment where they occurred, the study indicates that undergoing domestic violence had a stronger impact. The results on self-esteem and self-efficacy revealed protective aspects of personal nature. The perception of violence as a risk factor should be understood based on the context of the subject's role and their life story.(AU)


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Violência Doméstica , Violência , Adolescente , Fatores de Risco , Fatores de Proteção , Estudantes
19.
Psicol. teor. prat ; 10(2): 147-161, dez. 2008.
Artigo em Português | Index Psi (psicologia) | ID: psi-48232

RESUMO

Este artigo tematiza articulações teórico-metodológicas entre a Psicologia Comunitária e a Educação Libertadora, discutindo também suas propostas socioideológicas e ético-políticas. Consiste em um desdobramento de uma pesquisa realizada pelo Núcleo de Psicologia Comunitária (Nucom) da Universidade Federal do Ceará, cuja finalidade era contribuir com o desenvolvimento epistemológico do marco teórico-metodológico da Psicologia Comunitária. Para tanto, procedemos a uma revisão teórica, explorando, na trajetória de constituição da Educação Libertadora e da Psicologia Comunitária, o encontro entre ambas as teorias, especificamente no Estado do Ceará. Tal revisão se debruçou ainda sobre elementos teórico-metodológicos, identificando pontos de convergência e integração entre ambas as disciplinas, bem como os fundamentos socioideológicos que refletem sua visão de mundo. Assim, apontamos para uma significativa consistência epistemológica relativa à integração da Educação Libertadora no marco teórico da Psicologia Comunitária, conferindo coesão teórico-metodológica e coerência ético-política a essa práxis psicológica libertadora, a partir do eixo teoria-prática-compromisso social.(AU)


This paper is about the theorical methodological links between Community Psychology and Liberating Education, discussing their social ideological and ethical political proposals. It concerns an unfolding of a research conducted by the Núcleo de Psicologia Comunitária (Nucom) of the Universidade Federal do Ceará (UFC), with the intention of contributing to the epistemological development of the theorical methodological milestone of the Community Psychology. In order to reach this aim, we made a theorical revision, exploring, in the trajectory of the constitution of Liberating Education and Community Psychology, the meeting of both theories, specifically in the Ceará state. This review is also based on theorical methodological elements that identify points of convergences and integration between both disciplines, as well as the social ideological foundations which reflect their view of the world. So, we point to a relevant epistemological consistency related to the integration of Liberating Education in the theorical milestone of Community Psychology, giving theorical methodological cohesion and ethical political coherence to this liberating psychological praxis, in the axis of theory, praxis and social compromise.(AU)


Este artículo tematiza articulaciones teórico-metodológicas entre la Psicología Comunitaria y la Educación Libertadora, discutiendo también sus propuestas socio-ideológicas y ético-políticas. Consiste en un desdobramiento de una investigación realizada por el Núcleo de Psicología Comunitaria (Nucom) de la Universidad Federal de Ceará, cuya finalidad fué contribuir con el desarrollo epistemológico del marco teórico-metodológico de la Psicología Comunitaria. Para tanto, se procedió con una revisión teórica, explorando en la trayectoria de constitución de la Educación Libertadora y de la Psicología Comunitaria el encuentro entre las dos teorías, especificamente en el estado de Ceará. Tal revisión se foco también sobre elementos teórico-metodológicos, identificando puntos de convergencia e integración entre las dos disciplinas, bien como a los fundamentos sócio- ideológicos que reflejan su visión de mundo. Así, apuntamos para una significativa consistencia epistemológica relativa a la integración de la Educación Libertadora en el marco teórico de la Psicología Comunitaria, confiriéndole coesión teórico-metodológica y coherencia ético-política a esa praxis psicológica libertadora, a partir del eje teoría-práctica-compromiso social.(AU)


Assuntos
Psicologia , Educação , Conhecimento
20.
Psicol. teor. prát ; 10(2): 147-161, dez. 2008.
Artigo em Português | LILACS | ID: lil-519638

RESUMO

Este artigo tematiza articulações teórico-metodológicas entre a Psicologia Comunitária e a Educação Libertadora, discutindo também suas propostas socioideológicas e ético-políticas. Consiste em um desdobramento de uma pesquisa realizada pelo Núcleo de Psicologia Comunitária (Nucom) da Universidade Federal do Ceará, cuja finalidade era contribuir com o desenvolvimento epistemológico do marco teórico-metodológico da Psicologia Comunitária. Para tanto, procedemos a uma revisão teórica, explorando, na trajetória de constituição da Educação Libertadora e da Psicologia Comunitária, o encontro entre ambas as teorias, especificamente no Estado do Ceará. Tal revisão se debruçou ainda sobre elementos teórico-metodológicos, identificando pontos de convergência e integração entre ambas as disciplinas, bem como os fundamentos socioideológicos que refletem sua visão de mundo. Assim, apontamos para uma significativa consistência epistemológica relativa à integração da Educação Libertadora no marco teórico da Psicologia Comunitária, conferindo coesão teórico-metodológica e coerência ético-política a essa práxis psicológica libertadora, a partir do eixo teoria-prática-compromisso social.


This paper is about the theorical methodological links between Community Psychology and Liberating Education, discussing their social ideological and ethical political proposals. It concerns an unfolding of a research conducted by the Núcleo de Psicologia Comunitária (Nucom) of the Universidade Federal do Ceará (UFC), with the intention of contributing to the epistemological development of the theorical methodological milestone of the Community Psychology. In order to reach this aim, we made a theorical revision, exploring, in the trajectory of the constitution of Liberating Education and Community Psychology, the meeting of both theories, specifically in the Ceará state. This review is also based on theorical methodological elements that identify points of convergences and integration between both disciplines, as well as the social ideological foundations which reflect their view of the world. So, we point to a relevant epistemological consistency related to the integration of Liberating Education in the theorical milestone of Community Psychology, giving theorical methodological cohesion and ethical political coherence to this liberating psychological praxis, in the axis of theory, praxis and social compromise.


Este artículo tematiza articulaciones teórico-metodológicas entre la Psicología Comunitaria y la Educación Libertadora, discutiendo también sus propuestas socio-ideológicas y ético-políticas. Consiste en un desdobramiento de una investigación realizada por el Núcleo de Psicología Comunitaria (Nucom) de la Universidad Federal de Ceará, cuya finalidad fué contribuir con el desarrollo epistemológico del marco teórico-metodológico de la Psicología Comunitaria. Para tanto, se procedió con una revisión teórica, explorando en la trayectoria de constitución de la Educación Libertadora y de la Psicología Comunitaria el encuentro entre las dos teorías, especificamente en el estado de Ceará. Tal revisión se foco también sobre elementos teórico-metodológicos, identificando puntos de convergencia e integración entre las dos disciplinas, bien como a los fundamentos sócio- ideológicos que reflejan su visión de mundo. Así, apuntamos para una significativa consistencia epistemológica relativa a la integración de la Educación Libertadora en el marco teórico de la Psicología Comunitaria, confiriéndole coesión teórico-metodológica y coherencia ético-política a esa praxis psicológica libertadora, a partir del eje teoría-práctica-compromiso social.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa