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1.
Biomater Biosyst ; 14: 100094, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38596510

RESUMO

Spatial cell organization and biofabrication of microcapillary networks in vitro has a great potential in tissue engineering and regenerative medicine. This study explores the impact of local cell density enhancement achieved through an innovative sound-based patterning on microcapillary networks formation and their proteomic profile. Human umbilical vein endothelial cells (HUVEC) and human pericytes from placenta (hPC-PL) were mixed in a fibrin suspension. The mild effect of sound-induced hydrodynamic forces condensed cells into architected geometries showing good fidelity to the numerical simulation of the physical process. Local cell density increased significantly within the patterned areas and the capillary-like structures formed following the cell density gradient. Over five days, these patterns were well-maintained, resulting in concentric circles and honeycomb-like structures. Proteomic analysis of the pre-condensed cells cultured for 5 days, revealed over 900 differentially expressed proteins when cells were preassembled through mild-hydrodynamic forces. Gene ontology (GO) enrichment analysis identified cellular components, molecular functions, and biological processes that were up- and down-regulated, providing insights regarding molecular processes influenced by the local density enhancement. Furthermore, we employed Ingenuity Pathway Analysis (IPA) to identify altered pathways and predict upstream regulators. Notably, VEGF-A emerged as one of the most prominent upstream regulators. Accordingly, this study initiates the unraveling of the changes in microcapillary networks at both molecular and proteins level induced by cell condensation obtained through sound patterning. The findings provide valuable insights for further investigation into sound patterning as a biofabrication technique for creating more complex microcapillary networks and advancing in vitro models.

2.
Sci Total Environ ; 884: 163720, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37137361

RESUMO

Microplastic particles (MP) are emerging pollutants ubiquitously distributed in all aquatic environments, remaining in suspension in the water column or deposited in sediment beds. MP are suspended in the water column along with other particles with whom they might interact. The current study presents the results of slow-settling MP (Polystyrene) scavenged by fast-settling sediment particles. The study covers a wide range of salinities (from freshwater to saltwater) and shear rates (from calm to mixing ecosystems). In calm regions, the scavenging by fast-settling sediment particles produces the greatest removal of MP from the water column (42 % of MP in suspension), thus increasing the MP pollution of sediment beds. In contrast, turbulence reduces the settling of MP and sediment particles (72 % of MP remain in suspension), causing more pollution than in calm regions. Although salinity increased the buoyancy of MP, the scavenging by sediment has been found to overcome the increase in buoyancy. Consequently, MP are transported to the sediment bed independently on the salinity. Therefore hotspots of MP contamination in aquatic environments need to consider both the MP and sediment interaction and the local mixing of the water column.


Assuntos
Microplásticos , Poluentes Químicos da Água , Poliestirenos , Plásticos , Ecossistema , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Água
3.
Acta Ortop Mex ; 37(4): 227-323, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38373733

RESUMO

The study intended to evaluate the incidence and evolution of sacroiliac joint dysfunction (SIJD). To reach 50 patients with SIJD diagnosis, 192 patients with low back pain and failure in conservative approach were consecutively examined (26% incidence). Initially patients underwent intra-articular (IA) corticosteroid sacroiliac joint (SIJ) block followed, if necessary, by cooled SIJ radiofrequency or referred to surgical intervention, in order of complexity. From the 50 patients submitted to IA SI block, 41 (82%) referred pain and quality of life improvement and lesser rescue analgesics consumption for 25 weeks. The block induced a prompt onset of pain relief and there was a drop in mean pain score from 8 to 2 cm (p < 0.001) maintained up to 25 weeks. Rescue analgesic consumption also significantly dropped (p < 0.05). However, nine patients (18%) did not refer long lasting improvement in the third week evaluation and underwent cooled radiofrequency. From this population of nine, seven were successful (78%) while two were recommended surgery. In view of the 50 patients, 82% were comfortable after IA block, 18% were submitted to radiofrequency, with a success rate of 78%. The final incidence of surgery suggestion was 4%.


El estudio pretende evaluar la incidencia y evolución de la disfunción de la articulación sacroilíaca (DASI). Para llegar a 50 pacientes con diagnóstico de DASI, se examinaron consecutivamente 192 pacientes con dolor lumbar y fracaso en el abordaje conservador (26% de incidencia). Inicialmente, los pacientes se sometieron a un bloqueo de la articulación sacroilíaca (ASI) con corticosteroides intraarticulares (IA) seguido, si era necesario, de radiofrecuencia ASI enfriada o remitidos a una intervención quirúrgica, en orden de complejidad. De los 50 pacientes sometidos al bloqueo IA SI, 41 (82%) refirieron mejoría del dolor y de la calidad de vida y menor consumo de analgésicos de rescate durante 25 semanas. El bloqueo indujo un rápido inicio del alivio del dolor y hubo una caída en la puntuación media del dolor de 8 a 2 cm (p < 0.001) mantenida hasta 25 semanas. El consumo de analgésicos de rescate también disminuyó significativamente (p < 0.05). Sin embargo, nueve pacientes (18%) no refirieron una mejoría duradera en la evaluación de la tercera semana y se sometieron a radiofrecuencia fría. De esta población de nueve, siete tuvieron éxito (78%), mientras que a dos se les recomendó cirugía. De los 50 pacientes, 82% se sintió cómodo después del bloqueo IA, 18% fue sometido a radiofrecuencia, con una tasa de éxito de 78%. La incidencia final de sugerencia de cirugía fue de 4%.


Assuntos
Artropatias , Dor Lombar , Humanos , Dor Lombar/epidemiologia , Dor Lombar/etiologia , Dor Lombar/terapia , Articulação Sacroilíaca/cirurgia , Brasil , Qualidade de Vida
4.
Rev Med Chil ; 140(3): 340-6, 2012 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-22689114

RESUMO

BACKGROUND: The International Consultation on Incontinence Questionnaire Short-Form (ICIQ-SF) allows the assessment of urinary incontinence management results. AIM: To validate the ICIQ-SF in a Chilean population. MATERIAL AND METHODS: An approved Spanish version of the ICIQ-SF was applied in two opportunities (separated by a mean of 44 days) to 52 women consulting for urinary incontinence in a public hospital and to 25 asymptomatic female workers of the same hospital. Content validity, internal consistency and construct validity of the ICIQ-SF were evaluated. RESULTS: The ages of surveyed women ranged from 21 to 80 years. Internal consistency measured using Cronbach alpha was 0.87. Intra observer agreement, measured using pondered Kappa, was 0.84. 0.86 and 0.8 for each of the three components of the questionnaire, respectively. CONCLUSIONS: This Spanish version of the ICIQ-SF meets the requirements to be used in the Chilean population.


Assuntos
Inquéritos e Questionários , Incontinência Urinária/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Chile , Feminino , Humanos , Idioma , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Traduções , Adulto Jovem
5.
Mater Today Bio ; 10: 100110, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33997761

RESUMO

Novel approaches, combining technology, biomaterial design, and cutting-edge cell culture, have been increasingly considered to advance the field of tissue engineering and regenerative medicine. Within this context, acoustic manipulation to remotely control spatial cellular organization within a carrier matrix has arisen as a particularly promising method during the last decade. Acoustic or sound-induced manipulation takes advantage of hydrodynamic forces exerted on systems of particles within a liquid medium by standing waves. Inorganic or organic particles, cells, or organoids assemble within the nodes of the standing wave, creating distinct patterns in response to the applied frequency and amplitude. Acoustic manipulation has advanced from micro- or nanoparticle arrangement in 2D to the assembly of multiple cell types or organoids into highly complex in vitro tissues. In this review, we discuss the past research achievements in the field of acoustic manipulation with particular emphasis on biomedical application. We survey microfluidic, open chamber, and high throughput devices for their applicability to arrange non-living and living units in buffer or hydrogels. We also investigate the challenges arising from different methods, and their prospects to gain a deeper understanding of in vitro tissue formation and application in the field of biomedical engineering.

6.
Diagn Interv Imaging ; 101(10): 649-655, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32654985

RESUMO

PURPOSE: To analyze the relationships between background parenchymal enhancement (BPE) of the contralateral healthy breast and tumor response after neoadjuvant chemotherapy (NAC) in women with breast cancer. MATERIALS AND METHODS: A total of 228 women (mean age, 47.6 years±10 [SD]; range: 24-74 years) with invasive breast cancer who underwent NAC were included. All patients underwent breast magnetic resonance imaging (MRI) before and after NAC and 127 patients underwent MRI before, during (after the 4th cycle of NAC) and after NAC. Quantitative semi-automated analysis of BPE of the contralateral healthy breast was performed. Enhancement level on baseline MRI (baseline BPE) and MRI after chemotherapy (final BPE), change in enhancement rate between baseline MRI and final MRI (total BPE change) and between baseline MRI and midline MRI (early BPE change) were recorded. Associations between BPE and tumor response, menopausal status, tumor phenotype, NAC type and tumor stage at diagnosis were searched for. Pathologic complete response (pCR) was defined as the absence of residual invasive cancer cells in the breast and ipsilateral lymph nodes. RESULTS: No differences were found in baseline BPE, final BPE, early and total BPE changes between pCR and non-pCR groups. Early BPE change was higher in non-pCR group in patients with stages 3 and 4 breast cancers (P=0.019) and in human epidermal growth factor receptor 2 (HER2)-negative patients (P=0.020). CONCLUSION: Early reduction of BPE in the contralateral breast during NAC may be an early predictor of loss of tumor response, showing potential as an imaging biomarker of treatment response, especially in women with stages 3 or 4 breast cancers and in HER2 - negative breast cancers.


Assuntos
Neoplasias da Mama , Terapia Neoadjuvante , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Estudos Retrospectivos
7.
Br J Dermatol ; 161(2): 320-5, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19500101

RESUMO

BACKGROUND: Leishmaniasis is a parasitic disease prevalent in countries of the Mediterranean area. OBJECTIVES: The potential role of Leishmania as the aetiological factor for cutaneous granulomatous lesions in a series of patients from a Western Mediterranean area was evaluated. The practical usefulness of Leishmania-specific polymerase chain reaction (PCR) amplification and immunohistochemical techniques in skin biopsy specimens was assessed. METHODS: Twenty-five skin biopsies diagnosed as nonspecific granulomatous dermatoses were included in the study. A panel of histopathological features was blindly evaluated by two independent observers. Only those cases showing nondiagnostic clinicopathological features and lacking demonstrable microorganisms after bacteriological, mycological or mycobacteriological cultures and specific stains (Ziehl-Neelsen, Giemsa, Gram, periodic acid-Schiff stains) were finally selected. Quantitative real-time PCR was performed in all selected samples. In available samples, immunohistochemical detection of specific Leishmania spp. antigens was also performed. RESULTS: From the selected 25 biopsies, Leishmania spp. DNA was detected by real-time PCR in 13 cases. In seven of eight PCR-positive cases the presence of a varying density of amastigotes could also be demonstrated immunohistochemically. CONCLUSIONS: Leishmania infection seems to be an important aetiological factor in cutaneous granulomatous lesions showing nondiagnostic features in endemic areas. In such areas, Leishmania-specific PCR amplification and/or immunohistochemical studies may be useful diagnostic tools. These techniques may be specifically indicated in the evaluation of patients showing nonspecific granulomatous inflammatory infiltrates of unknown aetiology lacking the histopathological evidence of parasites.


Assuntos
Granuloma/parasitologia , Leishmaniose Cutânea/parasitologia , Pele/parasitologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Biópsia , Pré-Escolar , DNA de Protozoário/análise , Diagnóstico Diferencial , Feminino , Granuloma/patologia , Humanos , Imuno-Histoquímica , Leishmania/genética , Leishmania/isolamento & purificação , Leishmaniose Cutânea/patologia , Masculino , Região do Mediterrâneo , Pessoa de Meia-Idade , Estudos Retrospectivos , Pele/patologia , Adulto Jovem
8.
Radiat Res ; 189(5): 541-547, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29547352

RESUMO

We investigated the association between environmental exposure to radiofrequency electromagnetic fields (RF-EMF) and risk of lymphoma subtypes in a case-control study comprised of 322 patients and 444 individuals serving as controls in Sardinia, Italy in 1998-2004. Questionnaire information included the self-reported distance of the three longest held residential addresses from fixed radio-television transmitters and mobile phone base stations. We georeferenced the residential addresses of all study subjects and obtained the spatial coordinates of mobile phone base stations. For each address within a 500-meter radius from a mobile phone base station, we estimated the RF-EMF intensity using predictions from spatial models, and we performed RF-EMF measurements at the door in the subset of the longest held addresses within a 250-meter radius. We calculated risk of lymphoma and its major subtypes associated with the RF-EMF exposure metrics with unconditional logistic regression, adjusting by age, gender and years of education. In the analysis of self-reported data, risk associated with residence in proximity (within 50 meters) to fixed radio-television transmitters was likewise elevated for lymphoma overall [odds ratio = 2.7, 95% confidence interval = 1.5-4.6], and for the major lymphoma subtypes. With reference to mobile phone base stations, we did not observe an association with either the self-reported, or the geocoded distance from mobile phone base stations. RF-EMF measurements did not vary by case-control status. By comparing the self-reports to the geocoded data, we discovered that the cases tended to underestimate the distance from mobile phone base stations differentially from the controls ( P = 0.073). The interpretation of our findings is compromised by the limited study size, particularly in the analysis of the individual lymphoma subtypes, and the unavailability of the spatial coordinates of radio-television transmitters. Nonetheless, our results do not support the hypothesis of a link between environmental exposure to RF-EMF from mobile phone base stations and risk of lymphoma subtypes.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Linfoma/etiologia , Neoplasias Induzidas por Radiação/etiologia , Exposição à Radiação/efeitos adversos , Ondas de Rádio/efeitos adversos , Adulto , Idoso , Estudos de Casos e Controles , Telefone Celular , Feminino , Humanos , Linfoma/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/epidemiologia , Medição de Risco
9.
Food Chem ; 210: 558-65, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27211682

RESUMO

Opuntia spp. fruits are considered as health promoting foods due to the diversity of bioactive molecules found in these fruits. The composition in organic acids, flavonols and betalains in the Opuntia ficus-indica juice from a region of Portugal was accomplished for the first time by liquid chromatography and tandem mass spectrometry using an electrospray ionization source operating in negative and positive mode. The methodology used allowed the detection of 44 compounds, from which 32 were identified. Isorhamnetin derivatives were the dominant flavonol glycosides. A total of 9 betalains including 6 betaxanthins and 3 betacyanin were also detected in the fruit juice samples and indicaxanthin, betanin and isobetanin were the major pigments. Phenolic acid and phenylpyruvic acid derivatives were also identified. To our knowledge, it is the first time derivative compounds from piscidic acid, phenolic compounds and betalains are characterized in cactus pear juice using a single LC-DAD-ESI-MS/MS method.


Assuntos
Bebidas/análise , Cromatografia Líquida/métodos , Frutas/química , Opuntia/química , Espectrometria de Massas em Tandem/métodos , Betacianinas/análise , Betaxantinas/análise , Flavonóis/análise , Fenóis/análise , Extratos Vegetais/química , Portugal , Piridinas/análise , Quercetina/análogos & derivados , Quercetina/análise , Espectrometria de Massas por Ionização por Electrospray
10.
Biofabrication ; 8(3): 035001, 2016 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-27431399

RESUMO

Spinal fusion is the gold standard surgical procedure for degenerative spinal conditions when conservative therapies have been unsuccessful in rehabilitation of patients. Novel strategies are required to improve biocompatibility and osseointegration of traditionally used materials for lumbar cages. Furthermore, new design and technologies are needed to bridge the gap due to the shortage of optimal implant sizes to fill the intervertebral disc defect. Within this context, additive manufacturing technology presents an excellent opportunity to fabricate ergonomic shape medical implants. The goal of this study is to design and manufacture a 3D-printed lumbar cage for lumbar interbody fusion. Optimisations of the proposed implant design and its printing parameters were achieved via in silico analysis. The final construct was characterised via scanning electron microscopy, contact angle, x-ray micro computed tomography (µCT), atomic force microscopy, and compressive test. Preliminary in vitro cell culture tests such as morphological assessment and metabolic activities were performed to access biocompatibility of 3D-printed constructs. Results of in silico analysis provided a useful platform to test preliminary cage design and to find an optimal value of filling density for 3D printing process. Surface characterisation confirmed a uniform coating of nHAp with nanoscale topography. Mechanical evaluation showed mechanical properties of final cage design similar to that of trabecular bone. Preliminary cell culture results showed promising results in terms of cell growth and activity confirming biocompatibility of constructs. Thus for the first time, design optimisation based on computational and experimental analysis combined with the 3D-printing technique for intervertebral fusion cage has been reported in a single study. 3D-printing is a promising technique for medical applications and this study paves the way for future development of customised implants in spinal surgical applications.


Assuntos
Materiais Biocompatíveis , Impressão Tridimensional , Próteses e Implantes , Fusão Vertebral/instrumentação , Estresse Mecânico , Tecido Adiposo/citologia , Força Compressiva , Simulação por Computador , Humanos , Microscopia de Força Atômica , Modelos Biológicos , Células-Tronco/fisiologia
11.
Plant Signal Behav ; 11(8): e1208880, 2016 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-27467198

RESUMO

Plant development depends on the perception of external cues, such as light, gravity, touch, wind or nutrients, among others. Nevertheless, little is known regarding signal transduction pathways integrating these stimuli. Recently, we have reported the involvement of a rice E3-ubiquitin ligase (OsHOS1, HIGH EXPRESSION OF OSMOTICALLY RESPONSIVE GENE1), previously associated with abiotic stress response, in root responses to mechanical stimuli. We showed that OsHOS1 is involved in the regulation of root curling after mechanosensing and that RNAi::OsHOS1 plants failed to exhibit the root curling phenotype observed in WT. Interestingly, the straight root phenotype of these transgenics correlated with the up-regulation of rice ROOT MEANDER CURLING (OsRMC, a negative regulator of rice root curling) and was reverted by the exogenous application of jasmonic acid. Altogether, our results highlight the role of the proteasome modulating plant responses to mechanical stimuli and suggest that OsHOS1 is a hub integrating environmental and hormonal signaling into plant growth and development.


Assuntos
Oryza/metabolismo , Raízes de Plantas/metabolismo , Ciclopentanos/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Mecanotransdução Celular/efeitos dos fármacos , Oryza/efeitos dos fármacos , Oryza/enzimologia , Oxilipinas/farmacologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/enzimologia , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
12.
Arq. bras. med. vet. zootec. (Online) ; 72(6): 2223-2232, Nov.-Dec. 2020. tab, graf, ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-1142318

RESUMO

O objetivo deste estudo foi avaliar o efeito da ω-conotoxina MVIIC e das células-tronco mesenquimais (CTM) de forma isolada e sua associação nos ratos submetidos ao trauma medular agudo (TMA). Trinta Rattus novergicus, linhagem Wistar, três meses de idade, foram distribuídos igualmente em cinco grupos experimentais: controle negativo (CN), controle positivo (CP), ω-conotoxina MVIIC (MVIIC), células-tronco mesenquimais da medula óssea (CTM-MO) e associação (MVIIC + CTM-MO). O grupo CN foi submetido à laminectomia sem trauma medular, e os grupos CP, MVIIC, CTM-MO e MVIIC + CTM-MO foram submetidos ao trauma medular contusivo. O grupo CP recebeu, uma hora após o TMA, 10µL de PBS estéril, e os grupos MVIIC e MVIIC + CTM-MO receberam 10µL de PBS contendo 20pmol da ω-conotoxina MVIIC, todos por via intratecal. Os grupos CTM-MO e MVIIC + CTM-MO receberam, 24 horas após, 1x106 de CTM via intravenosa. Avaliou-se a recuperação da função locomotora até o sétimo dia pós-trauma. Os animais tratados com MVIIC + CTM-MO obtiveram recuperação motora após o trauma medular agudo (P<0,05). Conclui-se que essa associação apresentou efeito neuroprotetor com melhora na função locomotora em ratos Wistar.(AU)


The objective of this study was to evaluate the effect of isolated ω-conotoxin MVIIC and mesenchymal stem cells (MSCs) and its association in rats submitted to acute spinal cord injury (SCI). Thirty Rattus norvegicus, Wistar strain, three-month-old rats were randomly distributed in five experimental groups with six animals: negative control (CN), positive control (CP), ω-conotoxin MVIIC (MVIIC), bone marrow mesenchymal stem cells (CTM-MO) and the association (MVIIC + CTM-MO). The CN group underwent laminectomy without spinal cord trauma, and groups CP, MVIIC, CTM-MO and MVIIC + CTM-MO were submitted to contusive spinal cord trauma. The CP group received 10µl of PBS one hour after SCI, and groups MVIIC and MVIIC + CTM-MO received 10µl of PBS containing 20pmol of ω-conotoxin MVIIC, both intrathecally. Groups CTM-MO and MVIIC + CTM-MO received 1x106 of MSCs intravenously 24 hours later. The recovery of locomotor function was evaluated up to seven days post-injury. The animals treated with MVIIC + CTM-MO obtained motor recovery after SCI (P<0.05). It is concluded that this association showed neuroprotective effect with improvements in locomotor function in Wistar rats.(AU)


Assuntos
Animais , Ratos , Traumatismos da Medula Espinal/reabilitação , Bloqueadores dos Canais de Cálcio , ômega-Conotoxinas/uso terapêutico , Células-Tronco Mesenquimais , Terapia Baseada em Transplante de Células e Tecidos/veterinária , Neuroproteção , Ratos Wistar
13.
Eur J Cell Biol ; 43(2): 247-52, 1987 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3595635

RESUMO

The ultrastructural and biochemical alterations produced by an hypocholesterolemic drug, 17 alpha-ethinyl estradiol, on the rat adrenal cortex were studied. Male rats aged two months and with approximately 200 g in weight were injected subcutaneously with 10 mg/kg/day of ethinyl estradiol during 9 days; rats injected with 1 ml propylene glycol were used as controls. The animals were sacrificed on the 10th day, and the adrenals from some of them were processed for electron microscopy. The adrenals from the remaining rats were used for measurements of the glands cholesterol and corticosterone, which were also measured in the blood. In estradiol-treated rats the zona fasciculata cells exhibited numerous microvilli, increase in the size of mitochondria and decrease in the number of lipid droplets. The quantitative analysis showed a significant increase of the volumetric density of mitochondria and microvilli and a significant decrease of the lipid droplets in the treated rats, when compared with normal ones. In treated rats, the concentration of cholesterol and corticosterone in the gland and blood were significantly decreased. These data show that hypocholesterolemia produced by estradiol has a remarkable effect on adrenal steroidogenesis, depletes the pool of adrenal cholesteryl esters, and evidences the role of plasma cholesterol in the corticosteroidogenesis.


Assuntos
Córtex Suprarrenal/metabolismo , Colesterol/metabolismo , Corticosterona/metabolismo , Etinilestradiol/farmacologia , Córtex Suprarrenal/efeitos dos fármacos , Córtex Suprarrenal/ultraestrutura , Animais , Ésteres do Colesterol/metabolismo , Masculino , Microscopia Eletrônica , Ratos , Ratos Endogâmicos
14.
Trans R Soc Trop Med Hyg ; 96 Suppl 1: S93-9, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12055859

RESUMO

In the Mediterranean basin, Leishmania infantum is the causative agent of both visceral and cutaneous leishmaniasis, and is an important opportunistic parasite in patients infected with human immunodeficiency virus (HIV). The commonest method used to study the variability of Leishmania spp. is isoenzyme analysis. In addition to this, we employed 3 assays based on the polymerase chain reaction (PCR): random amplified polymorphic deoxyribonucleic acid (RAPD), intergenic region typing (IRT), based on the amplification of ribosomal ribonucleic acid internal transcribed spacers and restriction fragment length polymorphism (PCR-RFLP). We used 54 L. infantum stocks isolated from HIV co-infected patients, 38 isolated from dogs, 3 isolated from immunocompetent patients and 3 isolated from 1826 sand files in the island of Majorca (Spain), a closed ecological niche. Zymodemes MON-1 (70%), MON-24 (11%) and MON-34 (18%) were found among the human isolates, and MON-1 (95%) and MON-108 (5%) among those from dogs. RAPD and IRT could not discriminate among the strains as they all gave the same pattern, even when different zymodemes were examined. In contrast, PCR-RFLP was able to distinguish the strains and, furthermore, a dendrogram (unweighted pair group method with arithmetic average [UPGMA]) was constructed from the genetic distances derived from RFLP data. The Leishmania isolates from HIV-infected subjects formed a single cluster, supporting the existence of an artificial anthroponotic cycle previously proposed by our group, in which syringes have been substituted for sand flies, and in which certain clones have been spread among intravenous drug users. This contrasts with the clusters representing a zoonotic cycle, involving dogs, sand flies and both immunocompetent and immunocompromised humans.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Leishmania infantum/genética , Leishmaniose Visceral/epidemiologia , Animais , DNA de Cinetoplasto/genética , Doenças do Cão/epidemiologia , Cães , Feminino , Genótipo , Humanos , Isoenzimas/análise , Leishmania infantum/classificação , Leishmaniose Visceral/veterinária , Fenótipo , Reação em Cadeia da Polimerase/métodos , Psychodidae/parasitologia , Espanha/epidemiologia
15.
J Pharm Sci ; 65(5): 737-8, 1976 May.
Artigo em Inglês | MEDLINE | ID: mdl-932945

RESUMO

Among other common compounds, pinastric acid and ergosterol were isolated for the first time from Parmelia caperata. The isolation of these compounds is described; identification was made from the melting point and UV, IR, and mass spectral data.


Assuntos
Ergosterol/análise , Líquens/análise , Fenilacetatos/análise , Furanos/análise
16.
Tissue Cell ; 19(2): 167-75, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3495905

RESUMO

Adrenal cells of newborn rat adrenals in primary tissue culture were treated with actinomycin D (2, 10 and 25 micrograms/ml), alpha-amanitin (5 and 50 micrograms/ml) and cordycepin (100 micrograms/ml) and studied with the electron microscope. The most striking changes observed with the three drugs were localized on the nucleoli, and consisted, respectively, of segregation (actinomycin D), fragmentation (alpha-amanitin) and microsegregation (cordycepin). These results are consistent with the molecular sites of action of the drugs and are comparable to previous in vivo findings.


Assuntos
Glândulas Suprarrenais/ultraestrutura , Amanitinas/farmacologia , Dactinomicina/farmacologia , Desoxiadenosinas/farmacologia , Glândulas Suprarrenais/citologia , Glândulas Suprarrenais/efeitos dos fármacos , Animais , Células Cultivadas , Corticosterona/metabolismo , Microscopia Eletrônica , Ratos , Ratos Endogâmicos , Transcrição Gênica/efeitos dos fármacos
17.
Tissue Cell ; 23(2): 209-15, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1853335

RESUMO

The ultrastructural and biochemical changes produced by monensin on zona fasciculata cells of the rat adrenal cortex are described. In this study we used adrenal cells in culture, adrenal slices and the intact animal. Monensin (1 microM) was added to the culture medium containing the cells, and to the incubation medium containing the adrenal slices, and was injected intravenously to the intact animal (0.65 mg/kg body weight). The ultrastructural alterations were similar in the three experimental conditions, and consisted of Golgi complex disorganization with dilated cisternae or large smooth vesicles. Quantitative analysis showed a significant increase of the relative volume of the Golgi area. The biochemical study demonstrated a significant decrease of corticosterone concentrations in culture medium after monensin addition, and in adrenal glands from treated rats. These results showed that monensin alters the fine structure of adrenal cortex Golgi complex and inhibits corticosteroidogenesis, which supports the probable role of the Golgi complex in the regulation of steroidogenesis.


Assuntos
Córtex Suprarrenal/efeitos dos fármacos , Corticosterona/biossíntese , Complexo de Golgi/efeitos dos fármacos , Monensin/farmacologia , Córtex Suprarrenal/metabolismo , Córtex Suprarrenal/ultraestrutura , Animais , Células Cultivadas , Depressão Química , Complexo de Golgi/fisiologia , Ratos , Zona Fasciculada/ultraestrutura
18.
J Vet Diagn Invest ; 9(1): 50-5, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9087925

RESUMO

A dot-enzyme-linked immunosorbent assay (ELISA) using protein A-peroxidase was evaluated as a diagnostic test for canine leishmaniasis. The test results were in agreement with parasitologic diagnosis and indirect immunofluorescence assay results. The sensitivity of the test calculated on 31 dogs with positive parasitologic examination was 90% when a titer of 1/800 was established as a cutoff and 100% when a titer of 1/400 was established. The specificity calculated on the canine population from nonendemic areas was 100% when both titers were established. Nevertheless, in endemic areas titers near the cutoff need careful interpretation. The results of this study demonstrate that dot-ELISA protein A using a bio-dot apparatus is highly suitable for seroepidemiologic field work.


Assuntos
Doenças do Cão , Leishmaniose/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Cães , Doenças Endêmicas/veterinária , Ensaio de Imunoadsorção Enzimática/métodos , Técnica Indireta de Fluorescência para Anticorpo , Leishmania/isolamento & purificação , Leishmaniose/diagnóstico , Leishmaniose/epidemiologia , Linfonodos/parasitologia , Linfonodos/patologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Testes Sorológicos , Espanha/epidemiologia
19.
Vet Parasitol ; 83(2): 87-97, 1999 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10392965

RESUMO

An epidemiological survey of canine leishmaniosis was conducted in the Priorat, a rural region in the Northeast of Spain, for 10 years (1985-1994). Seroprevalence throughout the region, determined by dot-ELISA and IFI, was 10.2% (8-12%). Forty percent of the dogs studied had a low level of anti-Leishmania antibodies, whereas only 50% were seronegative. Only one-third of the seropositive dogs had evident symptoms of the disease. Annual incidence of the disease was 5.7% and the level of endemicity was stable during the study. Four Leishmania zymodemes (MON-1, MON-29, MON-77, MON-105) were present in the focus, and their distribution in the different hosts is discussed. Apart from dogs and foxes, no other reservoir host has been found in the region.


Assuntos
Doenças do Cão/epidemiologia , Leishmania infantum/imunologia , Leishmaniose Visceral/veterinária , Fatores Etários , Animais , Anticorpos Antiprotozoários/sangue , Reservatórios de Doenças , Cães , Eletroforese/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Raposas , Cabras , Incidência , Isoenzimas , Leishmaniose Visceral/epidemiologia , Masculino , Roedores , População Rural , Estudos Soroepidemiológicos , Fatores Sexuais , Ovinos , Espanha/epidemiologia
20.
Clin Ter ; 133(3): 145-50, 1990 May 15.
Artigo em Italiano | MEDLINE | ID: mdl-2142901

RESUMO

The authors report the results obtained in a comparative study of effects of clofibrate and simvastatin. The investigation was carried out on 44 patients with type IIB hypercholesterolemia subdivided into two groups. Throughout the study, patients observed a diet of about 1500 Kcal daily. Thirty days before starting drug treatment, all patients were given a placebo daily, either of the two drugs being administered during the subsequent 30 days. Plasma cholesterol level was examined before starting placebo and before drug treatment and every five days throughout drug treatment. The results obtained showed that both drugs reduced cholesterol plasma level significantly but the reduction obtained with simvastatin was greater than that obtained with clofibrate. The specificity of the use of these drugs in the management of hypercholesterolemia is stressed.


Assuntos
Anticolesterolemiantes/uso terapêutico , Clofibrato/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Lovastatina/análogos & derivados , Idoso , Avaliação de Medicamentos , Feminino , Humanos , Hipercolesterolemia/sangue , Lovastatina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Sinvastatina , Fatores de Tempo
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