Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 164
Filtrar
1.
Physiol Res ; 72(6): 809-818, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38215066

RESUMO

Wound healing is a dynamic process involving different cell types with distinct roles according to the stages of healing. Fibroblasts and stem cells actively participate in tissue regeneration. A proper stimulation could contribute to enhance wound healing process-es. Helichrysum italicum (H. italicum) is a medical plant well described for its pharmacological, antimicrobial, and anti-inflammatory activities. Aim of the present work was to examine the effect of the hydrolat derivate from H. italicum on stem cells isolated from skin and fibroblasts in vitro in presence or absence of tissue damage. The viability and proliferation of all cell types cultured in dif-ferent conditions were analyzed by MTT and BrdU assays. Cell proliferation after wound was analyzed with scratch test. Also, the expression of the main genes involved in tissue repair was evaluated by RT-qPCR analysis. Here we describe the capability of hy-drolat of H. italicum to promote tissue regeneration after scratch test both in stem cells and in fibroblasts. Moreover, the gene ex-pression analysis revealed that, hydrolat of H. italicum is also able to enhance stemness related. In conclusion our results are en-couraging, highlighting novel regenerative properties of hydrolat of H. italicum and paving the way for future application of this wasting product in accelerating wound healing.


Assuntos
Helichrysum , Cicatrização , Pele , Anti-Inflamatórios/farmacologia , Células-Tronco , Fibroblastos/metabolismo
2.
Physiol Res ; 71(4): 539-549, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35899943

RESUMO

About 30 percent of patients diagnosed with myelodysplastic syndromes (MDS) progress to acute myeloid leukemia (AML). The senescence of bone marrow?derived mesenchymal stem cells (BMSCs) seems to be one of the determining factors in inducing this drift. Research is continuously looking for new methodologies and technologies that can use bioelectric signals to act on senescence and cell differentiation towards the phenotype of interest. The Radio Electric Asymmetric Conveyer (REAC) technology, aimed at reorganizing the endogenous bioelectric activity, has already shown to be able to determine direct cell reprogramming effects and counteract the senescence mechanisms in stem cells. Aim of the present study was to prove if the anti-senescence results previously obtained in different kind of stem cells with the REAC Tissue optimization - regenerative (TO-RGN) treatment, could also be observed in BMSCs, evaluating cell viability, telomerase activity, p19ARF, P21, P53, and hTERT gene expression. The results show that the REAC TO-RGN treatment may be a useful tool to counteract the BMSCs senescence which can be the basis of AML drift. Nevertheless, further clinical studies on humans are needed to confirm this hypothesis.


Assuntos
Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Telomerase , Diferenciação Celular , Humanos , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/terapia , Telomerase/metabolismo , Proteína Supressora de Tumor p53/metabolismo
3.
Theriogenology ; 145: 226-230, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31748175

RESUMO

In a previous study, a subset of miRNAs were identified the expression of which increases substantially during the follicle-luteal transition in cattle. Here, we investigated the functional involvement of some of these miRNAs (miR-96, miR-182, miR-132, miR-21, miR-378) by determining whether there is an association in vivo between their expression in the corpus luteum (CL), CL size and progesterone production. The two largest and two smallest CL were collected from 12 donor beef heifers on Day 7 following ovarian super-stimulation (Day 0 = 28-32 h after first standing to be mounted). Additionally, the CL and a plasma sample were collected from 29 recipient heifers on Day 15. Luteal expression of miRNAs and mRNAs, and plasma progesterone concentrations were quantified by RT-qPCR and RIA, respectively. There were no differences in the mean expression of any miRNAs examined or the steroidogenic enzymes, STAR or CYP11A1, between the largest and smallest CL in donor heifers (P > 0.1). In addition, there were no significant correlations of luteal volume or weight with any miRNA, CYP11A1 or STAR in donor heifers. However, a correlation (r ≥ 0.5, P ≤ 0.001) existed between the transcript levels of CYP11A1 and STAR in the CL, as well as between each of those and miR-182 levels. In addition, CYP11A1 abundance was moderately correlated (r ≤ 0.4, P < 0.05) with each of miR-96 and miR-378. In recipient heifers, progesterone levels were moderately correlated with luteal weight (r = 0.41, P = 0.03) but not with the expression of any miRNA, CYP11A1 or STAR (P > 0.1). Moreover, luteal CYP11A1 and STAR were correlated (r = 0.6, P ≤ 0.001) with miR-182 as well as with each other, consistent with data in donor heifers. Finally, both CYP11A1 and STAR were moderately correlated (r ≤ 0.5) with miR-132 and, in the case of STAR, with miR-378. In summary, there was no association between either luteal weight/volume or plasma progesterone concentrations and any of the miRNAs analysed in donor and recipient heifers. However, CYP11A1 and STAR transcript levels were significantly correlated with several miRNAs, most notably miR-182, as well as with each other, in luteal tissues from both donor and recipient heifers. This finding confirms results of previous in vitro studies and, importantly, provides the first in vivo evidence of a role of the miR-183-96-182 cluster in regulating luteal steroidogenesis.


Assuntos
Bovinos , Corpo Lúteo/anatomia & histologia , Corpo Lúteo/fisiologia , Regulação da Expressão Gênica/fisiologia , MicroRNAs/metabolismo , Esteroides/biossíntese , Animais , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Feminino , MicroRNAs/genética , Fosfoproteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
4.
Physiol Res ; 68(Suppl 4): S375-S384, 2019 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-32118467

RESUMO

Adult stem cells are undifferentiated elements able to self-renew or differentiate to maintain tissue integrity. Within this context, stem cells are able to divide in a symmetric fashion, feature characterising all the somatic cells, or in an asymmetric way, which leads daughter cells to different fates. It is worth highlighting that cell polarity have a critical role in regulating stem cell asymmetric division and the proper control of cell division depends on different proteins involved in cell development, differentiation and maintenance of tissue homeostasis. Moreover, the interaction between cells and the extracellular matrix are crucial in influencing cell behavior, included in terms of mechanical properties as cytoskeleton plasticity and remodelling, and membrane tension. Finally, the activation of specific transcriptional program and epigenetic modifications contributes to cell fate determination, through modulation of cellular signalling cascades. It is well known that physical and mechanical stimuli are able to influence biological systems, and in this context, the effects of electromagnetic fields (EMFs) have already shown a considerable role, even though there is a lack of knowledge and much remains to be done around this topic. In this review, we summarize the historical background of EMFs applications and the main molecular mechanism involved in cellular remodelling, with particular attention to cytoskeleton elasticity and cell polarity, required for driving stem cell behavior.


Assuntos
Células-Tronco Adultas/fisiologia , Polaridade Celular , Campos Eletromagnéticos , Animais , Membrana Celular/fisiologia , Citoesqueleto/fisiologia , Epigênese Genética , Humanos
5.
Physiol Res ; 68(Suppl 4): S385-S388, 2019 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-32118468

RESUMO

Stem cells are undifferentiated elements capable to acquire a specific cellular phenotype under the influence of specific stimuli, thus being involved in tissue integrity and maintenance. In the skin tissue self-renewal and wound healing after injury is a complex process, especially in adulthood, due to the aging process and the continuous exposure to damaging agents. The importance of stem cells in regenerative medicine is well known and defining or improving their isolation methods is therefore a primary and crucial step. In the present paper we present a novel method to isolate stem cells from human skin, including the involvement of a novel medium for the maintenance and expansion of in vitro cultures. The biopsies were mechanically digested and put in culture. The migrating cells were positive selected with magnetic cell sorting, characterized by flow-cytometry analysis, and viability detected by MTT assay. Cells exhibited a mesenchymal phenotype, as demonstrated by the positive acquirement of an osteogenic or adipogenic phenotype when cultured in specific conditioned media. Taken together our results disclose a novel method for culturing and expanding stem cells from skin and pave the way for future clinical applications in tissue regeneration.


Assuntos
Separação Celular/métodos , Pele/citologia , Células-Tronco , Humanos
6.
Calcif Tissue Int ; 102(3): 373-379, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29101475

RESUMO

Osteogenesis imperfecta or "brittle bone disease" is a congenital disorder of connective tissue causing the bone to break easily. Around 85-90% of cases are due to autosomal dominant mutations in the genes encoding type I collagen, the major organic component of bone. Genotype-phenotype correlations have shown that quantitative defects of collagen type I lead to mild OI, whereas structural defects show a wide clinical range from mild to perinatal lethal. This may partially be explained by the type of amino acid substitution and the relative location in the domain structure. To fully understand the variability of the clinical manifestation and the underlying pathomechanisms, further investigations are required. Here we provide the first biochemical characterization of a mutation at the signal peptide cleavage site of COL1A1, a domain not yet characterized. By steady-state analysis, we observed reduced production of collagen type I. Furthermore, by pulse-chase analysis we detected delayed secretion and partial intracellular retention of collagen I. In the cellular fraction, the electrophoretic migration was abnormal; however, secreted type I collagen showed a normal migration pattern. The intracellular retention of collagen I was confirmed by immunofluorescent staining. Moreover, transmission electron microscopy of cultured fibroblasts revealed enlargement of ER cisternae. These results further support the hypothesis that mechanisms interfering with ER integrity play an important role in the pathology of severe OI.


Assuntos
Colágeno Tipo I/genética , Heterozigoto , Mutação/genética , Osteogênese Imperfeita/genética , Sinais Direcionadores de Proteínas/genética , Osso e Ossos/metabolismo , Colágeno/metabolismo , Colágeno Tipo I/metabolismo , Cadeia alfa 1 do Colágeno Tipo I , Fibroblastos/patologia , Genótipo , Humanos , Fenótipo
7.
Braz J Med Biol Res ; 50(8): e6512, 2017 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-28746470

RESUMO

Sickle cell anemia (SCA) causes dysfunction of multiple organs, with pulmonary involvement as a major cause of mortality. Recently, there has been growing interest in the nitrogen single-breath washout (N2SBW) test, which is able to detect ventilation heterogeneity and small airway disease when the results of other pulmonary function tests (PFTs) are still normal. Thus, the objectives of the present study were to assess the heterogeneity in the ventilation distribution in adults with SCA and to determine the association between the ventilation distribution and the clinical, cardiovascular, and radiological findings. This cross-sectional study included 38 adults with SCA who underwent PFTs, echocardiography, computed tomography (CT), and 6-min walk test. To evaluate the ventilation heterogeneity, the patients were categorized according to the phase III slope of the N2SBW (SIIIN2). Compared with adults with lower SIIIN2 values, adults with higher SIIIN2 values showed lower hemoglobin levels (P=0.048), a history of acute chest syndrome (P=0.001), an elevated tricuspid regurgitation velocity (P=0.039), predominance of a reticular pattern in the CT (P=0.002), a shorter 6-min walking distance (6MWD) (P=0.002), and lower peripheral oxygen saturation (SpO2) after exercise (P=0.03). SIIIN2 values correlated significantly with hemoglobin (rs=-0.344; P=0.034), forced vital capacity (rs=-0.671; P<0.0001), diffusing capacity for carbon monoxide (rs=-0.376; P=0.019), 6MWD (rs=-0.554; P=0.0003), and SpO2 after exercise (P=0.040). Heterogeneity in the ventilation distribution is one of the most common pulmonary dysfunctions in adults with SCA. Moreover, relationships exist between ventilation heterogeneity, worsening of pulmonary structural damage, and reduced tolerance for exercise.


Assuntos
Anemia Falciforme/fisiopatologia , Tolerância ao Exercício/fisiologia , Pulmão/fisiopatologia , Adulto , Testes Respiratórios , Estudos Transversais , Ecocardiografia , Feminino , Humanos , Masculino , Nitrogênio , Testes de Função Respiratória , Tomografia Computadorizada por Raios X , Teste de Caminhada , Adulto Jovem
8.
Eur Rev Med Pharmacol Sci ; 20(19): 4041-4047, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27775795

RESUMO

OBJECTIVE: H. pylori infection is reportedly associated with autoimmune diseases such as chronic thyroiditis and autoimmune diabetes. The aim of this study is to determine the association between H. pylori infection and its virulent strain CagA with antibodies against thyroperoxidase (TPO Ab) and thyrotropin (TSH) in a cohort of latent autoimmune diabetes in adult (LADA) patients. PATIENTS AND METHODS: We included 234 LADA patients (53.8% women). Antibodies against H. pylori whole antigens and CagA, TPO Ab and TSH were assessed in all patients. RESULTS: Prevalence of IgG against H. pylori and GagA was 52.1% and 20.9% respectively. Antibodies against H. pylori were not associated with TPO Ab and TSH (rho = 0.067, p = 0.620 and rho = 0.156, p = 0.099, respectively). Antibodies against CagA showed a positive association with TSH and TPO Ab (respectively rho = 0.309, p = 0.036 and rho = 0.419, p = 0.037). Subjects with hypothyroidism (TSH ≥ 3.5 µU/ml) had an increased frequency of Ab anti CagA (p = 0.059). CONCLUSIONS: The infection by H. pylori strains expressing CagA is associated with increased TPO Ab and TSH levels in LADA patients, suggesting a possible mechanism involved in thyroid autoimmunity and dysfunction of the gland. Further research is needed to test this hypothesis.


Assuntos
Infecções por Helicobacter/complicações , Helicobacter pylori/imunologia , Diabetes Autoimune Latente em Adultos , Tireoidite , Adulto , Anticorpos Antibacterianos , Antígenos de Bactérias , Proteínas de Bactérias , Diabetes Mellitus Tipo 1 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
Aust Dent J ; 60(3): 276-93, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25790344

RESUMO

BACKGROUND: Carious affected dentine (CAD) represents a very common substrate in adhesive dentistry. Despite its ability to interact with adhesive systems, the intrinsic character of CAD leads to lower bonding compared with sound dentine, regardless of the adhesive systems used. This low bonding may be more susceptible to leakage and hydrolysis of the interface by matrix metalloproteinases (MMPs). This systematic review aimed to determine current knowledge of CAD bonding, together with bond strength and MMP inhibitors' ability to prevent hybrid layer instability. METHODS: MEDLINE/Pubmed, Scopus and The Cochrane Library databases were electronically searched for articles published from 1 January 1960 to 31 August 2014. Two reviewers independently screened and included papers according to predefined selection criteria. RESULTS: The electronic searches identified 320 studies. After title, abstract and full-text examinations, 139 articles met the inclusion criteria. Data highlighted that a poor resin saturation of the already demineralized collagen matrix in CAD is strictly related to nanoleakage in interdiffusion and is the basis of the progressive decrease in strength with hydrolysis by MMPs. The use of mild self-etching systems seems to be the more accredited method to establish bonding in CAD. Inhibitors of MMPs may ensure better performance of CAD bonding, allowing undisturbed remineralization of the affected matrix. CONCLUSIONS: CAD bonding needs further understanding and improvement, particularly to enhance the strength and durability of the hybrid layer.


Assuntos
Colagem Dentária , Cárie Dentária/patologia , Cimentos Dentários/química , Dentina/patologia , Infiltração Dentária/prevenção & controle , Dentina/efeitos dos fármacos , Humanos , Inibidores de Metaloproteinases de Matriz/farmacologia , Estresse Mecânico
10.
Rev. bras. plantas med ; 17(1): 9-17, Jan-Mar/2015. graf
Artigo em Português | LILACS | ID: lil-742924

RESUMO

Plectranthus barbatus Andrews (Lamiaceae) é uma planta muita utilizada na medicina popular para o tratamento de doenças gastrointestinais e hepáticas. O objetivo do presente trabalho foi estudar o efeito protetor do extrato aquoso de P. barbatus (EAPB) sobre os danos hepáticos causados pela sobrecarga de ferro provocada pelo ferro-dextran em ratos. O tratamento com ferro-dextran induziu uma redução significativa na concentração de glutationa reduzida nos animais tratados em relação ao grupo controle e o tratamento prévio dos animais com o EAPB protegeu o fígado do efeito provocado pelo ferro neste parâmetro. Com relação à lipoperoxidação, houve aumento significativo na concentração de malondialdeído (MDA) nos animais tratados em relação ao controle, entretanto, quando os animais receberam o tratamento prévio com o EAPB, houve redução significativa na concentração do MDA. A análise histopatológica mostrou que o grupo tratado com ferro-dextran apresentou grânulos de ferro no citoplasma das células de Kupffer com alargamento das mesmas e algumas com os núcleos hipertróficos. O tratamento prévio com EAPB resultou no desaparecimento dos sinais de danos às células de Kupffer sem nenhum núcleo hipertrófico, mas com a presença de grânulos de ferro totalmente fagocitados, o que demonstra uma aparência morfológica normal. Portanto, o EAPB pode ser útil na prevenção de danos hepáticos induzidos por sobrecarga de ferro.


The Plectranthus barbatus Andrews (Lamiaceae) is a plant largely used in folk medicine to treat gastrointestinal and liver diseases. The objective of this work was to study the protective effect of the aqueous extract of P. barbatus (EAPB) against damage caused by iron overload induced by iron dextran in rat liver. Treatment with iron-dextran induced a significant reduction in the glutathione levels in treated animals compared to control group, and the pretreatment of animals with EAPB protected the liver from the effects caused by iron in this parameter. With respect to lipid peroxidation, a significant increase in the malondialdehyde (MDA) levels in treated animals compared to control was observed; however, when the animals were pretreated with EAPB, there was a significant reduction in the MDA levels. Histopathological analysis showed that the group treated with iron-dextran showed iron granules in the cytoplasm of the Kupffer cells and some of them presented enlarged nuclei. The group previously treated with EAPB showed the disappearance of the signs of damage to the Kupffer cells with no nucleus hypertrophy but with the presence of iron granules completely phagocytosed by these cells, which showed a normal morphological appearance. Therefore, the EAPB may be useful in the prevention of liver damage induced by iron overload.


Assuntos
Animais , Masculino , Ratos , Estresse Oxidativo/fisiologia , Plectranthus/efeitos adversos , Toxicidade , Gastroenteropatias/classificação , Ferro/agonistas , Fígado/fisiopatologia
11.
Sci Rep ; 4: 6373, 2014 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-25224681

RESUMO

Decline in the gene expression of senescence repressor Bmi1, and telomerase, together with telomere shortening, underlay senescence of stem cells cultured for multiple passages. Here, we investigated whether the impairment of senescence preventing mechanisms can be efficiently counteracted by exposure of human adipose-derived stem cells to radio electric asymmetrically conveyed fields by an innovative technology, named Radio Electric Asymmetric Conveyer (REAC). Due to REAC exposure, the number of stem cells positively stained for senescence associated ß-galactosidase was significantly reduced along multiple culturing passages. After a 90-day culture, REAC-treated cells exhibited significantly higher transcription of Bmi1 and enhanced expression of other stem cell pluripotency genes and related proteins, compared to unexposed cells. Transcription of the catalytic telomerase subunit (TERT) was also increased in REAC-treated cells at all passages. Moreover, while telomere shortening occurred at early passages in both REAC-treated and untreated cells, a significant rescue of telomere length could be observed at late passages only in REAC-exposed cells. Thus, REAC-asymmetrically conveyed radio electric fields acted on a gene and protein expression program of both telomerase-independent and telomerase-dependent patterning to optimize stem cell ability to cope with senescence progression.


Assuntos
Tecido Adiposo/citologia , Diferenciação Celular/efeitos da radiação , Senescência Celular/efeitos da radiação , Estimulação Elétrica , Ondas de Rádio , Células-Tronco/citologia , Telomerase/metabolismo , Tecido Adiposo/metabolismo , Tecido Adiposo/efeitos da radiação , Western Blotting , Proliferação de Células , Células Cultivadas , Senescência Celular/fisiologia , Humanos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células-Tronco/metabolismo , Células-Tronco/efeitos da radiação , Telomerase/genética , Telômero/genética , beta-Galactosidase/metabolismo
12.
Neth J Med ; 71(1): 17-21, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23412818

RESUMO

Megestrol acetate (MA) is a progestational agent for the treatment of metastatic breast cancer and endometrial cancer. MA has also been used to promote weight gain in malnourished elderly patients, in patients with immunodeficiency virus and in cancer-induced cachexia. In addition to thromboembolic disease, MA may induce hyperglycaemia, osteoporosis, suppression of the gonadal axis, and Cushing's syndrome. MA has also been shown to cause symptomatic suppression of the hypothalamic-pituitary-adrenal (HPA) axis owing to its intrinsic glucocorticoid-like effect. Three additional patients are presented who developed symptomatic adrenal insufficiency while they were receiving 160-320 mg MA daily. The patients were treated with cortisone acetate supplements, had clear evidence of HPA-axis suppression but recovered fully after MA was discontinued. Patients receiving MA might have an inadequate adrenal response during stressful conditions, possibly because 160-320 mg MA daily may not provide adequate protection to prevent the symptoms of adrenal insufficiency. The adverse MA effect on the HPA axis is probably not well recognised in clinical practice, and clinicians need an increased awareness of the endocrine complications secondary to MA treatment.


Assuntos
Doença de Addison/induzido quimicamente , Antineoplásicos Hormonais/efeitos adversos , Acetato de Megestrol/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino
13.
Nutr Metab Cardiovasc Dis ; 23(3): 212-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21958760

RESUMO

BACKGROUND AND AIMS: A demographic analysis in the Mediterranean island of Sardinia revealed marked differences in extreme longevity across the 377 municipalities and particularly identified a mountain inner area where the proportion of oldest subjects among male population has one of the highest validated value worldwide. The cause(s) of this unequal distribution of male longevity may be attributed to a concurrence of environmental, lifestyle and genetic factors. METHODS AND RESULTS: In this study we focussed on some lifestyle and nutrition variables recorded in the island's population in early decades of 20th century, when agricultural and pastoral economy was still prevalent, and try to verify through ecological spatial models if they may account for the variability in male longevity. By computing the Extreme Longevity Index (the proportion of newborns in a given municipality who reach age 100) the island's territory was divided in two areas with relatively higher and lower level of population longevity. Most nutritional variables do not show any significant difference between these two areas whereas a significant difference was found with respect to pastoralism (P = 0.0001), physical activity estimated by the average slope of the territory in each municipality (P = 0.0001), and average daily distance required by the active population to reach the usual workplace (P = 0.0001). CONCLUSION: Overall, these findings suggest that factors affecting the average energy expenditure of male population such as occupational activity and geographic characteristics of the area where the population mainly resides, are important in explaining the spatial variation of Sardinian extreme longevity.


Assuntos
Estilo de Vida , Longevidade , Estado Nutricional , Demografia , Meio Ambiente , Humanos , Itália/epidemiologia , Modelos Logísticos , Masculino , Atividade Motora , Ocupações , Prevalência , Fatores de Risco , Fatores Socioeconômicos
14.
J Thromb Haemost ; 9(12): 2361-70, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21929513

RESUMO

BACKGROUND: Even although time to treatment has been shown to be a determinant of mortality in primary angioplasty, the potential benefits are still unclear from early pharmacological reperfusion by glycoprotein (Gp) IIb-IIIa inhibitors. Therefore, the aim of this meta-analysis was to combine individual data from all randomized trials conducted on upstream as compared with late peri-procedural abciximab administration in primary angioplasty. METHODS: The literature was scanned using formal searches of electronic databases (MEDLINE and EMBASE) from January 1990 to December 2010. All randomized trials on upstream abciximab administration in primary angioplasty were examined. No language restrictions were enforced. RESULTS: We included a total of seven randomized trials enrolling 722 patients, who were randomized to early (n = 357, 49.4%) or late (n = 365, 50.6%) peri-procedural abciximab administration. No difference in baseline characteristics was observed between the two groups. Follow-up data were collected at a median (25th-75th percentiles) of 1095 days (720-1967). Early abciximab was associated with a significant reduction in mortality (primary endpoint) [20% vs. 24.6%; hazard ratio (HR) 95% confidence interval (CI) = 0.65 (0.42-0.98) P = 0.02, P(het) = 0.6]. Furthermore, early abciximab administration was associated with a significant improvement in pre-procedural thrombolysis in myocardial infarction (TIMI) 3 flow (21.6% vs. 10.1%, P < 0.0001), post-procedural TIMI 3 flow (90% vs. 84.8%, P = 0.04), an improvement in myocardial perfusion as evaluated by post-procedural myocardial blush grade (MBG) 3 (52.0% vs. 43.2%, P = 0.03) and ST-segment resolution (58.4% vs. 43.5%, P < 0.0001) and significantly less distal embolization (10.1% vs. 16.2%, P = 0.02). No difference was observed in terms of major bleeding complications between early and late abciximab administration (3.3% vs. 2.3%, P = 0.4). CONCLUSIONS: This meta-analysis shows that early upstream administration of abciximab in patients undergoing primary angioplasty for ST-segment elevation myocardial infarction (STEMI) is associated with significant benefits in terms of pre-procedural epicardial re-canalization and ST-segment resolution, which translates in to significant mortality benefits at long-term follow-up.


Assuntos
Angioplastia , Anticorpos Monoclonais/uso terapêutico , Fragmentos Fab das Imunoglobulinas/uso terapêutico , Integrina beta3/efeitos dos fármacos , Inibidores da Agregação Plaquetária/uso terapêutico , Abciximab , Anticorpos Monoclonais/farmacologia , Humanos , Fragmentos Fab das Imunoglobulinas/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
Neuroscience ; 194: 136-49, 2011 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-21824508

RESUMO

The cortical representation of heading perception derives from several functional processes distributed across many cortical areas. The aim of the present study was to assess if the optic flow motion directions, expansion and contraction, differently modulate the firing activity of area PEc neurons. We determined the influence of the eye position and/or the spatial position of the focus of expansion (FOE) on this activity. Single neuron activity during radial optic flow stimulation was recorded in three behaving monkeys. The retinal FOE position and the spatial eye position were examined in order to study eye position's influence upon the directional selectivity for the radial stimuli. We observed that the neurons able to discriminate the retinotopic FOE position are differently modulated by expansion and contraction. One class of neurons exhibited a different preferred FOE position during expansion and contraction. A second class showed the same preferred position with similar firing activity in the two stimuli. A third class showed the same preferred position but different firing activity. Eye position affected the directional selectivity of most PEc cells. The main result of this study is that there is a continuum in cell modulation by optic flow direction, and it can be modified by the angle of gaze with respect to the FOE. These results shed light on potential cellular integrative mechanisms of area PEc in heading perception.


Assuntos
Percepção de Movimento/fisiologia , Fluxo Óptico/fisiologia , Lobo Parietal/fisiologia , Células Receptoras Sensoriais/fisiologia , Percepção Espacial/fisiologia , Potenciais de Ação/fisiologia , Animais , Comportamento Animal/fisiologia , Movimentos Oculares/fisiologia , Macaca fascicularis , Masculino , Lobo Parietal/anatomia & histologia , Córtex Visual/anatomia & histologia , Córtex Visual/fisiologia , Vias Visuais/anatomia & histologia , Vias Visuais/fisiologia
16.
Neuroscience ; 171(4): 1241-55, 2010 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-20870015

RESUMO

The visual perception of self-motion is mainly provided by optic flow. Eyes usually scan the environment during locomotion, and the gaze is not always directed to the focus of expansion (FOE) of the flow field. Such eye movements change the retinal FOE position with respect to the fovea. Here, we assess if optic flow selective neurons in parietal area PEc are modulated by eye position. We recorded single neuron activity during radial optic flow stimulation in two monkeys, varying eye and retinal FOE positions. We found that the majority of PEc neurons are modulated by the FOE retinotopic position with different tuning for expansion and contraction. Although many neurons did not show any gaze field without visual stimulation, the eye position modulated optic flow responses in about half of the cells. These novel results suggest that PEc neurons integrate both visual and eye position signals, and allow us to hypothesize their role in guiding locomotion as a part of a cortical network involved in FOE representation during self-motion. Visual and eye position interaction in this area could be seen as a contribution to the building of the invariant space representation necessary to motor planning.


Assuntos
Fluxo Óptico/fisiologia , Células Receptoras Sensoriais/fisiologia , Córtex Visual/fisiologia , Vias Visuais/fisiologia , Análise de Variância , Animais , Movimentos Oculares/fisiologia , Lateralidade Funcional , Macaca fascicularis , Masculino , Estimulação Luminosa/métodos , Psicofísica , Tempo de Reação , Córtex Visual/citologia , Campos Visuais/fisiologia
17.
Eur J Endocrinol ; 163(4): 541-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20603341

RESUMO

OBJECTIVE: In latent autoimmune diabetes of adults (LADA), the progression into insulin-dependent diabetes is usually faster than in type 2 diabetes (T2D) but the factors influencing this progression are not completely known. In this study, we searched for sensitive markers associated with early development of insulin dependence. DESIGN: The screening of 5568 T2D patients for glutamic acid decarboxylase autoantibodies (GAD65Ab) identified 276 LADA patients (M=131; F=145) and in 251 of them, tyrosine phosphatase-2 (IA-2Ab) and thyroperoxidase autoantibodies (TPOAbs), some clinical features and genotype variation of the main type 1 diabetes (T1D) disease susceptibility loci (HLA-DRB1 and HLA-DQB1) were analyzed. RESULTS: Four years after the diagnosis of diabetes, high GAD65Ab titer was not significantly associated with faster progression toward insulin deficiency (P=0.104). Patients with GAD65Ab and TPOAb or IA-2Ab or triple positivity for both islet and TPOAbs (GAD65Ab/IA-2Ab/TPOAb) showed a significantly faster disease progression (P=0.002). Among 104 TPOAb-positive LADA patients, 10 received replacement therapy (l-thyroxine), 43 showed high TSH levels (62.7% developed insulin dependence), and 3 had hyperthyroidism treated with methimazole. Multivariate analysis revealed a significant effect on disease progression only for TPOAb (P=0.022), female gender (P=0.036), low body mass index (BMI; P=0.001), and T1D high/intermediate risk HLA-DRB1/DQB1 genotypes grouped (P=0.020). CONCLUSIONS: High GAD65Ab titers per se are not a major risk factor for disease progression in LADA, while the number of positive autoantibodies and HLA DRB1-DQB1 genotypes at high risk for T1D are significant predictors. Moreover, clinical characteristics such as low BMI and female gender are more likely to identify patients who will require insulin therapy within 4 years of diagnosis.


Assuntos
Autoanticorpos/imunologia , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Glutamato Descarboxilase/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Insulina/uso terapêutico , Adulto , Idoso , Diabetes Mellitus Tipo 1/tratamento farmacológico , Feminino , Predisposição Genética para Doença/genética , Genótipo , Antígenos HLA-DQ/genética , Cadeias alfa de HLA-DQ , Cadeias beta de HLA-DQ , Antígenos HLA-DR/genética , Cadeias HLA-DRB1 , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade
18.
Clin Ter ; 160(3): 217-21, 2009.
Artigo em Italiano | MEDLINE | ID: mdl-19756325

RESUMO

A case report of a non-diabetic alcoholic patient (ethanol intake >220 g/d) who experienced severe hypertriglyceridemia (12.679 mg/dL) without pancreatitis or detectable genetic factors responsible for severe dyslipidemia is described. Following the normalization of triglyceride and cholesterol levels, through lipid-free parenteral nutrition therapy, a regimen of alcohol withdrawal and a well-balanced diet with less than 10% saturated fat maintained a normal lipid profile without requiring any lipid-lowering drug. The absence of organ damage in the patient is likely to be attributed to the short duration of the elevated triglyceride peak. The treatment of this disorder does not necessarily require LDL-apheresis but can be simply managed by parenteral therapy provided that no other risk factors are present.


Assuntos
Alcoolismo/complicações , Hipertrigliceridemia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença
19.
Neuroscience ; 156(3): 413-24, 2008 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-18782605

RESUMO

Neurons in area PEc in the superior parietal cortex encode signals from different modalities, such as visual, extraretinal and somatosensory, probably combining them to encode spatial parameter of extrapersonal space to prepare body movements. This study reports the characterization of the functional properties of PEc non-visual neurons that showed saccade-related activity. We analyzed the pre- and post-saccadic firing activity in 189 neurons recorded in five hemispheres of three behaving monkeys. Spiking activity of PEc single neurons was recorded while the monkeys performed visually-guided saccades in a reaction time task. We found that 84% of neurons recorded from area PEc showed pre-saccadic activity with directional tuning. In 26% of neurons, we found inhibition of activity in the pre-saccadic period. The onset of this "pause" always started before the saccade and, in 51% of neurons, it was invariant among different gaze directions. The post-saccadic activity in these cells was either a phasic response with directional tuning (77%) and/or an eye position tuning (75%). The analysis of the preferred direction did not show hemispheric preference, however, for the majority of neurons, the angular difference in the preferred direction, in the pre- and post-saccadic period, was more than 60 degrees . By confirming, therefore, that PEc neurons carry information about eye position, these novel findings open new horizons on PEc function that, to date, is not well documented. The pre-saccadic activity may reflect an involvement in saccade control, whereas post-saccadic activity may indicate a role in informing on the new eye position. These novel results about saccade and eye position processing may imply a role of area PEc in gaze direction mechanisms and, possibly, in remapping visual space after eye movements.


Assuntos
Potenciais de Ação/fisiologia , Fixação Ocular/fisiologia , Neurônios/fisiologia , Lobo Parietal/citologia , Movimentos Sacádicos/fisiologia , Animais , Comportamento Animal , Distribuição de Qui-Quadrado , Lateralidade Funcional/fisiologia , Macaca fascicularis , Masculino , Inibição Neural/fisiologia , Orientação/fisiologia , Tempo de Reação/fisiologia , Campos Visuais/fisiologia , Percepção Visual/fisiologia
20.
Heart ; 94(12): 1548-58, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18474534

RESUMO

BACKGROUND: Even though time-to-treatment has been shown to be a determinant of mortality in primary angioplasty, the potential benefits from early pharmacological reperfusion by glycoprotein (Gp) IIb-IIIa inhibitors are still unclear. The aim of this meta-analysis was to combine individual data from all randomised trials conducted on facilitated primary angioplasty by the use of early Gp IIb-IIIa inhibitors. METHODS AND RESULTS: The literature was scanned by formal searches of electronic databases (MEDLINE, EMBASE) from January 1990 to October 2007. All randomised trials on facilitation by the early administration of Gp IIb-IIIa inhibitors in ST-segment elevation myocardial infarction (STEMI) were examined. No language restrictions were enforced. Individual patient data were obtained from 11 out of 13 trials, including 1662 patients (840 patients (50.5%) randomly assigned to early and 822 patients (49.5%) to late Gp IIb-IIIa inhibitor administration). Preprocedural Thrombolysis in Myocardial Infarction Study (TIMI) grade 3 flow was more frequent with early Gp IIb-IIIa inhibitors. Postprocedural TIMI 3 flow and myocardial blush grade 3 were higher with early Gp IIb-IIIa inhibitors but did not reach statistical significance except for abciximab, whereas the rate of complete ST-segment resolution was significantly higher with early Gp IIb-IIIa inhibitors. Mortality was not significantly different between groups, although early abciximab demonstrated improved survival compared with late administration, even after adjustment for clinical and angiographic confounding factors. CONCLUSIONS: This meta-analysis shows that pharmacological facilitation with the early administration of Gp IIb-IIIa inhibitors in patients undergoing primary angioplasty for STEMI is associated with significant benefits in terms of preprocedural epicardial recanalisation and ST-segment resolution, which translated into non-significant mortality benefits except for abciximab.


Assuntos
Angioplastia Coronária com Balão/métodos , Infarto do Miocárdio/cirurgia , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Idoso , Angiografia Coronária , Circulação Coronária/fisiologia , Creatina Quinase/metabolismo , Embolia/prevenção & controle , Tratamento de Emergência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/enzimologia , Infarto do Miocárdio/mortalidade , Revascularização Miocárdica/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...