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2.
Clin Microbiol Infect ; 24(2): 118-124, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28887186

RESUMO

BACKGROUND: Lyme borreliosis (LB) is a tick-borne infection caused by Borrelia burgdorferi sensu lato. The most frequent clinical manifestations are erythema migrans and Lyme neuroborreliosis. Currently, a large volume of diagnostic testing for LB is reported, whereas the incidence of clinically relevant disease manifestations is low. This indicates overuse of diagnostic testing for LB with implications for patient care and cost-effective health management. AIM: The recommendations provided in this review are intended to support both the clinical diagnosis and initiatives for a more rational use of laboratory testing in patients with clinically suspected LB. SOURCES: This is a narrative review combining various aspects of the clinical and laboratory diagnosis with an educational purpose. The literature search was based on existing systematic reviews, national and international guidelines and supplemented with specific citations. IMPLICATIONS: The main recommendations according to current European case definitions for LB are as follows. Typical erythema migrans should be diagnosed clinically and does not require laboratory testing. The diagnosis of Lyme neuroborreliosis requires laboratory investigation of the spinal fluid including intrathecal antibody production, and the remaining disease manifestations require testing for serum antibodies to B. burgdorferi. Testing individuals with non-specific subjective symptoms is not recommended, because of a low positive predictive value.


Assuntos
Técnicas de Laboratório Clínico , Doença de Lyme/diagnóstico , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Borrelia burgdorferi/imunologia , Técnicas de Laboratório Clínico/normas , Humanos , Imunoglobulina M/sangue , Imunoglobulina M/imunologia
4.
Clin Microbiol Infect ; 21(12): 1098-103, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26321669

RESUMO

The aim of this study was to determine whether patients with antibodies against Borrelia burgdorferi sensu lato or who report a history of erythema migrans (EM) or tick bite are more likely to have non-specific symptoms such as musculoskeletal pain, fatigue, sensory disorder, and headache. The study group comprised 423 subjects with non-specific symptoms tested for antibodies against B. burgdorferi sensu lato between July 2012 and December 2014 because of suspicion of Lyme borreliosis (LB). Of these, 285 were females (67%) and 138 were males (33%); the median age was 53 years (range, 7-89 years). Patients with a confirmed diagnosis of LB and patients with a known underlying disease that could influence the development of the symptoms were excluded from the evaluation. Subjects were assigned to the seronegative group or to one of three seropositive groups, and the history of EM and tick bite was also recorded. Statistical analysis was performed with single chi-square tests of independence and multiple logistic regression models. No differences in the occurrence of non-specific symptoms were observed between patients grouped according to antibody status. A history of EM showed no significant effect on any of the non-specific symptoms. A history of tick bite was weakly correlated with joint pain and joint swelling (p <0.05). In conclusion, it is highly unlikely that the complaints are related to a previous infection with B. burgdorferi sensu lato. The results show that testing patients with non-specific symptoms for antibodies against B. burgdorferi sensu lato in the everyday clinical setting does not provide any useful information about their aetiology.


Assuntos
Anticorpos Antibacterianos/metabolismo , Borrelia burgdorferi/imunologia , Fadiga/imunologia , Cefaleia/imunologia , Dor Musculoesquelética/imunologia , Transtornos de Sensação/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , DNA Bacteriano/análise , Eritema Migrans Crônico/imunologia , Fadiga/etiologia , Feminino , Cefaleia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Dor Musculoesquelética/etiologia , Transtornos de Sensação/etiologia , Picadas de Carrapatos/imunologia , Adulto Jovem
5.
Arzneimittelforschung ; 62(12): 655-60, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23154886

RESUMO

The aim of this study was to synthesize and determine the biological activity of new derivatives of 4-fluorobenzoic acid and tetrahydroacridine towards inhibition of cholinesterases. Compounds were synthesized in condensation reaction between 9-aminoalkyl-tetrahydroacridines and the activated 4-fluorobenzoic acid. Properties towards inhibition of acetyl- and butyrylcholinesterase were estimated according to Ellman's spectrophotometric method. Among synthesized compounds the most active were compounds 4a and 4d. These compounds, in comparison with tacrine, were characterized by the similar values of IC50. Among all obtained compounds, 4d presented the highest selectivity towards inhibition of acetylcholinesterase. Molecular modeling studies revealed that all derivatives presented similar extended conformation in the gorge of acetylcholinesterase, however, there were 2 main conformations in the active center of butyrylcholinesterase: bent and extended conformation.


Assuntos
Benzamidas/síntese química , Benzamidas/farmacologia , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/farmacologia , Acetilcolinesterase/química , Animais , Butirilcolinesterase/química , Electrophorus , Indicadores e Reagentes , Modelos Moleculares , Conformação Molecular , Espectrofotometria Ultravioleta , Relação Estrutura-Atividade
6.
Cells Tissues Organs ; 191(2): 96-104, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19641290

RESUMO

The use of implantable biomaterials, such as artificial skin substitutes used for dermal defects, remains limited by the low angiogenic potential of these products. The rapid in vivo degradation of growth factors contributes to the limiting of angiogenesis in biomaterials. Here, we report on collagen sponges in which vascular endothelial growth factor (VEGF) was immobilized through physical binding to heparin, covalently incorporated in the matrix via cross-linking with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and N-hydroxysuccinimide. The in vitro release of VEGF over time and endothelial cell proliferation were investigated in matrices modified at varying heparin to EDC ratios either nonloaded or loaded with VEGF. ELISA demonstrated a significantly slower in vitro release of VEGF over a period of 5 days from heparinized matrices as compared to their unmodified and cross-linked counterparts. The effects of these modifications on the proliferation of endothelial cells and endothelial progenitor cells were evaluated after 1, 3 and 5 days either according to the bromodeoxyuridine assay or total cell counting with a Neubauer chamber. The endothelial and endothelial progenitor cells cultured in contact with heparinized matrices loaded with VEGF revealed both the highest rate of DNA synthesis and the highest total cell count. Furthermore, these results show that the cross-linking of collagen matrices - both in the presence and absence of heparin - leads to increases of the proliferative activities. We can assume that these changes lead to matrices with increased angiogenic capabilities.


Assuntos
Materiais Biocompatíveis/farmacologia , Colágeno/farmacologia , Células Endoteliais/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/farmacologia , Proliferação de Células/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Etildimetilaminopropil Carbodi-Imida/farmacologia , Heparina/farmacologia , Humanos , Succinimidas , Engenharia Tecidual/métodos
8.
J Plast Reconstr Aesthet Surg ; 59(10): 1063-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16996429

RESUMO

Aesthetically pleasing nipple-areola reconstruction is a satisfying part of a two-stage breast reconstruction. The up to 50% [Banducci DR, Le TK, Hughes KC. Long-term follow-up of a modified Anton-Hartrampf nipple reconstruction. Ann Plast Surg 1999;43(5):467-9; discussion 469-70] postoperative shrinkage following a conventional nipple reconstruction is a well-known problem. Augmentation of the nipple with autologous banked cartilage seems to be a promising solution. From 2000-2003, 17 patients underwent a nipple-areola-complex reconstruction following secondary breast reconstruction using free perforator flaps. The rib cartilage harvested during the preparation of the internal thoracic vessels was banked subcutaneously and six months later replanted under the 'arrow flap' after contouring it in a 'mushroom' shape. One year later the shrinkage of the nipple in comparison to the intraoperative status was measured. In addition, patients were asked about their personal palpation impression and the aesthetic outcome. The average height decreased one year postoperatively about 25%. Thirteen of 17 patients judged the aesthetic outcome as very good, 16 nipples healed without cartilage protrusion and no patient felt discomfortable stiffness of the nipple. Our concept of a nipple augmentation with rib cartilage improves the projection and allows a more correct judgement of the later nipple shrinkage. We consider this technique to be an aesthetically satisfying and safe method, which could be used with any kind of breast reconstruction.


Assuntos
Cartilagem/transplante , Mamoplastia/métodos , Mamilos/cirurgia , Retalhos Cirúrgicos , Estética , Feminino , Seguimentos , Humanos , Mastectomia , Mamilos/patologia , Satisfação do Paciente , Costelas , Resultado do Tratamento
9.
J Biomater Sci Polym Ed ; 17(1-2): 61-75, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16411599

RESUMO

The sterilization of porous collagen sponges remains a challenging procedure. Gamma irradiation denatures collagen, resulting in dramatic changes to its structure. Ethylene oxide leaves toxic residues requiring weeks to evaporate. This study investigated the impact on cell behavior of gas plasma treatment when combined with vacuum freeze-drying. The goal of this procedure is to eliminate the molecules of hydrogen peroxide remaining after the sterilization process, together with their decomposition products, from the scaffolds. These molecules hinder the immediate use of the porous designs. Collagen and EDC/NHS-heparinized collagen scaffolds were sterilized with gas plasma. H2O2 released by the collagen specimens was measured by peroxidase test both immediately and also 1 week after the plasma treatment. Further measurements were done 24, 36, 48 and 72 h after vacuum freeze-drying. The activity of these scaffolds was further evaluated in relation to the proliferation, migration and differentiation of human umbilical vein endothelial cells (HUVECs). Both immediately after exposure to gas plasma and also 1 week later, the collagen designs contained significantly higher concentrations of H2O2 than scaffolds having also undergone vacuum freeze-drying. This procedure achieved faster decontamination of the remaining H2O2. Following vacuum freeze-drying, sponges already allowed HUVEC proliferation after 48 h, but in non-lyophilized specimens after gas plasma treatment alone, cell death occurred as early as only 1 week later. These data highlight the advantages of carrying out vacuum freeze-drying following gas plasma sterilization. The results show the substantial impact of sterilization of porous materials made for tissue engineering.


Assuntos
Colágeno/química , Esterilização , Animais , Bovinos , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Colágeno/toxicidade , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Liofilização , Humanos , Peróxido de Hidrogênio , Porosidade , Cordão Umbilical/citologia , Cordão Umbilical/efeitos dos fármacos , Vácuo
10.
Int J Artif Organs ; 29(12): 1167-73, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17219357

RESUMO

Ongoing research has achieved much progress towards the development of new artificial skin substitute products. However, effective implant material for correcting full-thickness defects (such as those arising from extensive burns, tumor resection, hereditary or congenital defects and chronic wounds) has not yet become available. Following split-thickness skin grafting, contraction and scar formation are unavoidable. These phenomena are believed to be due to poor dermis regeneration. Collagen dermis substitute has been developed for the treatment of deep, poorly vascularized tissue defects. However, their application is problematic, because scaffolds of this kind fail to adequately induce the neoangiogenesis needed for regeneration. To overcome these shortcomings a number of matrices have been chemically modified. Furthermore, these matrices first require implantation and follow-up by skin grafting 3 to 5 weeks later. In this article we describe new materials made of modified collagen which enhance dermal regeneration and neoangiogenesis. The procedure was applied in successfully dealing with full-thickness defects in pigs, with subsequent split-thickness skin grafting being performed immediately afterwards. Histological findings revealed that the neodermis obtained resembles a normal dermis structure. These scaffolds have the potential of serving as an off-the-shelf skin replacement in the reconstruction of deep wounds, thus supporting wound-healing processes.


Assuntos
Butileno Glicóis , Colágeno , Derme/fisiologia , Etildimetilaminopropil Carbodi-Imida , Regeneração Tecidual Guiada/métodos , Cicatrização/fisiologia , Animais , Derme/lesões , Feminino , Transplante de Pele , Pele Artificial , Suínos
11.
Int J Artif Organs ; 28(12): 1251-8, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16404702

RESUMO

The most commonly used biomaterials fail to ensure sufficient angiogenesis for fast in vivo incorporation. This results in central necrosis and consequent infection. One way of obtaining a high angiogenic response is the application of vascular endothelial growth factor (VEGF). To obtain a sustained release of these cytokines, heparin was incorporated into collagen matrices using 1-ethyl-3(3-dimethyl-aminopropyl) carbodiimide (EDC) and N-hydroxysuccinmide (NHS). The functionality of the heparinized collagen matrices was then enhanced by immobilization of VEGF via its heparin-binding domain. This procedure changed in vitro degradation behavior and water-binding capacity. Accelerated endothelial cell proliferation was also achieved. A range of different heparin and EDC/NHS concentrations in combination with VEGF induced variation in endothelial cell growth and tubulogenic formation. Polymerized collagen scaffolds presented biointeractive systems with integrated angiogenic activity. This may become a useful tool in the clinical therapy of disorders connected with wound healing.


Assuntos
Colágeno Tipo I/química , Endotélio Vascular/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Engenharia Tecidual/métodos , Veias Umbilicais/citologia , Proliferação de Células , Células Cultivadas , Combinação de Medicamentos , Etildimetilaminopropil Carbodi-Imida/farmacologia , Heparina/farmacologia , Humanos , Microscopia Eletrônica , Succinimidas/farmacologia , Fator A de Crescimento do Endotélio Vascular/farmacologia
12.
Tissue Eng ; 10(9-10): 1502-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15588409

RESUMO

One of the prominent shortcomings of matrices for tissue engineering is their poor ability to support angiogenesis. We report here on experiments to enhance the angiogenic properties of collagen matrices. Our aim is to achieve this goal by covalently incorporating heparin into collagen matrices and by physically immobilizing angiogenic vascular endothelial growth factor (VEGF) to the heparin. The immobilization of heparin was performed with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) and N-hydroxysuccinimide (NHS). Carboxyl groups on the heparin are activated to succinimidyl esters, which react with amino functions on the collagen to zero length cross-links. This modification leads--in addition to the incorporation of heparin--to gross changes in in vitro degradation behavior and water-binding capacity. As a first approach to testing angiogenic capabilities, endothelial cells were exposed to nonmodified and heparinized collagen matrices. This exposure leads to an increase in endothelial cell proliferation. The increase can be further enhanced by loading the (heparinized) collagen matrices with VEGF. Evaluation of the angiogenic potential of heparinized matrices was further investigated by exposing them to the chorioallantoic membrane of chicken embryos and to the subcutaneous tissue of rats. Both approaches show that heparinized matrices have substantially increased angiogenic potential. In particular, the loading of heparinized matrices with VEGF invokes a further increase in angiogenic potential. It is apparent that the physical binding of VEGF to heparin allows for a release that is beneficial to angiogenesis. By varying the heparin and EDC/NHS concentrations during the modification process and by varying the loading with VEGF, the angiogenic potential as well as the degradation behavior can be adapted to obtain matrices that fulfill specific angiogenic requirements in the field of tissue engineering.


Assuntos
Colágeno Tipo I/química , Sistemas de Liberação de Medicamentos/métodos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/fisiologia , Heparina/administração & dosagem , Neovascularização Fisiológica/efeitos dos fármacos , Engenharia Tecidual/métodos , Fator A de Crescimento do Endotélio Vascular/administração & dosagem , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Embrião de Galinha , Membrana Corioalantoide/irrigação sanguínea , Membrana Corioalantoide/efeitos dos fármacos , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Células Endoteliais/citologia , Heparina/química , Humanos , Ligação Proteica , Ratos , Fator A de Crescimento do Endotélio Vascular/química
13.
Cancer Res ; 53(20): 4960-70, 1993 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-8104689

RESUMO

The HER-2/neu proto-oncogene (also known as c-erb B-2) is homologous with, but distinct from, the epidermal growth factor receptor. Amplification of this gene in node-positive breast cancers has been shown to correlate with both earlier relapse and shorter overall survival. In node-negative breast cancer patients, the subgroup for which accurate prognostic data could make a significant contribution to treatment decisions, the prognostic utility of HER-2/neu amplification and/or overexpression has been controversial. The purpose of this report is to address the issues surrounding this controversy and to evaluate the prognostic utility of overexpression in a carefully followed group of patients using appropriately characterized reagents and methods. In this report we present data from a study of HER-2/neu expression designed specifically to test whether or not overexpression is associated with an increased risk of recurrence in node-negative breast cancers. From a cohort of 704 women with node-negative breast cancer who experienced recurrent disease (relapsed cases) 105 were matched with 105 women with no recurrence (disease-free controls) after the equivalent follow-up period. Immunohistochemistry was used to assess HER-2/neu expression in archival tissue blocks from both relapsed cases and their matched disease-free controls. Importantly, a series of molecularly characterized breast cancer specimens were used to confirm that the antibody used was of sufficient sensitivity and specificity to identify those cancers overexpressing the HER-2/neu protein in this formalin-fixed, paraffin-embedded tissue cohort. In addition, a quantitative approach was developed to more accurately assess the amount of HER-2/neu protein identified by immunostaining tumor tissue. This was done using a purified HER-2/neu protein synthesized in a bacterial expression vector and protein lysates derived from a series of cell lines, engineered to express a defined range of HER-2/neu oncoprotein levels. By using cells with defined expression levels as calibration material, computerized image analysis of immunohistochemical staining could be used to determine the amount of oncoprotein product in these cell lines as well as in human breast cancer specimens. Quantitation of the amount of HER-2/neu protein product determined by computerized image analysis of immunohistochemical assays correlated very closely with quantitative analysis of a series of molecularly characterized breast cancer cell lines and breast cancer tissue specimens.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Receptores ErbB/biossíntese , Expressão Gênica , Proteínas Proto-Oncogênicas/biossíntese , Proto-Oncogenes , Western Blotting , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Lobular/metabolismo , Linhagem Celular , Receptores ErbB/análise , Feminino , Amplificação de Genes , Humanos , Imuno-Histoquímica , Invasividade Neoplásica , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/análise , Receptor ErbB-2 , Recidiva , Células Tumorais Cultivadas
14.
J Pharmacol Exp Ther ; 240(3): 789-94, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3559974

RESUMO

Eight acetamide analogs of oxotremorine, shown previously to be full or nearly full muscarinic agonists on the isolated guinea pig ileum, were investigated for muscarinic activity on muscle strips of guinea pig urinary bladder. Several compounds demonstrated pronounced organ selectivity when compared to carbachol by being partial agonists or antagonists on the bladder. For example, oxotremorine and BM 34, both potent, full agonists on the ileum, were partial agonists, the latter producing less than one-half the maximum response of carbachol. BM 5 elicited no significant response, but instead was a potent antagonist to carbachol. Schild analysis with BM 5 and BM 61 indicated no muscarinic receptor heterogeneity between the bladder and ileum. Also dissociation constants of agonists and partial agonists generally agreed with those determined previously on the ileum. Furthermore, the relative efficacy of each agonist appeared to be similar in the two tissues, confirming the homogeneity of muscarinic receptors in the bladder and ileum with respect to the compounds studied. Compounds having high affinity and low intrinsic efficacy, e.g., BM 5, thus may stimulate contractile responses on the ileum and block responses on the bladder and therefore display tissue selectivity without discriminating between tissue receptors. It is suggested that this selectivity is derived from a smaller effective receptor reserve for muscarinic agonists in the bladder.


Assuntos
Oxotremorina/análogos & derivados , Oxotremorina/farmacologia , Receptores Muscarínicos/fisiologia , Bexiga Urinária/fisiologia , Acetamidas/farmacologia , Animais , Carbacol/farmacologia , Cobaias , Técnicas In Vitro , Cinética , Masculino , Contração Muscular/efeitos dos fármacos , Receptores Muscarínicos/efeitos dos fármacos , Bexiga Urinária/efeitos dos fármacos
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