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1.
J Wound Care ; 29(1): 28-35, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31930941

RESUMO

OBJECTIVE: Primary lymphoedema is rare and in most cases develops in the lower extremities. In some cases, conservative treatment is insufficient and can be supported by surgical procedure. The aim of this case study was to show the difference in the effectiveness of a compression wrap device and compression stockings in the treatment of primary lymphoedema. METHOD: Before and after liposuction the patient was treated on an outpatient basis every day for three weeks. This consisted of complex decongestive therapy (CDT) including manual lymph drainage, tailored exercises, skin and nail care, compression therapy and intermittent pneumatic compression. After CDT, the patient was provided with a flat-knit compression garment. Measurements were taken at one week and at three months of wearing the compression garment. The oedema severity was measured by summary calculation method. For both healthy and swollen limbs, the sum of circumferences taken at nine fixed measuring points was determined. The difference between these sums expressed in percents was presented as a relative metric coefficient of leg lymphoedema (RMCL). RESULTS: At the start of therapy, the difference in circumference between the healthy and swollen limb was 21.85%. After CDT (RMCL: 13.46%), the patient was provided with a flat-knit compression stocking (class 3). After one week, the RMCL was 15.92%, while after three months RCML was 20.84%. Because fluid retention was observed the patient was again treated with CDT (RMCL: 13.89%). The patient was provided with compression stocking (class 4). After one week of wearing, the RMCL was 15.77%, while after three months RMCL was 20.26%. As the results proved unsatisfactory, the patient was treated with CDT (RMCL: 13.60%) and a combination of two class 4 compression stockings was used. After one week, RMCL was 14.91%, while after three months RMCL was 19.25%. As the effects of oedema reduction were insufficient, the patient was treated again with CDT (RMCL: 13.89%) and advised to replace one of the stockings with a CirAid device (adjustable compression wrap). After one week, RMCL was 14.18% and after three months RMCL was 14.76%. The patient then qualified for liposuction (RMCL: 7.81%). At three months after surgery, the compression stocking was replaced by an adjustable compression wrap, to reduce the difference in circumference between healthy and swollen limbs (from 21.85 % to 8.68%). CONCLUSION: This case study shows that in primary oedema one class of compression garment is not always sufficient, nor is the combination of two garments with varying degrees of compression. In some cases, the situation requires the use of non-elastic leg binders such as a CircAid device which, thanks to its greater stiffness, helps improve clinical outcomes.


Assuntos
Bandagens Compressivas , Lipectomia , Linfedema/terapia , Terapia por Exercício , Humanos , Dispositivos de Compressão Pneumática Intermitente , Extremidade Inferior , Linfedema/etiologia , Linfedema/cirurgia , Masculino , Massagem , Pessoa de Meia-Idade , Higiene da Pele , Meias de Compressão
2.
J Biol Chem ; 288(12): 8772-8784, 2013 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-23386612

RESUMO

The mechanisms by which Trypanosoma cruzi survives antimicrobial peptides and differentiates during its transit through the gastrointestinal tract of the reduviid vector are unknown. We show that cyclophilin, a peptidyl-prolyl isomerase secreted from T. cruzi epimastigotes, binds to and neutralizes the reduviid antimicrobial peptide trialysin promoting parasite survival. This is dependent on a singular proline residue in trialysin and is inhibited by the cyclophilin inhibitor cyclosporine A. In addition, cyclophilin-trialysin complexes enhance the production of ATP and reductase responses of parasites, which are inhibited by both calcineurin-specific inhibitors cyclosporine A and FK506. Calcineurin phosphatase activity of cyclophilin-trialysin-treated parasites was higher than in controls and was inhibited by preincubation by either inhibitor. Parasites exposed to cyclophilin-trialysin have enhanced binding and invasion of host cells leading to higher infectivity. Leishmanial cyclophilin also mediates trialysin protection and metabolic stimulation by T. cruzi, indicating that extracellular cyclophilin may be critical to adaptation in other insect-borne protozoa. This work demonstrates that cyclophilin serves as molecular sensor leading to the evasion and adaptive metabolic response to insect defense peptides.


Assuntos
Calcineurina/metabolismo , Ciclofilinas/fisiologia , Proteínas de Protozoários/fisiologia , Proteínas e Peptídeos Salivares/antagonistas & inibidores , Trypanosoma cruzi/fisiologia , Adaptação Biológica , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Ciclofilinas/metabolismo , Metabolismo Energético , Ativação Enzimática , Interações Hospedeiro-Parasita , Evasão da Resposta Imune , Leishmania/fisiologia , Mitocôndrias/metabolismo , Dados de Sequência Molecular , Oxirredutases/metabolismo , Prolina/análogos & derivados , Prolina/química , Proteínas de Protozoários/metabolismo , Ratos , Proteínas e Peptídeos Salivares/química , Proteínas e Peptídeos Salivares/fisiologia , Transdução de Sinais , Trypanosoma cruzi/enzimologia , Trypanosoma cruzi/imunologia
3.
Parasitol Res ; 113(5): 1971-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24658630

RESUMO

Antimicrobial peptides are increasingly being explored as alternative agents for therapy against the parasitic protozoan Leishmania. Previously, we reported that the synthetic magainin analog, pexiganan, induced apoptosis of surface protease-deficient Leishmania. Here, we report the development of an arginine-rich variant of this peptide which has reduced protease susceptibility and enhanced activity against wild type Leishmania in vitro. This peptide induces calcium delocalization and caspase 3/7 activity indicative of apoptosis, demonstrating that structural modification of pexiganan leads to drastic changes in biologic activity against Leishmania.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Sequência de Aminoácidos , Peptídeos Catiônicos Antimicrobianos/química , Apoptose/efeitos dos fármacos , Arginina/química , Cálcio/metabolismo , Caspases/metabolismo , Dados de Sequência Molecular , Testes de Sensibilidade Parasitária
4.
Acta Pol Pharm ; 71(1): 39-47, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24779193

RESUMO

Recently, the topic of biofilm has met a huge interest of researchers owing to a significant role played by this microbial life form in severe infections. These well organised three-dimensional microbial communities are characterized by a strong resistance to antimicrobials. Biofilms significantly contribute to morbidity and mortality as related infections are very difficult to treat due to their tendency to relapse after the withdrawal of antibiotics. According to the literature, antimicrobial peptides (AMPs) have a high potential as future antibiofilm agents. AMPs can influence various stages of biofilm formation and exhibit antimicrobial activity against a broad spectrum of microorganisms including multi-drug resistant strains. The purpose of the present study was to determine the activity of antimicrobial peptides against biofilms formed by a variety of bacterial strains. To do this, the following antimicrobial peptides were synthesized: Citropin 1.1, Lipopeptides Palm-KK-NH2 and Palm-RR-NH2, Omiganan, Pexiganan and Temporin A. Antimicrobial activity of the compounds and conventional antibiotics was determined for planktonic cells and biofilms formed by reference strains of Gram-positive (Staphylococcus aureus, S. epidermidis, Streptococcus pneumoniae, Streptococcus pyogenes) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis) bacteria. AMPs exhibited a strong antibacterial activity against Gram-positive strains, while Gram-negative bacteria were less susceptible. Antimicrobial activity of the tested peptides against biofilms formed by Gram-positive organisms was significantly stronger as compared to that of conventional antimicrobials.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Antibacterianos/farmacologia , Fenômenos Fisiológicos Bacterianos , Testes de Sensibilidade Microbiana
5.
Pharmacol Res ; 74: 7-22, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23665469

RESUMO

The incomplete inhibition of platelet function by acetylsalicylic acid (ASA), despite the patients are receiving therapeutic doses of the drug ('aspirin-resistance'), is caused by numbers of risk factors. In this study we verified the idea that plasma homocysteine (Hcy) contributes to 'aspirin-resistance' in patients with coronary artery disease (CAD) and with or without type 2 diabetes mellitus (T2DM). A cross-designed randomized controlled intervention study has been performed (126 CAD pts incl. 26 with T2DM) to determine whether increasing ASA dose from 75mg to 150mg daily may result in the increased antiplatelet effect, in the course of four-week treatment. Platelet response to collagen (coll) or arachidonic acid (AA) was monitored with whole blood aggregometry, plasma thromboxane (Tx), and Hcy levels were determined immunochemically. The ASA-mediated reductions in platelet response to coll (by 12±3%) or AA (by 10±3%) and in plasma Tx (by 20±9%; p<0.02 or less) were significantly greater for higher ASA dose and significantly correlated with plasma Hcy, which was significantly lower in "good" ASA responders compared to "poor" responders (p<0.001). Higher plasma Hcy appeared a significant risk factor for blood platelet refractoriness to low ASA dose (OR=1.11; ±95%CI: 1.02-1.20, p<0.02, adjusted to age, sex and CAD risk factors). Hcy diminished in vitro antiplatelet effect of low ASA concentration and augmented platelet aggregation (by up to 62% (p<0.005) for coll and up to 15% (p<0.005) for AA), whereas its acetyl derivative acted oppositely. Otherwise, Hcy intensified antiplatelet action of high ASA. Hyperhomocysteinaemia may be a novel risk factor for the suppressed blood platelet response to ASA, and homocysteine may act as a specific sensitizer of blood platelets to some agonists. While homocysteine per se acts as a proaggregatory agent to blood platelets, its acetylated form is able to reverse this effect. Thus, these findings reveal a possibly new challenging potential of the acetylating properties of ASA therapy.


Assuntos
Aspirina/uso terapêutico , Plaquetas/efeitos dos fármacos , Doença da Artéria Coronariana/sangue , Resistência a Medicamentos/fisiologia , Homocisteína/sangue , Inibidores da Agregação Plaquetária/uso terapêutico , Adulto , Ácido Araquidônico/farmacologia , Colágeno/farmacologia , Doença da Artéria Coronariana/tratamento farmacológico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
6.
J Pept Sci ; 18(9): 560-6, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22786744

RESUMO

LL37 and histatin 5 are antimicrobial peptides. LL37 exhibits killing activity against a broad spectrum of pathogens, whereas histatin 5 is primarily an antifungal agent. Head-to-tail cyclization of histatin 5 did not affect its antimicrobial and haemolytic activity. The cyclic LL37 exhibits identical antifungal and haemolytic activity as does LL37. Its antimicrobial activity varied in one dilution depending on the kind of bacteria. The structure of cyclic peptides was studied by circular dichroism spectroscopy. Both peptides undergo a conformational change leading to stabilisation of their α-helical structure in the presence of negatively charged sodium dodecyl sulfate micelles. However, with cyclic histatin 5, the presence of Zn(2+) ions is also necessary to fuse the peptide to the micelle. The specific action of the Zn(2+) ions is attributed to the presence of a zinc-binding motif, His-Glu-X-X-His. It has been speculated that this zinc complexing may be related to the well-established anticandidal activity. In the case of cyclic LL37, also the presence of a zwitterionic dodecylphosphocholine micelle induces formation of the helical structure. A microwave-assisted procedure for the cleavage of a peptide from the 2-chlorotrityl chloride resin was, for the first time, successfully used to obtain protected peptide fragments that can be applied to the preparation of head-to-tail cyclopeptides or to condensation of peptidic fragments.


Assuntos
Peptídeos Catiônicos Antimicrobianos/química , Histatinas/química , Peptídeos Cíclicos/síntese química , Peptídeos Cíclicos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Dicroísmo Circular , Hemólise/efeitos dos fármacos , Humanos , Micelas , Micro-Ondas , Peptídeos Cíclicos/química , Dodecilsulfato de Sódio/química , Catelicidinas
7.
Clin Interv Aging ; 15: 1533-1539, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32943856

RESUMO

The effectiveness of compression therapy in the treatment of venous leg ulcers has been confirmed in many scientific studies. The healing process depends on many of its parameters, such as the type of compression bandages, their elastic properties and sub-bandage pressure. However, there is no standard protocol that would ensure success for all patients. A pressure of about 83 mmHg provides complete compression for both superficial and deep veins; however, applying compression bandages under such high pressure is a difficult task, even for experienced therapists. Here, we present the case of a 61-year-old woman with approximately 2.5-year-old venous ulcer in her left leg due to chronic venous insufficiency (CVI). Our study aimed to show that routine pressure control at each bandage renewal using the Kikuhime device, as well as their twice daily application in the first week of therapy reduced the healing time of a venous leg ulcer with an area of about 20 cm2 to four weeks.


Assuntos
Bandagens Compressivas , Úlcera da Perna/terapia , Meias de Compressão , Úlcera Varicosa/terapia , Feminino , Humanos , Pessoa de Meia-Idade , Cicatrização
8.
J Inorg Biochem ; 107(1): 73-81, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22178668

RESUMO

The C-terminal region of Escherichia coli SlyD is unstructured and extremely rich in potential metal-binding amino acids, especially in histidine residues. SlyD is able to bind two to seven nickel ions per molecule, in a variety of coordination geometries and coordination numbers. This protein contributes to the insertion of nickel into the hydrogenase precursor protein and it has a peptidyl-prolyl cis/trans-isomerase activity which can be regulated through nickel ions. This inspired us to undertake systematic studies on the coordination ability of two histidine-rich peptides from the C-terminus of the SlyD protein with nickel. Also, it is known that histidine-rich regions are part of a Cu(2+) binding domain involved in copper uptake under conditions of metal starvation in vivo in other bacteria. For this reason we decided to examine the complex formation of Ac-AHGHVHGAHDHHHD-NH(2) and Ac-GHGHDHGHEHG-NH(2) fragments with copper ions, which are also reference metal ions in this study. Experiments were performed in a DMSO/water 30:70 solvent. The Ac-AHGHVHGAHDHHHD-NH(2) and Ac-GHGHDHGHEHG-NH(2) fragments were synthesized and their interactions with Ni(2+) and Cu(2+) ions were studied by potentiometric, mass spectrometric, UV-vis, CD, EPR, and NMR spectroscopic techniques in solution. The results show that the Ac-GHGHDHGHEHG-NH(2) fragment forms equimolar complexes with both nickel and copper ions. At physiological pH, the metal ion is bound only through nitrogens from imidazole sidechain of histidine residues. On the contrary, Ac-AHGHVHGAHDHHHD-NH(2) binds 2 metal ions per molecule, at pH range 5 to 7, even if the 1:2 metal:peptide ratios were used. NMR studies indicate the involvement of all His residues in this pH-range in metal binding of the latter peptide. At higher pH, the stoichiometry changes to 1:1 and the His residues are displaced by amide nitrogens.


Assuntos
Complexos de Coordenação/química , Cobre/química , Proteínas de Escherichia coli/química , Níquel/química , Peptídeos/química , Peptidilprolil Isomerase/química , Sequência de Aminoácidos , Sítios de Ligação , Dicroísmo Circular , Sequência Conservada , Complexos de Coordenação/síntese química , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Peptídeos/síntese química , Ligação Proteica , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Termodinâmica
9.
Future Med Chem ; 4(12): 1541-51, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22917244

RESUMO

BACKGROUND: The therapy for staphylococcal skin diseases is facing several difficulties caused by the growth of biofilms and development of resistant strains. Short synthetic lipopeptides designed on the basis of antimicrobial peptide structure seem to provide an alternative to conventional therapy. The purpose of this study was to synthesize a group of lipopeptides and evaluate their antistaphylococcal activity against biofilms formed by clinical strains of Staphylococcus aureus. RESULTS: The compounds exhibited a strong antibiofilm activity against all the isolates. The maturity of the biofilms has shown a well-defined influence on antimicrobial activity of conventional antimicrobials. DISCUSSION: Results showed that the lipopeptides were promising agents as the time of the culture did not greatly affect their activity.


Assuntos
Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Lipopeptídeos/farmacologia , Staphylococcus aureus/fisiologia , Anti-Infecciosos/uso terapêutico , Humanos , Lipopeptídeos/síntese química , Lipopeptídeos/uso terapêutico , Testes de Sensibilidade Microbiana , Percepção de Quorum/efeitos dos fármacos , Dermatopatias/tratamento farmacológico , Dermatopatias/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação
10.
Peptides ; 32(12): 2488-96, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22074954

RESUMO

An excessive production of vasoactive and proinflammatory bradykinin-related peptides, the kinins, is often involved in the human host defense against microbial infections. Recent studies have shown that a major fungal pathogen to humans, Candida albicans, can bind the proteinaceous kinin precursor, the high molecular weight kininogen (HK) and trigger the kinin-forming cascade on the cell surface. In this work, we preliminarily characterized a molecular mechanism underlying the HK adhesion to the fungal surface by (i) identification of major kininogen-binding constituents on the candidial cell wall and (ii) mapping the cell wall-binding regions on HK molecule. A major fraction of total fungal kininogen-binding capacity was assigned to ß-1,3-glucanase-extractable cell wall proteins (CWP). By adsorption of CWP on HK-coupled agarose gel and mass spectrometric analysis of the eluted material, major putative HK receptors were identified, including Als3 adhesin and three glycolytic enzymes, i.e., enolase 1, phosphoglycerate mutase 1 and triosephosphate isomerase 1. Using monoclonal antibodies directed against selected parts of HK molecule and synthetic peptides with sequences matching selected HK fragments, we assigned the major fungal cell wall-binding ability to a short stretch of amino acids in the C-terminal part of domain 3 and a large continuous region involving the C-terminal part of domain 5 and N-terminal part of domain 6 (residues 479-564). The latter characteristics of HK binding to C. albicans surface differ from those reported for bacteria and host cells.


Assuntos
Candida albicans/metabolismo , Parede Celular/metabolismo , Cininogênio de Alto Peso Molecular/metabolismo , Mapeamento de Interação de Proteínas/métodos , Sequência de Aminoácidos , Anticorpos Monoclonais/metabolismo , Sítios de Ligação , Candida albicans/efeitos dos fármacos , Candida albicans/enzimologia , Parede Celular/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida , Proteínas Fúngicas/metabolismo , Glucana 1,3-beta-Glucosidase/farmacologia , Humanos , Hifas/efeitos dos fármacos , Hifas/metabolismo , Espectrometria de Massas , Dados de Sequência Molecular , Fragmentos de Peptídeos/metabolismo , Fosfoglicerato Mutase/metabolismo , Fosfopiruvato Hidratase/química , Ligação Proteica , Estrutura Terciária de Proteína , Receptores de Superfície Celular/metabolismo , Triose-Fosfato Isomerase/metabolismo
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