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1.
Eur Heart J Case Rep ; 6(9): ytac357, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36111072

RESUMO

Background: The SARS-CoV-2 pandemic has led to the development of the first mRNA vaccines used in humans. These vaccines are well tolerated, safe, and highly effective; however, post-marketing surveillance is revealing potential rare adverse effects. We report a case of incessant pericarditis following administration of the second dose of mRNA-1273 SARS-CoV-2 vaccine, unresponsive to conventional therapy, and successfully treated with anakinra. Case summary: A 30-year-old man presented to the Emergency Department for incessant pericarditis unresponsive to evacuative pericardiocentesis and conventional first-line anti-inflammatory therapy. Given the typical 'inflammatory phenotype' clinically characterized by fever, C-reactive protein (CRP) elevation, and leucocytosis, we decided, in agreement with the rheumatologist team, to avoid glucocorticoid and to administer anakinra. A sudden clinical and echocardiographic improvement was observed, with complete resolution of the symptoms and of the pericardial effusion; similarly, CRP values progressively decreased. The patient was discharged at home; no recurrences of pericarditis were described at clinical and instrumental follow-up made 3 months later. Discussion: Several cases of pericarditis have been described in patients who received the COVID-19 vaccination, especially with the mRNA vaccine that can induce a non-adaptive immunity response against the viral spike protein, triggering cardiac damage for a molecular mimicry mechanism; however, defined pathogenesis of pericarditis associated with mRNA vaccine is still missing. The clinical scenario described is characterized by the typical 'inflammatory phenotype', triggered by a disproportionate and uncontrolled activation of the inflammasome based on an interleukin-1 (IL-1) overproduction. We administered anakinra, an IL-1 blocking drug, with a sharp clinical, echocardiographic and laboratoristic improvement. The complete response observed in this case suggests that vaccine-related pericarditis could be triggered by an auto-inflammatory pathway based on IL-1 overproduction. Further research is, therefore, warranted to determine the mechanisms by which the mRNA vaccine may cause pericarditis in order to choose the most targeted therapy.

2.
Eur Rev Med Pharmacol Sci ; 25(8): 3296-3299, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33928617

RESUMO

OBJECTIVE: Ventricular septal defect (VSD) is an uncommon but frequently fatal complication following acute myocardial infarction. In medically treated patients, mortality rates exceed 90%, while the surgical repair is associated with better outcomes, even though optimal surgical timing is still under debate. CASE REPORT: We present the case of a 78-years-old man with no previous remarkable cardiological history admitted to our Emergency Department with the diagnosis of anterior ST-elevation myocardial infarction and significant reduction of left ventricular ejection fraction. The emergency coronary angiography showed sub-occlusion of the left anterior descending coronary artery, treated with stent implantation. The post-procedural echocardiography unveiled the presence of an apical VSD with a large left-to-right shunt, significant right ventricular overload and dysfunction. An intra-aortic balloon pump (IABP) was positioned and, after Heart Team evaluation, a delayed surgical approach was planned. As a bridge to the intervention Levosimendan infusion was administered, on top of IABP support, and a significant improvement in bi-ventricular function and pressure profiles was obtained. Cardiac surgery was successfully performed 9 days after the admission without periprocedural complications. CONCLUSIONS: This unique case supports the use of Levosimendan as a valid pharmacological strategy for perioperative management of VSD.


Assuntos
Simendana/uso terapêutico , Ruptura do Septo Ventricular/tratamento farmacológico , Idoso , Procedimentos Cirúrgicos Cardíacos , Humanos , Masculino , Simendana/administração & dosagem , Ruptura do Septo Ventricular/diagnóstico , Ruptura do Septo Ventricular/cirurgia
3.
Clin Exp Rheumatol ; 35(6): 1043-1046, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29148422

RESUMO

OBJECTIVES: To evaluate the association of adalimumab trough levels and anti-adalimumab antibodies with activity of uveitis in juvenile idiopathic arthritis-related uveitis. METHODS: This was a retrospective observational case series in a clinical setting at the Department of Ophthalmology, Helsinki University Hospital, Finland in 2014-2016. Thirty-one paediatric patients with chronic anterior juvenile idiopathic arthritis-related uveitis in 58 eyes and who had been on adalimumab ≥6 months were eligible for the study. Uveitis activity during adalimumab treatment, adalimumab trough levels and anti-adalimumab antibody levels were recorded. RESULTS: Anti-adalimumab antibody levels ≥12 AU /ml were detected in nine patients (29%). This level of anti-adalimumab antibodies was associated with a higher grade of uveitis (p<0.001), uveitis that was not in remission (p=0.001) and with lack of concomitant methotrexate therapy (p=0.043). In patients with anti-adalimumab antibody levels <12 AU/ml, higher serum trough levels did not associate with better control of uveitis (p=0.86). CONCLUSIONS: Adalimumab treatment might be better guided by monitoring anti-adalimumab antibody formation in treating JIA-related uveitis.


Assuntos
Adalimumab/imunologia , Anticorpos/sangue , Antirreumáticos/imunologia , Artrite Juvenil/complicações , Uveíte/tratamento farmacológico , Adalimumab/sangue , Adalimumab/uso terapêutico , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Estudos Retrospectivos , Falha de Tratamento
4.
Environ Technol ; 37(17): 2189-98, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26804243

RESUMO

The behaviour of pharmaceuticals related to the human immunodeficiency virus treatment was studied in the liquid phase of source-separated urine during six-month storage at 20°C. Six months is the recommended time for hygienization and use of urine as fertilizer. Compounds were spiked in urine as concentrations calculated to appear in urine. Assays were performed with separate compounds and as therapeutic groups of antivirals, antibiotics and anti-tuberculotics. In addition, urine was amended either with faeces or urease inhibitor. The pharmaceutical concentrations were monitored from filtered samples with solid phase extraction and liquid chromatography. The concentration reductions of the studied compounds as such or with amendments ranged from less than 1% to more than 99% after six-month storage. The reductions without amendments were 41.9-99% for anti-tuberculotics; <52% for antivirals (except with 3TC 75.6%) and <50% for antibiotics. In assays with amendments, the reductions were all <50%. Faeces amendment resulted in similar or lower reduction than without it even though bacterial activity should have increased. The urease inhibitor prevented ureolysis and pH rise but did not affect pharmaceutical removal. In conclusion, removal during storage might not be enough to reduce risks associated with the studied pharmaceuticals, in which case other feasible treatment practises or urine utilization means should be considered.


Assuntos
Antibacterianos/urina , Antivirais/urina , Feminino , Humanos , Masculino , Manejo de Espécimes , Fatores de Tempo
5.
J Water Health ; 13(4): 996-1005, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26608761

RESUMO

The study aimed to assess the efficacy of an integrated water safety plan (WSP) in controlling Legionella re-growth in a respiratory hydrotherapy system located in a spa centre, supplied with sulphurous water, which was initially colonized by Legionella pneumophila. Heterotrophic plate counts, Pseudomonas aeruginosa, Legionella spp. were detected in water samples taken 6-monthly from the hydrotherapy equipment (main circuit, entry to benches, final outlets). On the basis of the results obtained by the continuous monitoring and the changes in conditions, the original WSP, including physical treatments of water and waterlines, environmental surveillance and microbiological monitoring, was integrated introducing a UV/ultrafiltration system. The integrated treatment applied to the sulphurous water (microfiltration/UV irradiation/ultrafiltration), waterlines (superheated stream) and distal outlets (descaling/disinfection of nebulizers and nasal irrigators), ensured the removal of Legionella spp. and P. aeruginosa and a satisfactory microbiological quality over time. The environmental surveillance was successful in evaluating the hazard and identifying the most suitable preventive strategies to avoid Legionella re-growth. Ultrafiltration is a technology to take into account in the control of microbial contamination of therapeutic spas, since it does not modify the chemical composition of the water, thus allowing it to retain its therapeutic properties.


Assuntos
Banhos , Desinfetantes/farmacologia , Desinfecção/métodos , Legionella/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Microbiologia da Água , Banhos/instrumentação , Contagem de Colônia Microbiana , Monitoramento Ambiental , Ultrafiltração/métodos , Raios Ultravioleta
6.
J Sep Sci ; 37(3): 219-27, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24347433

RESUMO

An analytical method for the simultaneous screening of three antiviral agents (nevirapine, zidovudine, lamivudine), four antibiotics (sulfamethoxazole, trimethoprim, ciprofloxacin, rifampicin) and one reference compound (carbamazepine) in human urine was developed. Separation was achieved with a Kinetex XB-C18 (75 × 4.6 mm, 2.6 µm) column after the extraction of pharmaceuticals from urine with SPE. Gradient elution with a mobile phase consisting of acetonitrile and 10 mM KH2 PO4 (pH 2.5), and diode array detection with monitoring at 210 and 264 nm was applied. The developed method was validated in terms of selectivity, linearity, stability and sensitivity. Repeatability (n = 3) and between-day precision (n = 3) revealed RSD <5%. The detection limits were estimated as 0.02-0.54 g/L (depending on compound). The method was validated for human urine and successfully applied to the simultaneous quantification of selected compounds. Strata-X cartridges provided good recoveries ranging from 81 to 109%. The limits of detection for urine varied between 0.04 and 1.61 g/L. The method is suitable for the fast determination of selected pharmaceuticals from source-separated urine samples for further environmental risk assessment and degradation potential evaluation. It provides a way to enhance safe nutrient recycling from wastewater streams and promotes the safe use of urine as fertiliser.


Assuntos
Antibacterianos/urina , Antivirais/urina , Cromatografia Líquida de Alta Pressão/métodos , Antibacterianos/sangue , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antivirais/sangue , Antivirais/química , Antivirais/isolamento & purificação , Humanos , Extração em Fase Sólida
7.
BMC Med Genet ; 11: 50, 2010 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-20353565

RESUMO

BACKGROUND: In search for genes predisposing to osteoarthritis (OA), several genome wide scans have provided evidence for linkage on 2q. In this study we targeted a 470 kb region on 2q11.2 presenting the locus with most evidence for linkage to severe OA of distal interphalangeal joints (DIP) in our genome wide scan families. METHODS: We genotyped 32 single nucleotide polymorphisms (SNPs) in this 470 kb region comprising six genes belonging to the interleukin 1 superfamily and monitored for association with individual SNPs and SNP haplotypes among severe familial hand OA cases (material extended from our previous linkage study; n = 134), unrelated end-stage bilateral primary knee OA cases (n = 113), and population based controls (n = 436). RESULTS: Four SNPs in the IL1R1 gene, mapping to a 125 kb LD block, provided evidence for association with hand OA in family-based and case-control analysis, the strongest association being with SNP rs2287047 (p-value = 0.0009). CONCLUSIONS: This study demonstrates an association between severe hand OA and IL1R1 gene. This gene represents a highly relevant biological candidate since it encodes protein that is a known modulator of inflammatory processes associated with joint destruction and resides within a locus providing consistent evidence for linkage to hand OA. As the observed association did not fully explain the linkage obtained in the previous study, it is plausible that also other variants in this genome region predispose to hand OA.


Assuntos
Articulação da Mão , Osteoartrite/genética , Receptores Tipo I de Interleucina-1/genética , Adulto , Idoso , Alelos , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Articulação da Mão/patologia , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Osteoartrite/patologia , Polimorfismo de Nucleotídeo Único , Índice de Gravidade de Doença
8.
Ann Surg ; 249(3): 384-7, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19247022

RESUMO

OBJECTIVE: To compare the Lichtenstein hernioplasty with a totally extraperitoneal preperitoneal laparoscopic technique (TEP) in treatment of recurrent inguinal hernias. SUMMARY BACKGROUND DATA: Only a few studies thus far have compared an open and laparoscopic approach with the treatment of recurrent inguinal hernia in a prospective randomized study setting. METHODS: Ninety-nine patients undergoing surgery for recurrent inguinal hernia were prospectively randomized into having either open or laparoscopic mesh repair. Pre, peri- and postoperative factors were recorded in addition to 3-year follow-up data at the outpatient clinic. At 5-10 years, the patients were interviewed via telephone for recurrent symptoms. The primary end-points chosen were hernia recurrence and chronic pain. RESULTS: Preoperative factors did not differ between the 2 groups. Rerecurrence rates were 3 in the Lichtenstein group and none in the TEP group (6.4% versus 0.0%, respectively), but this difference was statistically not significant. Chronic pain was more prevalent in the Lichtenstein group compared with the TEP group (13 [27.7%] versus 4 [8.2%] patients, respectively, P = 0.02). Postoperatively, the Lichtenstein group needed more pain medication than the TEP group (4.4 versus 3.0 doses, respectively, P = 0.02) and returned to work later (17.9 versus 14.8 days, respectively, P = 0.05). CONCLUSIONS: The laparoscopic technique with mesh in the treatment of recurrent inguinal hernia was proven superior to the open mesh repair in several important clinical aspects, with concomitant improvement in patient satisfaction.


Assuntos
Hérnia Inguinal/cirurgia , Procedimentos Cirúrgicos Operatórios/métodos , Adulto , Idoso , Feminino , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Reoperação , Telas Cirúrgicas
9.
Med Chem ; 3(6): 520-32, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18045201

RESUMO

A series N,N'-bis[4-(1H(2H)-benzotriazol-1(2)-yl)phenyl]alkyldicarboxamides (3a-f and 5a-j) were prepared starting from their already known (1a-d) and (4a-c) or new (4d) amine parents. Because of the antiviral activity of several N-[4-(1H(2H)-benzotriazol-1(2)-yl)phenyl]alkylcarboxamides previously reported, title compounds were evaluated in vitro for cytotoxicity and antiviral activity against viruses representative of Picornaviridae, [i.e. Enterovirus Coxsackie B2 (CVB-2) and Polio (Sb-1)] and of two of the three genera of the Flaviviridae [Bovine Viral Diarrhea Virus (BVDV) and Yellow Fever Virus (YFV)]. Furthermore, because of the in silico activity against the RNA-dependent RNA-helicase of Polio 1 previously reported, title compounds were evaluated against the 3D model of the Sb-1 helicase and against the 2D model of the CVB-2 helicase. As a reference we used the antiviral and in silico activities of an imidazo counterpart of the title compounds, N,N'-bis[4-(2-benzimidazolyl)phenyl]alkyldicarboxamides (III) that other authors reported to be able to inhibit the corresponding enzyme of Hepatitis C Virus (HCV). In cell-based antiviral assays, N,N'-bis[4-(1H-benzotriazol-1-yl)phenyl]alkyldicarboxamides (3a-f) resulted completely inactive whereas the bis-5,6-dimethyl-benzotriazol-2-yl derivatives (5d-f) exhibited good activity against the Enteroviruses, (EC(50)s ranged between 7 and 11 microM against CVB-2 and 19-52 against Sb-1). Interestingly, bis-5,6-dichloro-benzotriazol-2-yl derivatives (5h-j) showed very selective activity against CVB-2 (EC(50)s = 4-11 microM) whereas they resulted completely inactive against all the other viruses screened. In general, all title compounds showed a good cytotoxicity profile in MT-4 cells. Molecular modeling investigations showed that active compounds may interact with the binding site of the Sb-1 helicase and that their free binding energy values are in agreement with their EC(50)s values.


Assuntos
Amidas/síntese química , Antivirais/síntese química , Picornaviridae/efeitos dos fármacos , RNA Helicases/antagonistas & inibidores , Amidas/farmacologia , Antivirais/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Enterovirus/efeitos dos fármacos , Enterovirus/enzimologia , Flaviviridae/efeitos dos fármacos , Flaviviridae/enzimologia , Humanos , Picornaviridae/enzimologia , Relação Estrutura-Atividade
12.
Biochem Biophys Res Commun ; 336(1): 232-8, 2005 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-16129415

RESUMO

The presented green fluorescent protein and streptavidin core-based tripartite fusion system provides a simple and efficient way for the production of proteins fused to it in insect cells. This fusion protein forms a unique tag, which serves as a multipurpose device enabling easy optimization of production, one-step purification via streptavidin-biotin interaction, and visualization of the fusion protein during downstream processing and in applications. In the present study, we demonstrate the successful production, purification, and detection of a natural rubber latex allergen Hev b5 with this system. We also describe the production of another NRL allergen with the system, Hev b1, which formed large aggregates and gave small yields in purification. The aggregates were detected at early steps by microscopical inspection of the infected insect cells producing this protein. Therefore, this fusion system can also be utilized as a fast indicator of the solubility of the expressed fusion proteins and may therefore be extremely useful in high-throughput expression approaches.


Assuntos
Alérgenos/genética , Biotina/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas Recombinantes de Fusão/genética , Alérgenos/isolamento & purificação , Alérgenos/metabolismo , Animais , Antígenos de Plantas , Baculoviridae/genética , Sequência de Bases , Cromatografia de Afinidade , Primers do DNA , Ensaio de Imunoadsorção Enzimática , Proteínas de Fluorescência Verde/isolamento & purificação , Proteínas de Plantas , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Spodoptera
13.
J Mol Biol ; 342(4): 1197-208, 2004 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-15351645

RESUMO

The crystal structure of Delta3-Delta2-enoyl-CoA isomerase from human mitochondria (hmEci), complexed with the substrate analogue octanoyl-CoA, has been refined at 1.3 A resolution. This enzyme takes part in the beta-oxidation of unsaturated fatty acids by converting both cis-3 and trans-3-enoyl-CoA esters (with variable length of the acyl group) to trans-2-enoyl-CoA. hmEci belongs to the hydratase/isomerase (crotonase) superfamily. Most of the enzymes belonging to this superfamily are hexamers, but hmEci is shown to be a trimer. The mode of binding of the ligand, octanoyl-CoA, shows that the omega-end of the acyl group binds in a hydrophobic tunnel formed by residues of the loop preceding helix H4 as well as by side-chains of the kinked helix H9. From the structure of the complex it can be seen that Glu136 is the only catalytic residue. The importance of Glu136 for catalysis is confirmed by mutagenesis studies. A cavity analysis shows the presence of two large, adjacent empty hydrophobic cavities near the active site, which are shaped by side-chains of helices H1, H2, H3 and H4. The structure comparison of hmEci with structures of other superfamily members, in particular of rat mitochondrial hydratase (crotonase) and yeast peroxisomal enoyl-CoA isomerase, highlights the variable mode of binding of the fatty acid moiety in this superfamily.


Assuntos
Isomerases de Ligação Dupla Carbono-Carbono/química , Sequência de Aminoácidos , Isomerases de Ligação Dupla Carbono-Carbono/metabolismo , Cristalografia por Raios X , Dodecenoil-CoA Isomerase , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Dobramento de Proteína , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
14.
J Biol Chem ; 279(35): 36715-9, 2004 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-15131113

RESUMO

Two distinct circularly permuted forms of chicken avidin were designed with the aim of constructing a fusion avidin containing two biotin-binding sites in one polypeptide. The old N and C termini of wild-type avidin were connected to each other via a glycine/serine-rich linker, and the new termini were introduced into two different loops. This enabled the creation of the desired fusion construct using a short linker peptide between the two different circularly permuted subunits. The circularly permuted avidins (circularly permuted avidin 5 --> 4 and circularly permuted avidin 6 --> 5) and their fusion, pseudotetrameric dual chain avidin, were biologically active, i.e. showed biotin binding, and also displayed structural characteristics similar to those of wild-type avidin. Dual chain avidin facilitates the development of dual affinity avidins by allowing adjustment of the ligand-binding properties in half of the binding sites independent of the other half. In addition, the subunit fusion strategy described in this study can be used, where applicable, to modify oligomeric proteins in general.


Assuntos
Avidina/química , Sequência de Aminoácidos , Animais , Sítios de Ligação , Biotina/química , Galinhas , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Endopeptidase K/farmacologia , Glicina/química , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Peptídeos/química , Ligação Proteica , Conformação Proteica , Desnaturação Proteica , Dobramento de Proteína , Estrutura Quaternária de Proteína , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Sensibilidade e Especificidade , Serina/química
15.
FEBS Lett ; 555(3): 449-54, 2003 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-14675754

RESUMO

In order to turn the subunit association and biotin binding of avidin into pH-sensitive phenomena, we have replaced individually three amino acid residues in avidin (Met96, Val115 and Ile117) with histidines in the 1-3 interface, and in combination with a histidine conversion in the 1-2 interface (Trp110). The single replacements Met96His and Val115His in the 1-3 interface were found to have a clear effect on the quaternary structure of avidin, since subunit associations of these mutants became pH-dependent. The histidine replacement in the 1-2 interface affected the biotin-binding properties of the mutants, in particular reversibility of binding and protein-ligand complex formation were pH-sensitive, as measured by IAsys biosensor and fluorescence correlation spectroscopy, respectively. The possibility of regulating the quaternary structure and function of avidin in a controlled and predictable manner, due to introduced interface histidines, will expand even further the range and versatility of the avidin-biotin technology.


Assuntos
Avidina/metabolismo , Biotina/metabolismo , Histidina/metabolismo , Substituição de Aminoácidos , Animais , Avidina/química , Avidina/genética , Baculoviridae/genética , Baculoviridae/metabolismo , Técnicas Biossensoriais/métodos , Biotina/química , Linhagem Celular , Histidina/química , Histidina/genética , Concentração de Íons de Hidrogênio , Insetos , Modelos Moleculares , Peso Molecular , Ligação Proteica , Estrutura Quaternária de Proteína , Subunidades Proteicas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Espectrometria de Fluorescência/métodos
16.
J Biol Chem ; 278(4): 2479-83, 2003 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-12446662

RESUMO

In this study we showed that tetrameric chicken avidin can be stabilized by introducing intermonomeric disulfide bridges between its subunits. These covalent bonds had no major effects on the biotin binding properties of the respective mutants. Moreover, one of the mutants (Avd-ccci) maintained its tetrameric integrity even in denaturing conditions. The new avidin forms Avd-ci and Avd-ccci, which have native --> denatured transition midpoints (T(m)) of 98.6 and 94.7 degrees C, respectively, in the absence of biotin, will find use in applications where extreme stability or minimal leakage of subunits is required. Furthermore, we showed that the intramonomeric disulfide bridges found in the wild-type avidin affect its stability. The mutant Avd-nc, in which this bridge was removed, had a lower T(m) in the absence of biotin than the wild-type avidin but showed comparable stability in the presence of biotin.


Assuntos
Avidina/química , Avidina/genética , Biotina/química , Animais , Calorimetria , Linhagem Celular , Galinhas , Cisteína/química , DNA Complementar/metabolismo , Dissulfetos , Relação Dose-Resposta a Droga , Insetos , Isoleucina/química , Modelos Moleculares , Mutação , Ligação Proteica , Conformação Proteica , Desnaturação Proteica , Temperatura , Fatores de Tempo
17.
J Biol Chem ; 278(6): 4010-4, 2003 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-12458212

RESUMO

Homotetrameric chicken avidin that binds four molecules of biotin was converted to a monomeric form (monoavidin) by mutations of two interface residues: tryptophan 110 in the 1 --> 2 interface was mutated to lysine and asparagine 54 in the 1 --> 4 interface was converted to alanine. The affinity for biotin binding of the mutant decreased from K(d) approximately 10(-15) m of the wild-type tetramer to K(d) approximately 10(-7) m, which was studied by an optical biosensor IAsys and by a fluorescence spectroscopical method in solution. The binding was completely reversible. Conversion of the tetramer to a monomer results in increased sensitivity to proteinase K digestion. The antigenic properties of the mutated protein were changed, such that monoavidin was only partially recognized by a polyclonal antibody whereas two different monoclonal antibodies entirely failed to recognize the avidin monomer. This new monomeric avidin, which binds biotin reversibly, may be useful for applications both in vitro and in vivo. It may also shed light on the effect of intersubunit interactions on the binding of ligands.


Assuntos
Avidina/química , Animais , Avidina/genética , Avidina/isolamento & purificação , Avidina/metabolismo , Baculoviridae/genética , Biopolímeros , Biotina/metabolismo , Galinhas , Cromatografia em Gel , Ensaio de Imunoadsorção Enzimática , Modelos Moleculares , Mutagênese , Ligação Proteica , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo
19.
Ann Ist Super Sanita ; 37(3): 443-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11889962

RESUMO

We performed a review of the current literature in order to evaluate clinical, electrocardiographic and electrophysiologic parameters predictive of atrial fibrillation development. Clinical parameters were obtained from two large observational studies (the Framingham heart study and the Cardiovascular health study). Different laboratoristic predictors were also reviewed: ECG-derived predictors, among which we separately evaluated those derived from the 12-lead surface ECG and those derived from the signal averaged P-wave, and other electrophysiologic predictors as atrial monophasic action potential analysis. We also evaluated the clinical value of these different parameters in atrial fibrillation in patients with no overt structural heart disease and in the most common clinical conditions known to be related to atrial fibrillation development such as hypertension, heart failure, cardiovascular surgery.


Assuntos
Fibrilação Atrial/fisiopatologia , Eletrocardiografia , Eletrofisiologia , Humanos
20.
Circulation ; 101(10): 1102-8, 2000 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-10715255

RESUMO

BACKGROUND: Enhanced coronary vasomotion may contribute to acute coronary occlusion during the acute phase of myocardial infarction (AMI). Japanese have a higher incidence of variant angina than Caucasian patients, but racial differences in vasomotor reactivity early after AMI are controversial. METHODS AND RESULTS: The same team studied 15 Japanese and 19 Caucasian patients within 14 days of AMI by acetylcholine injection into non-infarct-related (NIRA) and infarct-related (IRA) coronary arteries followed by nitroglycerin. Incidence of vasodilation, vasoconstriction, spasm, and basal tone were assessed in proximal, middle, and distal segments after each drug bolus by quantitative angiography. Japanese patients had much lower cholesterol levels than Caucasians (183+/-59 versus 247+/-53 mg/dL, P<0.006) but showed a lower incidence of vasodilation (2% versus 9% of coronary segments) and a greater incidence of spasm after acetylcholine (47% versus 15% of arteries, P<0.00001). Incidence of spasm was higher in IRAs than in NIRAs in both populations (67% versus 39% and 23% versus 11%, respectively). Multivessel spasm was more common (64% versus 17%, P<0.02) and vasoconstriction of nonspastic segments was greater in Japanese patients (-23.4+/-14.9% versus -20.1+/-15.7%, P<0.02) in the presence of similar average basal coronary tone with respect to post-nitroglycerin dilation and of nonsignificant differences of coronary atherosclerotic score. CONCLUSIONS: Soon after AMI, Japanese patients exhibited a 3-fold-greater incidence of spasm and greater vasoconstriction of nonspastic segments after acetylcholine than Caucasians. The causes of such differences warrant further investigation because they may have relevant pathophysiological and therapeutic implications.


Assuntos
Povo Asiático , Vasoespasmo Coronário/etnologia , Infarto do Miocárdio/etnologia , População Branca , Acetilcolina/administração & dosagem , Idoso , Angiografia , Arteriosclerose/epidemiologia , Arteriosclerose/etiologia , Vasoespasmo Coronário/epidemiologia , Vasoespasmo Coronário/etiologia , Feminino , Humanos , Incidência , Itália/epidemiologia , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/epidemiologia , Vasoconstrição , Sistema Vasomotor/fisiopatologia
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