Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 171
Filtrar
1.
Clin Chim Acta ; 555: 117800, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38309557

RESUMO

BACKGROUND: Carbohydrate deficient transferrin (CDT) is a biomarker for excessive alcohol consumption utilized in clinical and forensic medicine and workplace testing. Previously, many different analytical methods for CDT were used and the measurand varied considerably, making direct comparison of test results difficult. To end this confusion, the IFCC established a working group on CDT standardisation (WG-CDT) which completed its tasks in 2017. METHODS: This IFCC position paper by the WG-CDT summarizes state of the art information about the measurand and the analytical methods and gives concise recommendations for its utilization. RESULTS: The results achieved by the CDT standardisation process led to accuracy improvements in national external quality assessment schemes over the years. A brief review of ROC based comparison studies with the traditional biomarkers (GGT, MCV, ALT and AST) discusses the bias resulting from inadequate study populations. In large groups of the general population the superior diagnostic performance of CDT is confirmed. CONCLUSION: The relationship between alcohol intake versus resulting CDT is discussed as well as the cutoff and measurement uncertainty. Concerning the application in practice, potential pitfalls are considered and recommendations handling both analytical and preanalytical caveats are given. Finally, some examples of serious misunderstandings in publications about CDT are addressed.


Assuntos
Consumo de Bebidas Alcoólicas , Humanos , Padrões de Referência , Biomarcadores
3.
Forensic Sci Med Pathol ; 18(4): 549-553, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36129618

RESUMO

A 17-year-old male with no previous medical history was admitted 2 days before his death to a local hospital after mild dyspnea. Electrocardiography, chest radiography, and blood analysis revealed no abnormalities. Blood oxygen saturation was 99%, and SARS-CoV-2 nasopharyngeal swabs tested negative; thus, he was discharged without prescriptions. After 2 days, the subject died suddenly during a pool party. Forensic autopsy was performed analyzing all anatomical districts. Cardiac causes were fully excluded after deep macroscopic and microscopic evaluation; lung and brain analyses showed no macroscopic pathology. Finally, a large subglottic solid mass was detected. The whitish neoplasm showed an aggressive invasion pattern to the thyroid and adjacent deep soft tissues and occluded the trachea. High-power microscopy showed sheets of small, uniform cells with scant cytoplasm; round nuclei; and small, punctate nucleoli, with immunohistochemical expression of CK8-18, AE1/AE3, and CD99. Using FISH analysis, the break-apart molecular probes (EWSR1 (22q12) Break - XL, Leica Biosystem, Nussloch, Germany) showed distinct broken red and green fluorochromes, diagnostic of Ewing sarcoma. The neoplasm was characterized as adamantinoma-like Ewing sarcoma, and the mechanism of death was identified as airway obstruction. The rarity of the case resides in the circumstances of death, which pointed to the possibility of sudden unexpected death due to heart disease, but an oncological cause and the underlying mechanism were finally diagnosed. The best method to perform autopsies is still complete, extensive, and systematic macroscopic sampling of organs and districts followed by histopathological analysis, in addition to immunohistochemical and molecular investigations in those cases in which they are necessary. In fact, when neoplasms are detected, the application of advanced techniques such as immunohistochemistry and molecular diagnostics is fundamental to accurately certify death.


Assuntos
Adamantinoma , COVID-19 , Sarcoma de Ewing , Masculino , Humanos , Sarcoma de Ewing/diagnóstico , Sarcoma de Ewing/metabolismo , Sarcoma de Ewing/patologia , Adamantinoma/patologia , SARS-CoV-2 , Imuno-Histoquímica , Biomarcadores Tumorais/metabolismo
4.
J Pharm Biomed Anal ; 147: 2-12, 2018 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-28912047

RESUMO

The need for investigating alcohol abuse by means of objective tools is worldwide accepted. Among the currently available biomarkers of chronic alcohol abuse, carbohydrate-deficient transferrin (CDT) is one of the most used indicator, mainly because of its high specificity. However, some CDT analytical and interpretation aspects are still under discussion, as witnessed by numerous research papers and reviews. The present article presents a critical review of the literature on CDT appeared in the period from 2007 to 2017 (included). The article is organized in the following sections: (1) introduction, (2) pre-analytical aspects (3) analytical aspects (4) diagnostic aspects (5) concluding remarks. As many as 139 papers appeared in the international literature and retrieved by the search engines PubMed, Web of Science and Scopus are quoted.


Assuntos
Alcoolismo/diagnóstico , Biomarcadores/sangue , Transferrina/análogos & derivados , Alcoolismo/sangue , Cromatografia Líquida de Alta Pressão , Eletroforese Capilar , Humanos , Sensibilidade e Especificidade , Transferrina/análise
5.
Int J Pharm ; 514(1): 229-237, 2016 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-27863666

RESUMO

In this work nasal powder formulations of thalidomide were designed and studied to be used by persons affected by hereditary hemorrhagic telangiectasia as a complementary anti-epistaxis therapy, with the goal of sustaining the effect obtained with thalidomide oral treatment after its discontinuation for adverse effects. Three nasal powders were prepared using as carriers ß-CD or its more hydrophilic derivatives such as hydropropyl-ß-CD and sulphobutylether-ß-CD and tested with respect to technological and biopharmaceutical features after emission with active and passive nasal powder devices. For all formulated powders, improved dissolution rate was found compared to that of the raw material, making thalidomide promptly available in the nasal environment at a concentration favouring an accumulation in the mucosa. The very limited transmucosal transport measured in vitro suggests a low likelihood of significant systemic absorption. The topical action on bleeding could benefit from the poor absorption and from the fact that about 2-3% of the thalidomide applied on the nasal mucosa was accumulated within the tissue, particularly with the ß-CD nasal powder.


Assuntos
Epistaxe/tratamento farmacológico , Pós/administração & dosagem , Telangiectasia Hemorrágica Hereditária/tratamento farmacológico , Talidomida/administração & dosagem , Administração Intranasal , Animais , Química Farmacêutica/métodos , Portadores de Fármacos/química , Humanos , Mucosa Nasal/efeitos dos fármacos , Coelhos , Solubilidade , beta-Ciclodextrinas/administração & dosagem
6.
J Oral Rehabil ; 40(7): 509-18, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23675909

RESUMO

In recent years, there has been increasing interest in the relationship between dental occlusion and body posture both among people and in scientific literature. The aim of the present longitudinal study is to investigate the effects of an experimental occlusal interference on body posture by means of a force platform and an optoelectronic stereophotogrammetric analysis. An occlusal interference of a 0- to 2-mm-thick glass composite was prepared to disturb the intercuspal position while not creating interference during lateral or protrusive mandibular excursions. Frontal and sagittal kinematic parameters, dynamic gait measurements and superficial electromyographic (SEMG) activity of head and neck muscles were performed on 12 healthy subjects. Measurements were taken 10 days before the application of the occlusal interference, and then immediately before the application, the day after it, and at a distance of 7 and 14 days under four different exteroceptive conditions. The outcomes of this study show that an occlusal interference does not modify significantly over time static and dynamic parameters of body posture under different exteroceptive conditions. It has a minimal influence only on the frontal kinematic parameters related to mandibular position, and it induces a transient increase of the activity of masticatory muscles. In this study, the experimental occlusal interference did not significantly influence the body posture during a 14-day follow-up period.


Assuntos
Marcha/fisiologia , Má Oclusão/fisiopatologia , Músculos da Mastigação/fisiopatologia , Músculos do Pescoço/fisiopatologia , Postura/fisiologia , Músculos Superficiais do Dorso/fisiopatologia , Eletromiografia , Feminino , Humanos , Estudos Longitudinais , Masculino , Fotogrametria , Adulto Jovem
7.
Curr Med Chem ; 19(33): 5658-63, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22856660

RESUMO

Cocaine is one of the most used psychomotor stimulants all over the world. On this basis, the interest for the pharmacological activity and the pharmacodynamic and pharmacokinetic aspects of this drug is very prominent in both clinical and forensic toxicological environments. The review presents and discusses 65 scientific publications covering all the aspects of cocaine toxicokinetic, including absorption, distribution, metabolism and elimination of the drug. Particular attention has been dedicated to the studies on the disposition of the drug in alternative biological matrices, such as oral fluid, hair, fetus fluids and tissues, and sweat. In fact, in the last years the use of these matrices has been proposed in clinical and forensic drug analysis in order to obtain additional information to that which can be obtained by analyzing the traditional biological matrices, such as blood and urine.


Assuntos
Cocaína/farmacocinética , Inibidores da Captação de Dopamina/farmacocinética , Animais , Cocaína/metabolismo , Cocaína/toxicidade , Inibidores da Captação de Dopamina/metabolismo , Inibidores da Captação de Dopamina/toxicidade , Toxicologia Forense/métodos , Cabelo/metabolismo , Humanos , Saliva/metabolismo , Detecção do Abuso de Substâncias/métodos
8.
Forensic Sci Rev ; 23(2): 55-72, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26231235

RESUMO

Alcohol abuse represents a highly relevant medical, social, and economic problem all over the world. The diagnosis of conditions of alcohol use or abuse is complex, requiring different and integrated methodologies; among them the use of biomarkers is a very helpful and objective tool. This review article discusses the currently available biomarkers of alcohol abuse, showing their positive and negative characteristics in terms of detection window, diagnostic sensitivity, diagnostic specificity, and analytical feasibility. Particular attention is dedicated to the most used biomarkers, represented by liver enzymes (AST, ALT, and GGT), MCV, CDT, EtG and EtS, FAEE, and PEth. A critical analysis of the different biomarkers showed wide variability in terms of detection window, sensitivity, and specificity. On this basis, the choice of any indicator should depend on the aim and context for which the diagnosis of alcohol abuse is required (e.g., clinical, fitness for driver's license, fitness to work, child custody). Moreover, this study showed that the diagnosis of alcohol abuse cannot be based only on the use of biomarkers, but it must also consider the integration of anamnestic, clinical, instrumental, and laboratory data.

9.
J Viral Hepat ; 15(4): 246-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18248333

RESUMO

About 30% of the patients with chronic hepatitis develop a progressive liver disease and one of the most intriguing issues is the detection of noninvasive markers for fibrosis stage and disease progression. High levels of squamous cell carcinoma antigen (SCCA)-immunoglobulin M (IgM) are detectable in hepatocellular carcinoma and their increase in cirrhotic patients can predict tumour development. As SCCA-IgM can also be detectable at low percentages in patients with chronic hepatitis, the aim of this study was to assess SCCA-IgM complexes in relation to disease outcome in this group of patients. An ELISA assay was used to determine the presence of SCCA-IgM in 188 patients with chronic hepatitis and in 100 controls. An additional serum sample was available after a median period of 6 years in 57 untreated patients: these patients were subdivided in group A, including eight patients with a fibrosis score increase > or =2 in a second liver biopsy and group B, including 49 patients without fibrosis progression during a similar follow up. SCCA-IgM complexes were detectable in 63 of 188 (33%) patients but in none of the controls. A significant increase of SCCA-IgM levels over time was observed in patients with fibrosis progression (mean +/- SD: 117 +/- 200 U/mL/year), but not in those without histologic deterioration (mean +/- SD: -8.8 +/- 31 U/mL/year, P < 0.0001). In conclusion, monitoring SCCA-IgM levels over time appears a useful approach to identify patients with chronic hepatitis at higher risk for cirrhosis development.


Assuntos
Complexo Antígeno-Anticorpo/sangue , Antígenos de Neoplasias/imunologia , Hepatite Crônica/complicações , Imunoglobulina M/imunologia , Cirrose Hepática/diagnóstico , Serpinas/imunologia , Adulto , Biomarcadores , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Hepatite Crônica/patologia , Humanos , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade
10.
Scand J Clin Lab Invest ; 67(2): 191-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17365998

RESUMO

OBJECTIVE: There is a paucity of studies on quantitative determination of carbohydrate-deficient transferrin (CDT) in newborns. The aim of our study was therefore to determine CDT concentrations in newborns by using capillary zone electrophoresis (CZE). MATERIAL AND METHODS: Capillary blood was collected from the heels of 28 at-term healthy newborns, simultaneously with the Guthrie card screening. Forty-seven adults were examined as controls. CZE separations were performed with a P/ACE MDQ capillary electropherograph in uncoated fused-silica capillaries using a commercial reagent kit. After iron saturation, the samples were loaded by application of 0.5 psi for 15 s, and separated under 28kV with UV detection. All relevant transferrin (Tf) glycoforms were separated within 7 min. CDT quantification (%CDT) was carried out by calculating the percentage ratio between the sum of the peak areas of CDT-related glycoforms and the sum of peak areas of all Tf glycoforms. RESULTS: In most cases, good separations of Tf glycoforms were obtained. In the newborns the %CDT was 0.51 versus 0.66 in adults (difference not statistically significant). Trisialo-Tf concentration was significantly lower in newborns (3.20) than in adults (4.11). Furthermore, pentasialo-Tf appeared to be lower in newborns (7.30) than in adults (14.00), but because complete separation of the peaks of tetrasialo- and pentasialo-Tf was not always possible, this finding could not be confirmed statistically. CONCLUSIONS: CZE showed definite advantages in terms of volume of blood to be collected, simplicity and standardization of analysis and, because of the direct detection of the separated zones, accuracy of quantification. The present study provides the basic information in the search for glycosylation defects in newborns.


Assuntos
Eletroforese Capilar/métodos , Microquímica/métodos , Transferrina/análogos & derivados , Adulto , Biomarcadores/sangue , Feminino , Humanos , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Temperança , Transferrina/análise
11.
Int J Pharm ; 330(1-2): 129-37, 2007 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-17027206

RESUMO

Poly(vinyl alcohol) (PVA) microspheres were prepared by dispersion reticulation with glutaraldehyde and further aminated. These microspheres were firstly loaded with diclofenac (DF) and then entrapped in cellulose acetate butyrate (CAB) microcapsules by an o/w solvent evaporation technique for intestinal delivery of drug. The encapsulated PVA microspheres due to their low swelling degree in intestinal fluids, do not have enough force to produce the disruption of CAB shell, therefore different amounts of succinoylated pullulan microspheres (SP-Ms) (exchange capacity up to 5.2 meq/g) were co-encapsulated. The SP-Ms do not swell in acidic pH, but swell up to 20-times in intestinal fluids causing the rupture of CAB shell and facilitating the escape of loaded PVA microspheres.


Assuntos
Anti-Inflamatórios não Esteroides/química , Sistemas de Liberação de Medicamentos , Glucanos/química , Álcool de Polivinil/química , Anidridos Succínicos/química , Tecnologia Farmacêutica/métodos , Anti-Inflamatórios não Esteroides/administração & dosagem , Cápsulas/síntese química , Celulose/análogos & derivados , Celulose/química , Diclofenaco/administração & dosagem , Diclofenaco/química , Cinética , Microscopia Eletrônica de Varredura , Microesferas , Succinatos/química
12.
Int J Pharm ; 336(1): 133-9, 2007 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-17184941

RESUMO

We have previously demonstrated that dopamine conjugation to glucose allows it to induce therapeutic effects against Parkinson's disease after intravenous administration. In this paper we demonstrate that, unlike dopamine, the prodrug glu-dopamine is a transportable substrate of glucose transporters. Towards this, the effect of glucose-conjugation on the affinity and uptake of dopamine have been assessed in vitro, using human retinal pigment epithelium (HRPE) cells. Glucose transporter-mediated uptake was measured using [(3)H]3-O-methylglucose ([(3)H]3-O-MG) as the tracer. The uptake was found to be rapid and hyperbolically related to its concentrations (K(t)=7.8+/-1.2mM and V(max)=54+/-2 nmol/min mg protein). Inhibition experiments showed that dopamine was able to interact with glucose carriers only when conjugated to glucose (IC(50)=2.6+/-0.6mM). HPLC analysis of HRPE cell extracts showed that both dopamine and the prodrug permeate the cell, but only the uptake of the prodrug is inhibitable by glucose. This confirms that glucose transporters mediate the transport of the prodrug glu-dopamine, but not of dopamine. HRPE cells is therefore proposed as a promising model for in vitro studies involving the glucose transporter-mediated transport of drugs and their conjugates.


Assuntos
Dopamina/metabolismo , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Glucose/metabolismo , Pró-Fármacos/metabolismo , 3-O-Metilglucose/metabolismo , Transporte Biológico , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Dopamina/química , Dopamina/farmacocinética , Células Epiteliais/química , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Glucose/química , Glucose/farmacocinética , Humanos , Cinética , Estrutura Molecular , Epitélio Pigmentado Ocular/citologia , Pró-Fármacos/farmacocinética
13.
Infection ; 34(2): 62-5, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16703294

RESUMO

BACKGROUND: Hepatitis C virus (HCV) circulates as a mixture of different but closely related genomes: this quasispecies nature could be essential for virus persistence and could induce resistance to interferon therapy. Since little is known on the behavior of HCV quasispecies in children and adolescents with chronic hepatitis C, we analyzed the virus population in six untreated children during a 5-year follow-up. METHODS: Six children aged 1-8 years, infected early in life with HCV, were included in the study. From each of them, 2 or 3 sequential serum samples obtained over a 5-year follow-up period were examined. The HCV quasispecies heterogeneity and diversity in the E2 hypervariable region-1 (HVR-1) were analyzed among samples by the heteroduplex mobility assay, and the distance between variants was estimated by the heteroduplex mobility ratio (HMR). RESULTS: The HCV population was initially highly homogeneous in all six children. During follow-up, diversification of HVR-1 leading to a more complex viral population occurred in all cases, and was particularly evident in the three older children (HMR: 0.82-0.54). Changes in the HVR-1 sequence occurred without relation to the profile of ALT and HCV-RNA levels. CONCLUSIONS: HCV quasispecies diversification is a common event during chronic hepatitis C in childhood. Host and environmental pressure could be major determinants. The increasing viral heterogeneity could impair the response to antiviral therapy, thus indicating a rationale for early antiviral treatment in children with chronic hepatitis C.


Assuntos
Evolução Molecular , Hepacivirus/classificação , Hepacivirus/genética , Hepatite C Crônica/virologia , Criança , Pré-Escolar , Feminino , Variação Genética , Análise Heteroduplex , Humanos , Lactente , Masculino , Reação em Cadeia da Polimerase/métodos , RNA Viral/sangue , Proteínas Virais/genética
14.
Int J Pharm ; 317(1): 90-100, 2006 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-16600535

RESUMO

In the present study the preparation, characterization and activity of cationic liposomes containing the secretory form of herpes simplex virus type 1 (HSV-1) glycoprotein B (gB1s) or two related polylysine rich peptides, namely DTK1 and DTK2, were described. The immunotherapeutic potential of these HSV antigens containing liposomes was examined with a rabbit ocular model of HSV-1 infection. Our study indicates that the liposomes (i) are able to encapsulate quantitatively gB1s and around 30% the DTK peptides, (ii) are characterized by dimensions compatible with ocular applications and (iii) can release the peptide comparably to the free solution. In addition, neutralization studies demonstrated that an anti-DTK specific polyclonal antiserum can inhibit HSV-1 infection, indicating that such peptides could be a good immunogen/antigen in an anti-HSV vaccine formulation. Although the vaccination protocol did not induce protection against the eye disease, a significative protection against a lethal ocular challenge was detectable together with the absence of reactivation episodes from latency on the survived animals. In this respect, the use of cationic liposomes coupled to gB1s and DTK peptides, as a local ocular vaccine, could represent an interesting approach in order to obtain a possible efficacy in protecting animals against a subsequent HSV-1 ocular challenge.


Assuntos
Vacinas contra o Vírus do Herpes Simples/administração & dosagem , Herpes Simples/prevenção & controle , Peptídeos/administração & dosagem , Proteínas do Envelope Viral/administração & dosagem , Animais , Chlorocebus aethiops , Sistemas de Liberação de Medicamentos , Olho/virologia , Feminino , Herpes Simples/virologia , Herpesvirus Humano 1/imunologia , Herpesvirus Humano 1/patogenicidade , Lipossomos , Peptídeos/síntese química , Coelhos , Células Vero
15.
Int J Pharm ; 307(1): 103-13, 2006 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-16289882

RESUMO

The prodrug 5'-octanoyl-CPA (Oct-CPA) of the antiischemic N6-cyclopentyladenosine (CPA) has been encapsulated by nanoprecipitation in poly(lactic acid) nanoparticles, which have been recovered by gel-filtration, ultra-centrifugation or dialysis. We have analysed how different surfactants and purification methods can influence the nanoparticle characteristics. The particle sizes have been obtained by scanning electron microscope, whereas a SdFFF system was employed to detect their distributions. The Oct-CPA release from nanoparticles and stabilities in human blood of free and encapsulated prodrug have been analysed by HPLC techniques. The effects of nanoparticles on CPA interaction toward adenosine A1 receptor (its action site) have been analysed using radiolabelled drugs. The smallest nanoparticles and the best degree of homogeneity have been obtained using sodium cholate; the best recovery has been achieved by dialysis, whereas gel-filtration and ultra-centrifugation have induced the greatest removal of surfactants. The release of Oct-CPA was better controlled from the nanoparticles obtained using Pluronic F68 and purified by gel-filtration or ultra-centrifugation. Similarly, these nanoparticles better increased the stability of the prodrug in human blood. In particular, the nanoparticles purified by ultra-centrifugation induced a strong stability to a fraction of the encapsulated Oct-CPA. Any interference by unloaded nanoparticles has been registered for CPA-adenosine A1 receptor interaction.


Assuntos
Adenosina/análogos & derivados , Isquemia/tratamento farmacológico , Nanoestruturas , Pró-Fármacos/química , Adenosina/sangue , Adenosina/química , Adenosina/farmacocinética , Agonistas do Receptor A1 de Adenosina , Células Cultivadas , Química Farmacêutica , Portadores de Fármacos , Estabilidade de Medicamentos , Humanos , Hidrólise , Tamanho da Partícula , Poloxâmero/química , Pró-Fármacos/metabolismo , Pró-Fármacos/farmacocinética , Receptor A1 de Adenosina/metabolismo , Colato de Sódio/química , Tensoativos/química
16.
Dig Liver Dis ; 37(12): 964-7, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16249128

RESUMO

We reported two cases of hepatitis B virus infection-related cirrhosis developed during childhood and followed up for more than 20 years. Both the subjects remained untreated, and ultimately regression of cirrhosis was documented by clinical (including ultrasound) and histological examination. Recent studies have already suggested that hepatitis B virus-related cirrhosis may regress after treatment, but this is the first demonstration that hepatitis B virus-associated cirrhosis developed in childhood may be a spontaneously reversible process. Subsidence of virus replication and of necro-inflammatory process and the efficiency of liver regeneration and repair might contribute to this favourable outcome.


Assuntos
Hepatite B/complicações , Cirrose Hepática/fisiopatologia , Regeneração Hepática/fisiologia , Fígado/patologia , Fatores Etários , Criança , Feminino , Humanos , Lactente , Cirrose Hepática/virologia , Masculino , Remissão Espontânea , Fatores de Tempo
17.
Cell Mol Life Sci ; 62(19-20): 2350-8, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16143823

RESUMO

Caffeine is the most widely used drug in the world and acts mainly through antagonism of the effects mediated by the adenosine receptor subtypes A1, A2A, A2B and A3. We determined whether repeated caffeine administration at different doses and for different periods of time (400 or 600 mg/day for 1 week and 400 mg/day for 2 weeks) alters human neutrophil A2A adenosine receptor density and function. Saturation binding assays showed an increase in affinity (K(D)) and density (B(max)) of A2A adenosine receptors after caffeine intake. These changes were accompanied by increases in cAMP accumulation and decreases in superoxide anion production after stimulation of the A2A receptor subtype using the agonist 5'-N-ethylcarboxamidoadenosine (NECA). Binding and functional changes of A2A receptors returned to baseline after 48 h of caffeine withdrawal. The findings are consistent with a potential anti-inflammatory effect of caffeine mediated by neutrophil A2A receptors.


Assuntos
Cafeína/farmacologia , Neutrófilos/efeitos dos fármacos , Receptor A2A de Adenosina/metabolismo , Agonistas do Receptor A2 de Adenosina , Adenosina-5'-(N-etilcarboxamida)/farmacologia , Adulto , Células Cultivadas , AMP Cíclico/metabolismo , Humanos , Masculino , Neutrófilos/metabolismo , Superóxidos/metabolismo
18.
Eur J Med Chem ; 40(5): 445-51, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15893018

RESUMO

We describe the synthesis and activities of a series of pseudopeptides containing an N-aryl-N'-hydroxyalkyl hydrazide core structure to inhibit human immunodeficiency virus protease and viral replication. Of the series, compound Hmb-Leu-N(Bzl)-N(CH2-CH-OH)-rPro-Boc (24) displayed the greatest inhibitory potency (IC50 < 1 microM) and exhibited enzymatic resistance and stability in vitro.


Assuntos
Inibidores da Protease de HIV/síntese química , Inibidores da Protease de HIV/farmacologia , HIV-1/efeitos dos fármacos , Hidrazinas/síntese química , Peptídeos/síntese química , Peptídeos/farmacologia , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/química , HIV-1/enzimologia , HIV-1/fisiologia , Humanos , Hidrazinas/química , Hidrazinas/farmacologia , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Peptídeos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacos
19.
Gut ; 54(6): 852-7, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15888796

RESUMO

BACKGROUND AND AIMS: Little is known of hepatitis C virus (HCV) genotypes in HCV infected children. This retrospective, multicentre study investigated genotype distribution and correlation with clinical features and outcome in a large series of Italian children. METHODS: Between 1990 and 2002, 373 HCV RNA positive children, consecutively recruited in 15 centres, were assayed for genotypes by a commercial line probe assay. RESULTS: The following genotype distribution pattern was recorded: genotype 1b = 41%; 1a = 20%; 2 = 17%; 3 = 14.5%; 4 = 5%; other = 2.5%. The prevalence of genotypes 1b and 2 decreased significantly (p<0.001) among children born from 1990 onwards compared with older children (46% v 70%) while the rate of genotypes 3 and 4 increased significantly (from 8% to 30%). Children infected with genotype 3 had the highest alanine aminotransferase levels and the highest rate of spontaneous viraemia clearance within the first three years of life (32% v 3% in children with genotype 1; p<0.001). Of 96 children enrolled in interferon trials during the survey, 22% definitely lost HCV RNA, including 57% of those with genotypes 2 and 3. CONCLUSION: HCV genotypes 1 and 2 are still prevalent among infected adolescents and young adults in Italy but rates of infection with genotypes 3 and 4 are rapidly increasing among children. These changes could modify the clinical pattern of hepatitis C in forthcoming years as children infected with genotype 3 have the best chance of spontaneous viraemia clearance early in life, and respond to interferon in a high proportion of cases.


Assuntos
Hepacivirus/genética , Hepatite C Crônica/genética , Adolescente , Alanina Transaminase/metabolismo , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Hepatite C Crônica/epidemiologia , Hepatite C Crônica/transmissão , Humanos , Lactente , Itália/epidemiologia , Masculino , Prognóstico , RNA Viral/análise , Estudos Retrospectivos
20.
Dig Liver Dis ; 37(5): 336-41, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15843083

RESUMO

BACKGROUND AND AIM: Large interferon-based therapeutic trials are still lacking in children with hepatitis C and the long-term safety and efficacy of interferon is unknown. This study describes the outcome of hepatitis C in 43 children enrolled in an open-label interferon trial, and were followed up to 66 months after stopping treatment. PATIENTS AND METHODS: All patients received interferon alfa2a (5MU/m(2)) thrice weekly for 6 months; children with genotype 1b received 3MU/m(2) thrice weekly for 6 additional months. RESULTS: Nine children discontinued interferon for adverse events and three were not compliant to treatment. Eight (19%, intention to treat analysis), including 2/20 (10%) with genotype 1b and 6/12 (50%) with genotypes 2 or 3, were sustained responders 12 months after stopping therapy. During further follow-up (mean+/-S.D.: 44.7+/-14.6 months), response was maintained; two non-responders cleared viremia, while a young boy progressed to cirrhosis. CONCLUSIONS: Small sample size and therapy withdrawal are the major limitations in the interpretation of our results. Nevertheless, our data, suggesting that response to interferon in children with hepatitis C is genotype-related and stable, agree with the results of large studies in adults. The outcome in non-responders was variable, including persistence of viremia and mild-moderate cytolysis (most cases), progression to cirrhosis, or eventual sustained viremia clearance.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Adolescente , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Progressão da Doença , Feminino , Hepacivirus/genética , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Interferon-alfa/efeitos adversos , Masculino , RNA Viral/análise , Proteínas Recombinantes , Indução de Remissão
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...