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1.
J Dairy Sci ; 104(12): 12679-12692, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34600712

RESUMO

Many of the metrics used to evaluate farm performance are only partial indicators of farm operations, which are assumed to be best predictors of the whole farm efficiency. The main objective of this work was to identify aggregated multiple indexes of profitability using common partial indicators that are routinely available from individual farms to better support the short-term decision-making processes of the cattle-feeding process. Data were collected from face-to-face interviews with farmers from 90 dairy farms in Italy and used to calculate 16 partial indicators that covered almost all indicators currently used to target feeding and economic efficiency in dairy farms. These partial indicators described feed efficiency, energy utilization, feed costs, milk-to-feed price ratio, income over feed costs, income equal feed cost, money-corrected milk, and bargaining power for feed costs. Calculations of feeding costs were based on lactating cows or the whole herd, and income from milk deliveries was determined with or without considering the milk quality payment. Multivariate factor analysis was then applied to the 16 partial indicators to determine simplified and latent structures. The results indicated that 5 factors explained 70% of the variability. Each of the original partial indicator was associated with all factors in different proportions, as indicated by loading scores from the multivariate factor analysis. Based on the loading scores, we labeled these 5 factors as "economic efficiency," "energy utilization," "break-even point," "milk-to-feed price," and "bargaining power of the farm," in decreasing order of explained communality. The first 3 factors shared 83% of the total communality. Feed efficiency was similarly associated with factor 1 (53% loading) and factor 2 (66% loading). Only factor 4 was significantly affected by farm location. Milk production and herd size had significant effects on factor 1 and factor 2. Our multivariate approach eliminated the problem of multicollinearity of partial indicators, providing simple and effective descriptions of farm feeding economics. The proposed method allowed the evaluation, benchmarking, and ranking of dairy herd performance at the level of single farms and at territorial level with high opportunity to be used or replicated in other areas.


Assuntos
Indústria de Laticínios , Lactação , Ração Animal , Animais , Bovinos , Fazendeiros , Fazendas , Feminino , Humanos , Leite
2.
J Biol Regul Homeost Agents ; 29(2 Suppl 1): 18-24, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26634583

RESUMO

Atopic dermatitis (AD) is a chronic inflammatory skin disease that commonly presents during early childhood. In the last decades the prevalence of AD has increased, especially in western societies. This frequently relapsing inflammatory condition has a strong impact on the quality of life of patients and families. The recent advances in the understanding of this disease have paved the way for the development of new strategies for the prevention and treatment of AD. Among the new therapeutic options, there is increasing interest in the potential benefit of probiotic supplementation. It has been widely demonstrated that the human microbiota plays a fundamental role not only in the maintenance of intestinal homeostasis through the interaction between microorganisms and the innate immune system, but also in the microbiota-mediated development of adaptive immunity. In addition, several studies have demonstrated that probiotics are able to influence the composition of gut microbiota and may exert immunomodulatory effects. According to these promising results, the possible application of probiotics in the therapeutic management of allergic diseases has been investigated in many studies. In particular, a considerable body of literature has been published analyzing the effects of probiotics on patients with AD. In order to shed light on frequently conflicting results, we reviewed the data regarding the application of probiotics in AD, with the aim to provide a state-of-the-art assessment of the most important studies exploring the role of probiotics both in the prevention and treatment of AD.

3.
J Biol Regul Homeost Agents ; 29(2 Suppl 1): 96-113, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26634595

RESUMO

Intestinal microbiota is composed by symbiotic innocuous bacteria and potential pathogens also called pathobionts. Even if the mechanism of action of intestinal bacteria remain still unknown, specific microbial species seem to have important role in the maintenance of immunological equilibrium in the gut through the direct interaction with immune cells. Some studies have found a dysregulated interaction between the intestinal bacteria, the gut barrier, and the intestinal associated immune system in Inflammatory Bowel Disease (IBD) patients and in the pathogenesis of these pathologies. In IBD patients some Butyrate producing bacteria, as Faecalibacterium Prausnitzii, are under represented and this could be related with their chronic inflammatory state.

4.
J Biol Regul Homeost Agents ; 28(1): 117-24, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24750797

RESUMO

Antibiotic therapy, especially in pediatric patients, is often associated with significant modifications of the gut microflora, which can lead to intestinal dysbiosis and influence intestinal physiology and immune system functionality. Herein we report the results from a double blind controlled clinical trial in 77 pediatric patients affected by recurrent airway infections, receiving antibiotic therapy with amoxicillin and clavulanic acid. A group was treated with an oral probiotic preparation composed of Lactobacillus paracasei ssp.paracasei CRL-431, Bifidobacterium BB-12, Streptococcus thermophilus TH-4 and a fructooligosaccharide (FOS) during and after antibiotic therapy for seven days, while the other group received placebo. The study revealed a reduction in the Clostridia population, with a contemporary increase in Bifidobacteria and Lactobacilli in fecal samples in the probiotic group and an increase in the Enterobacteria population in the placebo group. Moreover, there was a decreasing trend in secretory IgA production in the probiotic group. Some relevant, but not statistically significant probiotic supplementation effects were identified.


Assuntos
Antibacterianos/uso terapêutico , Imunoglobulina A Secretora/biossíntese , Intestinos/microbiologia , Probióticos/administração & dosagem , Infecções Respiratórias/tratamento farmacológico , Adolescente , Bifidobacterium , Criança , Pré-Escolar , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Lactente , Lactobacillus , Masculino , Placebos , Infecções Respiratórias/imunologia
5.
Eur J Nutr ; 52(3): 877-83, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22692502

RESUMO

PURPOSE: Lysozyme, obtained from egg white, is a potential food allergen used in the dairy industry to prevent late blowing of the loaf caused by the outgrowth of clostridial spores (Cl. butyricum and Cl. tyrobutyricum) during cheese aging. The aim of this study was to evaluate the possible correlation between egg protein allergy in pediatric age and sensitization to egg lysozyme, used for the preparation of Grana Padano cheese. METHODS: The tolerability of Grana Padano cheese has been evaluated in pediatric patients allergic to egg proteins through an oral provocation test with increasing amounts of cheese containing, or not, lysozyme at 12 and 24 months of aging. RESULTS: When lysozyme-sensitized children received 12-months aged and lysozyme-containing cheese, several immediate and late adverse reactions such as itching, abdominal pain, vomiting, nausea, dermatitis, rhinitis, bronchial asthma, urticaria, and angioedema were seen in 5 out of 21 subjects; only 1 out of 21 children showed an adverse reaction after challenge with 24-months-ripened lysozyme-containing cheese. CONCLUSIONS: There is a possible relationship between the severity of allergic reactions and the lysozyme-specific IgE level in blood. In particular vomiting, hypotension, and abdominal pain were present when IgE level was higher than 7 kU/L. A ripening time of 24 months may reduce allergy problems when lysozyme-containing cheese is given to sensitized subjects, probably due to the hydrolysis of antigenic epitopes during aging.


Assuntos
Antígenos/efeitos adversos , Queijo/efeitos adversos , Dieta/etnologia , Hipersensibilidade a Ovo/imunologia , Manipulação de Alimentos , Muramidase/efeitos adversos , Adolescente , Antígenos/metabolismo , Queijo/análise , Queijo/microbiologia , Criança , Pré-Escolar , Clostridium butyricum/crescimento & desenvolvimento , Clostridium tyrobutyricum/crescimento & desenvolvimento , Hipersensibilidade a Ovo/sangue , Hipersensibilidade a Ovo/dietoterapia , Hipersensibilidade a Ovo/fisiopatologia , Feminino , Fermentação , Inspeção de Alimentos , Humanos , Imunoglobulina E/análise , Itália , Masculino , Muramidase/metabolismo , Índice de Gravidade de Doença , Fatores de Tempo
6.
Int J Immunopathol Pharmacol ; 23(1): 247-54, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20378010

RESUMO

In the present study we evaluated B-cell subsets and their functional development in 74 newborns from birth to 6 months of life. Moreover, we evaluated natural antibody production in vitro. The results documented a predominance of naive B-lymphocytes at all time-points evaluated, decreasing from birth to 6 months (p=0.009). The percentages of CD27+IgD+ and CD27+IgDneg memory B-cells were very low at birth and significantly increased only at 6 months (p=0.02 and p less than 0.001, respectively). We found a significant increase only in in vitro stimulated IgG production at 6 months as compared to birth (p less than 0.001). Moreover, a lower secretion of anti-Pn IgM antibodies up to 6 months of age, as compared to controls was observed. Our results underline that the susceptibility and severe course of infection in the neonate can be attributed, at least in part, to the lack of pre-existing immunological memory and competent adaptive immunity.


Assuntos
Subpopulações de Linfócitos B/imunologia , Recém-Nascido/imunologia , Adolescente , Anticorpos Antibacterianos/sangue , Cápsulas Bacterianas/imunologia , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulinas/sangue , Memória Imunológica , Lactente , Masculino , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/análise
7.
Artigo em Inglês | MEDLINE | ID: mdl-30723511

RESUMO

The aim of the present study is to evaluate the effects of 60-day artichoke leaf extract (ALE) supplementation (250mg, twice daily) on cytokines levels, natural killer cell (NK) response, and lipo-metabolic profile (HDL, LDL, and total-cholesterol, triglycerides (TG), ApoB, ApoA, lipid accumulation product (LAP), glucose, insulin, and homeostasis model assessment of insulin resistance (HOMA-IR)) in twenty adults (9/11 males/females, age=49.10 ± 13.74 years, and BMI=33.12 ± 5.14 kg/m2) with low HDL-C and mild hypercholesterolemia. Hierarchical generalized linear model, adjusted for sex, BMI, and age, has been used to evaluate pre-post treatment changes. A significant increase for HDL-C (ß=0.14, p=0.0008) and MCP-1 (ß=144.77, p=0.004) and a significant decrease for ApoB/ApoA (ß=-0.07, p=0.03), total-C/HDL-C ratio (ß=-0.58, p<0.001), and NK response at stimulus low (ß=0.43, p=0.04), medium (ß=0.40, p<0.001), and high (ß=0.42, p=0.001) have been found. These results support the benefits of ALE supplementation on metabolic profile.

8.
Pediatr Med Chir ; 30(4): 197-203, 2008.
Artigo em Italiano | MEDLINE | ID: mdl-19216203

RESUMO

Recent studies report that some probiotic strains are able to improve allergic diseases. For this reason, we would verify tolerability and efficacy of a industrial preparation of Lactobacillus paracasei (11,688; Proge Farm, Italy) and Lactobacillus salivarius (11,794; Proge Farm, Italy) and value their "in vitro" immunomodulatory effect. We know that, after birth, there's a persistence of Th2 immune response that predisposes to atopy, whereas commensal bacteria are able to induce a Th1 immune response that counter-balances the original response. The "in vivo" study was set up with the recruitment of 20 atopic pediatric patients treated 30 days with 2 doses of Fiorilac (Sharper, Italy), a preparation of the two strains in the proportion of 1:12. Only one patient referred significant improvements of atopic disease, 19 patients reported a good tolerability to the product and 3 patients had a regularization of intestinal function. Immunological tests showed an increase of Th1 immune response as in CD4+ lymphocytes percentage as of IL-12 and IL-10 cytokines production and a significant increase of natural killer (NK) activity, which predisposes to an active response to viral infections and neoplastic transformations.


Assuntos
Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/imunologia , Dermatite Perioral/tratamento farmacológico , Dermatite Perioral/imunologia , Lactobacillus , Ativação Linfocitária , Probióticos/administração & dosagem , Linfócitos T CD4-Positivos/imunologia , Criança , Dermatite Alérgica de Contato/tratamento farmacológico , Dermatite Alérgica de Contato/imunologia , Feminino , Humanos , Interleucina-10/imunologia , Interleucina-12/imunologia , Células Matadoras Naturais/imunologia , Masculino , Estudos Prospectivos , Rinite/tratamento farmacológico , Rinite/imunologia , Células Th1/imunologia , Resultado do Tratamento
9.
Mech Dev ; 69(1-2): 203-7, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9486542

RESUMO

The Drosophila Notch gene and its ligands, Delta and Serrate, are involved in cell fate determination in a variety of developing tissues. Recently, several Notch, Delta and Serrate homologues have been identified in vertebrates. We report here the cloning of the human and murine JAGGED2 (JAG2), a Serrate-like gene, and the analysis of its expression pattern during embryogenesis. Jag2 was found to be expressed as early as E9 in the surface ectoderm of the branchial arches and in the apical ectodermal ridge (AER) of the developing limb. At E12.5, Jag2 expression is upregulated in differentiated neurons of the central and peripheral nervous system and in the inner neuroblastic layer of the developing retina. Outside the nervous system, Jag2 is expressed in the developing vibrissae follicles, tooth buds, thymus, submandibular gland and stomach. Our findings suggest the involvement of Jagged2 in the development of the mammalian limb, branchial arches, central and peripheral nervous systems and several tissues whose development depends upon epithelial-mesenchymal interactions.


Assuntos
Proteínas de Transporte/genética , Ectoderma/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Membrana/metabolismo , Mesoderma/fisiologia , Proteínas/genética , Animais , Indução Embrionária , Epitélio/fisiologia , Extremidades/embriologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Proteína Jagged-2 , Camundongos , Dados de Sequência Molecular , Sistema Nervoso/embriologia , Proteínas/metabolismo , Receptores Notch , Homologia de Sequência de Aminoácidos
10.
Thromb Haemost ; 60(2): 145-7, 1988 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-3217914

RESUMO

Protein C (PC) activities measured by two thrombin-based assays have been compared with those obtained by two assays based on snake venom activation of plasma PC followed by measurement of both the amidolytic and anticoagulant activities of activated PC. This study indicates that snake venom assays gave results similar to those of the thrombin assays in 20 healthy subjects, in 16 patients with DIC and in 15 patients with congenital PC deficiency. There was, however, some degree of misclassification of normals and congenitally-deficient patients, with only the clotting snake venom assay resulting in no misclassifications. In 15 patients stabilized on warfarin treatment and in 17 with liver disease, the clotting snake venom assay gave significantly lower values than the other assays, so that it might prove to be more sensitive than the other assays to these defects.


Assuntos
Venenos de Crotalídeos/farmacologia , Proteína C/análise , Trombina/farmacologia , Humanos , Cirrose Hepática/sangue , Varfarina/uso terapêutico
11.
Thromb Haemost ; 55(1): 31-3, 1986 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-3754658

RESUMO

Low plasma levels of antithrombin III due to excessive urinary loss are thought to be the cause of thrombotic complications in patients with the nephrotic syndrome. To see whether protein C (PC), another antithrombotic protein, is also reduced in plasma by the same mechanism, plasma and urinary protein C were determined in 24 patients with nephrotic syndrome and no thrombotic complication, and compared to plasma and urinary antithrombin III. Twenty patients (83%) had high plasma levels of protein C activity (mean +/- SD 157 +/- 41 U/dl) and antigen (158 +/- 41). Even though measurable amounts of PC antigen were found in the urines of all but two patients the urinary loss of protein C relative to its plasma concentration was about 40 times lower than that of antithrombin III. High protein C might help to counteract hypercoagulability in nephrotic syndrome.


Assuntos
Glicoproteínas/sangue , Síndrome Nefrótica/sangue , Adolescente , Adulto , Idoso , Antígenos/análise , Antitrombina III/metabolismo , Antitrombina III/urina , Feminino , Glicoproteínas/imunologia , Glicoproteínas/urina , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome Nefrótica/imunologia , Síndrome Nefrótica/urina , Proteína C , Trombose/etiologia
12.
Thromb Haemost ; 62(2): 708-14, 1989 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-2530647

RESUMO

Four mouse hybridomas secreting monoclonal antibodies specific for human protein S (PS) have been generated. The antibodies, all of the IgG1 subclass, were designated S2, S3, S8, and S10. In a fluid phase radioimmunoassay, the binding of monoclonal antibodies to PS was about 30% greater in the presence of EDTA and totally inhibited in presence of Ca2+. Using the same technique, we performed displacement curves of 125I-labeled PS by purified PS, thrombin-cleaved PS, normal plasma, plasma from a patient on warfarin therapy, and plasma from a patient with no free PS and only PS bound to C4b-binding protein. The slopes of the curves show that the monoclonal antibodies reacted equally with all the tested forms of PS indicating that the antigenic site(s) to which the monoclonal antibodies are directed are present and exposed in free and bound PS, in thrombin-cleaved PS, and in the coumarin form of the protein. Each EDTA-dependent antibody, immobilized on Sepharose 4B-CNBr was used to purify PS from the barium citrate-absorbed, ammonium sulphate-soluble fraction of plasma. The fraction eluted from the immunoabsorbent with a buffer containing 4 mmol/l CaCl2 and analysed by SDS-PAGE, contained two bands, one migrating with conventionally purified PS and the other with purified C4b-binding protein. Homogeneous PS was obtained by chromatography of the barium citrate adsorbate on a DEAE-Sephadex column. The protein peak containing the bulk of PS was subsequently applied to the immunoadsorbent and eluted with 4 mmol/l CaCl2.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Anticorpos Monoclonais/imunologia , Glicoproteínas/imunologia , Animais , Anticorpos Monoclonais/biossíntese , Reações Antígeno-Anticorpo , Ligação Competitiva , Cálcio/sangue , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Glicoproteínas/isolamento & purificação , Humanos , Imunoensaio/métodos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteína C/isolamento & purificação , Conformação Proteica , Proteína S , Radioimunoensaio
13.
Thromb Haemost ; 62(2): 763-6, 1989 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-2530648

RESUMO

We describe a previously unreported defect of protein S characterized by low levels of cofactor activity for activated protein C contrasting with low normal levels of total and free protein S antigen. The distribution of protein S between the free form and the form complexed with the complement component C4b-binding protein was normal on two-dimensional immunoelectrophoresis. The proband developed juvenile deep-vein thrombosis while taking oral contraceptives. Her defect was transmitted in an autosomal dominant fashion from her asymptomatic mother. Other relatives carrying the same laboratory abnormality (mother, maternal uncle, two sisters and one brother) were also asymptomatic. We postulate that the defect is due to a dysfunctional protein S present in plasma in normal amounts and with normal proportions of the free and complexed forms of the protein.


PIP: A case of deep-vein thrombosis in a 23-year old woman 1 month after starting oral contraceptives is described, the 1st known incident of defective Protein S activity with normal levels of Protein S but defective APC cofactor. The woman had no known personal risk factors or family history of thromboembolism. She noticed pain and swelling of her right leg, and on admission to the Institute of Internal Medicine of the University of Milan, bilateral leg venography demonstrated occlusion of the right popliteal, femoral and iliac veins. She was treated with intravenous heparin for 10 days, and then warfarin. Protein S is a vitamin K-dependent plasma protein which binds to platelets and endothelial cells and functions as a cofactor for Protein C in the proteolytic cleavage of the activated forms of coagulation factors V and VIII. Persons with Protein S deficiency are at a high risk for thromboembolism. All coagulation laboratory screens were normal on repeated testing of the proband's plasma before initiating therapy, as well as her family members. In this patient total protein S antigen was low normal by EIA and ELISA. APC-cofactor was the only assay clearly abnormal, in the proband, her mother, siblings and maternal uncle; APC- cofactor activity was restored to normal by adding back pure Protein S.


Assuntos
Tromboflebite/genética , Adulto , Anticoncepcionais Orais/efeitos adversos , Ensaio de Imunoadsorção Enzimática , Feminino , Genes Dominantes , Glicoproteínas/genética , Heparina/uso terapêutico , Humanos , Imunoensaio , Imunoeletroforese Bidimensional , Masculino , Proteína C/metabolismo , Proteína S , Tromboflebite/tratamento farmacológico
14.
Thromb Haemost ; 78(5): 1343-6, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9408016

RESUMO

A recent study suggests that protein S deficiency is not a risk factor for venous thrombosis. Since this unexpected finding would have important clinical implications if confirmed, we performed a case-control study with the aim to determine the prevalence of protein S deficiency in patients with thrombosis and in healthy individuals taken from the general population and the relative risk of thrombosis in protein S-deficient patients. Free protein S concentration was measured in 327 consecutive patients with at least one venous thrombotic episode and in 317 age- and sex-matched control individuals. Different normal reference ranges were obtained and adopted for men and women. Protein S deficiency was found in 3.1% (95% CI: 1.5-5.2) of patients and in 1.3% of controls (95% CI: 0.3-2.8). Ten patients and 4 control subjects had protein S deficiency, which determined a relative risk of thrombosis (sex- and age-adjusted odds ratio) of 2.4 (95% CI: 0.8-7.9). When men and women were analyzed separately, the risk was 5.0 (95% CI: 0.6-43.6) and 1.6 (95% CI: 0.4-6.7) respectively. PS-deficient men had more thrombotic episodes than women and later in life. Multivariate analysis established that sex was an independent determinant of the number of episodes, as was age, while PS deficiency was not. However sex and PS deficiency status were both determinants of age at first thrombotic episode.


Assuntos
Deficiência de Proteína S/sangue , Tromboflebite/sangue , Tromboflebite/etiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Proteína S/análise , Deficiência de Proteína S/diagnóstico , Deficiência de Proteína S/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Tromboflebite/congênito
15.
Thromb Haemost ; 66(4): 420-5, 1991 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-1796390

RESUMO

Twenty-nine of 54 uremic patients had low levels of protein C measured as anticoagulant activity, contrasting with normal levels measured as amidolytic activity or antigenic concentration. We demonstrate that this discrepancy is due to the presence of a soluble plasma inhibitor that interferes specifically with the anticoagulant activity of activated protein C. The inhibitor does not interfere with other coagulation assays. It is resistant to diisopropylfluorophosphate, high temperatures and repeated freezing and thawing. It can be dissociated from protein C by anti-protein C antibodies or by dialysis in vitro and in vivo. It binds to positively charged resins and can be eluted with high salt concentrations without losing its inhibitory capacity. The inhibitory effect is correlated with plasma creatinine levels and fluctuates with time.


Assuntos
Falência Renal Crônica/sangue , Proteína C/antagonistas & inibidores , Uremia/sangue , Adulto , Idoso , Bário , Cromatografia em Gel , Feminino , Humanos , Falência Renal Crônica/complicações , Masculino , Pessoa de Meia-Idade , Tempo de Tromboplastina Parcial , Proteína C/isolamento & purificação , Proteína C/metabolismo , Uremia/etiologia
16.
Thromb Haemost ; 57(1): 44-8, 1987 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-3590079

RESUMO

Five functional assays and two immunoassays for protein C (PC) were evaluated in parallel for the same plasma samples collected from healthy subjects, patients with congenital and acquired PC deficiencies or patients with conditions associated with high PC levels. For 7 patients starting warfarin therapy and for 15 patients during stabilized warfarin therapy, there were significant between-assay differences. For these groups immunoassays gave higher values than most functional assays and the latter also gave varied results, probably depending on their respective capacity for recognizing a carboxylated PC. On the other hand, there were no significant between-assay differences nor discrepancies between PC activity and antigen levels for healthy subjects (n = 39), patients with congenital PC deficiency (n = 10), myocardial infarction (n = 25), chronic liver disease (n = 19), disseminated intravascular coagulation (n = 35), in the post-operative period (n = 20) or in women taking oral contraceptives (n = 20). This comparison of PC assays indicates that PC levels measured by different functional or immunological assays are very close in the majority of clinical conditions, but not for patients on oral anticoagulants.


Assuntos
Proteína C/análise , Testes de Coagulação Sanguínea/métodos , Feminino , Humanos , Imunoensaio/métodos , Masculino , Proteína C/genética , Proteína C/imunologia , Deficiência de Proteína C , Valores de Referência , Varfarina/uso terapêutico
17.
Thromb Res ; 60(1): 19-32, 1990 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-2148988

RESUMO

Protein S activity was measured as the degree of prolongation of a prothrombin time-based clotting assay in which diluted test sample, protein S-depleted plasma previously incubated with Protac to fully activate protein C, bovine thromboplastin and calcium ions are mixed. Assay specificity was first demonstrated by observing that the prolongation of the clotting time was dependent on protein S and was subsequently confirmed by testing plasma samples from patients with conditions known to affect protein S activity. High sensitivity, reproducibility (interassay coefficient of variation lower than 5%) and easy handling of samples and reagents make this assay suitable for screening of congenital and acquired protein S deficiency.


Assuntos
Análise Química do Sangue/métodos , Glicoproteínas/sangue , Tempo de Protrombina , Anticoagulantes/uso terapêutico , Feminino , Glicoproteínas/deficiência , Humanos , Cirrose Hepática/sangue , Masculino , Gravidez , Proteína C/metabolismo , Proteína S , Valores de Referência
18.
Eur J Gastroenterol Hepatol ; 9(5): 497-503, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9187884

RESUMO

OBJECTIVE: To define whether there is any relation between the iron status of patients with hepatitis C virus (HCV) chronic liver disease and their response to interferon therapy. DESIGN: To evaluate the long-term response to 1 year of interferon therapy with addition of phlebotomies after 3 months of treatment if at that time alanine aminotransferase (ALT) had not normalized in a group of patients with HCV-positive chronic liver disease whose iron status had been characterized. SETTING: A northern Italian hospital. PARTICIPANTS: Fifty-eight anti-HCV-positive patients (four HCV-RNA negative) with biopsy proven chronic hepatitis and no evidence of iron overload as indicated by normal transferrin saturation at the time of enrollment in the study. INTERVENTION: Three times a week intramuscular injection of alpha interferon 3 MU for 1 year with addition of phlebotomies (350 ml/week) till iron depletion if after 3 months of interferon therapy ALT had not normalized. RESULTS: A long-term response was observed in 19 of the 52 patients who completed the treatment, four HCV-RNA negative and 15 positive. The four RNA-negative and seven of the 15 RNA-positive long-term responders had been treated with interferon alone, and the other eight also with phlebotomies. At univariate analysis only HCV genotype, gamma-glutamyltranspeptidase and liver iron concentration were significantly associated with response whereas sinusoidal iron deposition was of borderline significance. No association was found with sex, age, duration of disease, histology, Knodell score, transferrin saturation %, serum ferritin, hepatocytic iron score, and portal iron score. HCV-RNA serum levels, measured in 29 patients, did not correlate with response. At multivariate analysis liver iron concentration was still significant and one unit reduction of liver iron concentration (natural logarithm transformed) was associated with 2.95 odds ratio of response. CONCLUSION: These results indicate that iron in the liver is more closely related to response to interferon than the other variables considered, including HCV characteristics.


Assuntos
Antivirais/uso terapêutico , Hepatite C/metabolismo , Interferon-alfa/uso terapêutico , Ferro/metabolismo , Adulto , Idoso , Alanina Transaminase/sangue , Antivirais/administração & dosagem , Doença Crônica , Ensaio de Imunoadsorção Enzimática , Feminino , Ferritinas/sangue , Seguimentos , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/patologia , Hepatite C/terapia , Anticorpos Anti-Hepatite C/análise , Humanos , Injeções Intramusculares , Interferon-alfa/administração & dosagem , Masculino , Pessoa de Meia-Idade , RNA Viral/análise , Estudos Retrospectivos , Transferrina/metabolismo , gama-Glutamiltransferase/metabolismo
19.
J Thromb Haemost ; 12(3): 329-36, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24354764

RESUMO

BACKGROUND: The formation of ADAMTS13-specific circulating immune complexes (CICs) may be a pathophysiologic mechanism in autoimmune thrombotic thrombocytopenic purpura (TTP), but has not been systematically investigated. OBJECTIVES: (a) To develop an assay for ADAMTS13-specific CICs; (b) to evaluate their prevalence in autoimmune TTP; and (c) to assess their association with ADAMTS13-related measurements and clinical features in autoimmune TTP patients. PATIENTS/METHODS: We developed and validated an ELISA method for ADAMTS13-specific CICs. ADAMTS13-specific CICs were searched for in 55 patients with autoimmune TTP from the Milan TTP Registry (URL:http://www.ttpdatabase.org/) and 28 controls. The associations between ADAMTS13-specific CIC levels and ADAMTS13 activity, antigen, anti-ADAMTS13 IgGs and acute TTP clinical features were assessed by multivariate linear regression. RESULTS: Intra- and inter-assay coefficients of variation of the new test were 5.3 and 9.6%. In 36 patients with severe ADAMTS13 deficiency and anti-ADAMTS13 autoantibodies, the prevalence of ADAMTS13-specific CICs was 47% (n = 17; 95% confidence interval [CI], 32-63%). ADAMTS13-specific CICs were detected also in seven of 19 (37%; 95% CI, 19-59%) patients with reduced ADAMTS13 activity, but apparently negative anti-ADAMTS13 autoantibodies. ADAMTS13-specific CICs were not associated with ADAMTS13 activity, antigen or anti-ADAMTS13 IgGs. In patients with acute TTP, increasing levels of ADAMTS13-specific CICs were associated with a higher number of plasma-exchange procedures required to attain remission (per 0.1 increase in normalized OD values, beta, 2.9; 95% CI, -0.7 to 6.5). CONCLUSIONS: Approximately one to two-thirds of patients with autoimmune TTP display ADAMTS13-specific CICs. A thorough investigation of the prognostic relevance of ADAMTS13-specific CIC levels in autoimmune TTP is warranted.


Assuntos
Proteínas ADAM/sangue , Complexo Antígeno-Anticorpo/sangue , Doenças Autoimunes/sangue , Púrpura Trombocitopênica Trombótica/sangue , Proteínas ADAM/imunologia , Proteína ADAMTS13 , Adulto , Doenças Autoimunes/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Prognóstico , Sistema de Registros , Reprodutibilidade dos Testes , Fator de von Willebrand/metabolismo
20.
Thromb Haemost ; 112(2): 297-303, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24740645

RESUMO

Collagen-binding activity (CBA) and FRETS-VWF73 assays are widely adopted methods for the measurement of the plasmatic activity of ADAMTS13, the von Willebrand factor (VWF) cleaving-protease. Accurately assessing the severe deficiency of ADAMTS13 is important in the management of thrombotic thrombocytopenic purpura (TTP). However, non-concordant results between the two assays have been reported in a small but relevant percentage of TTP cases. We investigated whether CBA or FRETS-VWF73 assay reflects ADAMTS13 proteolytic activity in acquired TTP patients with non-concordant measurements. Twenty plasma samples with non-concordant ADAMTS13 activity results, <10% using FRETS-VWF73 and ≥20% using CBA, and 11 samples with concordant results, <10% using either FRETS-VWF73 and CBA assays, were analysed. FRETS-VWF73 was performed in the presence of 1.5 M urea. ADAMTS13 activities were also measured under flow conditions and the VWF multimer pattern was defined in order to verify the presence of ultra-large VWF due to ADAMTS13 deficiency. In FRETS-VWF73 assay with 1.5 M urea, ADAMTS13 activity significantly increased in roughly 50% of the samples with non-concordant results, whereas it remained undetectable in all samples with concordant measurements. Under flow conditions, all tested samples showed reduced ADAMTS13 activity. Finally, samples with non-concordant results showed a ratio of high molecular weight VWF multimers higher than normal. Our results support the use of FRETS-VWF73 over CBA assay for the assessment of ADAMTS13 severe deficiency and indicate urea as one cause of the observed differences.


Assuntos
Proteínas ADAM/deficiência , Colágeno/metabolismo , Transferência Ressonante de Energia de Fluorescência , Púrpura Trombocitopênica Trombótica/diagnóstico , Fator de von Willebrand/metabolismo , Proteína ADAMTS13 , Humanos , Valor Preditivo dos Testes , Ligação Proteica , Desnaturação Proteica , Proteólise , Púrpura Trombocitopênica Trombótica/sangue , Púrpura Trombocitopênica Trombótica/enzimologia , Sistema de Registros , Reprodutibilidade dos Testes , Ureia/química
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