RESUMO
BACKGROUND AND PURPOSE: Ataxia-telangiectasia (A-T) is a rare neurodegenerative disease, due to A-T mutated (ATM) gene mutations, which typically presents with signs of progressive neurological dysfunction, cerebellar ataxia and uncoordinated movements. A-T severely affects patients' quality of life. Successful treatment options are still not available. The aim of this multicenter study, performed with a blind evaluation procedure, was to define the minimal effective dosage of oral betamethasone, thus preventing the occurrence of side effects. METHODS: Nine A-T patients were enrolled to receive betamethasone at increasing dosages of 0.001, 0.005 and 0.01 mg/kg/day. Neurological assessment and the evaluation of quality of life were performed through the Scale for the Assessment and Rating of Ataxia and the Italian version of the Childhood Health Assessment Questionnaire (CHAQ) at each time-point. The drug safety profile was evaluated. Patients were categorized as responders, partial responders and non-responders. RESULTS: Four of nine patients had a benefit at a dose of 0.005 mg/kg/day of oral betamethasone. Using the higher dosage, only one additional patient had a positive response. Conversely, a daily dose of 0.001 mg/kg was ineffective. A correlation between the serum adrenocorticotropic hormone levels and the clinical response was observed. Five of 30 CHAQ items improved in four patients. CONCLUSIONS: These data suggest that a short-term betamethasone oral treatment, at a daily dosage of 0.005 mg/kg, is effective in some patients. Pre-existing risk factors for side effects should be taken into account before therapy.
Assuntos
Ataxia Telangiectasia/tratamento farmacológico , Betametasona/administração & dosagem , Glucocorticoides/administração & dosagem , Adolescente , Betametasona/uso terapêutico , Criança , Pré-Escolar , Relação Dose-Resposta a Droga , Feminino , Glucocorticoides/uso terapêutico , Humanos , Masculino , Fenótipo , Qualidade de Vida , Resultado do Tratamento , Adulto JovemRESUMO
Kawasaki disease (KD) is a pediatric acute multisystemic vasculitis complicated by development of coronary artery lesions. The breakthrough theory on KD etiopathogenesis points to pathogens/environmental factors triggered by northeastern wind coming from China. Natural Killer cells and T lymphocytes express the inhibitory/activating Killer Immunoglobulin-like Receptors (KIR) to elicit an immune response against pathogens by binding to human leukocyte antigens (HLA) class I epitopes. We first report on the role of KIR/HLA genetic epistasis in a sample of 100 Italian KD children. We genotyped KIR, HLA-A, HLA-B and HLA-C polymorphisms, and compared KD data with those from 270 Italian healthy donors. The HLA-A*11 ligand for KIR2DS2/2DS4/3DL2 was a KD susceptibility marker by itself (odds ratio (OR)=3.85, confidence interval (CI)=1.55-9.53, P=0.004). Although no epistasis between HLA-A*11 and KIR2DS2/S4 emerged, HLA-A*11 also engages KIR3DL2, a framework gene encoding for a pathogen sensor of CpG-oligodeoxynucleotides (CpG-ODN), and KD blood mononuclear cells are actually prone to pathogen CpG-ODN activation in the acute phase. Moreover, carriers of KIR2DS2/HLA-C1 and KIR2DL2/HLA-C1 were more frequent among KD, in keeping with data demonstrating the involvement of these HLA/KIR couples in autoimmune endothelial damage. The highest KD risk factor was observed among carriers of KIR2DL2 and two or more HLA ligands (OR=10.24, CI=1.87-56.28; P=0.007).
Assuntos
Antígenos HLA/genética , Antígenos HLA/imunologia , Síndrome de Linfonodos Mucocutâneos/genética , Síndrome de Linfonodos Mucocutâneos/imunologia , Receptores KIR/genética , Receptores KIR/imunologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Suscetibilidade a Doenças/imunologia , Epistasia Genética , Feminino , Frequência do Gene , Antígeno HLA-A11/genética , Antígenos HLA-B/genética , Antígenos HLA-C/genética , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Imunoglobulinas/genética , Imunoglobulinas/imunologia , Masculino , Polimorfismo GenéticoRESUMO
OBJECTIVES: To study the health-related quality of life (HRQOL) in severe cryoglobulinaemic vasculitis (CV) associated with hepatitis C virus infection (HCV) and to describe the effect of rituximab on HRQOL. METHODS: HRQOL was evaluated with the Medical Outcomes Study Short Form 36 (SF-36). Health Survey questionnaire was submitted to 15 patients with severe CV. SF-36 questionnaire was evaluated at baseline and after rituximab. Physical Health Composite Summary (PCS) and Mental Health Composite Summary (MCS) scores were calculated according to standard protocols, and normalised to healthy controls. SF-36 summary scores were compared with those of HCV positive patients without CV, and other vasculitis published in the literature. European Quality of Life-5 dimensions (EQ5D) scores were also derived. RESULTS: Physical and mental domain scores were all reduced if compared with those of the healthy population, with physical domains being greatly affected. HRQOL of CV was comparable with HRQOL reported for the other small vessel vasculitis. The development of CV in HCV positive patients worsened PCS rather than MCS score. Birmingham Vasculitis Activity Score (BVAS) did not correlate with HRQOL, while the presence of peripheral neuropathy was associated with a worse HRQOL. Early rituximab treatment improved both PCS and MCS scores, with long-term effects. CONCLUSIONS: PCS rather than MCS was affected in HCV positive patients when CV is present. Rituximab improved both physical and mental domains, thus supporting its use before antiviral therapy in severe HCV-related CV. The cost/benefits ratio of a sequential therapy may be supported.
Assuntos
Anticorpos Monoclonais Murinos/uso terapêutico , Linfócitos B/efeitos dos fármacos , Crioglobulinemia/tratamento farmacológico , Nível de Saúde , Fatores Imunológicos/uso terapêutico , Depleção Linfocítica/métodos , Qualidade de Vida , Vasculite/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais Murinos/economia , Linfócitos B/imunologia , Análise Custo-Benefício , Crioglobulinemia/sangue , Crioglobulinemia/economia , Crioglobulinemia/imunologia , Crioglobulinemia/fisiopatologia , Crioglobulinemia/psicologia , Custos de Medicamentos , Feminino , Hepatite C/complicações , Hepatite C/imunologia , Hepatite C/virologia , Humanos , Fatores Imunológicos/economia , Depleção Linfocítica/economia , Masculino , Saúde Mental , Pessoa de Meia-Idade , Anos de Vida Ajustados por Qualidade de Vida , Rituximab , Índice de Gravidade de Doença , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento , Vasculite/sangue , Vasculite/economia , Vasculite/imunologia , Vasculite/fisiopatologia , Vasculite/psicologiaRESUMO
OBJECTIVE: To conduct a long-term, prospective, randomized controlled trial evaluating rituximab (RTX) therapy for severe mixed cryoglobulinemia or cryoglobulinemic vasculitis (CV). METHODS: Fifty-nine patients with CV and related skin ulcers, active glomerulonephritis, or refractory peripheral neuropathy were enrolled. In CV patients who also had hepatitis C virus (HCV) infection, treatment of the HCV infection with antiviral agents had previously failed or was not indicated. Patients were randomized to the non-RTX group (to receive conventional treatment, consisting of 1 of the following 3: glucocorticoids; azathioprine or cyclophosphamide; or plasmapheresis) or the RTX group (to receive 2 infusions of 1 gm each, with a lowering of the glucocorticoid dosage when possible, and with a second course of RTX at relapse). Patients in the non-RTX group who did not respond to treatment could be switched to the RTX group. Study duration was 24 months. RESULTS: Survival of treatment at 12 months (i.e., the proportion of patients who continued taking their initial therapy), the primary end point, was statistically higher in the RTX group (64.3% versus 3.5% [P < 0.0001]), as well as at 3 months (92.9% versus 13.8% [P < 0.0001]), 6 months (71.4% versus 3.5% [P < 0.0001]), and 24 months (60.7% versus 3.5% [P < 0.0001]). The Birmingham Vasculitis Activity Score decreased only after treatment with RTX (from a mean ± SD of 11.9 ± 5.4 at baseline to 7.1 ± 5.7 at month 2; P < 0.001) up to month 24 (4.4 ± 4.6; P < 0.0001). RTX appeared to be superior therapy for all 3 target organ manifestations, and it was as effective as conventional therapy. The median duration of response to RTX was 18 months. Overall, RTX treatment was well tolerated. CONCLUSION: RTX monotherapy represents a very good option for severe CV and can be maintained over the long term in most patients.
Assuntos
Anticorpos Monoclonais Murinos/uso terapêutico , Crioglobulinemia/terapia , Fatores Imunológicos/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antivirais/uso terapêutico , Azatioprina/uso terapêutico , Terapia Combinada , Crioglobulinemia/complicações , Crioglobulinemia/patologia , Ciclofosfamida/uso terapêutico , Farmacorresistência Viral/efeitos dos fármacos , Substituição de Medicamentos , Quimioterapia Combinada , Feminino , Glucocorticoides/uso terapêutico , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Plasmaferese , Indução de Remissão , Rituximab , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto JovemRESUMO
Primary immunodeficiencies (PIDs) are rare diseases characterized by an increased susceptibility to infections. Early diagnosis and appropriate treatment are critical for reducing morbidity and mortality. Based on available data, the efficacy of antibiotic administration for the prophylaxis of infections remains uncertain, and recommendations supporting this practice are poor. The use of antimicrobial prophylaxis is mainly based on single institution-specific experience without controlled measurements of patient safety and quality health outcomes. To address this issue an Italian Network on Primary Immunodeficiencies (IPINet) has been set up in 1999 within the Italian Association of Pediatric Hematology and Oncology (AIEOP) to increase the awareness of these disorders among physicians. Further, diagnostic and treatment guideline recommendations have been established to standardize the best clinical assistance to all patients, including antibiotic prophylaxis, and for a national epidemiologic monitoring of PIDs. The aim of this review is not only to give a scientific update on the use of antimicrobial prophylaxis in selected congenital immunological disorders but also to draw a picture of this practice in the context of the Italian Primary Immunodeficiency Network (IPINet). Controlled multicenter studies are necessary to establish if, when and how you should start an efficacious antimicrobial prophylaxis.
Assuntos
Antibioticoprofilaxia , Síndromes de Imunodeficiência/complicações , Imunodeficiência de Variável Comum/complicações , Síndrome de DiGeorge/complicações , Doença Granulomatosa Crônica/complicações , Humanos , Deficiência de IgA/complicações , Doenças por Imunodeficiência Combinada Ligada ao Cromossomo X/complicaçõesRESUMO
BACKGROUND: To develop preliminary classification criteria for the cryoglobulinaemic syndrome or cryoglobulinaemic vasculitis (CV). METHODS: Study part I developed a questionnaire for CV to be included in the formal, second part (study part II). Positivity of serum cryoglobulins was defined by experts as an essential condition for CV classification. In study part II, a core set of classification items (questionnaire, clinical and laboratory items, as agreed) was tested in three groups of patients and controls-that is, group A (new patients with the CV), group B (controls with serum cryoglobulins but lacking CV) and group C (controls without serum cryoglobulins but with features which can be observed in CV). RESULTS: In study part I (188 cases, 284 controls), a positive response to at least two of three selected questions showed a sensitivity of 81.9% and a specificity of 83.5% for CV. This questionnaire was employed and validated in study part II, which included 272 patients in group A and 228 controls in group B. The final classification criteria for CV, by pooling data from group A and group B, required the positivity of questionnaire plus clinical, questionnaire plus laboratory, or clinical plus laboratory items, or all the three, providing a sensitivity of 88.5% and a specificity of 93.6% for CV. By comparing data in group A versus group C (425 controls), the same classification criteria showed a sensitivity 88.5% and a specificity 97.0% for CV. CONCLUSION: Classification criteria for CV were developed, and now need validation.
Assuntos
Crioglobulinemia/classificação , Vasculite/classificação , Adulto , Idoso , Crioglobulinemia/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Inquéritos e Questionários , Síndrome , Vasculite/etiologiaRESUMO
A multi-residual method is described for the simultaneous determination of 23 personal care products (PCPs), which display a wide range of physicochemical properties, present at trace levels in water samples. A one-step procedure was developed based on solid-phase microextraction (SPME) coupled with GC-MS analysis. A chemometric approach consisting of an experimental design (design of experiments) was applied to systematically investigate how four operating parameters--extraction temperature and time and desorption temperature and time--affect extraction recovery of PCPs in water. The optimum SPME procedure operating conditions, those yielding the highest extraction recovery for all the compounds, were determined; they correspond to an extraction time of 90 min and temperature of 80 °C and a desorption time of 11 min and temperature of 260 °C. Under these optimized conditions, the SPME procedure shows good analytical performance characterized by high reproducibility (RSD% intra-day accuracy varying in the 0.01-1.3% range) as well as good linearity and low detection limits (LODs lower than 2 ppb for most of the investigated PCPs).
Assuntos
Cosméticos/isolamento & purificação , Microextração em Fase Sólida/métodos , Poluentes Químicos da Água/isolamento & purificação , Cosméticos/análise , Cromatografia Gasosa-Espectrometria de Massas , Poluentes Químicos da Água/análiseRESUMO
Dominant-negative mutations in STAT-3 have recently been found in the majority of patients with sporadic or autosomal-dominant hyper IgE syndrome (HIES). Since STAT-3 plays a role in B cell development and differentiation, we analyzed memory B cells in 20 patients with HIES, 17 of which had STAT-3 mutations. All but four patients had reduced non-switched and/or class-switched memory B cells. No reduction in these B cell populations was found in 16 atopic dermatitis patients with IgE levels above 1000 KU/L. There was no correlation between the reduction of memory B cells and the ability to produce specific antibodies. Moreover, there was no correlation between the percentage of memory B cells and the infection history. Analysis of memory B cells can be useful in distinguishing patients with suspected HIES from patients with atopic disease, but probably fails to identify patients who are at high risk of infection.
Assuntos
Linfócitos B/imunologia , Memória Imunológica/imunologia , Síndrome de Job/imunologia , Adolescente , Adulto , Anticorpos Antivirais/sangue , Formação de Anticorpos , Linfócitos B/patologia , Criança , Estudos de Coortes , DNA/química , DNA/genética , Dermatite Atópica/genética , Dermatite Atópica/imunologia , Dermatite Atópica/patologia , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Genótipo , Humanos , Imunoglobulina E/imunologia , Imunoglobulina E/metabolismo , Memória Imunológica/genética , Síndrome de Job/genética , Síndrome de Job/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/imunologia , Adulto JovemRESUMO
Transient hypogammaglobulinemia of infancy (THI) is a heterogeneous disorder characterized by reduced serum IgG levels in early infancy. A putative diagnosis is initially made after exclusion of other causes of hypogammaglobulinemia while a definitive diagnosis of THI can only be made a posteriori in patients with normalization of IgG levels. The aim of this study is to characterize clinical and immunological features of children with an initial diagnosis of THI in correlation to natural outcome, and to assess predictive laboratory parameters of clinical evolution for this disorder. We prospectively analysed clinical and immunological characteristics of 77 THI children at initial diagnosis and of 57 patients at follow-up. Memory B cell subsets and in vitro immunoglobulin production were evaluated. Seventy patients (91 percent) showed clinical symptoms. Patients suffered from infections (91 percent), allergies (47 percent) and autoimmune disease (4 percent). During follow-up 41/57 children (72 percent) normalized IgG values, mostly within 24 months of age (p less than 0.001), allowing the diagnosis of THI. The 16 children who did not normalize their IgG levels showed a higher frequency of severe infections and autoimmune disease (p less than 0.01). Moreover, they expressed a reduced frequency of IgM and switched memory B cells (p less than 0.01) and an inability to produce IgG in vitro (p less than 0.02). We conclude that most patients with an initial diagnosis of THI spontaneously recover within 24 months of age and have a benign clinical course, while a subgroup of children with undefined hypogammaglobulinemia share a clinical and immunological profile with other primary immunodeficiencies. Early recognition of children with hypogammaglobulinemia during infancy who are likely to suffer from permanent immunodeficiencies later in life would allow prompt and appropriate laboratory and clinical interventions.
Assuntos
Agamaglobulinemia/epidemiologia , Síndromes de Imunodeficiência/epidemiologia , Envelhecimento/imunologia , Linfócitos B/imunologia , Pré-Escolar , Progressão da Doença , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Imunoglobulinas/biossíntese , Memória Imunológica/imunologia , Lactente , Itália/epidemiologia , Masculino , Estudos Prospectivos , Resultado do TratamentoRESUMO
The immobilization of proteins on carbon nanotubes (CNTs) has been widely reported mainly for the preparation of sensors while the conjugation of enzymes for therapeutic purposes has scarcely been considered. Herein we report, to the best of our knowledge, the first example of intracellular delivery of a therapeutic enzyme by means of CNTs, retaining its activity. Mucopolysaccharidosis I is a rare genetic disease characterized by the deficiency or absence of the activity of the α-l-iduronidase (IDUA) enzyme. We evaluated the capacity of the recombinant form of the human IDUA enzyme, laronidase (Aldurazyme®), conjugated with CNTs to be internalized by fibroblasts from subjects affected with Mucopolysaccharidosis type I and the capacity of the enzyme to retain its activity after internalization. The enzyme was successfully delivered into the lysosomal space and the enzymatic activity of the conjugate was preserved after internalization up to 48 hours. This paves the way towards the use of such a kind of construct for therapeutic applications.
Assuntos
Portadores de Fármacos , Iduronidase/administração & dosagem , Mucopolissacaridose I/tratamento farmacológico , Nanotubos de Carbono , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Humanos , Proteínas Recombinantes/administração & dosagem , Pele/citologiaRESUMO
Circulating T cells from four patients with the hyper-IgE syndrome were found to produce significantly lower concentrations of interferon-gamma (IFN-gamma) in response to stimulation with phytohemagglutinin (PHA) than did T cells from eight age-matched healthy controls, three patients with atopic dermatitis and one patient with chronic granulomatous disease. A clonal analysis revealed that patients with hyper-IgE syndrome had markedly lower proportions of circulating T cells able to produce IFN-gamma and tumor necrosis factor-alpha (TNF-alpha) in comparison with controls. In contrast, the proportions of peripheral blood T cells able to produce IL-4 or IL-2 were not significantly different in patients and controls. All the four patients with hyper-IgE syndrome showed high proportions of circulating CD4+ helper T cells able to induce IgE synthesis in allogeneic B cells, as well. Such an activity for IgE synthesis appeared to be positively correlated with IL-4 production by T cells and inversely related to the ability of the same T cells to produce IFN-gamma. Since IFN-gamma exerts an inhibitory effect on the synthesis of IgE and both IFN-gamma and TNF-alpha play an important role in inflammatory reactions, we suggest that the defective production of IFN-gamma may be responsible for hyperproduction of IgE and the combined defect of IFN-gamma and TNF-alpha may contribute to the undue susceptibility to infections seen in patients with hyper-IgE syndrome.
Assuntos
Hipergamaglobulinemia/sangue , Imunoglobulina E , Interferon gama/biossíntese , Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Adolescente , Adulto , Criança , Feminino , Humanos , Imunoglobulina E/biossíntese , Contagem de Leucócitos , Fito-Hemaglutininas/farmacologia , Síndrome , Linfócitos T/patologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/patologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologiaRESUMO
This work describes a GC-MS method for enantioselective separation of amino acids. The method is based on a derivatization reaction which employs a mixture of alkyl chloroformate-alcohol-pyridine, as reagents to obtain the N(O,S)-alkyl alkoxy carbonyl esters of amino acids. Various reaction parameters are investigated and optimized to achieve a reproducible derivatization procedure suitable for separation of amino acid enantiomers on Chirasil-L-Val chiral stationary phase. In particular, the following topics are investigated for 20 proteinogenic amino acids: (i) the proper reagent and reaction conditions to obtain the highest derivative yield; (ii) the amino acid reactivity and the MS properties of the obtained derivatives; (iii) the linearity and sensitivity of the analytical method; (iv) the retention behavior of the derivatives and their enantiomeric separation on the Chirasil-L-Val chiral stationary phase. By combining the resolution power of the Chirasil-L-Val column and the high selectivity of the SIM MS detection mode, the described procedure enables the enantiomeric separation and quantification of 16 enantiomeric pairs of amino acids. The procedure is simple and fast and reproducible. It displays a wide linearity range at ppb detection limits for quantitative determinations: these properties make this derivatization method a suitable candidate for amino acid GC-MS analysis on board of the spacecrafts in space exploration missions of solar system body environments.
Assuntos
Aminoácidos/química , Formiatos/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Aminoácidos/análise , Estrutura Molecular , Reprodutibilidade dos Testes , EstereoisomerismoRESUMO
OBJECTIVE: The aim of this study was to investigate potential risk factors for Sjögren's syndrome (SS) by means of a multi-centre case-control study, focusing in particular on familial and environmental risk factors. 140 female SS patients and 109 female controls with orthopaedic problems were consecutively enrolled in seven university hospitals in Italy. METHODS: Information regarding the patient's lifestyle, her medical, menstrual and pregnancy history, and any family history of autoimmune diseases (AD) was obtained through a detailed structured questionnaire. The odds ratio (OR) and 95% confidence interval (95%CI) were calculated using unconditional logistic regression, adjusting for age and family size. The probability of first-degree relatives developing an autoimmune disease was also investigated. RESULTS: A positive family history of AD was significantly associated with SS. Subjects with a first-degree relative (FDR) with AD showed a seven-fold increase in the risk for SS compared to controls (OR=7.4, 95%CI 2.8-20.1); the strength of this association increased with the number of relatives affected. Similarly, the FDR of SS patients had a higher risk of AD in comparison to subjects without FDR affected by SS. Women with one or more pregnancies had an increased risk of SS (OR=2.1, 95%CI 1.0-4.3). CONCLUSION: This study suggests that a family history of AD is associated with SS.
Assuntos
História Reprodutiva , Síndrome de Sjogren/genética , Adulto , Idoso , Doenças Autoimunes/etiologia , Estudos de Casos e Controles , Feminino , Inquéritos Epidemiológicos , Humanos , Estilo de Vida , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Linhagem , Fatores de Risco , Síndrome de Sjogren/epidemiologia , FumarRESUMO
An interlaboratory comparison was performed to evaluate the analytical methods for quantification of anhydrosugars - levoglucosan, mannosan, galactosan - and biosugars - arabitol, glucose and mannitol - in atmospheric aerosol. The performance of 10 laboratories in Italy currently involved in such analyses was investigated on twenty-six PM (particulate matter) ambient filters, three synthetic PM filters and three aqueous standard solutions. An acceptable interlaboratory variability was found, determined as the mean relative standard deviation (RSD%) of the results from the participating laboratories, with the mean RSD% values ranging from 25% to 46% and decreasing with increasing sugar concentration. The investigated methods show good accuracy, evaluated as the percentage error (ε%) related to mean values, since method biases ranged within ±20% for most of the analytes measured in the different laboratories. The detailed investigation (ANOVA analysis at p < 0.05) of the contribution of each laboratory to the total variability and the measurement accuracy shows that comparable results are generated by the different methods, despite the great diversity in terms of extraction conditions, chromatographic separation - more recent LC (liquid chromatography) and EC (exchange chromatography) methods compared to more widespread GC (gas chromatography) - and detection systems, namely PAD (pulsed amperometric detection) or mass spectrometry.
Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Carboidratos/análise , Monitoramento Ambiental/métodos , Espectrometria de Massas/métodos , Variações Dependentes do Observador , Cromatografia Líquida , Galactose/análogos & derivados , Galactose/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Glucose/análogos & derivados , Glucose/análise , Itália , Manose/análogos & derivados , Manose/análise , Material Particulado/análise , Álcoois Açúcares/análiseRESUMO
Gas chromatography-mass spectrometry (GC-MS) will be used in future space exploration missions, in order to seek organic molecules at the surface of Mars, and especially potential chemical indicators of life. Carboxylic acids are among the most expected organic species at the surface of Mars, and they could be numerous in the analysed samples. For this reason, a chemometric method was applied to support the interpretation of chromatograms of carboxylic acid mixtures. The method is based on AutoCovariance Function (ACVF) in order to extract information on the sample--number and chemical structure of the components--and on separation performance. The procedure was applied to standard samples containing targeted compounds which are among the most expected to be present in the Martian soil: n-alkanoic and benzene dicarboxylic acids. ACVF was computed on the obtained chromatograms and plotted versus retention time: peaks of the ACVF plot can be related to specific molecular structures and are diagnostic for chemical identification of compounds.
Assuntos
Exobiologia , Cromatografia Gasosa-Espectrometria de Massas/métodos , Marte , Solo/análiseRESUMO
PURPOSE: The effects of a low-antigen-content diet (LAC diet) versus a standard normocaloric diet on the signs and symptoms of mixed cryoglobulinemia (MC) were compared in a crossover randomized study. PATIENTS AND METHODS: The study consisted of 24 outpatients with MC, and was carried out in a 48-week period. After 18 weeks of either the LAC or the placebo diet, patients returned to a totally unrestricted diet for 12 weeks (washout period) and crossed over to the second half of the study for the other 18 weeks. RESULTS: After three weeks of the restricted LAC diet, the cryocrit decreased from 3.5 +/- 3.4% (mean +/- SD) to 2.3 +/- 2.0% (p less than 0.01), and the circulating immune complex levels decreased from 48 +/- 30% to 39 +/- 34% (p less than 0.01). At the same time, the purpura score (p less than 0.05), glutamic pyruvic transaminase level (p less than 0.01), and gamma glutamyl transferase level (p less than 0.001) significantly improved. Splenic reticuloendothelial function, measured as the half-life of heat-damaged autologous red cells, decreased from 41 +/- 21 minutes to 21 +/- 10 minutes (p less than 0.005). In contrast, no significant parallel clinical, biochemical, and immunologic changes occurred in the same patients during the placebo (standard normocaloric) diet. CONCLUSION: These data show that an LAC diet decreases the amount of circulating immune complexes in MC and can modify certain signs and symptoms of the disease. These effects of the LAC diet may be explained by postulating a functional restoration of the mononuclear phagocytic system.
Assuntos
Crioglobulinemia/dietoterapia , Adulto , Idoso , Antígenos/imunologia , Crioglobulinemia/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Distribuição AleatóriaRESUMO
A quantitative study of the relationship between structure and receptor binding affinity of a series of 16 beta-carbolines showed the influence of lipophilic character and hydrogen bonding capability of substituents in position 3. Some data taken from the literature enabled us to add some evidence about the influence of planarity of ring C and bulky substituents in position 1 in determining the receptor binding affinity.
Assuntos
Carbolinas/metabolismo , Receptores de GABA-A/metabolismo , Animais , Ligação de Hidrogênio , Técnicas In Vitro , Ratos , Solubilidade , Relação Estrutura-AtividadeRESUMO
A commercial latex agglutination (LA) kit (Wellcogen, Wellcome Diagnostics) used to detect bacterial polysaccharide antigens (Haemophilus influenzae type b and Streptococcus pneumoniae) was compared with a modified counterimmunoelectrophoresis technique and blood culture for etiologic diagnosis of presumptive bacterial pneumonia requiring hospitalization in 60 infants and children. Serum, urine and either sputum or nasopharyngeal secretions were collected during the first 5 days of therapy for antigen detection. Blood culture was positive in 6 of 52 (11.5%) of cases. Antigens were detected by counterimmunoelectrophoresis and/or LA in 13 of 60 (21.7%) serum samples, 2 of 16 (12.5%) unconcentrated urine samples, 19 of 42 (45.2%) urine samples concentrated 25-fold and 21 of 45 (46.7%) sputum or nasopharyngeal secretions. Antibiotic treatment for 5 days did not affect the antigen detection rate. Counter-immunoelectrophoresis was more sensitive than LA in serum and urine but not in sputum. However, because false positive reactions were frequently obtained with LA on nasopharyngeal secretions of an age-matched control group, this test appears unreliable.
Assuntos
Infecções Bacterianas/diagnóstico , Contraimunoeletroforese , Haemophilus influenzae/isolamento & purificação , Imunoeletroforese , Testes de Fixação do Látex , Pneumonia/diagnóstico , Streptococcus pneumoniae/isolamento & purificação , Adolescente , Criança , Pré-Escolar , Diagnóstico Diferencial , Infecções por Haemophilus/diagnóstico , Humanos , Lactente , Infecções Estreptocócicas/diagnósticoRESUMO
Serum total lipids, lipoprotein cholesterol, apolipoprotein A (Apo A), and liver function tests have been investigated in patients with acute viral hepatitis and chronic liver disease. Hypertriglyceridaemia, absence of alpha and pre beta bands on the lipoprotein electrophoresis pattern, low level of Apo A, and presence of abnormal lipoproteins (beta-VLDL and beta2-LP) were observed in the early phase of acute hepatitis. A positive correlation was found between Apo A and high-density lipoprotein cholesterol, and a negative one between Apo A and triglyceride, bile acids, total bilirubin, and serum alanine aminotransferase. Lipoprotein abnormalities found in the early phase of acute hepatitis are probably due to low lecithin-cholesterol acyltransferase activity. The reappearance of alpha lipoprotein and the increase of Apo A are sensitive indices of improvement of liver function. In chronic liver disease low levels of cholesterol and Apo A indicate the severity of liver cell injury.
Assuntos
Hepatite Viral Humana/sangue , Lipídeos/sangue , Hepatopatias/sangue , Apolipoproteínas/sangue , Colesterol/sangue , Doença Crônica , Eletroforese em Gel de Ágar , Feminino , Humanos , Imunoeletroforese Bidimensional , Lipoproteínas/sangue , Masculino , Triglicerídeos/sangueRESUMO
In a multi-centre retrospective study, we compared clinical and laboratory data in 913 patients with cryoglobulinaemias, divided as: (i) essential cryoglobulinaemias; (ii) cryoglobulinaemias secondary to connective tissue diseases (CTD), lymphoproliferative or other haematological diseases (LPD), chronic liver diseases (CLD), and 'other diseases'. Purpura was the commonest presenting feature in all groups and was more common in essential cryoglobulinaemias (p < 0.0001). Meltzer's triad (purpura, arthralgia, weakness) was less frequent, but similarly distributed. Renal involvement was randomly distributed. Neurological impairment was less frequent in cryoglobulinaemias secondary to CLD (p < 0.002). Raynaud's phenomenon, arthritis and sicca syndrome were more frequent in cryoglobulinaemias secondary to CTD. Essential cryoglobulinaemias had a significantly higher percentage of serum complement C4 < 8 mg/dl (p < 0.004), of detectable rheumatoid factor activity (p < 0.0002), and of type II cryoglobulins (p < 0.0001). Liver involvement was evident at presentation in 32.6% of essential cryoglobulinaemias, 27.1% of cryoglobulinaemias secondary to LPD and 12.2% of cryoglobulinaemias secondary to CTD. Antibodies to hepatitis B surface (HBsAg) and core (HBc) antigens were more frequent in cryoglobulinaemias secondary to CLD; anti-HBs antibodies were randomly distributed. Antibodies to hepatitis C (HCV) were tested for in 224 patients, and prevalence was high in all the groups, but lower in cryoglobulinaemias secondary to CTD (p < 0.0001). Type II and type III essential cryoglobulinaemias differed significantly in renal involvement (p < 0.0001), cryocrit > 3% (p < 0.0001), C4 < 15 mg/dl (p < 0.001), HBsAg prevalence (p < 0.01) and purpura (p < 0.05). Despite the high prevalence of HCV markers in all groups, the role of HCV in essential cryoglobulinaemia is not well defined; HBV seems to play only a marginal role.